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高导热石墨烯-碳化硅复合材料的应用

高导热石墨烯-碳化硅复合材料的应用
高导热石墨烯-碳化硅复合材料的应用

High thermal conductivity of graphite ?ber silicon carbide composites for fusion reactor application

L.L.Snead

a,*

,M.Balden b ,R.A.Causey c ,H.Atsumi

d

a

Oak Ridge National Laboratory,Oak Ridge,TN 37831-6138,USA

b

Max-Planck-Institut f €u r Plasmaphysik,Boltzmannstrasse 2,D-85748Garching,Germany

c

Sandia National Laboratory,MS 9402Livermore,CA,USA d

Kinki University,Kowakae 3-4-1,Higashi-Osaka 577-8502,Japan

Abstract

The bene?ts of using CVI SiC/graphite ?ber composites as low tritium retaining,high thermal conductivity com-posites for fusion applications are presented.Three-dimensional woven composites have been chemically vapor in?l-trated with SiCand their thermophysical properties measured.One material used an intermediate grade graphite ?ber in all directions (Amoco P55)while a second material used very high thermal conductive ?ber (Amoco K-1100)in the high ?ber density direction.The overall void was less than 20%.Strength as measured by four-point bending was comparable to those of SiC/SiC composite.The room temperature thermal conductivity in the high conductivity di-rection was impressive for both materials,with values >70W/m K for the P-55and >420W/m K for the K-1100variant.The thermal conductivity was measured as a function of temperature and exceeds the highest thermal con-ductivity of CVD SiC currently available at fusion relevant temperatures (>600°C).Limited data on the irradiation-induced degradation in thermal conductivity is consistent with carbon ?ber composite literature.ó2002Elsevier Science B.V.All rights reserved.

1.Introduction

It is commonly accepted that carbon ?ber composites (CFC ?s)will have unacceptably high tritium reten-tion and signi?cant thermal conductivity reduction for application in fusion power reactors at intermediate temperatures (T <800°C).For higher temperature ap-plications (T >800°C)the thermal conductivity de-gradation is mitigated,but the mechanical property degradation is accelerated,setting CFC useful lifetime into the 10–20dpa range.Recently,the low thermal conductivity of silicon carbide ?ber/silicon carbide ma-trix (SiC f /SiC)composites,especially in the irradiated condition,raises questions regarding their viability as a ?rst wall material.The purpose of this paper is to dem-onstrate,through a basic understanding of the phenom-

enon of tritium retention and thermal conductivity,that a composite material can be engineered with signi?cantly reduced tritium retention with thermal conductivity and mechanical properties which satisfy the current fusion reactor concepts employing SiCcomposites.1.1.Tritium retention

Tritium retention in graphite and silicon carbide are similar in many ways.Both materials have tritium dif-fusion coe?cients that rise to measurable values only at very elevated temperatures [1–3],both materials have negative heats of solution for tritium [1,2],and both have tritium retention characteristics that depend on the crystallite size of the materials [2,4].The di?usion coef-?cient for tritium in graphite as given by Causey [2]is:D ?9:3?10à5exp eà2:8eV =kT Tm 2/s.The di?usion coe?cient for tritium in silicon carbide as given by Causey et al.[5]for beta silicon carbide is:D ?9:8?10à8exp eà1:89eV =kT Tm 2/s.Note the very high acti-vation energy for the di?usion,suggesting

migration

Journal of Nuclear Materials 307–311(2002)

1200–1204

https://www.doczj.com/doc/5b15039793.html,/locate/jnucmat

*

Corresponding author.Tel.:+1-8655749942;fax:+1-8652413650.

E-mail address:sneadll@https://www.doczj.com/doc/5b15039793.html, (L.L.Snead).

0022-3115/02/$-see front matter ó2002Elsevier Science B.V.All rights reserved.PII:S 0022-3115(02)01115-7

controlled by jumps from one trap site to another. Atsumi et al.[1]determined the solubility of hydrogen in graphite to be given by the expression S?6:4?10à5expet0:2eV=kTTatom fraction/atm1=2.Causey et al.[5]reported the solubility of tritium in beta silicon carbide to be1:7?10à7expet0:61eV=kTTatom frac-tion/atm1=2.A negative heat of solution(solubility that decreases with increasing temperature)is an indicator of the chemical a?nity of the hydrogen isotope to the host material.The inward permeation rate of tritium into these materials(product of di?usivity times/solubility) during exposure to hydrogen or tritium gas are among the lowest of all materials.

