室温固化加成型有机硅灌封胶粘接性能研究

通过含环氧基、丙烯酰氧基和乙烯基的低聚硅氧烷增粘剂(HBV)与钛酸异丙酯的复配使用制得一款室温固化加成型有机硅灌封胶,当增粘剂HVS和钛酸异丙酯的添加量分别为2质量份(phr)和0.5 phr时,灌封胶在室温(25℃)固化后与铝材、PCB的粘接剪切强度分别达到0.92MPa和0.88 MPa,同时还具备良好的力学性能、储存稳定性和粘接稳定性。     

BN/环氧树脂导热灌封胶的制备与性能

采用硅烷偶联剂KH-560对氮化硼(BN)进行表面处理,用于制备BN/环氧树脂导热灌封胶。结果表明,随着BN用量的增加,环氧导热灌封胶的剪切强度下降,导热性能则增加,表面改性有助于提高环氧灌封胶的剪切强度和导热性能。CTBN的加入可有效提高剪切强度。当改性BN和CTBN质量分数均为15%时,BN/环氧灌封胶具有较理想的剪切强度、热性能和导热性能。     

风电电机槽口用环氧灌封胶的热性能研究

为探究风电电机用环氧灌封胶的耐候性,本研究对两种自制的风电电机槽口用环氧灌封胶进行了热性能研究.研究结果表明:两种环氧灌封胶起始分解温度分别为271和278℃,高于风电电机通常的运行温度155℃;热变形温度较低,分别是-20和24.3℃;在高低温及浸水环境中,拉伸剪切强度比工业上用的有机硅灌封胶提高了近3 MPa,与基...     

加成型有机硅灌封胶的粘接性研究

采用六乙烯基二硅氧烷为封头剂的聚二甲基硅氧烷为基础聚合物,环氧基团封端的聚二甲基氢基硅氧烷为交联剂,加入硅烷偶联剂、抑制剂、催化剂和无机填料制备加成型灌封胶,并对其硫化后的粘接性进行了研究。结果表明以100份六乙烯基聚二甲基硅氧烷、20份1,3-二缩水甘油醚氧基丙基-聚二甲基氢基硅氧烷、0.8份异氰酸丙基三甲氧基硅烷、100份氧化铝、100份石英粉、0.1份乙炔基环己醇和0.6份铂催化剂制得的有机硅加成型灌封胶在100℃烘烤2 h后,对铝片的剪切强度达到1.08 MPa;在室温25℃和相对湿度50%的环境下硫化7 d,对铝片的剪切强度达到0.75 MPa。     

管道防腐用环氧化SBS热熔胶的研制

利用有机过氧化物对SBS(苯乙烯-丁二烯-苯乙烯三嵌段共聚物)进行环氧化改性,得到ESBS(环氧化SBS);然后以此为基体树脂,辅以适宜种类及用量的增黏树脂、增塑剂和抗氧化剂等,制备出一种油气管道防腐用ESBS基热熔胶。结果表明:制备ESBS基热熔胶的最佳配方(以质量分数计)为47%ESBS、47%增黏树脂、1%抗氧剂和5%增塑剂;经环氧化改性后,ESBS基热熔胶对极性材料的粘接强度明显提高,其剥离强度和(钢/钢)剪切强度均满足使用要求。     

耐高温环氧有机硅灌封胶的研制

将带有活性基团的有机硅预聚体与环氧树脂(EP)在一定条件下反应4 h后,合成了环氧有机硅树脂;然后加入自制的活性硅微粉、适宜的固化剂和固化促进剂,制得环氧有机硅灌封胶。研究结果表明:采用单因素试验法优选出制备该灌封胶的最佳配方是w(改性复合酸酐)=75%、w(促进剂)=1%和w(自制活性硅微粉)=40%(均相对于环氧有机硅树脂质量而言),此时灌封胶的耐热性能和粘接性能俱佳,其起始固化温度由150℃左右降至120℃左右,常温剪切强度超过17 MPa,300℃剪切强度超过2 MPa。     

固化剂对酚醛树脂灌封胶性能的影响

为满足灌封胶黏剂中温固化耐高温的要求,研制新型耐高温灌封胶黏剂体系是十分重要的。研究了酚醛树脂固化剂对酚醛树脂挥发份、粘接强度、玻璃化转温度、固化温度等的影响,确定了固化剂和酚醛树脂最佳固化比例。表明采用的酚醛树脂固化剂可以显著降低酚醛树脂的挥发份,降低酚醛树脂固化温度,提高常温粘接强度,缺点是使酚醛树脂的玻璃化转变温度和高温剪切强度稍有下降,显示了固化剂的优异性能。该胶黏剂作为中温固化耐高温灌封胶黏剂可以满足航空工业耐高温的技术要求。     

