A Boron-based Adhesion Aid for Efficient Bonding of Silicone Rubber and Epoxy Resin

We improved the adhesion between silicon based insulating materials and epoxy resin composites by adding the adhesion promoter cycloborosiloxane(BSi,cyclo-1,3,3,5,7,7-hexaphenyl-1,5-diboro-3,7-disiloxane).The experimental results show that the addition of BSi in the silicone rubber(SR)system significantly increases the tensile shear strength between BSi and epoxy resin(EP),reaching 309%of the original value.On this basis,the mechanism of BSi to enhance the adhesion effect was discussed.The electron deficient B in BSi attracted the electron rich N and O in EP to enhance the chemical interaction,combined with the interfacial migration behavior in the curing process,to improve the adhesion strength.This study provides the design and synthesis ideas of adhesive aids,and a reference for further exploring the interface mechanism of epoxy resin matrix composites.

Synthesis and Properties of Perfluorinated Alkyl Silicone Oil Modified Epoxy Resin

Perfluorinated alkyl silicone oil （PFASO） was successfully synthesized from N-ethyl-N- hydroxylethyl perfluorinated octane sulfonamide, succinie anhydride and amino silicone oil by esterification and amide reaction at moderate temperature in the presence of different catalysts. The chemical structure of the synthesized samples was characterized by Fourier transform infrared spectroscopy （FT-IR）, the relative molecular mass（MM） and molecular mass distribution（MMD） of PFASO were tested by gel filtration chromatography（GFC）. A commercial epoxy resin （DGEBA） was modified with PFASO, with the content of PFASO 1-5 phr. Thermo-gravimetric analysis （TGA）, impact tests, scanning electron microscope （SEM） and water contact angle test were applied to provide accurate results on the thermal stability, toughness and hydrophobicity of PFASO/epoxy complex. The experimental results reveal that epoxy resins can be successfully modified by adding a small amount of as-synthesized modifiers via simple direct mixing, and verify that the as-synthesized modifier can improve the toughness and hydrophobicity of epoxy resin without sacrificing its thermal properties.

Development of Siliconized Epoxy Resins and Their Application as Anticorrosive Coatings

The present work involves the development of siliconized epoxy resin to overcome the drawback of epoxy resin like poor impact strength, high rigidity and moisture absorbing nature because of which they are not applied as corrosion resistant coating. By embedding silicone into the back bone of polymeric resin the above drawback can be reduced to substantial level. For achieving this, siliconised epoxy resins were prepared by reacting amine terminated silicone resin with novolac epoxy resin and meta-phenylenediamine was used as curing agent. The applied films of coating were baked at 150oC. Cured films were evaluated for their thermal, mechanical, chemical and corrosion resistance properties to ascertain the commercial utility of these eco-friendly resin for use in anti corrosive formulations. The siliconized epoxy resins system was found to exhibit good thermal and anticorrosive properties.

Preparation of Silica Powder in Epoxy Resin Wear-Resistant Coating

Silicon powders possess good thermal stability and rub resistance and can be used as the filler of high temperature wear-resistant coating;it can possess good wettability and dispersibility in the organic polymer by surface modification of silane coupling agent. Organic silicon has good thermal stability, which can modify the frangibility and thermal stability of epoxy resin. A certain proportion of modified silica powder, curing agent and additives were dispersed to modified epoxy resin can compound wear-resistant coating. The results show that: the modification effect can be the best if the dosage of silane coupling agent is 1.5% of silicon powder. If the methyl triethoxy silane is 50 phr and modified silica powder is 200 phr, then various performances of coating tend to be the best.

Influence of aliphatic epoxy monomer on the blowing-out effect in the flame retardant epoxy resins

An aliphatic epoxy monomer＂polypropyleneglycol-diglycidylether（PPGDGE,YF878）＂is loaded in the epoxy resins（EP）to evaluate the influence of epoxy structure on the blowing-out effect,which is caused by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide（DOPO）and octaphenyl silsesquioxane（OPS）.The flame retarding properties of these EP composites were tested using the LOI and UL-94 procedures.The pyrolytic gases produced and the thermal stability of the EP composites with different flame retardants were detected by TGA-FTIR in air.The negative effect of YF878 was detected from the TTI,HRR,and p-HRR results after the cone calorimeter test.The char produced by the EP composites after the cone calorimeter test was investigated by FTIR.It is proposed that the aliphatic chain of the YF878 is easy to break down and produce combustible gases,so it does not easily form a crosslinked structure in the condensed phase.These results are very helpful for investigation of the conditions under which the blowing-out effect in epoxy resins can be caused by synergy of phosphorous and silicon.

