硼改性酚醛泡沫复合材料的制备与性能研究

为改善酚醛泡沫的耐高温性能，实验将适量的B2O3引入酚醛泡沫，经模压成型、固化后，制备出硼改性酚醛泡沫复合材料；研究了硼改性酚醛泡沫复合材料的微观结构，以及不同的硼含量对酚醛泡沫的压缩性能、耐高温性能的影响。结果表明，硼改性酚醛泡沫的压缩断裂特征为假塑性断裂模式；引入适量的B2O3，可改善树脂基体相的韧性，提高酚醛泡沫复合材料的压缩强度，当B203含量为质量分数4％时，酚醛泡沫的压缩强度最大，为10．14MPa，比纯酚醛泡沫提高了5．18％。硼改性有利于酚醛泡沫的高温稳定性，酚醛泡沫的热分解温度和残碳率均随硼含量的增加而有所提高；当B2O3含量为质量分数7％时，酚醛泡沫的耐高温性能最优，其失重10％时的热分解温度为447℃，比纯酚醛泡沫提高了76．68％；其800℃下的残碳率为66．37％，较纯酚醛泡沫高出16．05％。

Preparation and Properties of Boron-Modified Phenolic Foams Composites

Abstract： In order to improve high temperature resistance of phenolic foams, B203 was incorporated in it to synthesize boron-modified composites by mold forming and curing. Microstructure of resultant phenolic foams were studied. Effects of boron content on compressive properties and high temperature resistance of phenolic foams are investigated. The results showed that compressive fracture characteristics of boron modified phenolic foams was pseudoplastic. Toughness of resin matrix and compressive strength of phenolic foams could be improved by proper amount of B2O3. The compressive strength of PF-4 is best, 10. 14 MPa, 5.18% higher than PF-0. Boron was beneficial to improving high temperature stability of phenolic foams. Thermal decomposition temperature and carbon yield are enhanced with increase of B203. PF-7 showed better high temperature stability than others, whose thermal decomposition temperature with 10% weight loss is 447 ℃, 76.68% higher than that of PF-O, and carbon yield is 66.37% at 800 ℃, 16.05% higher than that of PF-O.