化学反应型高黏沥青的制备与性能评价

为简化高黏沥青的制备流程、提高生产效率及降低改性剂掺量,基于自主研发的化学反应型改性剂研究了高黏沥青的宏微观性能。采用纯搅拌工艺进行了化学反应型高黏沥青的制备,通过基础物理指标及红外光谱结果完成了反应时长的优选;分析了不同改性剂掺量下化学反应型高黏沥青的微观形貌、改性机理及性能变化规律,并结合高黏沥青混合料的路用性能测试,完成了改性剂掺量的优选。结果表明:化学反应型高黏沥青可以采用纯搅拌工艺制备,其宏观性能和热存储稳定性优异,相应的沥青混合料也具有路用性能优势;建议的搅拌时长为3 h,建议的改性剂掺量为沥青质量的7%~8%。

Bismaleimide Modified by Allyl Novolak for Superabrasives

A novel thermosetting resin system for superabrasives based on novolak and bismaleimide （BMI） was developed. The novolak resin was allylated and then copolymerized with BMI. The structure of allyl novolak and reaction mechanism were analyzed by FFIR. Thermal and mechanical properties were characterized by using com- prehensive thermal analyzer （DSC-TG） and strength tester, respectively. The results showed that high molecular weight of novolak was advantageous for heat-resistance, but was unfavorable for the bending strength. High allyl content improved the heat-resistance but lowered the bending strength. When the molecular weight of novolak was 450 and allyl content was 50%, the best resin system with good heat-resistance and bending strength was obtained. It was suitable for the manufacturing of superabrasive tools.

潜伏型环氧树脂固化剂研究进展

环氧树脂具有优异的综合性能,潜伏型环氧树脂固化剂与环氧树脂配合后具有良好的贮存稳定性,在胶黏剂、涂料、电子封装和复合材料等领域具有巨大的应用需求和商业价值。潜伏型固化剂的种类很多,按照固化剂主体不同可分为双氰胺、酰肼、酸酐、苯并噁嗪和氨基酸类化合物,咪唑和改性胺类化合物,硼胺络合物与重氮盐、碘鎓盐和锍鎓盐化合物。为了便于指导潜伏型固化剂的设计与使用,本文按照潜伏机理不同将当前报道的潜伏型固化剂分为热溶解型、化学改性型和微胶囊型固化剂三大类,并对其研究进展进行了分类概括与讨论;同时总结了当前评价固化剂潜伏性能的方法;最后对当前潜伏型固化剂的优缺点进行了总体评价,并对潜伏型固化剂的未来发展趋势进行了展望。