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ASTM D882

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ACTIVE STANDARD: D882-02 Standard Test Method for Tensile Properties of Thin Plastic Sheeting11. Scope1.1 This test method covers the determination of tensile properties of plastics in the form of thin sheeting, including film (less than 1.0 mm (0.04 in.) in thickness).Note 1—Film has been arbitrarily defined as sheeting having nominal thickness not greater than 0.25 mm (0.010 in.).Note 2—Tensile properties of plastics 1.0 mm (0.04 in.) or greater in thickness shall be determined according to Test Method D638.1.2 This test method may be used to test all plastics within the thickness range described and the capacity of the machine employed.1.2.1 Static Weighing, Constant-Rate-of-Grip Separation Test—This test method employs a constant rate of separation of the grips holding the ends of the test specimen.1.3 Specimen extension may be measured in these test methods by grip separation, extension indicators, or displacement of gage marks.1.4 A procedure for determining the tensile modulus of elasticity is included at one strain rate.Note 3—The modulus determination is generally based on the use of grip separation as a measure of extension; however, the desirability of using extensometers, as described in 5.2, is recognized and provision for the use of such instrumentation is incorporated in the procedure.1.5 Test data obtained by this test method is relevant and appropriate for use in engineering design.1.6 The values stated in SI units are to be regarded as the standard. The values in parentheses are provided for information only.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.Note 4—This test method is similar to ISO 527-3, but is not considered technically equivalent. ISO 527-3 allows for additional specimen configurations, specifies different test speeds, and requires an extensometer or gage marks on the specimen.2. Referenced Documents2.1 ASTM Standards:1 These test methods are under Mechanical Properties. Current edition approved April 10, 2002. Published June 2002. Originally published as D882-46 T. Last edition D882-01.D618 Practice for Conditioning Plastics for Testing2D638 Test Method for Tensile Properties of Plastics2D4000 Classification System for Specifying Plastic Materials3D5947 Test Methods for Physical Dimensions of Solid Plastic Specimens4D6287 Practice for Cutting Film and Sheeting Test Specimens4E4 Practices for Force Verification of Testing Machines5E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method62.2 ISO Standards:ISO 527-3 Plastics-Determination of Tensile Properties-Part 3: Test Conditions for Films and Sheets73. Terminology3.1 Definitions- definitions of terms and symbols relating to tension testing of plastics appear in the Annex to Test Method D638.3.1.1 line grips- grips having faces designed to concentrate the entire gripping force along a single line perpendicular to the direction of testing stress. This is usually done by combining one standard flat face and an opposing face from which protrudes a half-round.3.1.2 tear failure- a tensile failure characterized by fracture initiating at one edge of the specimen and progressing across the specimen at a low rate slow enough to produce an anomalous load-deformation curve.4. Significance and Use4.1 Tensile properties determined by this test method are of value for the identification and characterization of materials for control and specification purposes. Tensile properties may vary with specimen thickness, method of preparation, speed of testing, type of grips used, and manner of measuring extension. Consequently, where precision comparative results are desired, these factors must be carefully controlled. This test method shall be used for referee purposes, unless otherwise indicated in particular material specifications. For many materials, there may be a specification that requires the use of this test method, but with some procedural modifications that take precedence when adhering to the specification. Therefore, it is advisable to refer to that material specification before using this test method. Table 1 in Classification D 4000 lists the ASTM materials standards that currently exist.4.2 Tensile properties may be utilized to provide data for research and development and engineering design as well as quality control and specification. However, data from such tests cannot be considered significant for applications differing widely from the load-time scale of the test employed.2 Annual Book of ASTM Standards, V ol. 08.01.3 Annual Book of ASTM Standards, V ol. 08.02.4 Annual Book of ASTM Standards, V ol. 08.03.5 Annual Book of ASTM Standards, V ol. 03.01.6 Annual Book of ASTM Standards, V ol. 14.02.7 Available from American National Standards Institute, 25W, 43rd Street, 4th Floor, New York, NY 10036.4.3 The tensile modulus of elasticity is an index of the stiffness of thin plastic sheeting. Thereproducibility of test results is good when precise control is maintained over all test conditions. When different materials are being compared for stiffness, specimens ofidentical dimensions must be employed.4.4 The tensile energy to break (TEB) is the total energy absorbed per unit volume of the specimen up to the point of rupture. In some texts this property has been referred to as toughness. It is used to evaluate materials that may be subjected to heavy abuse or that might stall web transport equipment in the event of a machine malfunction in end-use applications. However, the rate of strain, specimen parameters, and especially flaws may cause large variations in the results. In that sense, caution is advised in utilizing TEB test results for end-use design applications.4.5 Materials that fail by tearing give anomalous data which cannot be compared with those from normal failure.5. Apparatus5.1 Testing Machine- a testing machine of the constant rate-of-crosshead-movement- type and comprising essentially the following:5.1.1 Fixed Member- a fixed or essentially stationary member carrying one grip.5.1.2 Movable Member- a moveable member carrying a second grip5.1.3 Grips- a set of grips for holding the test specimen between the fixed number and the movable member of the testing machine; grips can be either the fixed or self-aligning type. In either case, the gripping system must minimize both slippage and uneven stress distribution.5.1.3.1 Fixed grips are rigidly attached to the fixed and movable members of the testing machine. When this type of grip is used, care must be taken to ensure that the test specimen is inserted and clamped so that the long axis of the test specimen coincides with the direction of pull through the center line of the grip assembly.5.1.3.2 Self-aligning grips are attached to the fixed and movable members of the testing machine in such a manner that they will move freely into alignment as soon as a load is applied so that the long axis of the test specimen will coincide with the direction of the applied pull through the center line of the grip assembly. The specimens should be aligned as perfectly as possible with the direction of pull so that no rotary motion that may induce slippage will occur in the grips; there is a limit to the amount of misalignment self-aligning grips will accommodate.5.1.3.3 The test specimen shall be held in such a way that slippage relative to the grips is prevented insofar as possible. Grips lined with thin rubber, crocus-cloth, or pressure-sensitive tape as well as file-faced or serrated grips have been successfully used for many materials. The choice of grip surface will depend on the material tested, thickness, etc. Line grips padded on the round face with 1.0mm (40mil) blotting paper or filter paper have been found superior. Air-actuated grips have been found advantageous, particularly in the case of materials that tend to ‘neck’ into the grips, since pressure is maintained at all times. In cases where samples frequently fail at the edge of the grips, it may be advantageous to increase slightly the radius of curvature of the edges where the grips come in contact with the test area of the specimen.5.1.4 Drive Mechanism- a drive mechanism for imparting to the movable member a uniform, controlled velocity with respect to the stationary member. The velocity shall beregulated as specified in Section 9.5.1.5 Load Indicator- a suitable load-indicating mechanism capable of showing the total tensile load carried by the test specimen held by the grips. This mechanism shall be essentially free of inertial lag at the specified rate of testing (see Note 5). Unless a suitable extensometer is used (see 5.2), the motion of the weighing system shall not exceed 2% of the specimen extension within the range being measured. The load indicator shall determine the tensile load applied to the specimen with an accuracy of ±1% of the indicated value, or better. The accuracy of the testing machine shall be verified in accordance with Practices E4.5.1.6 Crosshead Extension Indicator- a suitable extension-indicating mechanism capable of showing the amount of change in the separation of the grips, that is, crosshead movement. This mechanism shall be essentially free of inertial lag at the specified rate of testing (Note 5) and shall indicate the crosshead movement with an accuracy of ±1% of the indicated