氟橡胶/三元乙丙橡胶密封材料的制备及性能研究

Research on Properties and Preparation of Fluoroelastomer/EPDM Sealing Materials

氟橡胶(FKM)具有耐高温、耐化学腐蚀以及摩擦因数和表面能较低等特点,是一种在特殊环境有较高应用价值的密封材料,但其弹性和耐寒性能较差、加工性不良,且价格昂贵。采用三元乙丙橡胶(EPDM)与其并用,可在改善低温和加工性能的同时,降低成本。通过万能材料试验机、阿克隆磨耗仪及老化箱考察硫化体系、FKM/EPDM配比及吸酸剂对硫化胶的耐磨、耐腐蚀、耐油等性能的影响。结果表明:采用双硫化体系能获得性能良好的FKM/EP-DM并用硫化胶;当FKM/EPDM并用胶的配比为3∶1,双酚AF质量分数为2.5%,BPP为0.4%,DCP为1.5%,TAIC为4%时,能充分发挥EPDM的优势,FKM的性能得到改善,同时成本降低;高活性氧化镁(吸酸剂)的加入,减少了在硫化过程中大分子的降解,可提高硫化胶的性能,其较佳用量为1.5%。

Fluorine rubber is a common sealing material with high practical value in the special environment, and it has excellent properties such as high temperature resistance, chemical corrosion resistance, low friction coefficient and low sur- face energy. But, fluorine rubber also has some defeets, such as poor elastic, bad cold-resistant and processing performanee, and high price. To improve the low temperature and processing performance, at the same time reduce the cost, the fluorine rubber was modified by blending with ethylene-propylene-diene monomer（EPDM）. The influences of vulcanization euring system, acid-acceptor and FKM/EPDM blends ratio on wear resistance, corrosion resistance, oil resistance and other prop- erties of blend vulcanizates were examined by the universal material testing machine, Akron abrasion tester and aging bak- er. The results show that, FKM/EPDM blend vulcanizates with good performance are obtained by using dual curing system; when FKM/EPDM blend ratio is 3：1 ,the weight content of bisphenol AF is 2. 5% ,BPP is 0. 4% ,DCP is 1.5% ,TAIC is 4% ,the advantages of EPDM can be given full play,the performances of FKM is improved,at the same time the cost is reduced;the degradation of maeromolecules is reduced by adding some high active magnesium oxide（ acid absorbent） vulcanization,the properties of vulcanizates can be improved, and its optimum using amount is 1.5%