Journal of Colloid and Interface Science300(2006)
279–285
https://www.doczj.com/doc/c316538900.html,/locate/jcis
Synthesis of?exible silica aerogels using methyltrimethoxysilane
(MTMS)precursor
A.Venkateswara Rao a,?,Sharad D.Bhagat a,Hiroshi Hirashima b,G.M.Pajonk c
a Air Glass Laboratory,Department of Physics,Shivaji University,Kolhapur416004,Maharashtra,India
b Faculty of Science and Technology,Keio University,3-14-1,Hiyoshi,Kohoku-ku,Yokohama223-8522,Japan
c Laboratoire d’Application de la Chimie a l’Environnement,UniversitéClaude Bernar
d Lyon1,69622Villeurbann
e Cedex,France
Received1October2005;accepted19March2006
Available online27March2006
Abstract
The experimental results on the synthesis of?exible and superhydrophobic silica aerogels using methyltrimethoxysilane(MTMS)precursor by a two-step(acid–base)sol–gel process followed by the supercritical drying,are reported.The effects of various sol–gel parameters on the ?exibility of the aerogels have been investigated.The aerogels of different densities were obtained by varying the molar ratio of MeOH/MTMS (S)from14to35,with lower densities for larger S values.It has been observed that the Young’s modulus(Y)decreased from14.11×104to
3.43×104N/m2with the decrease in the density of the aerogels from100to40kg/m3.Simultaneously,the aerogels are superhydrophobic with
a contact angle as high as164?.The superhydrophobic aerogels are thermally stable up to a temperature of530K,above which they become hydrophilic.The aerogels have been characterized by bulk density,percentage volume shrinkage,and porosity measurements.The microstructures of the aerogels have been studied using the transmission electron microscopy(TEM).The Young’s modulus of the aerogels has been determined by an uniaxial compression test.The variation of physical properties of the aerogels has been explained by taking into consideration the hydrolysis, condensation reactions,the resulting colloidal clusters and their network formation.
?2006Published by Elsevier Inc.
Keywords:Silica aerogels;Elastic properties;TEM;Superhydrophobicity;Flexible aerogels
1.Introduction
Silica aerogels are sol–gel-derived materials consisting of interconnected nano-particle building blocks,which form an open and highly porous three-dimensional silica network.Typ-ical silica aerogels have high surface area(～1000m2/g),high optical transmission(～93%),low density(40kg/m3)and low thermal conductivity(0.02W/mK)[1–4].These features have led the aerogels for various applications such as super thermal insulation[5,6],acoustic insulation[7],in Cerenkov radiation detectors[8,9],low dielectric constant aerogel?lms in ultra large scale integrated circuits[10,11],superhydrophobic aero-gels for oil-spill cleanup[12],in catalysis[13],and inertial *Corresponding author.
E-mail address:raouniv@https://www.doczj.com/doc/c316538900.html,(A.Venkateswara Rao).con?nement fusion(ICF)targets in thermonuclear fusion re-actions[14].
Despite having these fascinating properties,the aerogels have major drawbacks that they are fragile,brittle and mois-ture sensitive,which limit their applications in various?elds. Due to the fragility and the brittleness,aerogels easily break and become into pieces and powder with the application of a small stress.Therefore,in the present studies,attempts have been made to synthesize highly?exible and superhydrophobic silica aerogels using methyltrimethoxysilane(MTMS)precur-sor by a two-step acid–base sol–gel process[15].The aerogels consist of cross-linked network of silica polymer chains ex-tended in three dimensions as can be seen from Fig.1.Due to the presence of non-polar alkyl groups(i.e.methyl)attached to the silica polymer chains,the inter-chain cohesion is minimized resulting in the elastic and?exible three-dimensional network. Also,the higher dilution of the MTMS precursor with methanol solvent yielded silica network with a low degree of polymeriza-
0021-9797/$–see front matter?2006Published by Elsevier Inc. doi:10.1016/j.jcis.2006.03.044
280 A.Venkateswara Rao et al./Journal of Colloid and Interface Science300(2006)
279–285
Fig.1.Transmission electron micrograph of silica aerogel showing three-dimensional cross-linked network of silica chains.
tion exhibiting higher?exibility.Whereas,for lower dilution of the MTMS precursor,an extensive polymerization resulted in dense and rigid structures.Because of the new property,i.e.?exibility in the aerogel,it can be bent to any shape and acts as
a good shock absorber as well.
2.Experimental procedures
2.1.Sample preparation
Silica aerogels were produced by a two-step,acid–base,cat-alyzed sol–gel process followed by the supercritical drying.The chemicals used were:methyltrimethoxysilane(MTMS,H3C–Si–(OCH3)3)and ammonium hydroxide(NH4OH)of purum grades(from Fluka Company,Switzerland),methanol(MeOH, CH3OH)and oxalic acid(C2H2O4)of ExcelR and SQ grades, respectively(from Qualigens Company,India).Double distilled water was used to prepare both the acidic and basic catalysts.
Silica alcosols were prepared in a150-ml beaker in two steps(acidic and basic):(i)by mixing and stirring the methyltri-methoxysilane(MTMS),methanol(MeOH)and water(half of the total amount)in the form of oxalic acid catalyst,for30min, and(ii)after24h,the base catalyst(NH4OH)in the form of H2O(the remaining half amount)was added drop by drop while stirring for30min.The total molar ratio of H2O/MTMS was kept constant at8.The molar ratio of MeOH/MTMS(S)was varied from14to35.The oxalic acid catalyst and NH4OH cat-alyst concentrations were varied from0.0005to0.1M and6 to13.36M,respectively.The sols were transferred to Pyrex test tubes of15mm outer diameter and125mm height.The test tubes were made air-tight using wooden corks and kept for gelation at300K.After the sols were set,methanol was added over the gels in order to prevent shrinkage and cracks. The alcogels were aged for two days at300K.Silica aero-gels were obtained by the supercritical drying of the alcogels (at538K and10MPa)in an autoclave of600ml capacity(Parr
Instrument Company,Moline,IL,USA).An excess amount of
methanol(MeOH)was added into the autoclave(total?lling
of the autoclave with MeOH is25%by the volume including
in the gels).After reaching the temperature and pressure well
above the critical points of methanol solvent(T c～516K and P c～7.9MPa),the methanol vapors were released from the autoclave and?nally?ushed with0.3MPa dry nitrogen.The
autoclave was then cooled to an ambient temperature and the
aerogels were taken out for characterization.
2.2.Methods of characterization
The bulk densities of the aerogels were calculated by their
mass to volume ratios.The percentage of porosity(P%)of the
aerogels was calculated using the equation:
(1) P%=
1?