value, or better.5.2 Extensometer (Optional)- a suitable instrument may, if desired, be used for determining the distance between two designated points on the test specimen as the specimen is stretched. This apparatus, if employed, shall be so designed as to minimize stress on the specimen at the contact points of the specimen and the instrument (see 8.3). It is desirable that this instrument automatically records the distance, or any change in it, as a function of the load on the test specimen or of the elapsed time from the start of the test, or both. If only the latter is obtained, load-time data must also be taken. This instrument must be essentially free of inertial lag at the specified speed of testing (see Note 5).5.2.1 Modulus of Elasticity and Low-Extension Measurements- extensometers used for modulus of elasticity and low extension (less than 20% elongation) measurements shall, at a minimum, be accurate to ±1% and comply with the requirements set forth in Practice E83 for a Class C instrument.5.2.2 High-Extension Measurements- instrumentation and measuring techniques used for high-extension (20% elongation or greater) measurements shall be accurate to ±10% of the indicated value, or better.Note 5- A sufficiently high response speed in the indicating and recording system for the load and extension data is essential. The response speed required of the system will depend in part on the material tested (high or low elongation) and the rate of straining.5.3 Thickness Gage- a dead-weight dial micrometer as prescribed in Method C of Test Methods D5947, or an equivalent measuring device, reading to 0.0025 mm (0.0001 in.) or less.5.4 Width-Measuring Devices- suitable test scales or other width measuring devices capable of measuring 0.25mm (0.010 in.) or less.5.5 Specimen Cutter- for the apparatus and techniques for cutting film and sheeting used in this test method, refer to Practice D6287.5.5.1 Devices that use razor blades have proven especially suitable for materials having an elongation-at-fracture above 10 to 20%.5.5.2 The use of punch press or striking dies are not recommended because poor and inconsistent specimen edges may be produced.6. Test Specimens6.1 The test specimens shall consist of strips of uniform width and thickness at least 50mm (2 in.) longer than the grip separation used.6.2 The nominal width of the specimens shall be not less than 5.0mm (0.20 in.) or greater than 25.4mm (1.0 in.).6.3 A width-thickness ratio of at least eight shall be used. Narrow specimens magnify effects of edge strains or flaws, or both.6.4 The utmost care shall be exercised in cutting specimens to prevent nicks and tears which are likely to cause premature failures (Note 6). The edges shall be parallel to within 5% of the width over the length of the specimen between the grips.Note 6- Microscopical examinations of specimens may be used to detect flaws due to sample or specimen preparation.6.5 Whenever possible, the test specimens shall be selected so that thickness is uniform to within 10% of the thickness over the length of the specimen between the grips in the case of materials 0.25mm (0.010 in.) or less in thickness and to within 5% in the case of materials greater than 0.25mm (0.010 in.) in thickness but less than 1.0mm (0.040 in.) in thickness. Note 7- In cases where thickness variations are in excess of those recommended in 6.5, results may not be characteristic of the material under test.6.6 If the material is suspected of being anisotropic, two sets of test specimens shall be prepared having their long axes respectively parallel with and normal to the suspected direction of anisotropy.6.7 For tensile modulus of elasticity determinations, a specimen gage length of 250mm (10 in.) shall be considered as standard. This length is used in order to minimize the effects of grip slippage on test results. When this length is not feasible, test sections as short as100mm (4 in.) may be used if it has been shown that results are not appreciably affected. However, the 250mm gage length shall be used for referee purposes. The speed of testing of shorter specimens must be adjusted in order for the strain rate to be equivalent to that of the standard specimen.Note 8- Two round robin tests8 have shown that, for materials of less than 0.25mm (10mil) thickness, line grips padded on the round side with 1.0mm (40mil) blotting paper give the same results with a 100mm test section as a 250mm test section produces with flat-face grips.Note 9- Excessive jaw slippage becomes increasingly difficult t overcome in cases where high modulus materials are tested in thicknesses greater than 0.25mm (0.010 in.).7. Conditioning7.1 Conditioning- condition the test specimens at 23 ± 2°C (73.4 ± 3.6°F) and 50 ± 5% relative humidity for not less than 40 h prior to test in accordance with Procedure A of8 Supporting Data are available from ASTM Headquarters. Request RR: D20-1058.Practice D618 unless otherwise specified by contract or the relevant ASTM material specification. Reference pre-test conditioning, to settle disagreements, shall apply tolerances of ±1°C (1.8°F) and ± 2 % relative humidity.7.2 Test Conditions- conduct the tests at 23 ± 2°C (73.4 ± 3.6°F) and 50 ± 5% relative humidity unless otherwise specified by contract or the relevant ASTM material specification. Reference testing conditions, to settle disagreements, shall apply tolerances of ±1°C (1.8°F) and ±2% relative humidity.8. Number of Test Specimens8.1 In the case of isotropic materials, at least five specimens shall be tested from each sample.8.2 In the case of anisotropic materials, at least ten specimens, five normal and five parallel with the principal axis of anisotropy, shall be tested from each sample.8.3 Specimens that fail at some obvious flaw or that fail outside the gage length shall be discarded and retests made unless such flaws or conditions constitute a variable whose effect is being studied. However, jaw breaks (failures at the grip contact point) are acceptable if it has been shown that results from such tests are in essential agreement with values obtained from breaks occurring within the gage length.Note 10: In the case of some materials, examination of specimens, prior to and following testing, under crossed optical polarizers (polarizing films) provides a useful means of detecting flaws which may be, or are, responsible for premature failure.9. Speed of Testing9.1 The speed of testing is the rate of separation of the two members (or grips) of the testing machine when running idle (under no load). This rate of separation shall be maintained within 5% of the no-load value when running under full capacity load.9.2 The speed of testing shall be calculated from the required initial strain rate as specified in Table 1. The rate of grip separation may be determined for the purpose of these test methods from the initial strain rate as follows:A=BC(1) Where:A= rate of grip separation, mm (or in.)/minB= initial distance between grips, mm (or in.), andC= initial strain rate, mm/mm·min (or in./in.·min).9.3 The initial strain rate shall be as in Table 1 unless otherwise indicated by the specification for the material being tested.Note 11- results obtained at different initial strain rates are not comparable; consequently, where direct comparisons between materials in various elongation classes are required, a single initial strain rate should be used. For some materials it may be advisable to select the strain rates on the basis of percent elongation at yield.9.4 In cases where conflicting material classification, as determined by percent elongation at break values, results in a choice of strain rates, the lower rate shall be used.9.5 If modulus values are being determined separate specimens shall be used whenever strain rates and specimen dimensions are not the same as those employed in the test for other tensile properties.10. Procedure10.1 Select a load range such that specimen failure occurs within its upper two thirds. A few trial runs may be necessary to select a proper combination of load range and specimen width.10.2 Measure the cross-sectional area of the specimen at several points along its length. Measure the width to an accuracy of 0.25 mm (0.010 in.) or better. Measure the thickness to an accuracy of 0.0025mm (0.0001 in.) or better for films less than 0.25 mm (0.010 in.) in thickness and to an accuracy of 1% or better for films greater than 0.25 mm (0.010 in.) but less than 1.0 mm (0.040 in.) in thickness10.3 Set the initial grip of separation in accordance with Table 1.10.4 Set the rate of grip separation to give the desired strain rate, based on the initial distance between the grips, in accordance with Table 1. Zero the calibrated load weighing system, extension indicator(s) and recording system.Note 12: Extensometers may be used for modulus of elasticity determinations with the expectation of obtaining more accurate values than may be obtained using grip separation as the effective gage length. Precautions should be taken to ensure that extensometer slippage and undue stressing of the specimen do not occur. Refer also to 6.7.10.5 In cases where it is desired to measure a test section other than the total length between the grips, mark the ends of the desired test section with a soft, fine wax crayon or with ink. Do not scratch these marks onto the surface since such