酸固化剂对酚醛泡沫微观结构的影响

Effect of Acid Catalyst on the Microstructure of the Phenolic Foam

以苯酚、甲醛为主要原料合成了可发性酸催化酚醛树脂，并加入匀泡剂、发泡剂和固化剂制备了酚醛泡沫。通过电子扫面显微镜（SEM）观察了泡沫的微观结构；讨论了不同酸固化剂及其用量在树脂发泡过程中所起的作用，以及对酚醛泡沫微观结构的影响。结果表明：在优化的树脂体系下，当采用硫酸作为同化剂，控制加入量，可以得到孔径介于65—85μm的泡沫，闭孔率均小于10％；当采用对甲苯磺酸作为固化剂，控制加入量，可以得到孔径介于95～110μm的泡沫，闭孔大90％。并且通过磷酸苯酯与硫酸复配作为固化剂，保证孔径大约65μm的前提下，有效地改善了泡沫孔壁缺陷，得到了小径细腻的酚醛泡沫。

Phenolic resin was synthesized mainly from phenol and formaldehyde as raw material, The phenolic foam was prepared by adding foam stabilizer, foaming and curing agent. The microstructure of the phenolic foam was investingated by SEM. The effect of different acid catalyst and their content on foaming process as well as the microstructure of the phenolic foams was discussed. The results showed that ： in the optimized resin system, the diameter of foam was 65-85μm with sulfuric acid as curing agent, the closed cell content was less than 10%. The diameter of foam was 95-110 μm with PTSA as curing agent, the closed cell content was more than 90%. The flaw of foam cell wall was effectively improved and the diameter of foam was about 65 μm when sulfuric acid and phenyl phosphate was used as composition acid catalyst, and the phenolic foam with small cell diameter was got.