Atsumi et al.[4]have given direct proof of this in their study showing the apparent hydrogen solubility in graphite to vary inversely with the graphite perfection. Defects on the prism planes also provide a?nite number of very deep traps(%4.3eV)that capture some of the tritium as it migrates along the crystallites.The number of deep traps also varies indirectly with the lattice pa-rameter.Exposure to radiation damage decreases the graphite perfection(decreases the lattice parameter), increasing the apparent solubility and trap density [4,6,7].

It is possible that hydrogen also migrates along the crystal edges of silicon carbide.Evidence for this possi-bility comes from the study of Causey et al.[5]where beta silicon carbide samples with non-uniform crystal sizes were exposed to deuterium gas at elevated tem-peratures.Nuclear reaction pro?ling of the deuterium concentration showed enhanced retention on the sides of the samples with the smaller grains.Unlike graphite, radiation damage does not appear to a?ect the retention of hydrogen in beta silicon carbide[7].At the present time,the reason for this is not understood.However, this immunity to radiation e?ects on trapping gives sil-icon carbide a signi?cant advantage over graphite in minimizing tritium retention.

Fig.1(a)demonstrates that the hydrogen solubility is reduced more than an order of magnitude as the de-gree of graphitization(crystalline perfection)is increased

from50%to80%for T irr’600°C.Moreover,Fig. 1(b)compares the tritium retention of an intermediate quality graphite and two high-quality CFC?s.From these data it is seen that the tritium retention saturates at approximately1000appm for a standard nuclear graphite irradiated at<200°Crange,but apparently saturates at less than100appm for the higher perfection CFC?s.The data of Fig.1(a)and(b)are of particular interest because for typical C/C composites,the degree of graphitization of matrix material is signi?cantly less than that of the highly oriented?bers,indicating that the majority of the tritium resides in the composite matrix. By replacing this(low perfection)graphite matrix with very low hydrogen solubility SiC,the high thermal conductivity of the?bers can still be utilized while the signi?cant tritium retention problem associated with the matrix is avoided.

1.2.Thermal conductivity

Thermal conductivity degradation in graphite and C/ Ccomposites has been very well documented[8]and can decrease by over an order of magnitude at low?uence, depending on the irradiation temperature.This decrease in thermal conductivity typically saturates at a neutron ?uence level between a few tenths and a few dpa,de-pending on irradiation temperature.Above room tem-perature,the process of phonon scattering signi?cantly reduces the thermal conductivity in ceramics and graphite.At very high temperatures(’1000°C)

this Fig.1.(a)E?ect of graphitic perfection on hydrogen solubility. Irradiation temperature was200and600°C[4].(b)E?ect on neutron dose on tritium retention of low and high quality graphite.

L.L.Snead et al./Journal of Nuclear Materials307–311(2002)1200–12041201

process is as e?ective at reducing thermal conductivity as defects associated with high-dose neutron irradiation.A convenient way to compare the susceptibility of materials to irradiation-induced degradation in thermal conductivity is to compare their thermal defect resis-tances.This parameter is de?ned as follows:1=K rd ?1=K irr à1=K non àirr :

For both graphite [9]and most likely silicon carbide,the formation of vacancies and small vacancy clusters will dominate the phonon scattering,hence the thermal conductivity,in the temperature range from 200–1000°C.Fig.2shows the thermal defect resistance parameter for pyrolitic graphite and silicon carbide as a function of irradiation temperature [10–12].For both cases the neutron dose was su?cient to be above,or near,the point of saturation.Near room temperature the thermal defect resistance is about a factor of two less for the graphite,but as temperature is increases the defect re-sistance for the graphite rapidly decreases,while SiC slowly decreases with temperature.This is due to the limited interstitial mobility of SiC(T crit ’300K)[13,14]as compared to graphite (T crit ’20K)[15].To reinforce this point,assuming the data of Fig.2and that thermal defect resistance was dominant,the thermal conductivity at 1000°Cwould be ’100W/m K for graphite and ’20W/m K for silicon carbide.Clearly,the e?ect of irradi-ation on the thermal conductivity is more severe for SiC over the temperature range of interest to fusion.1.3.Mechanical properties

Though development of this system has been limited,some authors [16–23]have reported these materials to have similar or higher strength as compared to SiC

matrix/SiC?ber composites.Moreover,the ?exural fracture toughness as measured by the area under the curve beyond macroscopic matrix micro-cracking is su-perior for the graphite ?ber composites.A review on the subject of CVI SiC composites is given by Lara-Curzio [24].