ρb
ρs
×100,
whereρb is the bulk density andρs is the skeletal density of the
aerogels which was measured using helium pycnometry and its
value was found to be1900kg/m3.The percentage of volume
shrinkage(V s%)was determined from the change in the vol-
umes of the alcogel and the aerogel using the equation:
(2) V s%=
1?
V
V1
×100,
where V is the volume of the aerogel and V1is the volume of
the alcogel.
To quantify the degree of hydrophobicity,the contact angle
(θ)of a water droplet placed on the hydrophobic aerogel sur-
face,was calculated using the equation[16]:
(3) tan(θ/2)=(2h/W),
where the base contact length W and height h of the droplet
were measured using a traveling microscope.Also,the contact
angle(θ)was measured by contact angle meter(Tantec Com-
pany,USA).Good agreement has been observed by both the
methods in the measurement ofθ.
The microstructure of the aerogels was studied using the
transmission electron microscope(TEM,Philips,Tecnai F20
model).The thermal stability of the hydrophobic aerogels was
investigated by heating them in a furnace at various tempera-
tures ranging from320to773K.Here,the term thermal stabil-
ity refers to the threshold temperature up to which the aerogel
retains its hydrophobic property,and above which it becomes
hydrophilic.
The elastic constant called the Young’s modulus(Y)or mod-
ulus of elasticity,is a measure of hardness,stiffness,rigidity(or
softness,?exibility,or pliability)of the solid.It is also de?ned
as the resistance to any deformation in the solids.It means that
the lesser the value of Y,the more?exible is the solid.The
Young’s modulus(Y)of the aerogels has been determined by
an uniaxial compression test as shown in Fig.2.In this test,the
aerogel sample under the testing was kept in a glass tube?xed
with a rigid support and having a little bigger diameter than that
of the aerogel sample.Various loads(e.g.,0.01,0.02,0.03kg,
A.Venkateswara Rao et al./Journal of Colloid and Interface Science 300(2006)279–285
281
Fig.2.Schematic diagram of the experimental set-up for the Young’s modulus measurements of the silica aerogels.A:vertical axis;B:platform for the ap-plication of the stress;C:silica aerogel cylinder;D:?at bottom surface; L :change in length after the application of the stress.
etc.)were placed on the cylindrical aerogel samples and as a result,the aerogel undergoes compression which was charac-terized by measuring the corresponding change in length ( L)using the traveling microscope with an accuracy of ±0.0001m.The graphs of the change in length ( L)against the mass ap-plied,m ,were plotted and the slopes ( L/m )of these graphs were used to calculate the Young’s modulus of the aerogels by using the equation:
(4)Young’s modulus (Y )=mgL/πr 2 L =(Lg/πr 2)/slope ,where m is the mass placed on the aerogel sample,g is the ac-celeration due to gravity.L is the original length of the aerogel before deformation and r is the radius of the aerogel.
The root mean square (RMS)error values have been mea-sured using the formula:(5) x ?ˉx 2 5 1/2
,where x and ˉx
represent the actual and mean values,respec-tively.The number of samples used for each measurement are 5.3.Results and discussion
Generally,hydrophilic or hydrophobic silica aerogels were produced by the sol–gel process and supercritical drying of sil-ica alcogels based on the organosilane compound precursors and co-precursors of the type R n SiX 4?n (where R =alkyl or aryl or vinyl groups,X =Cl or alkoxy groups,n =0to 3)[17].Therefore in the present studies we have selected the tri-functional organosilane compound of the type R 1SiX 3,namely the methyltrimethoxysilane (MTMS,H 3C–Si–(OCH 3)3)with an idea that both the methyl and the methoxy groups are the smallest among all the alkyl and alkoxy groups which would therefore facilitate the hydrolysis and condensation reactions leading to the superhydrophobic and ?exible aerogels.We have not tried the chloro-compounds because they corrode the auto-clave systems.
Each monomer of the MTMS precursor has one non-hydro-lyzable methyl group (CH 3)and three hydrolyzable methoxy
groups (OCH 3).The three methoxy groups undergo hydrolysis and condensation reactions as per the following chemical reac-tions:Hydrolysis:
(6)
Condensation:
(7)
As the condensation and hence the polymerization progresses,the number of hydrophobic ≡Si–CH 3groups increases com-pared to the number of hydrophilic ≡Si–OH groups leading to an inorganic–organic hybrid silica network which is superhy-drophobic and highly ?exible.
We have used both the single-stage (base catalyzed)and two-stage (acid–base catalyzed)sol–gel processes.In the single-stage process,the condensation takes place before the hydrol-ysis is fully completed and therefore the network formation is not continuous leading to less ?exible aerogels (less than 5%,compressible by volume).On the other hand,in the two-stage process,?rst the hydrolysis reaction is complete under the acidic conditions and then,after 24h when the base catalyst is added,the condensation takes place leading to the build-up of systematic,complete and continuous network formation leading to highly ?exible aerogels with compression as high as around 60%by volume.
3.1.Effect of MeOH/MTMS molar ratio (S)
The effect of MeOH/MTMS molar ratio (S)on the elastic and other physical properties of the silica aerogels has been studied by keeping the molar ratio of H 2O/MTMS constant at 8.The H 2O was added in the form of oxalic acid and am-monium hydroxide.The oxalic acid (C 2H 2O 4)and ammonium hydroxide (NH 4OH)catalyst concentrations were kept constant at 0.001and 10M,respectively.It has been observed that the gelation time increased from 2to 16h with an increase in S value from 14to 35.This is due to the fact that the increase in the S value increases the separation between the MTMS monomers and also between the reacting silica oligomers in the sol and hence the gelation time increased [18].All the aerogel samples are opaque.
The Young’s moduli (Y )of the aerogels vary with the bulk density.It has been observed that with an increase in S value from 14to 35,the volume shrinkage and hence the bulk den-sity of the aerogels decreased from 28to 7%and from 100to 40kg /m 3,respectively.Fig.3shows the variations of the change in length ( L )against the mass (m)applied for the cal-culation of Y .The Y was found to decrease from 14.11×104
282 A.Venkateswara Rao et al./Journal of Colloid and Interface Science300(2006)
279–285
Fig.3.Plots of change in length against mass applied for the silica aerogels prepared at various MeOH/MTMS molar ratios.
to3.0×104N/m2for S values of14and35,respectively,re-sulting in an increase in the?exibility of the aerogels.Figs.4a and4b show the maximum possible bending of the aerogels (further bending resulted in breaking of the aerogel samples) prepared at two different S values of28and35,respectively. It is clearly seen from Fig.4that the aerogel with S=35 can be bent to a greater extent than the aerogel with S=28. Figs.5a and5b show the transmission electron micrographs of the aerogel samples prepared at two different S values of14 and35,respectively.Since the silica chains of the aerogel with S=35are quite separated from each other and large empty spaces(pores)are seen in the network,the aerogel undergoes more?exibility when the stress is applied.However,if the S value is decreased,i.e.for S=14,the degree of polymerization increased and the extensive cross-linking in three dimensions resulted in the rigid structure leading to less?exibility of the aerogels.