scratches may act as stress raisers and cause premature specimen failure. Extensometers may be used if available; in this case, the test section will be defined by the contact points of the extensometer.Note 13: measurement of a specific test section is necessary with some materials having long elongation. As the specimen elongates, the accompanying reduction in are results in a loosening of material at the inside edge of the grips. This reduction and loosening moves back into the grips as further elongation and reduction10.6 Place the test specimen in the grips of the testing machine, taking care to align the longaxis of the specimen with an imaginary line joining the points of attachment of the grips to the machine. Tighten the grips evenly and firmly to the degree necessary to minimizeslipping of the specimen during test.10.7 Start the machine and record load versus extension10.7.1 When the total length between the grips is used as the test area, record loadversus grip separation10.7.2 When a specific test area has been marked on the specimen, follow thedisplacement of the edge boundary lines with respect to each other with dividers or some other suitable devices. If a load-extension curve is desired, plot various extensions versus corresponding loads sustained, as measured by the load indicator.10.7.3 When an extensometer is used, record load versus extension of the test area measured by the extensometer10.8 If modulus values are being determined, select a load range and chart rate to produce a load-extension curve of between 30 and 60° to the X axis. For maximum accuracy, use the most sensitive load scale for which this condition can be met. The test may be discontinued when the load-extension curve deviates from linearity.10.9 In the case of materials being evaluated for secant modulus, the test may be discontinued when the specified extension has been reached.10.10 If tensile energy to break is being determined, some provision must be made for integration of the stress-strain curve. This may be either an electronic integration during the test or a subsequent determination from the area of the finished stress-strain curve (see Annex A2).11. Calculation11.1 Toe compensation shall be made in accordance with Annex A1 unless it can be shown that the toe region of the curve is not due to the takeup of slack, seating of the specimen or other artifact, but rather is an authentic material response.11.2 Breaking Factor (nominal) shall be calculated by dividing the maximum load by the original minimum width of the specimen. The result shall be expressed in force per unit of width, usually newtons per meter (or pounds per inch) of width, and reported to three significant figures. The thickness of the film shall always be stated to the nearest 0.0025mm (0.0001 in.).Example- Breaking Factor= 1.75 kN/m (10.0 lbf/in.) of width for 0.1300-mm (0.0051-in.) thickness.Note 14- This method of reporting is useful for very thin films (0.13mm (0.005 in.) and less) for which breaking load may not be proportional to cross-sectional area and whose thickness may be difficult to determine with precision. Furthermore, films which are in effect laminar due to orientation, skin effects, nonuniform crystallinity, etc., have tensile properties disproportionate to cross-sectional area.11.3 Tensile Strength (nominal) shall be calculated by dividing the maximum load by the original minimum cross-sectional area of the specimen. The result shall be expressed inforce per unit area, usually megapascals (or pounds-force per square inch). This value shall be reported to three significant figures.Note 15- When tear failure occurs, so indicate and calculate results based on load and elongation at which tear initiates, as reflected in the load-deformation curve.11.4 Tensile Strength at Break (nominal) shall be calculated in the same way as the tensile strength except that the load at break shall be used in place of the maximum load (Note 15 and Note 16)Note 16- In many cases tensile strength and tensile strength at break are identical.11.5 Percent Elongation at Break shall be calculated by dividing the extension at the moment of rupture of the specimen by the initial gage length of the specimen and multiplying by 100. When the gage marks or extensometers are used to define a specific test section, only this length shall be used in the calculation; otherwise the distance between the grips shall be used. The result shall be expressed in percent and reported to two significant figures (Note 15). 11.6 Yield Strength, where applicable, shall be calculated by dividing the load at the yield point by the original minimum cross-sectional area of the specimen. The result shall be expressed in force per unit area, usually megapascals (or pounds-force per square inch). This value shall be reported to three significant figures. Alternatively, for materials that exhibit Hookean behavior in the initial part of the curve, an offset yield strength may be obtained as described in the Appendix of Test Method D638. In this case the value should be given as “yield strength at __% offset.”11.7 Percent Elongation at Yield, where applicable, shall be calculated by dividing the extension at the yield point by the initial gage length of specimen and multiplying by 100. when gage marks or extensometers are used to define a specific test section, only this length shall be used in the calculation. Before calculating, correct the extension for “toe compensation” as described in Annex A1. The results shall be expressed in percent and reported to two significant figures. When offset yield strength is used, the elongation at the offset yield strength may be calculated.11.8 Elastic Modulus shall be calculated by drawing a tangent to the initial linear portion ofthe load-extension curve, selecting any point on this tangent, and dividing the tensile stress by th e corresponding strain. Before calculating, correct the extension for “toe compensation” as described in Annex A1. For purposes of this determination, the tensile stress shall be calculated by dividing the load by the average original cross section of the test section. The result shall be expressed in force per unit area, usually megapascals (or pounds-force per square inch), and reported to three significant figures.11.9 Secant Modulus, at a designated strain, shall be calculated by dividing the corresponding stress (nominal) by the designated strain. Elastic modulus values are preferable and shall be calculated whenever possible. However, for materials where no proportionality is evident, the secant value shall be calculated. Draw the tangent as directed in A1.3 and Fig. A1.2 of Annex A1, and mark off the designated strain from the yield point where the tangent line goes through zero stress. The stress to be used in the calculation is then determined by dividing the load at the designated strain on the load-extension curve by the original average cross-sectional area of the specimen.11.10 Tensile Energy to Break , where applicable, shall be calculated by integrating the energy per unit volume under the stress-strain curve or by integrating the total energy absorbed and dividing it by the volume of the original gage region of the specimen. As indicated in Annex A2, this may be done directly during the test by an electronic integrator, or subsequently by computation form the area of the plotted curve. The result shall beexpressed in energy per unit volume, usually in megajoules per cubic meter (or inch-pounds-force per cubic inch). This value shall be reported to two significant figures.11.11 For each series of tests, the arithmetic mean of all values obtained shall be calculated to the proper number of significant figures.11.12 The standard deviation (estimated) shall be calculated as follows and reported to two significant figures:s=)1/()(22--∑n X n XWhere:s = estimated standard deviation X = value of a single observationn= number of observations, and X = arithmetic mean of the set of observations.12. Report12.1 Report the following information: 12.1.1 Complete identification of the material tested, including type, source,manufacturer’s code number, form, principal dimensions, pervious history, and orientation of samples with respect to anisotropy (if any),12.1.2 Method of preparing test specimens, 12.1.3 Thickness, width, and length of test specimens,12.1.4 Number of specimens tested, 12.1.5 Strain rate employed12.1.6 Grip separation (initial), 12.1.7 Crosshead speed (rate of grip separation)12.1.8 Gage length (if different from grip separation) 12.1.9 Type of grips used, including facing (if any),12.1.10 Conditioning procedure (test conditions, temperature, and relative humidity if nonstandard),12.1.11 Anomalous behavior such as tear failure and failure at a grip, 12.1.12 Average breaking factor and standard deviation12.1.13 Average tensile strength (nominal) and standard deviation, 12.1.14 Average tensile at break (nominal) and standard deviation,12.1.15 Average percent elongation at break and standard deviation 12.1.16 Where applicable, average tensile energy to break and standard deviation 12.1.17 In the case of materials exhibiting “yield” phenomenon: average yield strength and standard deviation; and average percent elongation at yield and standarddeviation 12.1.18 For materials which do not exhibit a yield point average __% offset yield。