丙烯酸酯液体橡胶改性环氧树脂胶粘剂的研究

以侧链含环氧基团的丙烯酸酯液体橡胶为改性剂 ,二乙撑三胺基甘油正丁基醚为固化剂制备了一种室温固化环氧树脂胶粘剂。重点研究了其粘接工艺性、力学性能和丙烯酸酯液体橡胶的改性作用。研究结果表明 :该胶粘剂具有较好的粘接工艺性能和拉剪强度 ,加入丙烯酸酯液体橡胶后拉伸剪切强度有显著的提高 ;液体橡胶环氧基含量和橡胶添加量对胶粘剂拉剪强度有重要的影响 ,每百份环氧树脂加 10份环氧基含量为 1.2mmol·g-1的丙烯酸酯液体橡胶 ,铝合金胶接试片拉剪强度提高了 133% ,复合材料胶接试片拉剪强度提高了 12 4 % ,4 5 # 钢胶接试片拉剪强度提高了 84 %。     

硫酸钙晶须改性环氧建筑胶的研究

采用硫酸钙晶须替代部分填料,研究其掺入量对环氧建筑胶粘度、力学性能和粘接性能的影响。结果表明,硫酸钙晶须的掺入增大了环氧建筑胶的粘度;硫酸钙晶须对环氧建筑胶具有优异的增强作用,可使环氧建筑胶的拉伸、抗弯、压缩强度分别提高34%、37%、17%;硫酸钙晶须的掺入提高了环氧建筑胶的粘接性能,拉伸剪切强度增加最大幅度可达24%。     

纳米TiO_2改性环氧丙烯酸树脂光固化胶粘剂的制备与性能研究

以环氧树脂和丙烯酸为原料制备了环氧丙烯酸酯,通过TiO_2改性环氧丙烯酸酯制备得到光固化胶粘剂用预聚物。添加混合型光引发剂TPO-L(2,4,6-三甲基苯甲酰基膦酸乙酯)和184(1-羟基-环己基-苯基甲酮)、活性稀释剂NVP(乙烯基吡咯烷酮)和TMPTA(三羟甲基丙烷三丙烯酸酯)制备得到紫外光固化胶粘剂。研究结果表明:当w(TiO_2)=4%(相对于胶粘剂总质量而言)时,胶粘剂的粘接强度最大为7.36 MPa;对比光引发剂的使用种类,发现当两种混合型引发剂m(TPO-L)∶m(184)=1∶1,w(混合引发剂)=1.9%(相对于胶粘剂总质量而言)时,胶粘剂的固化收缩率为5.56%,固化时间为5.42 s,性能较佳。     

自粘性加成型阻燃导热有机硅电子灌封胶的研制

采用端乙烯基硅油、含氢硅油为基料,氧化铝为导热填料,氢氧化铝为阻燃剂,乙烯基三甲氧基硅烷及γ-甲基丙烯酰氧基丙基三甲氧基硅烷的混合物为偶联剂,铂配合物为催化剂,三羟甲基丙烷二烯丙酯、γ-环氧丙氧丙基三甲氧基硅烷及正硅酸乙酯的反应产物作增粘剂,制备了双组分加成型阻燃导热有机硅电子灌封胶。结果表明,较佳配方为:100份端乙烯基硅油、8份含氢硅油(活性氢质量分数0.25%)、铂的质量分数15×10-6、0.05份抑制剂、150份氧化铝、30份氢氧化铝、0.5份偶联剂、3份增粘剂,所得灌封胶无需底涂剂、在90℃的加热条件下可对PC和铝材等有良好的粘接性,热导率0.8W/m.K,阻燃等级UL94V-0,能够满足大功率电子元器件的灌封要求。     

Synthesis of phenyl silicone resin with epoxy and acrylate group and its adhesion enhancement for addition-cure silicone encapsulant with high refractive index

A novel phenyl silicone resin with epoxy and acrylate group (PSREA) was successfully synthesized via the non-hydrolytic sol-gel condensation reaction of 3-glycidoxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldimethoxysilane, and diphenylsilanediol, and was employed as the adhesion promoter for addition-cure silicone encapsulant (ASE) with high refractive index. The structure of PSREA was confirmed by Fourier transform infrared spectroscopy, ¹H nuclear magnetic resonance spectroscopy, and ²⁹Si nuclear magnetic resonance spectroscopy. The influence of PSREA on the properties of ASE was studied. It was found that PSREA could markedly enhance the adhesion strength of ASE to aluminum (Al) and poly(p-phenylene terephthamide) (PPA) substrate. When the content of PSREA was 1.5 phr, the shear strength of ASE was 4.43 and 2.27 MPa for Al and PPA substrate, which was about 71 and 266% higher than that of ASE without the adhesion promoter, respectively. In addition, PSREA had little effect on the mechanical properties, refractive index, and viscosity of ASE.     