Keeping this in view,to obtain the aerogels with the low Young’s modulus,low density,less volume shrinkage,the MeOH/MTMS molar ratio was kept at35for further experi-ments.
3.2.In?uence of acid and base catalyst concentrations
Generally,in the case of single-step sol–gel process,the gelation time increases with increase in the solvent amount (methanol in the present case)in the sol.This problem of longer gelation time was overcome by using the two-step acid–base sol–gel process.The effect of oxalic acid concentration(A)on the physical and elastic properties of the silica aerogels was studied by varying it from0.0005to0.1M.The S and the NH4OH catalyst concentration were kept constant at35and 10M,respectively.It was observed that the gelation time
de-
(a)
(b)
Fig.4.Flexible silica aerogels prepared at two different MeOH/MTMS molar ratios:(a)S=28and(b)S=35.
creased from16to8h with an increase in the A value from 0.0005to0.1M.This is due to the fact that the increase in A value increases the rate of hydrolysis reaction resulting in the faster gelation[19].
The elastic property measurements revealed that the Young’s modulus(Y)of the aerogels decreased from6.2×104to 3.4×104N/m2with an increase in A value from0.0005to 0.01M.As described in the earlier section,the graphs of the change in length against the mass applied were plotted(Fig.6) to determine the Young’s moduli of the aerogels using Eq.(4). The decrease in the Y can be explained by taking into consid-eration the microstructure of the aerogels.Figs.7a and7b show the transmission electron micrographs of the aerogel samples prepared at two different A values of0.0005and0.01M,re-spectively.It is clearly seen from Fig.7that the silica network
A.Venkateswara Rao et al./Journal of Colloid and Interface Science 300(2006)279–285
283
(a)
(b)
Fig.5.Transmission electron micrographs of MTMS based aerogels prepared with (a)S =14and (b)S =35.
consists of larger particles and pores and the network is less connected for A =0.0005M,and whereas for A =0.01M,the network consists of smaller silica particles and pores with well connected network.Moreover,the bulk density was also found to decrease from 61to 42kg /m 3with increase in the A value from 0.0005to 0.01M.
Therefore,the Young’s modulus (Y )decreased with in-creased oxalic acid concentration (A).Fig.8shows the three states of the ?exible aerogel sample,prepared with A =0.01M:(a)without stress,(b)with an applied stress,and (c)after re-leasing the applied stress.From Fig.8,it is clear that the aerogel sample could be compressed up to around 60%of its volume and regained its original dimension after the stress
is
Fig.6.Plots of change in length against mass applied for the silica aerogels as a function of oxalic acid concentration (A).
released.The experiments on the repeated compression and re-expansion of the aerogels were carried out at least 20times and the elastic properties (the Young’s moduli)have been found to be the same.In addition,it has been observed that the aero-gel maintain the same microstructural properties even after 20times compression and re-expansion.This has been con?rmed by the TEM studies before and after the load was applied and therefore aerogel properties do not degrade after bending or compression.The physical properties are quite reproducible be-cause the aerogels have both the inorganic and organic compo-nents.Each monomer of MTMS contains one non-hydrolyzable organometallic ≡Si–CH 3(R)group leading to the R/Si ratio of 1.Therefore,the ?nal aerogel contains 75%oxide content (i.e.SiO 1.5)and 25%carbon content (i.e.CH 3groups)result-ing in superhydrophobicity (contact angle 164?)and ?exibility (the Young’s modulus ～104N /m 2).
The effect of base catalyst concentration (B)on the physical properties of the silica aerogels has also been studied by vary-ing it from 6to 13.3M.It was observed that for B <10M,the gel could not be obtained because of the sedimentation due to an insuf?cient base catalyst for the complete condensation.For the B >10M,the volume shrinkage and hence the bulk density of the aerogels increased from 20to 30%and from 45to 63kg /m 3,respectively.The volume shrinkage and the bulk density were found to be optimum at B =10M.3.3.Hydrophobicity and thermal stability of the aerogels The precursor,i.e.MTMS,used in the present studies,con-tains one hydrolytically stable methyl group,which is respon-sible for the hydrophobicity in the silica aerogels [20].The
284 A.Venkateswara Rao et al./Journal of Colloid and Interface Science 300(2006)
279–285
(a)
(b)
Fig.7.Transmission electron micrographs of MTMS based aerogels prepared with (a)A =0.0005M and (b)A =0.01M.
hydrophobicity was characterized by measuring the contact an-gles (θ)of the water droplet placed on the aerogel surfaces under investigation.The contact angle (θ)measurements re-vealed that all the aerogels are superhydrophobic with θvalues ranging from 158?to 164?.
The alkyl groups (e.g.,methyl in the present studies)respon-sible for the hydrophobicity are thermally stable up to a thresh-old temperature of 530K.Above this temperature they get de-tached from the surface making it hydrophilic.This threshold temperature for the methyl groups was investigated by heat-ing the aerogels up to temperature of 773K and testing them with water.It has been observed that the MTMS based aero-gels are thermally stable up to a temperature of 530K
and
Fig.8.A photograph showing the three states of the ?exible aerogel sample:(a)without stress,(b)with stress,(c)after releasing the applied stress.
above which the aerogels become hydrophilic and absorb wa-ter.