2.Experimental

Composite preforms were composed of a three-dimensional,unbalanced weave of Amoco K1100and P55graphite ?bers.Both ?bers are pitch derived from the same precursor,but have di?erent graphitization tem-peratures,hence di?erent degrees of crystalline align-ment,perfection and thermal conductivity.The P55?ber was woven in 2-k tows in the x -and y -directions while six 2-k tows of K1100were stitched through the or-thogonal weave in the z -direction (de?ned as the K1100composite).A second perform with the same architec-ture used P-55?bers in all directions (de?ned as the P55composite).Preforms were rigidized with polymethyl-methacrylate.The overall ?ber volume fraction was 43.9%of which 7.1%was in the x -and y -directions and 85.7%was in the z direction.The graphite preform was machined into 4.45cm diameter,1.27cm thick discs which were mounted in graphite holders for in?ltration.The preform was then heated to 350°Cin an argon ?ow gas to burn out the PMMA binder.Preforms were then in?ltrated with SiCusing standard isothermal chemical vapor in?ltration and forced-?ow chemical vapor in?l-tration (FCVI)[25].Room temperature bend testing was carried out on 0:3?0:4?5:0cm 3bars with an upper and lower span of 1.9and 3.8cm,respectively.Thermal di?usivity was measured using a ?ash technique and conductivity calculated using the composite density and speci?c heat.A graphite standard was measured before each measurement ensuring the thermal di?usivity ap-paratus was operating to within a few percent error.The temperature dependent speci?c heat was calculated as-suming the rule of mixtures.Irradiation was carried out in the high ?ux isotope reactor in peripheral tube rabbit capsules at a ?ux of ’8?1018n/m 2(E >0:1MeV)and calculated sample temperatures between 400and 800°C.The samples were 6mm in diameter and thickness.The axis of the samples was along the composite high con-ductivity direction.Atmosphere of the irradiation cap-sules was static helium.

3.Results and discussion

The potential for this composite in fusion applica-tions is that it o?ers a high thermal conductivity com-posite with signi?cantly lower tritium retention than the advanced carbon/carbon composites (C/C ?s)

currently

Fig.2.Thermal defect resistance of pyrolitic graphite and sili-con carbide for doses above saturation [10–12].

1202L.L.Snead et al./Journal of Nuclear Materials 307–311(2002)1200–1204

considered for plasma facing components.The thermal conductivity of the composite system can be engineered to be isotropic or optimized for high conductivity in a single direction,as needed.The three-dimensional CVD SiC/K1100composite fabricated for this study yielded reasonably good strength and,from an analysis of the ?exure curves[26]and fracture surfaces,possessed a fair amount of toughness.In the major?ber direction,the four-point bend strength was(267?28)MPa which is comparable to CVI SiC/SiC?ber materials[24]. Strength of bend bars across the major?ber direction would be considerably reduced due to the reduced fraction of(P55)?bers in this orientation.

The thermal conductivity of both SiC/graphite pro-duced in this study is given in Fig.3.Also shown is the thermal conductivity of a very high quality monolithic CVD SiC materials produced by Morton(now Rohm Haas),and the transverse thermal conductivity of an FCVI SiC/Type S Nicalon composite.As expected,due

to the signi?cantly higher thermal conductivity of the graphite?bers(’950and’120W/m K at ambient for K1100and P55,respectively)as compared to the SiC ?ber(’15W/m K at ambient),the SiC/graphite com-posites have a much higher thermal conductivity in their major?ber direction.In their minor?ber direction,the thermal conductivity was’15W/m K,or about the same as the SiC/SiC composite.At approximately200°C,the thermal conductivity of the K1100composite exceeds that of the high quality CVD SiC while the P55 composite approaches this value at the highest temper-atures measured.The?lled points represent measured di?usivity data in Fig.3.