固化剂对环氧包封料性能的影响

研究了以甲基四氢苯酐和间苯二胺作固化剂时 ,环氧树脂包封料的固化放热现象 ,测定了不同固化剂体系的包封料力学性能、电性能、密度和吸水性。结果表明 ,间苯二胺的活性大于酸酐固化剂的活性 ,但填料的加入使胺固化的放热降低 ,酸酐固化的升高。胺固化的冲击强度较高 ,加入填料可提高拉伸强度。胺固化的介电常数 ,介电损耗角较高 ,但体积电阻率较低 ,其吸水性较高     

Synthesis of silane oligomers containing vinyl and epoxy group for improving the adhesion of addition-cure silicone encapsulant

Two types of silane oligomers containing vinyl and epoxy group (PTGM and PTGE) as adhesion promoters were synthesized by the reaction of trimethylolpropane monoallyl ether with 3-glycidoxypropylmethyldimethoxysilane and 3-glycidoxypropylmethyldiethoxysilane, respectively. Fourier transform infrared spectroscopy, ¹H nuclear magnetic resonance spectroscopy, and gel permeation chromatography were used to characterize their chemical structures. The effect of adhesion promoters on properties of addition-cure silicone encapsulant (ASE) with lots of alumina (Al₂O₃) particles as thermally conductive fillers was investigated. The results showed that PTGM and PTGE could significantly improve both the adhesive strength and mechanical properties of ASE. The viscosity of ASE with no more than 3.0 phr PTGM and PTGE was below 5000 mPa s so that they were suitable for encapsulating process. Observation using scanning electron microscopy revealed that PTGM and PTGE could improve the dispersion of Al₂O₃ particles in silicone rubber matrix and enhance the bond between the particles and the matrix.     

Synthesis of a boron-containing adhesion promoter for improving the adhesion of addition-cure silicone rubber to PPA

Abstract

In this study, a boron-containing adhesion promoter PhBSiO with a high refractive index and MeBSiO with a low refractive index were synthesized by a non-hydrolytic sol-gel reaction. The chemical structures of the synthesized adhesion promoters were firstly characterized by infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC). Then, the effects of adhesion promoters on the bonding properties of the cured silicone rubber were analyzed and the compatibility of the adhesion promoters to the silicon rubber was further studied through light transmittance detection. The boron-containing silicone adhesion promoters significantly enhanced the bonding strength of the cured silicone rubber to poly-phthalamide (PPA). When the addition amounts of PhBSiO and MeBSiO was 3.0 phr, the shear strength between silicone rubber and PPA respectively reached 0.761?MPa and 0.809?MPa, which were 145% and 161% higher than that of silicone rubber without adhesion promoter. In addition, the adhesion mechanism of the boron-containing adhesion promoter was investigated. The microscopic morphology of the fractured surface of the cured silicone rubber further demonstrated that boron atoms in the adhesion promoters significantly improved the adhesion strength between silicone rubber and PPA.     

Silane Coupling Agents as Adhesion Promoters for Aerospace Structural Film Adhesives

The performance of eight organofunctional silane coupling agents as adhesion promoters for the bonding of aluminium with two 121°C and two 177°C curing structural film adhesives was investigated and compared to the chromic acid (FPL) etch pre-treatment process and two non-chemical pretreatments. Aspects considered were shear strength of joints at ambient and elevated temperatures and durability, as judged by the wedge test.

The epoxy silane, γ-glycidoxypropyltrimethoxy silane, was found to be a very efficient adhesion promoter with all film adhesives evaluated. The cationic styryl silane, a neutral diamine monohydrochloride, showed promise with two adhesive systems. Four other neutral silanes were less effective.

Performance of amine functional silanes was mixed. Although the shear strength of joints with the primary amine silane at its natural pH of ∼10.3 was relatively good, durability was poor. However, good durability was obtained if the primer was first adjusted to pH 8 with hydrochloric acid, but not if acetic or phosphoric acids were used. Diamine silane was not an effective adhesion promoter at either its natural pH or when acidified with hydrochloric acid.     