4.Conclusions
Highly ?exible and superhydrophobic silica aerogels could be obtained using methyltrimethoxysilane (MTMS)precursor by two-step acid–base sol–gel process for the molar ratio of MTMS:MeOH:H 2O at 1:35:8,respectively.The Young’s mod-ulus of the aerogel increased with an increase in the bulk den-sity.Very high dilution of the MTMS precursor in the methanol solvent (ten times)and the presence of non-polar methyl groups in the silica polymer chains resulted in the ?exible silica aero-gels with compressibility as high as ～60%of the original length.The MTMS based aerogels were superhydrophobic with water contact angle as high as 164?.The hydrophobic aerogels were found to be thermally stable up to a temperature of 530K.Since the aerogels are highly compressible,large volumes of the aerogels can easily be transported.Acknowledgments
The authors are grateful to the Department of Science and Technology (DST),New Delhi,Government of India,for the ?nancial support for this work through a major research project on “Aerogels”(No.SR/S2/CMP-01/2002).One of the authors,Sharad D.Bhagat,is highly grateful to DST,New Delhi for the fellowship under the same project.References
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使用Wincc Flexible与PLCSIM进行联机调试是可行的，但是前提条件是安装Wincc Flexible时必须选择集成在Step7中，下面就介绍一下如何进行两者的通讯。 Step1：在Step7中建立一个项目，并编写需要的程序，如下图所示： 为了演示的方便，我们建立了一个起停程序，如下图所示： Step2：回到Simatic Manager中，在项目树中我们建立一个Simatic HMI Station的对象，如果Wincc Flexible已经被安装且在安装时选择集成在Step7中的话，系统会调用Wincc Flexible程序，如下图所示：
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将画面连接变量，根据本文演示制作如下画面： 现在我们就完成了基本的步骤。
Step4：模拟演示，运行PLCSIM，并下载先前完成的程序。 建立M区以及Q区模拟，试运行，证实Step7程序没有出错。 接下来在Wincc Flexible中启动运行系统（如果不需要与PLCSIM联机调试，那么需要运行带仿真器的运行系统），此时就可以联机模拟了。 本例中的联机模拟程序运行如下图所示：
编订：__________________ 审核：__________________ 单位：__________________ 丁基橡胶装置简介和重点 部位及设备 Deploy The Objectives, Requirements And Methods To Make The Personnel In The Organization Operate According To The Established Standards And Reach The Expected Level. Word格式 / 完整 / 可编辑
文件编号：KG-AO-5622-57 丁基橡胶装置简介和重点部位及设 备 使用备注：本文档可用在日常工作场景，通过对目的、要求、方式、方法、进度等进行 具体的部署，从而使得组织内人员按照既定标准、规范的要求进行操作，使日常工作或 活动达到预期的水平。下载后就可自由编辑。 (一)装置发展及类型 1．装置发展 丁基橡胶在1940年6月问世，1943年投产，是美国的Exxon公司。在世界丁基橡胶生产行业中，Exxon、Bayer公司的丁基橡胶生产技术成熟可靠、水平较高，但从不转让技术，企图长期垄断丁基橡胶生产技术和市场。Exxon公司联合Bayer公司成立了子公司与北京燕化公司进行合作谈判，由于条件苛刻、技术费用很高，因而未有结果。 意大利的Pressindustria公司(以下简称n公司)从1971年开始对丁基橡胶理论开始研究1973年为Exxon公司提供搅拌器，1975年开始与前苏联合作进行新型丁基橡胶聚合反应器的研究，1976年取得成功。
丁腈橡胶/丁苯橡胶并用胶相容性研究 丁腈橡胶是一种强极性橡胶,丁苯橡胶是一种非极性橡胶,二者在热力学上是不相容,两相界面之间很难产生共交联,微观呈现相分离状态,相容性差,导致综合性能差。丁腈橡胶/丁苯橡胶并用胶的相容性直接取决于两相间是否有键合作用的存在,即共交联。 如果两相间产生共交联,那么相容性会得到提高,只有相容性提高了,两相间的相分离才能得到改善,宏观性能才能提高。本文首先采取了一种新的工艺,即两种橡胶分别加各自的配合剂制成母炼胶,停放一段时间,制备并用胶。 通过这种工艺,硫化剂一部分存在于各自的橡胶相中,可以防止在硫化时,由于胶料粘度的不同导致的硫化剂迁移问题,保证各组分都能得到有效交联;另一部分富集在二者相交的相界面上,从而可能在相界面上发生共交联等反应;通过拉伸试验对比发现新工艺比传统工艺的性能要好。通过对比例50/50进行傅里叶变换红外光谱分析(FT-IR)、交联密度测定、差示扫描量热分析(DSC)、扫描电子显微镜(SEM)的研究,结果表明:新工艺50/50产生了氢键,交联密度增大,产生了共交联,玻璃化转变温度相互靠近,断面粗糙程度增加,断裂纹的高度和宽度明显增加,且分散密集,说明断裂趋于韧性断裂,需要更多的断裂能量,即两相之间相互作用增强,界面间结合更加牢固,因此NBR/SBR并用胶相容性提高,性能提高。 其次在新工艺的基础上采取了硅烷偶联剂,利用其在高温下释放的活性硫,研究是否参与了界面间的共交联反应。通过无转子发泡硫化仪、DSC、扫描电子显微镜(SEM)对并用胶硫化特性、玻璃化转变温度、微观形貌之间关系的研究,结果表明:随着双-[γ-(三乙氧基硅)丙基]四硫化物(Si69)用量的增多,门尼粘度降低,硬度增加,拉伸强度增高,断裂伸长率下降;耐油性能变好,交联密度增大,
Processing of low-density silica gel by critical point drying or ambient pressure drying Valerie https://www.doczj.com/doc/c316538900.html,nd,Thomas M.Harris *,Dale C.Teeters Department of Chemistry and Biochemistry,University of Tulsa,600S.College Ave.,Tulsa,OK74104-3189,USA Received 5July 2000;received in revised form 20February 2001 Abstract Various methods for the production of low-density silica from silica gel were studied.The silica gel was prepared by the `two-step'sol±gel method.The `DSB process'(developed by Deshpande,Smith and Brinker),which takes the gel through solvent exchange,reaction with trimethylchlorosilane (TMCS)and ambient pressure drying (APD),was then applied.This processing provided a greater total pore volume,and more mesopores with diameters >50 A, than critical point drying (CPD),the conventional method for producing an aerogel.The high porosity was found to be due pri-marily to the solvent exchange step;in fact,the reaction with TMCS reduced the porosity.Reaction of the gel with trimethylmethoxysilane (TMMS)in the mother liquor (ethanol/water)provided higher pore volumes than the DSB process.This extra porosity may be attributed to poor wetting of the polar solvent in contact with the surface made hydrophobic through reaction with the TMMS;thus,the capillary forces that cause the gel to shrink are reduced.Finally,it was discovered that some loss of porosity occurs when CPD is conducted with carbon dioxide;speci?cally,the pressure pulse that occurs when the CPD cell is initially ˉooded with this liquid can damage the structure of the silica network.ó2001Elsevier Science B.V.All rights reserved. 1.Introduction Aerogel materials exhibit very high surface area and signi?cant nanoporosity.A number of appli-cations for these materials have been explored [1].The use of silica aerogels as high e ciency thermal insulation has received the greatest attention [2,3].The conventional method of producing an aerogel,discovered by Kistler [4]in 1931,involves removal of the solvent from a `wet gel'under supercritical conditions.This technique,referred to as critical point drying (CPD),avoids the build up of tensile stresses that cause the polymeric network to col-lapse as the vapor±liquid interface recedes into the gel. Since CPD requires the use of an autoclave,the technological utilization of aerogels has lagged far behind their development in the laboratory.However,a discovery by Deshpande,Smith and Brinker [5]involving silica aerogels may ?nally allow the full commercial potential of these ma-terials to be realized.In the `Deshpande,Smith and Brinker (DSB)process',the wet gel is washed with an aprotic solvent,reacted with trimethyl-chlorosilane (TMCS)and then dried at ambient pressure.This treatment minimizes shrinkage of the gel,through a reduction in the surface tension of the solvent and the contact angle between the solvent and the surface of the silica network [6]. Journal of Non-Crystalline Solids 283(2001)11±17 https://www.doczj.com/doc/c316538900.html,/locate/jnoncrysol * Corresponding author.Tel.:+1-9186313090;fax:+1-9186313404. E-mail address:thomas-harris@https://www.doczj.com/doc/c316538900.html, (T.M.Harris). 0022-3093/01/$-see front matter ó2001Elsevier Science B.V.All rights reserved.PII:S 0022-3093(01)00485-9
丁基橡胶装置简介和重点部位及设备 (一)装置发展及类型 1．装置发展 丁基橡胶在1940年6月问世，1943年投产，是美国的Exxon公司。在世界丁基橡胶生产行业中，Exxon、Bayer公司的丁基橡胶生产技术成熟可靠、水平较高，但从不转让技术，企图长期垄断丁基橡胶生产技术和市场。Exxon公司联合Bayer公司成立了子公司与北京燕化公司进行合作谈判，由于条件苛刻、技术费用很高，因而未有结果。 意大利的Pressindustria公司(以下简称n公司)从1971年开始对丁基橡胶理论开始研究1973年为Exxon公司提供搅拌器，1975年开始与前苏联合作进行新型丁基橡胶聚合反应器的研究，1976年取得成功。1983年PI公司对前苏联的下卡姆斯丁基橡胶厂的聚合反应器和聚合工艺进行改造，使其生产水平大大提高。1986年PI公司开始投入大量资金，完善了聚合反应器和聚合工艺技术，开发了聚合反应器数学模型，并通过引进专家掌握了丁基橡胶成套生产技术。 北京燕化公司同俄罗斯及PI公司进行了技术交流，并于1995年12月15日由中国石化总公司召开“关于引进意大利PI公司技术建设丁基橡胶生产装置论证会”，进而确定引进公司的技术建设在中国大陆建设一套3X104t／a的丁基橡胶装置。1997年10月14日，丁基橡胶装置在北京燕山石油化工股份有限公司合成橡胶事业部开始动工，于1999年12月28日正式投产。
2。装置类型 丁基橡胶装置是以高纯度异丁烯和异戊二烯为原料，用高纯度三氯化铝加微量水为催化剂，氯甲烷为稀释剂，采用淤浆法生产丁基橡胶的石油化工装置。是制造子午胎内胎和无内胎轮胎不可代替的材料，在包括电子、机械、医疗和食品等行业中有着非常广泛的用途。 (二)单元组成与工艺流程 1．单元组成 丁基橡胶装置主要由乙烯制冷单元、丙烯制冷单元、配料及催化剂配制单元、聚合和脯气单元、氯甲烷回收单元、氧化铝干燥再生单元、异丁烯和异戊二烯精制单元、中间罐区公用工程系统和后处理生产线等10个单元组成。 2．工艺流程概述 丁基橡胶是在极低的操作温度和半连续生产的条件下用异丁烯和异戊二烯聚合得到。催化剂为用氯甲烷作溶剂配制成的无水三氯化铝溶液，该催化剂溶液经过深冷进入到反应器。精制后的异丁烯和异戊二烯也用氯甲烷按一定比例配制成溶液，经过深冷后进人聚合反应器，在反应器中异丁烯和异戊二烯在催化剂存在下瞬时完成聚合反应，生成丁基橡胶胶粒。胶粒和未反应的单体和氯甲烷自聚合反应器顶部溢出进入到脱气釜用热水脱气，蒸出未反应的大部分单体和氯甲烷。在脱气釜中加入分散剂和抗氧剂，并加入烧碱溶液中和三氯化铝水解生成的盐酸。经脱气后的胶粒和水再经第一汽提釜和第二汽提釜进一步蒸出未反应的单体氯甲烷。
