一种UV固化聚硫代醚密封胶的制备与性能研究

利用巯基-乙烯基"点击"反应制备了一种UV(紫外光)固化聚硫代醚密封胶。探讨了引发剂、填料等对UV固化聚硫代醚密封胶的固化深度、拉伸性能和粘接性能等影响。研究结果表明:与室温固化聚硫代醚密封胶相比,UV固化聚硫代醚密封胶具有固化速率较快、固化过程几乎不受环境影响等优势;UV固化聚硫代醚密封胶的力学性能良好,具有稳定的粘接性能,并且其耐高温性能比聚硫密封胶更优异。     

聚硫密封胶耐老化性能研究

以环氧改性液体聚硫密封胶为基胶,研究了环氧树脂、液体聚硫橡胶、填料、防老剂种类及用量对聚硫密封胶常温拉伸性能及老化后拉伸性能的影响.结果表明,通过环氧改性聚硫橡胶,可有效提高聚硫密封胶的扯断伸长率及耐热老化性能.填料对聚硫密封胶均有一定的补强效果,炭黑的补强效果最好,A-380的耐热老化性能最好.防老剂D可有效提高聚硫...     

改性聚硫密封胶的制备及性能研究

为提高聚硫密封胶与金属的粘接性能,以EP(环氧树脂)和PF(酚醛树脂)作为聚硫密封胶的复合增黏树脂,并着重探讨了增黏树脂配比对聚硫密封胶制备工艺、力学性能及粘接性能等影响。研究结果表明:当m(EP)∶m(PF)=10∶10时,聚硫密封胶的综合性能相对较佳,此时其拉伸强度、断裂伸长率和180°剥离强度分别为2.26 MPa、338%和1.95 kN/m。     

耐高温液体改性聚硫橡胶的制备及性能

通过双酚A环氧树脂对液体聚硫橡胶进行化学改性,在液体聚硫橡胶分子结构中引入适量的苯环耐高温链段,制备了可室温硫化的耐高温液体改性聚硫橡胶,并对改性后聚硫橡胶的性能进行了研究。研究结果表明:改性后聚硫橡胶的分子量和黏度略有提高,耐热降解温度可提高10℃以上,但低温性能会有一定程度提高,需合理控制环氧树脂的量。以改性聚硫橡胶为基体的密封剂具有良好的耐高温性能和粘接性能,但随着改性环氧树脂量的增加,密封剂断裂伸长率随之降低,剥离强度呈现先增后降的趋势。     

用氧化锌硫化液态聚硫橡胶

文中研究了制造白色和彩色液态聚硫密封胶新的硫化体系的组成和使用方法。此外．还论述了氧化锌，环氧树脂的用量对密封胶性能的影响。     

木质素填充聚硫密封胶的性能研究

以天然高分子木质素为主要填充剂制备了聚硫密封胶,考查了木质素用量对聚硫密封胶力学性能及粘接性能的影响。结果表明,当木质素用量为100份时,聚硫密封胶的综合性能相对较好,其拉伸强度、断裂伸长率和180°剥离强度分别为3.94 MPa、620%和5.6 k N/m。该聚硫密封胶还具有较好的抗老化性能和耐腐蚀性能。     

一种耐高温聚硫代醚密封胶的合成及其应用

利用巯基与炔基之间的"点击反应"合成了一种含柔软侧基的液体聚硫代醚橡胶,并对其理化性能进行了探讨。研究结果表明:该液体聚硫代醚橡胶的数均相对分子质量(Mn)为3 200,玻璃化转变温度(Tg)为-72.38℃,并且其低温柔韧性极佳;以该液体聚硫代醚橡胶作为生胶,其与碳酸钙等填料复配后作为基膏,以二氧化锰作为硫化剂,可制备出一种耐高温性和耐介质性良好的密封胶;与普通聚硫密封胶相比,该液体聚硫代醚密封胶具有更优异的热空气老化性能。     

植酸对聚硫密封胶阻蚀性能的影响研究

以液体聚硫橡胶为基体、炭黑为补强剂和植酸为阻蚀剂,制备了阻蚀型聚硫密封胶。着重考察了植酸含量对聚硫密封胶活性期、力学性能、粘接性能以及阻蚀性能等影响,并探讨了植酸的阻蚀机制。研究结果表明:当w(植酸)=4%(相对于密封胶质量而言)时,植酸对密封胶活性期和力学性能的影响较小,并且该密封胶兼具了良好的阻蚀性;植酸与钢中的Fe元素形成不稳定的络合物,可在一定程度上提高聚硫密封胶的阻蚀性能。     

环氧树脂对液体聚硫橡胶粘接及力学性能的影响

通过对密封剂180°剥离、拉伸试验、热空气老化及耐高温、耐油等测试,研究了不同类型环氧树脂以及环氧树脂用量对聚硫密封剂粘接性能、耐高温空气和耐高温燃油性能的影响,并对其机理进行讨论。结果表明,酚醛环氧树脂具有较好的增黏和增强效果,添加量为2～3份时,密封剂与铝合金基材间的破坏形式为100%内聚破坏,力学性能、耐热性能及耐油性能最佳。当其添加量继续增加时,密封剂性能逐渐下降。     

改性聚硫密封胶的研制

以自制的改性聚硫液体橡胶为原胶,配以增塑剂、填充剂、触变剂制备了双纽分改性聚硫密封胶。研究表明,改性聚硫密封胶与混凝土的粘接性优于聚硫密封胶。讨论了聚硫橡胶含量对密封胶性能的影响,结果表明随着原胶含量的增加,密封胶的力学性能先增加后减小,当原胶质量分数为40％时,力学性能最优;讨论了密封胶A组分的贮存稳定性的影响因素,发现填料的pH值是影响A组分贮存稳定性的主要因素。     