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ASTM D882-02(中文)塑料薄板材抗拉特性的试验方法[1]

ASTM D882-02(中文)塑料薄板材抗拉特性的试验方法[1]

ASTM D 882-02 : 测量塑料薄膜和薄片材拉伸性能测量塑料薄膜和薄片材拉伸性能的标准方法1. 测试应用范围1.1本测试用于测试塑料薄膜和片材（厚度小于1.0毫米）的拉伸性能。

注1——片材厚度小于0.25毫米（0.01英寸）的即被定义为薄膜。

注2——厚度为1.0毫米（0.04英寸）或者更厚片材的拉伸测试试验要根据D638进行。

1.2本测试应该被用来测试所有在所描述的厚度范围以内以及在要使试验机的负荷量程以内的全部塑料材料。

1.2.1静态过磅——恒定分离速率的夹具分离测试——在本方法中，夹具以恒定的速度抓住试样的一端将其分离。

1.3在这些测试方法中，测量试样的伸长可以从夹具分离距离、伸长指示器和标距线的位移得出。

1.4包括了在一个应变速率时测试拉伸弹性模量的步骤。

注3：模量的测量一般基于夹具分离的距离作为试样的伸长值。

然而，本标准也包括了使用如图5.2所述的伸长仪的情况。

1.5本测试所得的数据适用于工程设计或与其相关。

1.6 SI制单位即作为标准单位。

括号内的数值仅供参考。

1.7 本标准不适用于解决所相关的所有安全问题，仅涉及到它的应用。

建立相关的安全健康规则和使用前相关规定是使用者的责任。

规定2给出了相关的安全参考文献。

注4—本测试与ISO527-3类似，但在技术上二者并不能等同。

在ISO527-3中允许其他试样类型，特定的测试速度并要求使用伸长计或在试样上作测量标线。

2.参考文献2.1 ASTM标准D 618放置测试塑料的实施方法。

D 638测试塑料的拉伸方法。

D 4000塑料材料的分类方法。

E 4 试验机的负荷校正方法。

E 691 在实验室间进行测试精密度检测的方法。

2.2 ISO标准ISO527-3确定塑料的拉伸性质—第三部分：塑料薄膜和片材的测试条件。

3. 术语3.1定义——与塑料拉伸相关的术语或者符号在D 638的附件中。

3.1.1夹具——所设计的夹具可以将整个夹取应力集中到与拉伸方向垂直的一条线上。

ASTMD剥离强度测试标准中文版

ASTMD剥离强度测试标准中文版

ASTMD剥离强度测试标准中⽂版压敏胶带剥离强度测试标准1. 范围1.1 这些测试⽅法主要⽤于压敏胶带剥离强度的测试。

1.1.1 ⽅法 A：单⾯胶从标准钢板或其他类似表⾯的平板上180°剥离的测试⽅法。

1.1.2 ⽅法B：单⾯背衬胶粘性的测试⽅法。

1.1.3 ⽅法C：双⾯胶与标准钢板粘性的测试⽅法。

1.1.4 ⽅法D：单⾯胶或双⾯胶与离型纸的粘性的测试⽅法。

1.1.5 ⽅法E：⽆基材胶带与标准钢板的粘性的测试⽅法。

1.1.6 ⽅法F：单⾯胶与标准钢板90°剥离的测试⽅法。

1.2 这些测试⽅法是给定压敏胶带粘性测试的统⼀评定⽅法，这评定可以针对⼀卷，两卷之间或⼀批。

1.3 不同的基材和（或）胶质都会影响测定结果，因此，这些⽅法不适⽤不统⼀的胶质。

1.4 这些测试⽅法不适⽤于⼀些相对硬质的基材、衬⾥或在低强度下⾼粘性背胶的测试。

这些特性对测试结果有很⼤的影响，因⽽不能真正代表粘⼒。

1.5 测试数值⽤ IS 或英⼨—磅做为单位，在每个单位系统中数值的规定都是不同的，因此，每个系统必须使⽤⾃⼰的单位。

1.6 这些标准没⽤强调在操作过程中可能会发⽣的所有安全隐患。

标准使⽤者有义务去建⽴⼀个安全健康的操纵规则。

4. 测试⽅法概要4.1 ⽅法 A——单⾯胶 180°剥离——⽤可控压⼒把胶带粘贴到标准测试板上。

测试时，以恒定的速度180°⾓从测试板上剥离。

4.2 ⽅法 B——单⾯背衬胶的粘性——胶带式样⼀粘贴到测试钢板上，取另⼀式样粘贴到式样以的背⾯，然后按⽅法A 进⾏测试。

4.3 ⽅法C——双⾯胶4.3.1 表⾯粘性——把双⾯胶的正⾯贴到不锈钢板上，衬⾥⾯朝外。

撕去衬纸，贴⼀层 0.025mm（0.001in）的聚酯薄膜，接下来按⽅法A 进⾏测试。

4.3.2 衬⾥粘⼒——在双⾯胶的正⾯贴上0.025mm 的聚酯薄膜，然后撕去衬纸贴到不锈钢板上。

接下来的测试同⽅法A。

4.4 ⽅法 D——测试离型纸胶带（单⾯或者双⾯）的粘性——把胶带粘贴到测试钢板上，衬⾥⾯朝外。

HDPE物性数据表

HDPE物性数据表

①原料描述部分规格级别：电缆绝缘料外观颜色：本色用途概述：用于低、中、高速绝缘生产线备注说明：性能：由乙烯、丁烯集合而成的双峰高密度聚乙烯，并含有适量助剂的本色粒料。

因为其分子量呈双峰分布,所以它具有优异的加工性能、很好的力学性能及良好的电性能。

②原料技术数据性能项目试验条件［状态] 测试方法测试数据数据单位基本性能密度/ / 0.941—0。

959 g/cm3熔体流动速率/ / ≤1。

0 g/10min机械性能拉伸强度/ / ≥19。

0 MPa 断裂伸长率/ / ≥400% 耐环境应力开裂性48h / ≤2/10/电气性能介电常数1MHz / ≤2.40/体积电阻率/ / ≥1×1013Ω？m①原料描述部分规格级别：挤出级外观颜色：-—-用途概述：用途：供水管，工业用管子。

