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以碳酸钠为催化剂,首先利用苯酚和甲醛水溶液合成水杨醇,水杨醇进一步与硼酸反应生成硼改性PF(酚醛树脂);然后以残炭率为考核指标,采用单因素试验法探讨了催化剂类型、醛酚比、硼酚比和合成水杨醇的反应时间等对硼改性PF性能的影响,并优选出制备硼改性PF的最佳工艺条件。研究结果表明:当合成水杨醇的反应时间为2.0 h、n(苯酚)∶n(甲醛)∶n(硼酸)=1∶(1.7~2.0)∶0.3和以碳酸钠作为催化剂时,硼改性PF的800℃残炭率(65.88%)相对最高,由其制成的异型Si3N4结合SiC材料和捣打料均具有良好的应用性能。
Sodium carbonate as a catalyst, the first use of phenol and formaldehyde aqueous salicylol synthesis, salicyl alcohol further reaction with boric acid to generate boron-modified PF (phenolic resin); and then the carbon residue rate as an assessment index, the use of single factor test method The type of catalyst, the ratio of phenol to phenol, the ratio of boron to phenol and the reaction time of the synthesized salicyl alcohol on the properties of boron-modified PF were studied. The optimum conditions for the preparation of boron-modified PF were optimized. The results showed that when the reaction time of synthesis of salicyl alcohol was 2.0 h and the molar ratio of n (phenol): n (formaldehyde): n (boric acid) = 1 (1.7-2.0): 0.3 and sodium carbonate as catalyst, The PF of 800 ℃ charcoal residue rate (65.88%) is relatively the highest, made of its special-shaped Si3N4 bonded SiC material and Ramming material has good application performance.