Synthesis and Crystal Structure of a Two-hydroxyphenyl Adamantane-type Epoxy Resin

A two-hydroxyphenyl adamantane-type epoxy resin oligomer,namely 1,3-bis（4-（2,3-epoxpropyloxy）phenyl） adamantine （BEPAD）,has been synthesized and structurally characterized by single-crystal X-ray diffraction.The unit cell of C28H32O4：Mr =432.5,monoclinic,space group P21/n,with a =10.510（6）,b =16.972（9）,c =13.374（7） （A）,β =109.356（6）°,V=2251（2） （A）3,Z =4,Dc =1.277 Mg·m^-3 and μ（MoKa） =0.084 mm^-1.In BEPAD,the methylene and epoxide rings on two ends are statistically disordered.The intermolecular interactions are also discussed,suggesting that the intermolecular interactions in BEPAD are stronger than that in the crystals of similar compounds due to the large adamantine group between the two benzene rings.

湿热环境下脂环族环氧树脂绝缘子和硅橡胶复合绝缘子芯棒-护套界面老化特性研究

脂环族环氧树脂绝缘子因其优异的电气性能和良好的芯棒-护套界面粘接能力,有效地解决了早期硅橡胶体系复合绝缘子的界面问题,有望广泛应用于输电线路上。目前缺少对环氧树脂复合绝缘子和硅橡胶复合绝缘子芯棒-护套界面吸水老化特性的对比研究。该文对比了脂环族环氧树脂材料和硅橡胶材料的吸水、脱水、透水和透湿特性,并进行了水扩散试验方法,结果表明脂环族环氧树脂绝缘子具有更好的芯棒-护套界面粘接和耐老化性能。该文同时研究了氢氧化铝(alumina trihydrate,ATH)填料对环氧树脂吸水渗水特性的影响,为绝缘子用脂环族环氧树脂配方中ATH粒径和添加量的确定提供了理论支持。

微米BN-纳米SiO_(2)联合改性环氧树脂复合材料的制备与介电性能研究

环氧树脂因其加工工艺性好、粘结性高、介电性能优良,在高压输电、电机绝缘、电力电子封装等领域有广泛的应用。本文选用具有较高的热导率和良好的介电性能的六方氮化硼(h-BN),以及具有较好的导热性能二氧化硅(SiO_(2))作为掺杂填料改性双酚A型环氧树脂。研究了掺杂填量和比例对复合材料介电常数实部和虚部频谱的影响,实验结果分析表明掺杂总填量为10 wt%-20 wt%,BN与SiO_(2)的质量比为80:20至70:30时,复合环氧树脂样品在介电常数实部和虚部均有一定的改善,与纯环氧树脂相比,复合环氧树脂样品的介电性能得到了提升。

互穿网络结构的二氧化硅/环氧树脂复合材料的制备及介电性能研究

环氧树脂(EP)具有较高的电绝缘性能和较低的介电损耗,因此被广泛应用于电气设备和电子封装等绝缘材料领域。由于传统EP耐热性能较差、韧性不足,极大限制了其作为微电子元器件在高频电场下的使用。本工作以硅烷偶联剂(3-环氧乙基甲氧基丙基)三甲氧基硅烷(KH-560)和正硅酸乙酯(TEOS)为原料,通过溶胶-凝胶法合成末端含有环氧基团的新型端环氧基纳米SiO_(2)(E-SiO_(2)),用其对E-51型EP进行改性,在固化剂作用下使E-SiO_(2)和EP上的环氧基团发生开环反应,通过有机EP与无机E-SiO_(2)填料之间的化学键结合,制备出具有互穿网络结构的E-SiO_(2)/EP复合材料。本工作研究了添加E-SiO_(2)对EP固化反应工艺和综合性能的影响,以期在保证EP低介电常数和低介电损耗的同时,赋予其良好的韧性和耐热性能,为EP在高频电路下的应用奠定基础。