备注说明：特性：电子光谱法，高冲击和高强度。

②原料技术数据性能项目试验条件[状态］测试方法测试数据数据单位基本性能熔体流动速率/ ASTM D-1238 0。

12 g/10min 密度/ ASTM D—1505 0.950 g/cm3机械性能屈服拉伸强度/ ASTM D—638 220 Kg/cm2断裂拉伸强度/ ASTM D-638 390 Kg/cm2最终拉伸率/ ASTM D-638 〉500 ％挠曲强度/ ASTM D-747 8，500 Kg/cm2洛氏硬度/ ASTM D-785 50 R冲击强度/ ASTM D-256 30 kg？cm/cm 耐环境应力破裂/ ASTM D-1693 〉1,000 F50hr热性能脆化温度/ ASTM D—746 <—80 ℃熔点/ ASTM D-2117 131 ℃维卡软化点/ ASTM D—1525 122 ℃①原料描述部分规格级别：管材级外观颜色：—-—用途概述：农业排灌管、热水管、支架备注说明: 类型：挤塑②原料技术数据性能项目试验条件［状态] 测试方法测试数据数据单位基本性能熔体流动速率/ / 0.15 g/10min 密度/ / 0.954 g/cm3机械性能拉伸强度/ / 18。

ASTM D883–00 塑料制品的术语

ASTM D883–00 塑料制品的术语

Designation:D883–00Standard Terminology Relating toPlastics1This standard is issued under thefixed designation D883;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1.Scope*1.1This terminology covers definitions of technical terms used in the plastics industry.Terms that are generally under-stood or adequately defined in other readily available sources are not included.1.2When a term is used in an ASTM document for which Committee D20is responsible it is included only when judged, after review,by Subcommittee D20.92to be a generally usable term.1.3Definitions that are identical to those published by another standards body are identified with the abbreviation of the name of the organization;for example,IUPAC is the International Union of Pure and Applied Chemistry.1.4A definition is a single sentence with additional infor-mation included in discussion notes.It is reviewed every5 years;the year of last review is appended.1.5For literature related to plastics terminology,see Appen-dix X1.2.Referenced Documents2.1ASTM Standards:C162Terminology of Glass and Glass Products2D638Test Method for Tensile Properties of Plastics3D747Test Method for Apparent Bending Modulus of Plastics by Means of a Cantilever Beam3D790Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materi-als3D882Test Methods for Tensile Properties of Thin Plastic Sheeting3D907Terminology of Adhesives4D1003Test Method for Haze and Luminous Transmittance of Transparent Plastics3D1566Terminology Relating to Rubber5D4703Practice for Compression Molding ThermoplasticMaterials into Test Specimens,Plaques,or Sheets6E308Practice for Computing the Colors of Objects by Using the CIE System73.Terminology3.1Definitions:A-stage,n—an early stage in the preparation of certain thermosetting resins in which the material is still soluble in certain liquids,and may be liquid or capable of becoming liquid upon heating.D ISCUSSION—Sometimes referred to as Resol.(See also B-stage andC-stage.)(1978)8acetal plastics,n—plastics based on polymers having a predominance of acetal linkages in the main chain.(See also polyoxymethylene.)(1985)acrylic plastics—plastics based on polymers made with acrylic acid or a structural derivative of acrylic acid.(1982) addition polymerization—polymerization in which mono-mers are linked together without the splitting off of water or other simple molecules.(1983)adiabatic extrusion—a method of extrusion in which,after the extrusion apparatus has been heated sufficiently by conventional means to plastify the material,the extrusion process can be continued with the sole source of heat being the conversion of the drive energy,through viscous resis-tance of the plastic mass in the extruder.(1978)aging,n—(1)the effect on materials of exposure to an environment for an interval of time.(2)the process of exposing materials to an environment for an interval of time. (1973)alkyd plastics—plastics based on alkyd resins.(1980)alkyd resin—a polyester convertible into a crosslinked form; requiring a reactant of functionality higher than two,or having double bonds.(1982)alloy,n(in plastics)—two or more immiscible polymers united,usually by another component,to form a plastic resin having enhanced performance properties.allyl plastics—plastics based on allyl resins.(1978)1This terminology is under the jurisdiction of ASTM Committee D20on Plastics and is the direct responsibility of Subcommittee D20.92on Terminology.Current edition approved Aug.10,2000.Published October2000.Originally published as D883–st previous edition D883–99.2Annual Book of ASTM Standards,V ol15.02.3Annual Book of ASTM Standards,V ol08.01. 4Annual Book of ASTM Standards,V ol15.06. 5Annual Book of ASTM Standards,V ol09.01.6Annual Book of ASTM Standards,V ol08.03.7Annual Book of ASTM Standards,V ol06.01.8Date indicates year of introduction or latest review or revision. 1*A Summary of Changes section appears at the end of this standard. Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.allyl resin—a resin made by polymerization of chemical compounds containing the allyl group.(1978)amino plastics,n—plastics based on amino resins.(1978) amino resin,n—a resin made by polycondensation of a compound containing amino groups,such as urea or melamine,with an aldehyde,such as formaldehyde,or an aldehyde-yielding material.(1985)apparent density—See density,apparent.aromatic polyester,n—a polyester derived from monomers in which all the hydroxyl and carboxyl groups are linked directly to aromatic nuclei.(1986)artificial weathering—exposure to laboratory conditions, which may be cyclic,involving changes in temperature, relative humidity,radiant energy,and any other elements found in the atmosphere in various geographical areas.D ISCUSSION—The laboratory exposure conditions are usually inten-sified beyond those encountered in actual outdoor exposure in an attempt to achieve an accelerated effect.(1980)average injection velocity,n—the mean value of the velocity of the molten plasticflow front within a cavity during the injection time that is calculated from the shot volume and injection time.D ISCUSSION—The average injection velocity is calculated as follows:V av5V st i3A c3nwhere:V av=average injection velocity,mm/s,V s=shot volume,mm3,t i=injection time,s,A c=cross section of the cavity,mm2,andn=number of cavities.This calculation is valid for molds containing a single cavity or those containing identical multi-specimen cavities only and not for family molds.B-stage,n—an intermediate stage in the reaction of certain thermosetting resins in which the material swells when in contact with certain liquids and softens when heated,but may not entirely dissolve or fuse.D ISCUSSION—The resin in an uncured thermosetting molding com-pound is usually,in this stage,sometimes referred to as Resitol.(See also A-stage and C-stage.)(1978)bag modeling—a method of molding or laminating which involves the application offluid pressure,usually by means of air,steam,water or vacuum,to aflexible barrier material which transmits the pressure to the material being molded or bonded.D ISCUSSION—The process is usually employed for forming shapesfrom preformed laminates comprising afibrous sheet impregnated with an A-stage or a B-stage thermosetting resin.(1986)binder,n—in a reinforced plastic,the continuous phase which holds together the reinforcement.D ISCUSSION—During fabrication,the binder,which may be eitherthermoplastic or thermoset,usually undergoes a change in state.(1978) biodegradable plastic,n—See degradable plastic.blister,n—an imperfection,a rounded elevation of the surfaceof a plastic,with boundaries that may be more or less sharply defined,somewhat resembling in shape a blister on the human skin.(1983)block copolymer—an essentially linear copolymer in which there are repeated sequences of polymeric segments of different chemical structure.(1982)blocking,n—unintentional adhesion between plasticfilms or between afilm and another surface.(1983)bloom,n—a visible exudation or efflorescence on the surface of a material.(1972)blowing agent—a compounding ingredient used to produce gas by chemical or thermal action,or both,in manufacture of hollow or cellular articles.(1983)blow molding—a method of fabrication in which a heated parison is forced into the shape of a mold cavity by internal gas pressure.