The e?ect of low-dose irradiation at400–800°Con the P55/SiCcomposite is given in Fig.4.Dimensional measurements yielded data consistent with irradiation-induced swelling of SiC.As expected,a large decrease in thermal conductivity has occurred for the three tem-perature/dose levels studied,with the largest decrease occurring for the higher dose,lower temperature speci-mens.As the dose is below that of saturation,and the data set is very limited,a quantitative comparison of the thermal conductivity degradation of the P55composite with models and previous data from the graphite liter-ature is not appropriate.However,from the data,the thermal defect resistance is comparable to,or perhaps larger,than expected from the literature on pyrolitic graphite.For the case of the0.5dpa irradiation,the thermal conductivity should be approaching saturation, indicating that the P55material may possess more than twice the’15W/m K minimum value of irradiated thermal conductivity called for in present day ARIES and TAURO design study.However,signi?cant further study on the e?ect of irradiation is required.In partic-ular,the thermal conductivity and the e?ects on non-isotropic swelling of the graphite?ber must be studied up to higher damage levels.As the thermal conductivity in these materials is carried primarily by the?bers, cracking of the?bers due to axial shrinkage and the e?ect of this on the thermal conductivity will need to be understood.

4.Conclusions

The potential of a silicon carbide matrix,graphite ?ber composite for special purpose application in fusion systems has been presented.It is speculated,based on previous work on tritium retention in graphite and SiC, that this system will have signi?cantly less tritium re-tention than present day high-quality CFC?s.For the two materials of this study,the thermal conductivity at the fusion relevant operating temperature of550°Cwas ’90W/m K(P55?ber composite)and150W/m

K Fig.4.E?ect of low-dose irradiation at400–800°Con the thermal conductivity of SiC/graphite

composite.

Fig.3.Temperature dependent thermal conductivity of non-

irradiated monolithic SiC,SiC/SiC and SiC/graphite compos-

ites.

L.L.Snead et al./Journal of Nuclear Materials307–311(2002)1200–12041203

(K1100?ber composite.)This considerably exceeds the thermal conductivity of the present day CVI SiC/SiC composites at that temperature(’12W/m K).The ef-fects of low-dose irradiation on thermal conductivity indicate a signi?cant reduction in thermal conductivity, as expected from the graphite radiation e?ects literature. However,these preliminary data indicate the thermal conductivity still signi?cantly exceeds the minimum value called for in design studies. Acknowledgements

The authors would like to thank Marie Williams for assistance with thermal di?usivity measurements. Research sponsored by the O?ce of Fusion Energy Sciences,US Department of Energy under contract DE-AC05-00OR22725with UT-Battelle,LLC. References

