复合催化剂改性矿用酚醛树脂低热值及发泡性能研究

Study on low calorific value and foaming property of phenolic resin modified by compound catalyst

传统酚醛树脂在煤矿充填堵漏过程中会释放大量反应热,易造成充填煤层区域温度的升高,从而引起煤炭自燃的问题。针对这一技术问题,对合成酚醛树脂的关键组分“碱性催化剂”进行改良,制备出“碱性催化剂A”,对比分析了催化剂A和其他碱性催化剂对树脂黏度、固含量、泡沫固化温度、发泡倍率和微观孔径结构的影响,并探究了由催化剂A合成的改性酚醛树脂(N-PF)的固化放热机理。研究结果表明:N-PF树脂具有较高的发泡倍率,良好的黏度和较低的固化温度。微观孔径数据显示,碱性催化剂A的应用提高了N-PF树脂泡沫体的孔隙尺寸,且泡沫粉化率低于PF泡沫,具有更加优异的力学性能;傅里叶变换红外吸收光谱(FT-IR)和核磁共振碳谱(^(13)C-NMR)数据显示,N-PF的羟甲基指数低于PF,有利于酚醛树脂在固化过程中总放热量的降低;差示扫描量热(DSC)分析和理论计算证明N-PF在固化过程中的热量释放较PF更为平缓,避免了热量的快速积聚。同时发现,与PF相比N-PF在相同固化体系下的固化体温度与发泡体周围环境温度均大幅降低,固化体温度由125℃降低至65℃降幅可达46%,发泡体周围环境温度由41.8℃下降至32.9℃降幅达21%。

Traditional phenolic resin will release a large amount of reaction heat in the process of coal mine filling and plugging,which is easy to cause the temperature rise in the filled coal seam area,resulting in the problem of coal spontaneous combustion.In view of this technical problem,the key component of phenolic resin synthesis“basic catalyst”was improved in this paper,“Basic catalyst A”was prepared.The effects of catalyst A and other basic catalysts on resin viscosity,solid content,foam curing temperature,foam ratio and mi⁃croscopic pore structure were compared and analyzed.The curing exothermic mechanism of modified phenolic resin(N-PF)synthesized from catalyst A was explored.The results show that N-PF resin has higher foaming rate,better viscosity and lower curing temperature.The micropore size data showed that the application of alkaline catalyst A increased the pore size of N-PF resin foam,and the foam powder rate was lower than that of PF foam,with better mechanical properties.FT-IR and ^(13)C-NMR data showed that the hydroxymethyl index of N-PF was lower than that of PF,which was beneficial to the reduction of total heat release during the curing process of phenolic resin.Differential scanning calorimetry(DSC)analysis and theoretical calculation show that the heat release of N-PF during curing process is more gentle than that of PF,avoiding the rapid heat accumulation.At the same time,it was found that the temperature of the cured body and the ambient temperature of the foaming body of N-PF under the same curing system were significantly reduced,the temperature of the cured body decreased by 46%from 125℃to 65℃,and the ambient temperature of the foaming body decreased by 21%from 41.8℃to 32.9℃.