注射用溴化丁基橡胶塞包材相容性研究 李云峰 常山凯捷健生物药物研发（河北）有限公司 摘要：以河北橡一医药科技股份有限公司生产的注射用溴化丁基橡胶塞为研究对象，采用HPLC法对其中的可提取硫和抗氧剂BHT含量进行检测，并对以肝素钠注射液为提取液的胶塞进行研究。实验表明河北橡一医药科技股份有限公司生产的三个批号的胶塞通过适宜溶剂浸提，可获得可提取硫及抗氧剂BHT。在以肝素钠注射液为提取液的供试品中，无可提取硫及BHT浸出。 关键词：注射用溴化丁基橡胶塞；可提取硫；BHT；高效液相色谱法 0 引言 药品包装应适用于药品预期的临床用途[1]，相容性是其必须具备的特性之一。相容性研究是为考察药品包装材料与药品之间是否发生严重的相互作用，并导致药品有效性和稳定性发生改变，或者产生安全性风险而进行的一系列试验，包括包装材料对药品的影响，及药品对包装材料的影响[2，3]。 由于注射用溴化丁基橡胶塞直接与药液接触，注射用溴化丁基橡胶塞中在硫化过程中用到了硫，还使用了一些添加剂如抗氧剂BHT （2,6-二叔丁基对甲酚）来增强其性能，笔者通过提取试验对上述目标化合物进行了研究。 1实验部分 1.1材料与试剂 注射液用溴化丁基橡胶塞：河北橡一医药科技股份有限公司；批号：,,；肝素钠注射液（规格：5ml：5000单位)）：本公司自产，批号：140401；肝素钠注射液（规格：5ml：25000单位)）：本公司自产，批号：140402。 丙酮、2,6-二叔丁基对甲酚（BHT）、升华硫、三氯甲烷、无水乙醇。 甲醇、乙腈均为色谱纯。 1.2仪器 戴安U3000高效液相色谱仪；梅特勒FE20 型酸度计；梅特勒XS105型电子天平；西安安泰MCR-3型微波化学反应器。
WinCC Flexible 系统函数 报警 ClearAlarmBuffer 应用 删除HMI设备报警缓冲区中的报警。 说明 尚未确认的报警也被删除。 语法 ClearAlarmBuffer (Alarm class number) 在脚本中是否可用：有 (ClearAlarmBuffer) 参数 Alarm class number 确定要从报警缓冲区中删除的报警： 0 (hmiAll) = 所有报警/事件 1 (hmiAlarms) = 错误 2 (hmiEvents) = 警告 3 (hmiSystem) = 系统事件 4 (hmiS7Diagnosis) = S7 诊断事件 可组态的对象 对象事件 变量数值改变超出上限低于下限 功能键（全局）释放按下 功能键（局部）释放按下 画面已加载已清除 数据记录溢出报警记录溢出 检查跟踪记录可用内存很少可用内存极少 画面对象按下 释放 单击 切换（或者拨动开关）打开 断开 启用 取消激活 时序表到期 报警缓冲区溢出
ClearAlarmBufferProtoolLegacy 应用 该系统函数用来确保兼容性。 它具有与系统函数“ClearAlarmBuffer”相同的功能，但使用旧的ProTool编号方式。语法 ClearAlarmBufferProtoolLegacy (Alarm class number) 在脚本中是否可用：有 (ClearAlarmBufferProtoolLegacy) 参数 Alarm class number 将要删除其消息的报警类别号： -1 (hmiAllProtoolLegacy) = 所有报警/事件 0 (hmiAlarmsProtoolLegacy) = 错误 1 (hmiEventsProtoolLegacy) = 警告 2 (hmiSystemProtoolLegacy) = 系统事件 3 (hmiS7DiagnosisProtoolLegacy) = S7 诊断事件 可组态的对象 对象事件 变量数值改变超出上限低于下限 功能键（全局）释放按下 功能键（局部）释放按下 画面已加载已清除 变量记录溢出报警记录溢出 检查跟踪记录可用内存很少可用内存极少 画面对象按下 释放 单击 切换（或者拨动开关）打开 断开 启用 取消激活 时序表到期 报警缓冲区溢出 SetAlarmReportMode 应用 确定是否将报警自动报告到打印机上。 语法 SetAlarmReportMode (Mode) 在脚本中是否可用：有 (SetAlarmReportMode) 参数 Mode
邢台市龙滨橡塑制品有限公司 XINGTAI LONGBIN RUBBER AHD PLASTIC PRODUCTS CO.,LTD 出厂检验报告 产品名称防震胶型号规格 12600101000102 供应厂家芜湖美的检测项目23项 生产日期2015年7 月 22号合格项目22项 检测数量 5 检测日期2015年 7 月 22 号-2015年 8 月5号检测依据防震胶技术条件QMK-J54.037-2011 检测结论 按美的企标要求,本次试验共检项目23项，22项合格，1项不做判定。依据相关标准判定本次试验结果：合格 序号检验项 目 标准要求检验结果备注 1 标志标志内容与图样相符，印刷清楚标志内容与图样相符，印刷清楚合格 2 包装 质量 防振胶用纸箱包装纸箱包装合格 3 颜色黑色黑色合格 4 表面 质量 1.防振胶表面平整、光滑、无杂质、不含异物、 手摸无明显油渍 2.防振胶的结构由正面为保护塑料薄膜（PE）和 背面为离型纸组成 防震胶表面无杂质，较平整，正 面为塑料薄膜，背面为隔离纸 合格 5 结构 尺寸 尺寸规格应满足图纸要求，未注尺寸公差应符合 GB/T 3672-2002《模压、压出和压延实心橡胶制 品的尺寸公差》（厚度公差EC3与长、宽度公差 L3）级要求。详见下表。 详见下表。合格 6 初粘 性 室温下不小于20#球且实物粘贴无起翘、开 口、位移、流挂等不良现象。 实物黏贴良好，无翘边、流挂等 现象 合格 7 装配 性 a、将两块面积为100mm2的防振胶对粘，压缩 10％，然后沿接触处缓慢撕开（撕开时间≥5秒）， 中间能够拉出≥400mm的连接丝； b、将防振胶长边对包在有2个弯位的铜管 上（对包开口与铜管折弯方向相反，防振胶长边 要大于铜管弯位长度，见下图），压缩式样厚度 为原来的20%，在常温下（25℃）放置2h，2h 防震胶对沾拉丝460mm 防震胶对沾黏于铜管上，放置2 小时无反弹、松弛 合格
Colloids and Surfaces A:Physicochem.Eng.Aspects 277 (2006) 145–150 Silica-PMMA core-shell and hollow nanospheres Kai Zhang,Linli Zheng,Xuehai Zhang,Xin Chen,Bai Yang ? Key Lab of Supramolecular Structure and Materials,College of Chemistry 130012, Jilin University,2699#Qianjin Avenue,Changchun,PR China Received 8November 2005;received in revised form 15November 2005;accepted 17November 2005 Available online 18 January 2006 Abstract Monodispersed silica-polymer core-shell nanospheres (CSNs)were prepared by emulsion polymerization.To coat the cores by polymer,silica nanoparticles were modi?ed by 3-(trimethoxysilyl)propyl methacrylate (MPS).The thicknesses of polymer shells were found to be dependent on the amount of monomer and grafted silica nanoparticles,the concentration of emulsi?er and the sizes of grafted silica nanoparticles,and the morphologies of CSNs were affected by the kind of monomer.The formation mechanism of SiO 2-PMMA CSNs was speculated.In addition,we investigated the formation of hollow polymer nanospheres.? 