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石墨烯聚乳酸复合材料

Preparation of Polylactide/Graphene Composites From Liquid-Phase Exfoliated Graphite Sheets Xianye Li,1Yinghong Xiao,2Anne Bergeret,3Marc Longerey,3Jianfei Che1 1Key Laboratory of Soft Chemistry and Functional Materials,Nanjing University of Science and Technology, Nanjing210094,China 2Jiangsu Collaborative Innovation Center of Biomedical Functional Materials,Jiangsu Key Laboratory of Biomedical Materials,College of Chemistry and Materials Science,Nanjing Normal University, Nanjing210046,China 3Materials Center,Ales School of Mines,30319Ales Cedex,France Polylactide(PLA)/graphene nanocomposites were pre-pared by a facile and low-cost method of solution-blending of PLA with liquid-phase exfoliated graphene using chloroform as a mutual solvent.Transmission electron microscopy(TEM)was used to observe the structure and morphology of the exfoliated graphene. The dispersion of graphene in PLA matrix was exam-ined by scanning electron microscope,X-ray diffrac-tion,and TEM.FTIR spectrum and the relatively low I D/I G ratio in Raman spectroscopy indicate that the structure of graphene sheets(GSs)is intact and can act as good reinforcement fillers in PLA matrix.Ther-mogravimetric analysis and dynamic mechanical analy-sis reveal that the addition of GSs greatly improves the thermal stability of PLA/GSs nanocomposites.More-over,tensile strength of PLA/GSs nanocomposites is much higher than that of PLA homopolymer,increasing from36.64(pure PLA)up to51.14MPa(PLA/GSs-1.0). https://www.doczj.com/doc/5b15039793.html,POS.,35:396–403,2014.V C2013Society of Plastics Engineers INTRODUCTION Polylactide(PLA),a renewable,sustainable,biode-gradable,and eco-friendly thermoplastic polyester,has balanced properties of mechanical strength[1],thermal plasticity[2],and compostibility for short-term commod-ity applications[3,4].It is currently considered as a promising polymer for various end-use applications for disposable and degradable plastic products[5–8].Never-theless,improvement in thermal and mechanical proper-ties of PLA is still needed to pursue commercial success. To achieve high performance of PLA,many studies on PLA-based nanocomposites have been performed by incorporating nanoparticles,such as clays[9,10],carbon nanotubes[11–13],and hydroxyapatite[14].However, research on PLA-based nanocomposites containing gra-phene sheets(GSs)or graphite nanoplatelets has just started[15–17].GSs exhibit unique structural features and physical properties.It has been known that GSs have excellent mechanical strength(Young’s modulus of1,060 GPa)[18],electrical conductivity of104S/cm[19],high specific surface area of2,630m2/g[20],and thermal sta-bility[21].Polymer nanocomposites based on graphene show substantial property enhancement at much lower fil-ler loadings than polymer composites with conventional micron-scale fillers,such as glass[22]or carbon fibers [23],which ultimately results in lower filler ratio and simple processing.Moreover,the multifunctional property enhancement of nanocomposites may create new applica-tions of polymers. However,the incorporation of graphene into PLA matrix is restricted by cost and yield.Although the weak interactions that hold GSs together in graphite allow them to slide readily over each other,the numerous weak bonds make it difficult to separate GSs homogeneously in sol-vents and polymer matrices[24].Many methods have been reported for exfoliation of graphite,such as interca-lation with alkali metals[25]or oxidation in strong acidic conditions[26–29].Recently,exfoliation of graphite in liquid-phase was found to be able to give oxide-free GSs with high quality and yield at relatively low cost[30–35]. Correspondence to:Y.H.Xiao;e-mail:yhxiao@https://www.doczj.com/doc/5b15039793.html, or J.F.Che; e-mail:xiaoche@https://www.doczj.com/doc/5b15039793.html, Contract grant sponsor:Specialized Research Fund for the Doctoral Program of Higher Education of China;contract grant number: 20123219110010;contract grant sponsor:Natural Science Foundation of Jiangsu Province of China;contract grant number:BK2012845;contract grant sponsors:Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),contract grant sponsor:Financial support for short visit from Ales School of Mines,France. DOI10.1002/pc.22673 Published online in Wiley Online Library(https://www.doczj.com/doc/5b15039793.html,). V C2013Society of Plastics Engineers POLYMER COMPOSITES—2014

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说明 1、课程论文要有题目、作者姓名、摘要、关键词、正文及参考文献。论文题目由研究生结合课程所学内容选定;摘要500字以下,博士生课程论文要求有英文摘要;关键词3~5个;参考文献不少于10篇,并应有一定的外文文献。 2、论文要求自己动手撰写,如发现论文是从网上下载的,或者是抄袭剽窃别人文章的,按作弊处理,本门课程考核成绩计0分。 3、课程论文用A4纸双面打印。字体全部用宋体简体,题目要求用小二号字加粗,标题行要求用小四号字加粗,正文内容要求用小四号字;经学院同意,课程论文可以用英文撰写,字体全部用Times New Roman,题目要求用18号字加粗;标题行要求用14号字加粗,正文内容要求用12号字;行距为2倍行距(方便教师批注);页边距左为3cm、右为2cm、上为2.5cm、下为2.5cm;其它格式请参照学位论文要求。 4、学位类别按博士、硕士、工程硕士、MBA、MPA等填写。 5、篇幅、内容等由任课教师提出具体要求。

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论文 题目: 石墨烯复合材料的制备 及其性能研究进展学生姓名: 学号: 院(系):化工与制药工程系专业班级: 指导教师: 职称: 201 年月

石墨烯复合材料的制备及其性能研究进展 摘要: 石墨烯以其优异的性能和独特的二维结构成为材料领域研究热点。本文综述了石墨烯的制备方法并分析比较了各种方法的优缺点, 简单介绍了石墨烯的力学、光学、电学及热学性能。基于石墨烯的复合材料是石墨烯应用领域中的重要研究方向, 本文详细介绍了石墨烯聚合物复合材料和石墨烯基无机纳米复合材料的制备及应用,以及石墨烯复合材料的展望。 关键词:石墨烯;制备;性能;复合材料

