原料配比对间苯二酚-甲醛气凝胶性能的影响

Effects of raw material ratio on performance of resorcinol-formaldehyde aerogel

为获得较低热导率和较高强度的高性能隔热材料,通过常压干燥制备间苯二酚-甲醛(RF)气凝胶,研究了原料配比对气凝胶性能的影响规律。结果表明:催化剂浓度减小,气凝胶密度和收缩率减小,同时强度降低;反应物浓度减小,气凝胶密度和收缩率增大,强度也增大,但热导率降低。制备的气凝胶最大密度为0.847 1 g/cm^3,弯曲强度提高18.2倍(从1.22 MPa增至22.26 MPa),较佳热导率为0.058~0.076 W/(m·K)。

In order to acquire thermal insulators with low thermal conductivity and high strength,resorcinol-formaldehyde（ RF） aerogel was prepared through atmospheric drying. The effects of material ratio on performance of RF aerogel were investigated. Results showed that both the shrinkage and density of RF aerogel decreased and the strength reduced with decreasing catalyst concentration. With decreasing reactant concentration,and density,and shrinkage,the strength of RF increased. The maximum density of aerogel was 0. 847 1 g / cm^3 while the bend strength increased by 18. 2 times（ from 1. 22 MPa to 22. 26MPa）,and the suitable thermal conductivity was 0. 058-0. 076 W /（ m·K）.