(1985)branched polyethylene plastics,n—those containing signifi-cant amounts of both short-chain and long-chain branching and having densities in the0.910to0.940g/cm3range.D ISCUSSION—These plastics,usually produced commercially by freeradical polymerization,are subcategorized by density level;low density polyethylene plastic and medium density polyethylene plastic.bulk density,n—the weight per unit volume of a loosely packed material,such as a molding powder or pellets.D ISCUSSION—This term should not be used synonymously withapparent density.bulk factor,n—the ratio of the volume of a given mass of molding material to its volume in the molded form.D ISCUSSION—The bulk factor is also equal to the ratio of the densityof the material to its apparent density in the unmolded form.(ISO) (1982)bulk molding compound(BMC),n—a putty-like mixture of any thermosetting resin containingfillers,fiber reinforce-ments,catalysts and thickening agents,or thermoplastic polymers,often extruded into logs or ropes.D ISCUSSION—BMC is suitable for molding by any one of threematched-metal-mold processes—compression molding,transfer mold-ing,or injection molding.(1983)butylene plastics—plastics based on resins made by the polymerization of butene or copolymerization of butene with one or more unsaturated compounds,the butene being in greatest amount by weight.(1975)C-stage,n—thefinal stage in the reaction of certain thermo-setting materials in which they have become practically insoluble and infusible.D ISCUSSION—The resin in a fully cured thermoset molding is,in thisstage,sometimes referred to as Resite.(See also A-stage and B-stage.) (1986)castfilm—afilm made by depositing a layer of plastic,either molten,in solution,or in a dispersion,onto a surface, solidifying and removing thefilm from the surface.(1982) cavity,n—in specimen preparation,the part of the hollow space of a mold that forms one specimen.cell,n—a small cavity surrounded partially or completely by walls.(1983)cell,closed—a cell totally enclosed by its walls and hence not interconnecting with other cells.(ISO)(See cell and cell, open.)(1983)cell,open—a cell not totally enclosed by its walls and hence interconnecting with other cells.(See cell and cell,closed.) (1983)cellular plastic—a plastic containing numerous cells,inten-tionally introduced,interconnecting or not,distributed throughout the mass.(See also syntactic cellular plastics.) (1983)cellular striation,n—a condition characterized by a layer within a cellular material that differs greatly from the characteristic cell structure.cellulosic plastics,n—plastics based on cellulose compounds, such as esters(cellulose acetate)and ethers(ethyl cellulose). (1985)chalking,n—(plastics)a powdery residue on the surface of a material resulting from degradation or migration of an ingredient,or both.D ISCUSSION—Chalking may be designed-in characteristic.(1980) chemically foamed polymeric material—a cellular material in which the cells are formed by gases generated from thermal decomposition or other chemical reaction.(1982) chlorinated poly(vinyl chloride)—a poly(vinyl chloride) (PVC)polymer modified by additional chlorination.(2000) chlorinated poly(vinyl chloride)plastics—plastics based on chlorinated poly(vinyl chloride)in which the chlorinated poly(vinyl chloride)is in the greatest amount by weight. (1978)chlorofluorocarbon plastics—plastics based on polymers made with monomers composed of chlorine,fluorine,and carbon only.(ISO)(1983)chlorofluorohydrocarbon plastics,n—plastics based on poly-mers made with monomers composed of chlorine,fluorine, hydrogen,and carbon only.(ISO)(1982)circuit—infilament winding,the winding produced by a single revolution of mandrel or form.(1978)closed-cell cellular plastics—cellular plastics in which almost all the cells are noninterconnecting.(1983)coldflow—See creep.(1983)cold molding—a special process of compression molding in which the molding is formed at room temperature and subsequently baked at elevated temperatures.(1982) collapse,n—inadvertent densification of cellular material dur-ing manufacture resulting from breakdown of cell structure. (1982)composite,n—a solid product consisting of two or more distinct phases,including a binding material(matrix)and a particulate orfibrous material.D ISCUSSION—Examples are moulding material containing reinforcingfibers,particulatefillers,or hollow spheres.(1991) compost—the product of composting.compostable plastic—a plastic that undergoes biological deg-radation during composting to yield carbon dioxide,water, inorganic compounds,and biomass at a rate consistent with other known compostable materials and leaves no visually distinguishable or toxic residues.(1996)compound,n—an intimate admixture of(a)polymer(s)with all the materials necessary for thefinished product.(1983) compression molding—the method of molding a material already in a confined cavity by applying pressure and usually heat.(1986)condensation polymer—a polymer made by condensation polymerization.(1983)condensation polymerization—polymerization in which monomers are linked together with the splitting off of water or other simple molecules.(1983)contact pressure molding,n—a method of molding or lami-nating in which the pressure,usually less than70kPa(10 psi),is only slightly more than necessary to hold the materials together during the molding operation.(1985) cooling time,n—in molding,the time interval from the start of forward screw movement until the mold starts to open. copolymer—See polymer.(1983) copolymerization—See polymerization.(1983)crater,n—a small,shallow surface imperfection.(1978) crazing,n—apparentfine cracks at or under the surface of a plastic.D ISCUSSION—The crazed areas are composed of polymeric materialof lower density than the surrounding matrix.(1978)creep,n—the time-dependent part of strain resulting from stress.(1983)cross laminate—a laminate in which some of the layers of material are oriented approximately at right angles to the remaining layers with respect to the grain or strongest direction in tension.(See also parallel laminate).(1982) crosslinking,n—the formation of a three dimensional polymer by means of interchain reactions resulting in changes in physical properties.(1983)cross section of the cavity,n—in a mold for test specimens, the area of a planar section perpendicular to theflow pattern duringfilling of the mold that forms the critical portion of the test specimen.cure,v—to change the properties of a polymeric system into a more stable,usable condition by the use of heat,radiation,or reaction with chemical additives.D ISCUSSION—Cure may be accomplished,for example,by removal ofsolvent or by crosslinking.(ISO)(1983)cure cycle—the schedule of time periods,at specified condi-tions,to which a reacting thermosetting material is subjected to reach a specified property level.(1983)cure time—the period of time that a reacting thermosetting material is exposed to specific conditions to reach a specified property level.(1983)cut-layers—as applied to laminated plastics,a condition of the surface of machined or ground rods and tubes and of sanded sheets in which cut edges of the surface layer or lower laminations are revealed.(1978)cycle time,n—in molding,the total time used to carry out a complete sequence of operations making up the molding cycle.degradable plastic,n—a plastic designed to undergo a sig-nificant change in its chemical structure underspecificenvironmental conditions resulting in a loss of some prop-erties that may vary as measured by standard test methods appropriate to the plastic and the application in a period of time that determines its classification.(1991) biodegradable plastic,n—a degradable plastic in which the degradation results from the action of naturally-occurring micro-organisms such as bacteria,fungi,and algae.D ISCUSSION—The level of biodegradability may be indicated asshown in subordinate definitions for biodegradable plastics.(1991) hydrolytically degradable plastic,n—a degradable plastic in which the degradation results from hydrolysis.D ISCUSSION—The level of hydrolytic degradability may be indicatedas shown in subordinate definitions for hydrolytically degradable plastic.(1991)oxidatively degradable plastic,n—a degradable plastic in which the degradation results from oxidation.D ISCUSSION—The level of oxidative degradability may be indicatedas shown in subordinate definitions for oxidatively degradable plastic.