The synthesis,characterization and properties of silicone adhesion promoters for addition-cure silicone rubber

Two types of polysiloxanes, GVPMS and GVHMS, were synthesized through nonhydrolytic sol-gel reaction from vinyltrimethoxysilane(VTMS), 3-glycidoxypropyltrimethoxysilane(KH560) and diphenylsilandiol(DPSD) or hydroxyl silicone oil, respectively. The chemical structures were characterized by Fourier transform infrared (FTIR) spectroscopy, ¹H nuclear magnetic resonance (¹H-NMR) spectroscopy and gel permeation chromatography (GPC). GVPMS and GVHMS were used as adhesion promoter for addition-cure silicone rubber. It was found that the adhesion promoters not only greatly improved adhesion strength but also had excellent compatibility with silicone rubber. Among them, GVPMS gave better adhesion strength in silicone rubber. The shear strength of silicone rubber reached 1.70 MPa with addition of 1.5 phr GVPMS, which was about 317% higher than that of silicone rubber without the adhesion promoter. Meanwhile, the shear strength of silicone rubber reached 1.14 MPa with addition of 2.0 phr GVHMS, which was 183% higher than that of silicone rubber without the adhesion promoter. Optical property test results revealed that the refractive indexes of GVPMS and GVHMS were 1.5185 and 1.4133 respectively and both of them had good compatibility with silicone rubber, which satisfied the application demand of high-refractive and low-refractive electron encapsulation. Thermal resistance test and SEM results further proved that adhesion promoter could significantly increase the adhesion between the copper substrate and silicone rubber, in which GVPMS had a better performance. Oxidation treatment experiment further explained the mechanism that adhesion promoter functioned as a bridge, linked silicone rubber and copper substrate through chemical bonds.     

聚氨酯改性环氧树脂胶粘剂的制备及性能研究

由端-NCO基聚氨酯(PU)预聚物与环氧树脂反应,制备了PU接枝改性环氧树脂。着重探讨了PU预聚物的含量、活性稀释剂的含量和异氰酸酯结构等因素,对改性环氧树脂的粘度和粘接性能的影响。实验结果表明,该改性环氧树脂的粘度随着PU预聚物含量的增加而逐渐增大,随着活性稀释剂含量的增加而逐渐降低,而且在相同的条件下,用不同的二异氰酸酯改性环氧树脂的粘度大小次序为:IPDI型>MDI型>TDI型;该改性环氧树脂在PU预聚物含量为20%时,对铝片/铝片的剪切强度最大(7.82 MPa);在PU预聚物含量为10%时,对铁片/铁片的剪切强度最大(11.70 MPa),而且TDI型和IPDI型改性环氧树脂的粘接性能明显好于MDI型改性环氧树脂。     

Strength of Epoxy/Glass Interfaces after Hygrothermal Aging

The stability of epoxy/glass interfaces subjected to hygrothermal aging was assessed using a fracture-mechanics approach. An epoxy system consisting of diglycidyl ether of bisphenol F cured with 2-ethyl-4-methyl-imidazole was bonded to borosilicate glass adherends that were treated with various types of adhesion promoters to provide a variety of interfaces. Adhesive strength was measured under dry, as-processed conditions and as a function of exposure time to an 85°C/85% relative humidity (RH) environment. As expected, the strain-energy-release rate, G_c, dropped significantly with aging time for the bare epoxy/glass interface. The drop in G_c is assumed to be due to a loss of interfacial forces. The use of two silane-based adhesion promoters, 3-aminopropyltriethoxysilane (APS) and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECH) resulted in improved adhesive strength both before and after hygrothermal aging. The improvement in adhesive strength can be explained by the introduction of chemical bonds at the interface. The drop in G_c is assumed to be due to a loss of interfacial forces and hydrolysis of siloxane bonds. In addition to the use of organosilane-based adhesion promoters, a series of polyhydroxyaminoethers (PHAE) thermoplastic adhesive resins was also investigated as potential adhesion promoters. It was found that 2% PHAE in Dowanol® PM, a hydroxyl-group-containing solvent, was the best system for the PHAE-based adhesion promoters. Interestingly, both the acetic acid concentration in the solvent and maleic anhydride content in the PHAE resin were shown to affect the adhesive strength.     

改性剂对环氧灌封胶性能的影响

研究了增韧剂、稀释剂及促进剂对环氧灌封胶性能的的影响。以聚氨酯为增韧剂,断裂伸长率较未增韧体系提高80.8%;以502树脂为稀释剂,降低了体系黏度,对断裂伸长率和模量影响不大,断裂强度稍有降低,但剪切强度有所提高,冲击强度则可提高53.1%;以间苯二酚为固化促进剂缩短了剪切强度达到峰值的时间,且峰值强度略有增加。