Research Progress on Preparation and properties of graphene composite materials Abstract: Graphene has become a hot research field of material for its excellent performance and unique two-dimensional structure. This paper summarizes the method for preparing graphene and compared the advantages and disadvantages of various methods,introduces the mechanics,graphene optical,electrical and thermal properties. Composite materials based on graphene is an important research direction in the field of application of graphene,this paper introduces the preparation and application of graphene polymer composites and graphene based inorganic nano composite material,and the prospect of graphene composite materials. Key words:graphene;preparation;properties;composite materials

树脂石墨烯复合材料

石墨烯反应 1、加氢反应 2、与重氮化合物反应,之后与三氮唑化合物(苯并三氮唑)环加成反应 3、与碳烯反应 4、与芳炔化合物反应(生成芳基三氟甲磺酸三甲硅酯) 5、与四氰乙烯反应 6、与偶氮二甲亚胺反应 7、与氟化的苯基氮化合物反应

经还原的氧化石墨烯反应 1、与苯基重氮衍生物反应,之后与三氮唑化合物进一步反应 2、与氨基化合物反应(苯乙胺) 3、纳米颗粒负载 4、一 5、与苯基重氮衍生物反应,之后与2-溴丙酸乙酯反应,再与苯乙炔反应

1、催化石墨化,考虑其他催化剂的可能性 2、催化石墨化后直接添加到树脂中,考察合成材料的性能 3、催化石墨化后除去无定型碳添加到树脂中,考察合成材料的性能 4、催化石墨化后酸处理后制成石墨烯,再添加到树脂中 5、热固性树脂的种类 6、热塑性树脂的种类 尿醛树脂与石墨烯、氧化石墨、石墨复合 以氯化铵为固化剂,常温固化时间大概4-5小时。 脲醛树脂 尿素与甲醛反应得到的聚合物。又称脲甲醛树脂。英文缩写UF。加工成型时发生交联,制品为不溶不熔的热固性树脂。固化后的脲醛树脂颜色比酚醛树脂浅,呈半透明状,耐弱酸、弱碱,绝缘性能好,耐磨性极佳,价格便宜,但遇强酸、强碱易分解,耐候性较差。 基本介绍 脲醛树脂一般为水溶性树脂,较易固化,固化后的树脂无毒、无色、耐光性好,长期使用不变色,热成型时也不变色,可加入各种着色剂以制备各种色泽鲜艳的制品。 脲醛树脂坚硬,耐刮伤,耐弱酸弱碱及油脂等介质,价格便宜,具有一定的韧性,但它易于吸水,因而耐水性和电性能较差,耐热性也不高。 用途:可用于耐水性和介电性能要求不高的制品,如插线板、开关、机器手柄、仪表外壳、旋纽、日用品、装饰品、麻将牌、便桶盖,也可用于部分餐具的制造。 包装:大口塑料桶或铁桶,净重20kg。 储运:存于阴凉通风处,储存时间自生产日期起一个月,超过储存期,经检验合格后仍可使用。 它能在酸性介质中固化,常用的固化剂有氯化铵、草酸、邻苯二甲酸、硫脲等。产物需在中性条件下才能贮存。线性脲醛树脂以氯化铵为固化剂时可在室温固化。模塑粉则在130~160℃加热固化,促进剂如硫酸锌、磷酸三甲酯、草酸二乙酯等可加速固化过程。脲醛树脂主要用于制造模压塑料,制造日用生活品和电器零件,还可作板材粘合剂、纸和织物的浆料、贴面板、建筑装饰板等。由于其色浅和易于着色,制品往往色彩丰富瑰丽。 1、脲醛树脂胶的调制使用之前在胶料中要加入氯化铵,其作用是使胶料凝固速度加快,但 要注意用量适当,加少了固化时间太长,不利施工操作;加多了胶会发脆,胶接质量就不好。 根据经验,以100克脲醛树脂而言,在气温10℃以下时,一般应加2.5-3克的氯化铵,而在30℃的气温时,只要加入1历就够了。在胶合木板时,有时在胶料中还加入5-10%的黄豆粉或面粉(粉料不能有粒状,要过100目筛),目的是增加粘稠度,防止过量的胶液渗入木

高分子石墨烯纳米复合材料的前沿与趋势

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