2005 Elsevier B.V. All rights reserved. Keywords:Core-shell;Emulsion polymerization;Hollow;Nanospheres 1.Introduction During the past decades,there have been a lot of works devised with the preparation of core-shell nanospheres (CSNs)because of their excellent optical,electrical,thermal,mechan-ical,electro-optical,magnetic and catalytic properties [1–5].CSNs display interesting functions and characters,which come from different functional components in core and shell materials.Furthermore,CSNs provide a facile platform for the fabrication of hollow spheres or capsules by the removal of template cores.These CSNs and hollow capsules can open up potential applica-tions in catalysis,controlled delivery,arti?cial cells,light ?llers,low dielectric constant materials and photonic crystals [6–9].Various facile or clever procedures have been developed to prepare these CSNs and hollow spheres,including tem-plate directed self-assembly [10,11],template directed living polymerization [12,13],template directed aggregations [14–16],copolymerization of hydrophobic and hydrophilic monomer [17]and core-shell emulsion polymerization [18]. Using silica spheres as template cores to prepare silica-polymer CSNs is well known in the ?eld of the inorganic–organic CSNs.Silica-polymer CSNs are broadly used in research on the physical performances of composite materials,pho- ? Corresponding author.Tel.:+864315168478;fax:+864315193423.E-mail address:yangbai@https://www.doczj.com/doc/c316538900.html, (B.Yang). tonic crystals and antire?ection ?lm.Silica-polymer CSNs with various morphologies could be synthesized by physic-ochemical or chemical processes.After Bourgeat-Lami pre-pared silica-polystyrene (SiO 2-PS)core-shell microspheres by dispersion polymerization [19],other polymerization proce-dures involving emulsion,miniemulsion,and atom transfer radical polymerization have been tried to realize the coat-ing of silica spheres with polymer shells [20–24].Recently,Asher et al.have successfully synthesized monodispersed SiO 2-polymer core-shell spheres in submicrometer via the dis-persion polymerization,and then used them as the building blocks for the fabrication of photonic crystals [25].How-ever,the preparation of monodispersed SiO 2-polymer core-shell spheres in nanoscale is still an attractive work because of their potential applications in photonic crystals and antire?ection ?lm. In this paper,we report the preparation of 131–225nm silica-polymethyl methacrylate (SiO 2-PMMA)CSNs with 51–195nm cores by an emulsion polymerization.We have investigated the effects of several reaction parameters on the morphologies and sizes of SiO 2-polymer CSNs,such as,different monomers (MMA and St),concentration of emulsi?er,amounts of grafted silica and monomer.And then,the formation mechanism of SiO 2-polymer CSNs was speculated and a suitable system for preparing silica-polymer CSNs was con?rmed.Finally,hollow polymer nanospheres were obtained via an etching process using a solvent. 0927-7757/$–see front matter ? 2005 Elsevier B.V. All rights reserved.doi:10.1016/j.colsurfa.2005.11.049
顺丁橡胶装置简介和重点部位及设备 一、装置简介 (一)装置发展及类型 1。装置发展 1959年日本的Bndgestone公司开始研制镍系BR顺丁橡胶，并于1964年年底建成2．5x104t／a的生产装置。顺丁橡胶在中国的研究1959年也已开始，经过大量的实验，完成了小试、中试及工业，眭实验。又通过全国性的攻关会战，进而取得了万吨级工业装置的数据。聚合技术开发始于1959年，中国科学院长春应用化合研究所开始了催化剂的开发工作。1965年在锦州和兰州开始了中试，1966年建成生产能力为1000t／a的实验装置。1969年确立了以抽余油为溶剂的生产工艺。1971年在北京燕山石油化工公司合成橡胶厂建成了我国第一套1．5X104t ／a的生／c装置，并生产出了合格的顺丁橡胶。此后，又在锦州石化公司、上海高桥化工厂、齐鲁石化公司橡胶厂、巴陵石化公司合成橡胶厂等相继建成了4套工业生产装置。 我国的顺丁橡胶技术经过多年的不断改进和多次技术攻关，工艺逐渐完善，产品质量稳步提高，已经向欧、美及东南亚等国家出口。同时顺丁橡胶成套技术已经成功实现了对意大：利和我国台湾省的技术转让。 2000年，我国生产顺丁橡胶的厂家已发展到8个，现有生产能力已经达到31．34X104；t／a，。 2．装置类型
顺丁橡胶的关键技术是聚合技术。生产顺丁橡胶的催化剂体系有锂、钛、钴、镍、钕等。不同的催化剂得到的不同橡胶结构的橡胶，用锂系催化剂得到的橡胶 顺式1，4—结构含量为35％—40％，称为低／顷式聚丁二烯橡胶，用钛系催化剂得到的橡胶，顺式含量为90％，由钴、镍、钕系制得的橡胶，顺式含量为96％—98％，统称为高顺式聚丁二烯橡胶，即顺丁橡胶。我国生产顺丁橡胶聚合所采用的催化 剂为镍系。 丁二烯抽提所用的萃取剂目前国内一般采用N，N—二甲基甲酰胺(DMF)和乙腈。本节主要以DMF法抽提丁二烯为主进行介绍。 (二)单元组成与工艺流程 1．单元组成 顺丁橡胶生产装置主要由丁二烯抽提、聚合及凝聚、干燥、成型包装等三大 单元组成。丁二烯抽提单元是／顷丁橡胶装置的龙头，绝大部分丁二烯含量43％左右的混合碳四馏分在这里经过萃取和精馏，从而直接从碳四馏分中提取高纯度 的丁二烯单体供聚合单元使用。 丁二烯聚合单元是顺丁橡胶装置的核心反应部分，是顺丁橡胶生产的心脏， 其任务是将丁二烯、催化剂、溶剂油在规定的工艺条件下进行配位阴离子聚合， 经聚合釜的连续聚合，得到顺式含量大于96％的1．4聚丁二烯胶液，然后加入 防老剂，经静态混合器送往胶液罐，供凝聚单元使用。 凝聚单元主要是应用水蒸气蒸馏原理，借助于热水、蒸汽以及机械搅拌等作用，完成对丁二烯胶液中的溶剂及未反应的丁二烯除去并回收，将悬浮在凝聚釜 中的颗粒状经脱水、干