(1991)photodegradable plastic,n—a degradable plastic in which the degradation results from the action of natural daylight.D ISCUSSION—The level of photodegradability may be indicated asshown in subordinate definitions for photodegradable plastic.(1991) degradation,n—a deleterious change in the chemical struc-ture,physical properties,or appearance of a plastic.(1980) delamination,n—the separation of the layers of material in a laminate.(1978)density,apparent—the weight in air of a unit volume of a material.D ISCUSSION—This term is sometimes used synonymously with bulkdensity.(1973)density,bulk—the weight per unit volume of a material including voids inherent in material as tested.D ISCUSSION—This term is commonly used for material such asmolding powder.(1973)depth,n—in the case of a beam,the dimension parallel to the direction in which the load is applied.(1978)dome,n—in reinforced plastics,an end of afilament-wound cylindrical container.(1985)dry-blend,n—a dry compound prepared withoutfluxing or addition of solvent(also called powder blend).(1983)dry-spot,n—an imperfection in reinforced plastics,an area of incomplete surfacefilm where the reinforcement has not been wetted with resin.(1983)durometer,n—an instrument for measuring indentation hard-ness.elastomer,n—a macromolecular material that at room tem-perature returns rapidly to approximately its initial dimen-sions and shape after substantial deformation by a weak stress and release of the stress.(1985)engineered plastic,n—a material that has been made by specific design and through use of particular monomers and monomer sequences to produce a plastic with desired properties,possibly for a specific application.(1991)engineering plastics,n—those plastics and polymeric compo-sitions for which well-defined properties are available such that engineering rather than empirical methods can be used for the design and manufacture of products that require definite and predictable performance in structural applica-tions over a substantial temperature range.epoxy plastics,n—thermoplastic or thermosetting plastics containing ether or hydroxyalkyl repeating units,or both, resulting from the ring-opening reactions of lower molecular weight polyfunctional oxirane resins,or compounds,with catalysts or with various polyfunctional acidic or basic coreactants.D ISCUSSION—Epoxy plastics often are modified by the incorporationof diluents,plasticizers,fillers,thixotropic agents,or other materials.(1985)ethylene plastics,n—plastics based on polymers of ethylene or copolymers of ethylene with other monomers,the ethyl-ene being in greatest amount by mass.(ISO)(1982) expandable plastic,n—a plastic in a form capable of being made cellular by thermal,chemical,or mechanical means. (1985)expanded plastics—See cellular plastic.(1985) extrusion,n—a process in which heated or unheated plastic is forced through a shaping orifice(a die)in one continuously formed shape,as infilm,sheet,rod,or tubing.(1983) fabricating,n—the manufacture of plastic products from molded parts,rods,tubes,sheeting,extrusions,or other forms by appropriate operations such as punching,cutting, drilling,and tapping including fastening plastic parts to-gether or to other parts by mechanical devices,adhesives, heat sealing,or other means.(1978)fiber show,n—strands or bundles offibers not covered by resin which are at or above the surface of a reinforced plastic.(1985)filler,n—a relatively inert material added to a plastic to modify its strength,permanence,working properties,or other quali-ties,or to lower costs.(See also reinforced plastic.)(1978)film,n—in plastics,an optional term for sheeting having a nominal thickness not greater than0.25mm(0.01in.). (1985)fish-eye,n—small globular mass that has not blended com-pletely into the surrounding material.See gel.(1978)fluorocarbon plastic,n—a plastic based on polymers made with perfluoromonomers.D ISCUSSION—When the monomer is essentially tetrafluoroethylene,the prefix TFE is sometimes used to designate these materials.It is preferable to use the accepted abbreviation,PTFE.TFE should not be used by itself to mean PTFE.When the resins are copolymers of tetrafluoroethylene and hexafluoropropylene,the resins may be desig-nated with the prefix FEP.Other prefixes may be adopted to designate otherfluorocarbon plastics.(ISO)(1983)fluorohydrocarbon plastics,n—plastics based on polymers made with monomers composed offluorine,hydrogen,and carbon only.(ISO)(1982)fluoroplastic,n—a plastic based on polymers made from monomers containing one or more atoms offluorine,orcopolymers of such monomers with other monomers,the fluorine-containing monomer(s)being in greatest amount by mass.D ISCUSSION—For specific examples offluoroplastic seefluorocarbonplastic,chlorofluorocarbon plastics,fluorohydrocarbon plastics, and chlorofluorohydrocarbon plastics.(1983)foamed plastics,n—See cellular plastics(the preferred termi-nology).(1983)forming,n—a process in which the shape of plastic pieces such as sheets,rods,or tubes is changed to a desired configuration.D ISCUSSION—The use of the term“forming”in plastics technologydoes not include such operations as molding,casting,or extrusion,in which shapes or pieces are made from molding materials or liquids.(1982)furan plastics—plastics based on furan resins.(ISO)(1982) furan resin,n—a resin in which the furan ring is an integral part of the polymer chain and represents the greatest amount by mass.(ISO)(1983)gate,n—in an injection mold,a constriction in theflow channel between the runner and the mold cavity.(1983) gel,n—(1)a semisolid system consisting of a network of solid aggregates in which liquid is held.(2)the initial jelly-like solid phase that develops during the formation of a resin from a liquid.(3)with respect to vinyl plastisols,gel is a state between liquid and solid that occurs in the initial states of heating,or upon prolonged storage.D ISCUSSION—All three types of gels have very low strengths and donotflow like a liquid.They are soft,flexible,and may rupture under their own weight unless supported externally.(1978)(4)in plasticfilm and sheet,a nodule of plastic material composedof one or more of oxidized,high-molecular-weight,unmelted,non-solvated,or cross-linked material of the same composition as the matrix that,for a variety of reasons,has not blended with the matrix.See fish-eye.D ISCUSSION—Gel in thefilm or sheet is to be distinguished fromcontamination such as particles of dirt,carbon,or lint.(1992)gel point,n—the stage at which a liquid begins to exhibit pseudo-elastic properties.D ISCUSSION—This stage may be detected as the inflection point on aviscosity-time plot.(See gel(2).)(1985)gel time,n—the period of time from the initial mixing of the reactants of a liquid material composition to the time when gelation occurs,as defined by a specific test method.D ISCUSSION—For a material that must be processed by exposure tosome form of energy,the zero time is the start of exposure.(1983) glass,n—an inorganic product of fusion which has cooled to a rigid condition without crystallizing.D ISCUSSION—Term not defined by Committee D20.Definition ap-proved by Committee C14on Glass and Glass Products.See Termi-nology C162.(a)Glass is typically hard and brittle and has a conchoidal fracture.It may be colorless or colored,and transparent to opaque.Masses or bodies of glass may be made colored,translucent,or opaque by the presence of dissolved,amorphous,or crystalline material.(b)When a specific kind of glass is indicated,such descriptive termsasflint glass,barium glass,and window glass should be used following the basic definition,but the qualifying term is to be used as understood by trade custom.(c)Objects made of glass are loosely and popularly referred to asglass;such as glass for a tumbler,a barometer,a window,a magnifier or a mirror.(1978)glassfinish—a material applied to the surface of glassfibers used to reinforce plastics and intended to improve the physical properties of such reinforced plastics over that obtained using glass reinforcement withoutfinish.