水性有机硅改性环氧树脂的制备与性能

利用二甲基二氯硅烷(DMDCS)与环氧树脂E51中-OH缩合反应合成有机硅改性环氧树脂,并采用相反转法制备水性有机硅改性环氧树脂,以疏水性优选有机硅改性环氧树脂合成条件,分析了乳化工艺对乳液平均粒径的影响,并考察了固化膜性能。结果表明,在环氧树脂40 g、DMDCS 1.6 g、溶剂用量20 mL、50℃反应8 h的条件下,有机硅改性环氧树脂与水的接触角为106.8°;当乳化剂用量为25%、乳化温度为65℃、剪切机转速为3000 r/min时,乳液平均粒径为1.011μm,储存稳定性(30 d)和离心稳定性(3000 r/min,30 min)良好;水性有机硅改性环氧固化膜固化时间短,具有优良的疏水性、力学性能、耐腐蚀性能。

有机硅改性环氧树脂的合成及其清漆涂层的防腐性能研究

将自制的反应性甲基苯基硅树脂(RMPSR)和双酚A型环氧树脂(E-51)在二甲苯中混合均匀,并在高温下使RMPSR分子上的活性甲氧基与E-51树脂主链上的羟基发生缩合反应,制得甲基苯基硅树脂改性环氧树脂。在改性树脂中加入脂环族胺类固化剂4,4′-二氨基二环己基甲烷,将其涂布在马口铁上热固化,制得透明的清漆涂层。采用红外光谱和核磁共振氢谱对改性树脂的化学结构进行表征,使用电化学工作站和盐雾箱研究涂层的防腐性能。结果表明,有机硅树脂的引入明显提升了涂层的防腐性能,其中ER-20在50 g/L的NaOH溶液中浸泡240 h后涂层表面仅有微小气泡产生,相较于E-51,其耐醇性能无明显下降,且阻抗模值、容抗弧以及极化电阻明显增大。改性树脂涂层的耐盐雾和耐盐溶液性能也有显著提升,即使在腐蚀介质中浸泡480 h后,其阻抗模值仍能达到2.63×10^(7)Ω·cm^(2)(而此阶段E-51阻抗模值仅为10^(3)数量级),表现出良好的电化学防腐蚀性能。

水性丙烯酸涂层改性研究进展

简单阐述了水性丙烯酸树脂的单体结构、聚合方法以及应用现状;较为系统地总结了根据不同材料改性水性丙烯酸树脂的研究进展,改性材料可归纳为纳米材料、有机硅、有机氟、聚氨酯和环氧树脂以及一些新型材料等。重点论述了改性材料对水性丙烯酸树脂进行改性的反应机理、相应的微观结构及性能提高情况。展望了水性丙烯酸涂料发展的方向。

溶胶-凝胶法制备环氧树脂/纳米SiO_2复合材料中纳米粒子的分散性研究

用溶胶-凝胶法制备环氧树脂/纳米SiO2复合材料,研究了在脱除溶剂以及反应副产物过程中温度、表面改性剂对纳米SiO2粒子的分散性、固化后样品力学性能的影响。研究表明:纳米SiO2的引入对环氧树脂的力学性能有一定的提高;随着体系溶剂脱除温度的升高纳米粒子的团聚明显;加入表面改性剂能够阻止纳米粒子的团聚,硅烷偶联剂KH550比表面活性PEG剂能够更好地阻止纳米粒子的团聚;但是表面活性剂PEG的加入会使纳米复合材料的力学性能有一定程度的下降。

氨基-环氧基新型有机硅固化体系

以六甲基二硅氧烷、四甲氧基硅烷为原料合成了MQ树脂,然后与带环氧基的硅氧烷反应,合成了环氧基改性硅树脂;用γ-氨丙基三乙氧基硅烷合成氨基笼形倍半硅氧烷(氨基POSS)。并用红外光谱仪和X射线衍射仪表征了二者。将氨基POSS作为环氧基改性硅树脂的固化剂,利用多氨基和环氧基的开环加成反应组成一种新型有机硅固化体系。考察了环氧基改性硅树脂与氨基POSS的质量比对固化体系表干时间及固化物硬度的影响、固化物的耐热性。结果表明,环氧基改性硅树脂与氨基POSS的质量比为100∶1～150∶1时,表干时间较快,固化物表面光滑平整、硬度较好;环氧基改性硅树脂与氨基POSS的最佳质量比为100∶1;此固化体系室温下的操作时间较长,放置4周后黏度上升不超过15%;差热分析结果显示,固化物在40～300℃时的质量损失率为5%左右,分解温度在450℃左右,在681.28℃时的残留率仍有53%。