KXT型橡胶减震器（简介） 名称：橡胶减震器 型号：KXT型 橡胶软接头又称作减振器、管道减震器、避震喉、软接头等。本产品引进国外先进生产工艺，制作过程中内层受到高压力，锦纶帘子布和胶层得到更好的结合，比普通型可曲挠橡胶接头的工作压力更高，质量更好。它的特点是内胶层混然一体，光洁无缝痕，标签采用硫化工艺，与产品结合在一起。 详细介绍 橡胶软接头，该产品是金属管道的柔性联接器，由内胶层、锦纶帘子布增强、外胶层复合的橡胶球体和松套金属法兰组成。具有耐压高、弹性好、位移量大、平衡管道偏差、吸收振动、降低噪音效果好、安装方便等特点，可广泛用于供水排水、循环水、暖通空调、消防、造纸、制药、石油化工、船舶、水泵、压缩机、风机等管道系统。普通型用于输送-15℃～115℃的空气、压缩空气、水、海水、油、酸、碱等。特殊型用于输送-30℃～250℃以上的上述介质或油、浓酸浓碱、固态物料。 技术参数 项目 型号 KXT-1 KXT--2 KXT--3 工作压力MPa(kgf/cm2 ) 1.0(10） 1.6（16） 2.5（25） 爆破压力MPa(kgf/cm2 ) 2.0（20） 3.0（30）
4.5（45） 真空度KPa(mm/Hg) 53.3（400） 86.7（650） 100（750） 适用温度℃：-15℃～115℃特殊可达-30℃～250℃ 适用介质：空气、压缩空气、水、海水、热水、油、酸、碱等。
注：1、特殊要求可来函来图定制，法兰按《全国通用给排水标准图集》，其它按HG/T2289-92。 2、DN350-600(2)型工作压力为1.6MPa，DN32-400(3)型工作压力为2.5MPa。 3、DN700-DN1200工作压力为1.0MPa，DN1400工作压力为0.6MPa,DN1600-DN1800工作压力为0.4MPa，法兰按0.6MPa 选取。DN2000工作压力为0.25MPa,法兰按0.6MPa压力选取。 4、悬空给水使用DN200以上产品，管道必须有固定支撑或固定托架，否则产品应安装防拉脱装置。 5、用户使用橡接头，对应法兰应是阀门法兰或符合GB/T9115.1(RF)法兰。
电话：0086-25-86371192、86371191 传真：0086-25-86371193 SiLink TM 硅烷偶联剂 KH-450 产品概述： SiLink TM 硅烷偶联剂KH-450是一种专门用于水性体系的硅烷偶联剂，用以提高丙烯酸乳液、丁苯乳液、聚氨酯水性分散体等水性涂料、胶粘剂对于玻璃、金属的附着力和耐水性。 产品优点： 1、贮存期长，达1年以上，与水性树脂相容性好、不冲突，彻底解决了普通硅烷偶联剂在水性体系下易自聚、贮存期短的缺点。 2、不黄变，不影响产品外观。 3、优越的湿态和干态附着力，对于涂层的耐水性帮助巨大。 4、提高拉伸强度，同时不影响伸长率。 5、提高撕裂强度和耐持久性 6、耐老化性能优越，老化前后性能表现基本一致。 物化性质： 指标 典型值 外观 无色至淡黄色透明液体 密度(ρ20), g/cm 30.98 闪点, ℃ 121 粘度（25 ℃）,cSt 3 用途： 在 pH 值6~8.5 条件下，SiLink TM 硅烷偶联剂KH-450在含羧基的乳液（丙烯酸，丁苯、聚氨酯等）中表现最好。 SiLink TM 硅烷偶联剂KH-450作为粘接促进剂或交联剂，可用于以下水性单组份体系：汽车用层压胶粘剂、家具用层压胶粘剂和植绒胶粘剂等。在这些应用中，使用SiLink TM 硅烷偶联剂KH-450可达到以单组份体系取代双组份水性胶粘剂之目的。硅烷改性的水性单组份体系的 好处在于提高附着力、改善工艺稳定性并减少毒性。 SiLink TM 硅烷偶联剂KH-450的主要优点是在水性体系下长期稳定，且不黄变。传统硅烷如KH-560在水性丙烯酸密封胶中的用量不能超过0.3 phr ，且储存期不超过1周；但对于SiLink TM 硅烷偶联剂KH-450来说，1phr 的用量不会影响储存期，水性丙烯酸密封胶的储存期可长达1年以上。
WinCC Flexible 系统函数报警 ClearAlarmBuffer 应用 删除HMI设备报警缓冲区中的报警。 说明 尚未确认的报警也被删除。 语法 ClearAlarmBuffer (Alarm class number) 在脚本中是否可用：有 (ClearAlarmBuffer) 参数 Alarm class number 确定要从报警缓冲区中删除的报警： 0 (hmiAll) = 所有报警/事件 1 (hmiAlarms) = 错误 2 (hmiEvents) = 警告 3 (hmiSystem) = 系统事件 4 (hmiS7Diagnosis) = S7 诊断事件 可组态的对象 对象事件 变量数值改变超出上限低于下限 功能键（全局）释放按下 功能键（局部）释放按下 画面已加载已清除 数据记录溢出报警记录溢出 检查跟踪记录可用内存很少可用内存极少 画面对象按下 释放 单击 切换（或者拨动开关）打开 断开 启用 取消激活 时序表到期 报警缓冲区溢出 ClearAlarmBufferProtoolLegacy 应用
该系统函数用来确保兼容性。 它具有与系统函数“ClearAlarmBuffer”相同的功能，但使用旧的ProTool编号方式。语法 ClearAlarmBufferProtoolLegacy (Alarm class number) 在脚本中是否可用：有 (ClearAlarmBufferProtoolLegacy) 参数 Alarm class number 将要删除其消息的报警类别号： -1 (hmiAllProtoolLegacy) = 所有报警/事件 0 (hmiAlarmsProtoolLegacy) = 错误 1 (hmiEventsProtoolLegacy) = 警告 2 (hmiSystemProtoolLegacy) = 系统事件 3 (hmiS7DiagnosisProtoolLegacy) = S7 诊断事件 可组态的对象 对象事件 变量数值改变超出上限低于下限 功能键（全局）释放按下 功能键（局部）释放按下 画面已加载已清除 变量记录溢出报警记录溢出 检查跟踪记录可用内存很少可用内存极少 画面对象按下 释放 单击 切换（或者拨动开关）打开 断开 启用 取消激活 时序表到期 报警缓冲区溢出 SetAlarmReportMode 应用 确定是否将报警自动报告到打印机上。 语法 SetAlarmReportMode (Mode) 在脚本中是否可用：有 (SetAlarmReportMode) 参数 Mode 确定报警是否自动报告到打印机上： 0 (hmiDisnablePrinting) = 报表关闭：报警不自动打印。
YF-ED-J7120 可按资料类型定义编号 顺丁橡胶装置危险因素及防范措施实用版 In Order To Ensure The Effective And Safe Operation Of The Department Work Or Production, Relevant Personnel Shall Follow The Procedures In Handling Business Or Operating Equipment. （示范文稿） 二零XX年XX月XX日
顺丁橡胶装置危险因素及防范措 施实用版 提示：该解决方案文档适合使用于从目的、要求、方式、方法、进度等都部署具体、周密，并有很强可操作性的计划，在进行中紧扣进度，实现最大程度完成与接近最初目标。下载后可以对文件进行定制修改，请根据实际需要调整使用。 (一)火灾爆炸危险 火灾爆炸和丁二烯自聚是本装置的主要危 险，丁二烯属于易于自聚的物质，丁二烯生成 端基过氧化自聚物的倾向十分明显。丁二烯端 基聚合物坚硬且不溶于已知溶剂，即便加热也 不能熔融。由于丁二烯生成的端基聚合物在丁 二烯中的溶解度很小，所以很容易沉积在浓缩 层中，黏附在器壁和管道上，造成管道、阀门 和设备堵塞或涨裂。在60—80℃或光照、撞 击、摩擦时能发生爆炸。生产过程对于氧含
量、水含量等要求非常严格，丁二烯在少量的氧存在的情况下就可能被氧化生成过氧化物，引发自聚。过氧化自聚物在空气中的允许浓度仅为100mg／m3，并在125℃以上就可以发生分解爆炸。 此外，乙烯基乙炔是一种极易分解爆炸的物质，当乙烯基乙炔浓度高于50％、分压大于0．075MPa时就有引起爆炸的危险。所以在操作时要严格检查和控制DA—103塔釜温度、溶剂量和回流量，发现异常及时进行处理。 总体而言加强防火防爆、防静电、防泄漏、防丁二烯自聚、防雷等安全措施，应成为本装置关注的重点问题。 (二)毒性危害 丁二烯对人体的危害。慢性中毒对神经系