环氧树脂硫化聚硫醚密封剂的性能研究

以液体聚硫醚橡胶作为密封剂的生胶、环氧树脂(EP)作为硫化剂,成功制备出一种综合性能良好的新型聚硫醚密封剂。结果表明:聚硫醚橡胶的热分解温度(296.4℃)高于聚硫橡胶(281.0℃),热循环后聚硫醚密封剂的拉伸强度变化率或断裂伸长率变化率(31%或42%)均低于聚硫密封剂(45%或64%),说明前者的耐高温性能优于后者;聚硫醚密封剂对多种基材表现出稳定的粘接性能,其常温剥离强度均超过7.5 kN/m(均为内聚破坏),并且其在60℃盐水/航空煤油双层液中浸泡7 d后仍为内聚破坏;聚硫醚密封剂受温湿度影响较小,其硫化速率较大,并且其硫化效果和加工性能良好。     

The effect of epoxy resin to reduce the compression set of polysulfide sealant

In this article, modified polysulfide sealants with lower compression set were prepared by a simple method of introducing the diglycidyl ether of bisphenol A resin (DGEBA epoxy resin) into sealants. The investigation on reactivity analysis and gel faction test verified that the incorporation of epoxy resin in sealants was just a blending process rather than copolyaddition with polysulfide resin. Stress–strain behavior during compression revealed that the epoxy resin could reduce the compression stress when the sealants were loaded to a certain strain, which effectively lessened crosslink breakages and benefited to compression resistance. Also the rigid phenyl structure in epoxy resin may retard incidental slide between polysulfide chains and prevent interchange reactions between disulfide linkages. The incorporation of 2 phr epoxy resin distinctly reduced compression set of polysulfide sealant from 28.3% to 11.2% after compressed 25% at 23°C for 1 day. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Compression set property and stress–strain behavior during compression of polysulfide sealants

In this article, mechanical and compression set properties, swelling property, and stress–strain behavior during compression of polysulfide sealants based on different polysulfide resin were investigated. The results showed that molecular weight and cross‐linking agent of liquid polysulfide resin had significant influence on mechanical and compression set properties of the sealants. The sealants based on higher molecular weight polysulfide resin had higher mechanical properties. At the same time, lower cross‐linking agent in polysulfide resin produced lower cross‐link density and higher swelling property, which resulted in higher compression set value of the sealant. However, when different molecular weight polysulfide resins were used in the sealant simultaneously, the testing results indicated that the compression performance of the sealants was significantly enhanced, while mechanical properties of the sealants kept nearly unchanged. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

导电聚硫密封剂研究

随着电子行业的飞速发展,电子设备对电磁环境的要求也更加苛刻,电子设备箱的密封需要使用具备导电功能的密封剂。本文研究了导电炭黑对聚硫密封剂导电性能和力学性能的影响,确定了导电炭黑在聚硫密封剂中的最佳用量,还研究了热空气老化对导电聚硫密封剂性能的影响。结果表明,研究的导电聚硫密封剂可以在高温环境中使用。     

Modification of polysulfide sealant with polysulfide polythio‐urethane‐urea

With a small amount of isocyanate‐terminated polysulfide (NCO‐PSF‐NCO) as additive, the commercial polysulfide‐based sealant had significant improvement in mechanical properties. The test results showed that 5% of NCO‐PSF‐NCO could help to rise 50% in the tensile strength and 27% in the ultimate elongation of the polysulfide sealant. The adhesive strength to substrates such as steel, epoxy‐coated or polyurethane‐coated surface also increased significantly. Dynamic mechanical thermal analysis and differential scanning calorimetry analysis revealed that formed polysulfide polythio‐urethane‐urea (polysulfide‐urea) contributed to a slight increase in the T_g of the polysulfide sealant. It might be due to the domains of polysulfide‐urea, which had effects of physical crosslinking and chain‐extending on the polysulfide sealant. However, the introduction of polysulfide‐urea structures had no appreciable influence on oil resistance of the polysulfide sealant. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

液体聚硫橡胶对聚硫密封剂性能的影响

以G系列液体聚硫橡胶为生胶、MnO2为密封剂的硫化剂,制备相应的聚硫密封剂。考察了生胶的不同相对分子质量(Mr)和交联度对相应密封剂性能的影响。结果表明:不同Mr或交联度的生胶均赋予相应密封剂良好的力学性能,特别是由低Mr的G44制成的密封剂具有相对更好的力学性能;密封剂的耐高温性能与生胶的Mr关系不大,主要受交联度影响较大;生胶的Mr越大或交联度越高,密封剂的耐水性越好,但Mr或交联度对密封剂的耐油性能(增重率<3%)和粘接性能影响较小。     

酚醛改性聚硫密封剂的研制

本文介绍了酚醛树脂，聚硫密封剂的制备，酚 醛树脂改性聚硫橡胶的研究。     

绝热层环氧树脂体系增韧和低温性能研究

探讨了端羧基丁腈橡胶(CTBN)、聚硫橡胶2种因素对环氧树脂体系低温韧性的影响,并对他们的影响规律作了初步研究,结果表明,丙烯腈含量为13%左右的CTBN对环氧树脂体系低温增韧效果显著。     

350℃快固高强度密封胶的研制

研制一种耐热高强度环氧树脂密封胶,固化条件为瞬间达到350℃下固化10min,用于形状记忆合金收缩套管连接处的密封。该密封胶固化后室温剪切强度达到29．8MPa,能够耐40MPa的液压。该密封胶采用改性苯胺为固化剂,使用活化处理的石棉对密封胶进行包埋保护,有效地防止密封胶因高温热氧化出现烧结现象。高温下可以在形状记忆合金收缩的同时固化。