丙二酸二乙酯与邻苯二甲酸二烯丙酯复合改性酚醛树脂

Phenolic resin modified by diethyl malonate and diallyl phthalate

以甲醛和苯酚为原料、有机酯[由丙二酸二乙酯和DAP(邻苯二甲酸二烯丙酯)组成]为改性剂,制备碱性PF(酚醛树脂);然后采用DMA(动态热机械分析)法、DSC(差示扫描量热)法、FT-IR(红外光谱)法和TGA(热失重分析)法等对改性PF的固化机制、反应动力学等进行了表征和分析。研究结果表明:随着有机酯用量的不断增加,改性PF的储能模量、损耗模量和损耗因子(tanδ)无明显的规律性,固化温度随之下降;有机酯可促进改性PF的凝胶固化,并且是通过快速促进PF分子的活性中间体亚甲基醌来实现的。有机酯用量虽对改性PF的耐热性影响不大,但相应胶合板的胶接强度有所降低;当m(有机酯)=12 g、m(丙二酸二乙酯)∶m(DAP)=1∶1时,改性PF的综合性能相对最好。

With formaldehyde and phenol as raw materials, organic ester[consisted from diethyl malonate and DAP （diallyl phthalate）] as modifier, an alkaline PF （phenolic resin） was prepared. Then, the curing mechanism and reaction kinetics of modified PF were characterized and analyzed by DMA （dynamic thermal mechanical analysis） , DSC （differential scanning calorimetry） , FT- IR （infrared spectroscopy） and TGA （thermogravimetric analysis） methods. The research results showed that the storage modulus, loss modulus and loss factor （tan 8） of modified PF had no obvious regularity but curing temperatures were dropped with increasing organic ester contents. The organic ester could accelerate gel and curing of modified PF, which was realized by quickly promoting reactive intermediates （namely methylene quinone） in PF molecules. The influence of organic ester contents on the heat resistance of modified PF was little, but the bonding strength of corresponding plywood was accordingly decreased. The combination property of modified PF was relatively best when mass of organic ester was 12 g, mass ratio of m（diethyl malonate）：m（DAP） was 1 ： 1.