PDMS–OH嵌段PF对PF泡沫压缩及热学性能的影响

引入不同质量分数的端羟基聚二甲基硅氧烷(PDMS–OH)对酚醛(PF)泡沫进行共混改性。从两相聚合物相容的角度,分析PDMS–OH对PF泡沫压缩及热学性能的影响。通过宏观沉淀实验,分析发泡用PF/PDMS–OH共混体系的相容性及稳定性。采用动态热力学分析仪表征改性的PF树脂样条的玻璃化转变温度,分析PDMS–OH与PF的相容效果。通过压缩性能测试分析PDMS–OH对PF泡沫压缩性能的影响及机理。通过热失重分析仪分析PF泡沫复合材料的热稳定性。结果显示,加入15%的PDMS–OH在一定程度上增加了体系的交联密度,相容效果最佳,压缩强度和压缩弹性模量分别提高了280%和285%,表现出最优的热稳定性。

Effect of PDMS-OH Modified PF on Compression and Thermal Properties of PF Foam

The phenolic foams (PF) were modified by different content of terminal hydroxyl dimethyl-polysiloxane (PDMS-OH).The effect of PDMS--OH on compression and thermal properties of PF were analyzed according to the compatibility of polymers.The compatibility and stability of PDMS-OH/PF blends were studied by sedimentation experiment.The temperature of glass transition (Tg) was measured though dynamic mechanical analyzer to explain the impact on compatibility of PF and PDMS-OH.The compression property and mechanism were discussed from the data of compression test.The thermal property were obtained from thermal degradation analyzer to compare the thermal stability of PF composites.The results show that the phenolic blend with the 15％ PDMS—OH has the increased cross-link density,better compatibility and outstanding thermal stability.The compression strength and modulus are improved by 280％ and 285％ respectively.