(1982) glass transition—the reversible change in an amorphous polymer or in amorphous regions of a partially crystalline polymer from(or to)a viscous or rubbery condition to(or from)a hard and relatively brittle one.D ISCUSSION—The glass transition generally occurs over a relativelynarrow temperature region and is similar to the solidification of a liquid to a glassy state;it is not a phase transition.Not only do hardness and brittleness undergo rapid changes in this temperature region but other properties,such as thermal expansibility and specific heat also change rapidly.This phenomenon has been called second order transition, rubber transition and rubbery transition.The word transformation has also been used instead of transition.Where more than one amorphous transition occurs in a polymer,the one associated with segmental motions of the polymer backbone chain or accompanied by the largest change in properties is usually considered to be the glass transition.(1980)glass transition temperature(Tg)—the approximate mid-point of the temperature range over which the glass transi-tion takes place.D ISCUSSION—The glass transition temperature can be determinedreadily only by observing the temperature at which a significant change takes place in a specific electrical,mechanical,or other physical property.Moreover,the observed temperature can vary significantly depending on the specific property chosen for observation and on details of the experimental technique(for example,rate of heating, frequency).Therefore,the observed Tg should be considered only an estimate.The most reliable estimates are normally obtained from the loss peak observed in dynamic mechanical tests or from dialatometric data.(1978)graft copolymer—a copolymer in which polymeric side chains have been attached to the main chain of a polymer of different structure.(1973)gusset,n—(1)a piece used to give additional size or strength in a particular location of an object.(2)the folded-in portion offlattened tubularfilm.(1972) halocarbon plastics—plastics based on resins made by the polymerization of monomers composed only of carbon and a halogen or halogens.(1978)haze—the cloudy or turbid aspect or appearance of an other-wise transparent specimen caused by light scattered from within the specimen or from its surfaces.D ISCUSSION—For the purpose of Test Method D1003,haze is thepercentage of transmitted light which,in passing through the specimen, deviates from the incident beam through forward scatter more than2.5 deg on the average.(1983)heat mark—extremely shallow depression or groove in the surface of a plastic visible because of a sharply defined rim or a roughened surface.(See also shrink mark.)(1978)high density polyethylene plastics,(HDPE)n —those linear polyethylene plastics,g.v.,having a standard density of 0.941g/cm 3or greater.D ISCUSSION —These plastics are usually produced commercially by processes not employing free radical polymerization.Standard density refers to the density of the material molded to a thickness of 1.9mm (0.075in.)using Procedure C of Annex A1of Practice D 4703.high-pressure molding,n —a method of molding or laminat-ing in which the pressure used is greater than 1400kPa (200psi).(1985)hold pressure,n —in molding,the melt pressure during the hold time interval in injection molding.homopolymer,n —a polymer resulting from polymerization involving a single monomer.(1983)hydrocarbon plastics —plastics based on resins made by the polymerization of monomers composed of carbon and hy-drogen only.(1985)hydrolytically degradable plastics,n —See degradable plas-tic.inhibitor,n —a substance used in low concentration which suppresses a chemical reaction.D ISCUSSION —Inhibitors,unlike catalysts,are consumed during the reaction.(1983)injection molding,n —the process of forming a material by forcing it,in a fluid state and under pressure,through a runner system (sprue,runner,gate(s))into the cavity of a closed mold.D ISCUSSION —Screw injection molding and reaction injection molding are types of injection molding.(1983)injection time,n —the time interval from the beginning of screw forward movement until switching over to hold pressure.(1995)insert,n —a part consisting of metal or other material which may be molded into position or may be pressed into the molding after the completion of the molding operation.(ISO)(1978)isotactic,adj —pertaining to a type of polymeric molecular structure containing a sequence of regularly spaced asym-metric atoms arranged in like configuration in a polymer chain.(1985)knit-line,n —See weld-line (the preferred terminology).(1983)knuckle area —in reinforced plastics,the area of transition between sections of different geometry in a filament-wound part.(1985)laminate,9n —a product made by bonding together two or more layers of material or materials.(See also cross lami-nate and parallel laminate.)(ISO)D ISCUSSION —A single resin-impregnated sheet of paper,fabric,or glass mat,for example,is not considered a laminate.Such a single-sheet construction may be called a “lamina.”(See also reinforced plastic.)(1983)lattice pattern —in reinforced plastics,a pattern of filamentwinding with a fixed arrangement of open voids.(1985)lay,n —(1)the length of twist produced by stranding filaments,such as fibers,wires,or roving;(2)the angle that such filaments make with the axis of the strand during a stranding operation.D ISCUSSION —Length of twist of a filament is usually measured as the distance parallel to the axis of the strand between successive turns of the filament.(1985)lay up,n —in reinforced plastics,an assembly of layers of resin-impregnated material ready for processing.(1982)lay up,v —in reinforced plastics,to assemble layers of resin-impregnated material for processing.(1985)let-go,n —an area in laminated glass over which an initial adhesion between interlayer and glass has been lost.(1985)lignin plastics —plastics based on lignin resins.(ISO)(1983)lignin resin —a resin made by heating lignin or by reaction of lignin with chemicals or resins,the lignin being in greatest amount by mass.(ISO)(1983)linear low density polyethylene plastics,(LLDPE)n —those linear polyethylene plastics,q.v.,having a standard density of 0.919to 0.925g/cm 3.D ISCUSSION —These plastics are usually produced commercially by processes not employing free radical polymerization.Standard density refers to the density of the material molded to a thickness of 1.9mm (0.075in.)using Procedure C of Annex A1of Practice D 4703.linear medium density polyethylene plastics,(LMDPE)n —those linear polyethylene plastics,q.v.,having a stan-dard density of 0.926to 0.940g/cm 3.D ISCUSSION —These plastics are usually produced commercially by processes not employing free radical polymerization.Standard density refers to the density of the material molded to a thickness of 1.9mm (0.075in.)using Procedure C of Annex A1of Practice D 4703.linear polyethylene plastics,n —those containing insignificant amounts of long-chain branching but which may contain significant amounts,by design,of short-chain branching.D ISCUSSION —These plastics,usually produced commercially by pro-cesses not employing free radical polymerization,are subcategorized by density level;linear low density polyethylene plastic,linear medium density polyethylene plastic,and high density polyethylene plastic.For differentiation among high molecular versions of these plastics pro-duced commercially by stereo-specific catalysts,see extra-high mo-lecular weight polyethylene plastic and ultra-high molecular weight polyethylene plastic.low density polyethylene plastics,(LDPE)n —those branched polyethylene plastics,q.v.,having a standard density of 0.910to 0.925g/cm 3.D ISCUSSION —These plastics are usually produced commercially by processes employing free radical polymerization.Standard density refers to the density of the material molded to a thickness of 1.9mm (0.075in.)using Procedure C of Annex A1of Practice D 4703.low-pressure molding,n —a method of molding or laminating in which the pressure is 1400kPa (200psi)or less.(1985)lubricant bloom —See bloom.(1982)luminous transmittance,n —the ratio of the luminous flux transmitted by a body to the flux incident upon it.9These definitions are identical with those appearing in Terminology D 907,which were prepared by ASTM Committee D14onAdhesives.。