高强度环氧-酰亚胺粘合剂的研制

选用双马来酰亚胺(BMI)对环氧树脂进行改性,制得一种高强度环氧-酰亚胺体系的ET粘合剂,并对ET粘合剂进行了一系列性能研究。结果表明:ET粘合剂的拉伸剪切强度最高达28.4 MPa,吸水率小于1%,并具有良好的电学性能和工艺性能。

4-氟苯基异氰酸酯及纳米SiO_2改性环氧有机硅树脂涂层的制备及性能研究

用4-氟苯基异氰酸酯改性环氧有机硅树脂(ES),使树脂接枝含氟基团,增强了树脂的疏水性,使腐蚀性物质不易粘附。改性树脂中再添加氢氧化铝包覆的纳米SiO2,以提高涂层的致密性,使腐蚀性介质难以侵入。通过双重改性的环氧有机硅涂层具有极低的表面能和优良的防腐蚀性。

LED封装用有机硅-环氧树脂的合成与性能研究

有机硅-环氧树脂兼具有机硅和环氧树脂的优点,广泛用于环氧树脂改性剂、有机硅增粘剂和LED封装基体树脂。以端氢基苯基硅油(HTPS)与3,4-环氧环己基甲基甲基丙烯酸酯(ECMA)为原料,采用硅氢加成法合成了有机硅-环氧树脂(PSER)。探索了PSER的合成反应条件,用红外光谱表征了其结构,并将PSER固化后应用于5050和2835贴片灯珠。结果表明,向ECMA和铂金催化剂混合物中滴加HTPS,在反应温度50℃、反应时间5 h、ECMA中C=C与HTPS中Si—H键的摩尔比为1∶1时,得到的PSER树脂无色透明,储存稳定,折射率达1.535;经过3次回流焊,死灯率为0%,适合作为LED封装基体树脂。

TG-siloxane改性BPFER/mXDA体系固化反应动力学与热性能

以1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(DSX)和环氧氯丙烷(ECH)为原料,利用相转移催化剂,合成双酚F环氧树脂(BPFER)改性剂N,N,N′,N′-四缩水甘油基-1,3-二氨丙基-1,1,3,3-四甲基二硅氧烷(TG-siloxane),并用FTIR、13 C NMR谱图对其结构进行了表征。对TG-siloxane改性BPFER/mXDA(间苯二甲胺)体系的固化动力学进行了研究。根据DSC曲线和Starink方程,得该体系表观固化活化能为51.52kJ.mol-1。用esták-Berggren模型求得不同升温速率下的表观因子、反应级数。动力学方程表明,升温速率对固化反应影响明显;所得方程用于预估反应进程时,与实测值吻合程度高。TG分析表明,TG-siloxane改性BPFER/mXDA体系固化物的耐热性能优于单纯BPFER/mXDA固化物。

真空-紫外辐照对SiO_2/MoS_2/酚醛环氧树脂涂层摩擦学性能的影响

为了研究真空-紫外辐照对润滑涂层的影响,采用地面模拟装置对添加SiO2前后的MoS2/酚醛环氧树脂涂层进行辐照,考察了辐照前后涂层的摩擦学性能。结果表明,真空-紫外辐照使涂层的摩擦系数、耐磨性分别呈降低、增强趋势。此外,SiO2的添加在一定程度上提高了复合涂层的摩擦学性能和抗紫外辐照性能。

自修复环氧树脂中间体-含有机硅氧烷双马来酰亚胺的合成与表征研究

含有机硅氧烷双马来酰亚胺是自修复环氧树脂的关键中间体材料。通过含活性端基的单马来酰亚胺与两端含活性基团的有机硅化合物反应生成有机硅氧烷双马来酰亚胺,克服了含硅二元胺合成需要贵金属催化剂且产率低的缺点,使有机硅氧烷双马来酰亚胺的产率达到90%以上,产率受合成溶剂、合成环境中水分、反应副产物HCl的去除程度影响。采用IR和NMR对有机硅氧烷双马来酰亚胺及其合成中各级产物的结构进行了分析与表征。