新型抗烧蚀酚醛树脂的研究

Study on a New-type Ablative Phenolic Resin

采用不同的甲醛 (F) /苯酚 (P)比和复合碱性催化剂合成了邻对位羟甲基比例 (o/ p)不同的酚醛树脂。利用该酚醛树脂中邻对位交联程度变化 ,可以优化炭化过程中苯醌式结构中间体稠环化历程 ,从而通过适当调整酚醛树脂受烧蚀而发生炭化时的交联密度 ,使炭化过程稳定 ,高温下易于石墨化 ,提高了抗烧蚀性能。 F/ P比在 1.6～ 1.8时 ,纯酚醛树脂的炭化率与玻璃纤维 /酚醛树脂复合材料的质量烧蚀率变化较小 ,烧蚀形貌显著改善 ,是比较理想的配料比。

Phenolic resins which had various orth/para hydroxy methyl ratios were synthesized by use of complex alkali catalysts and under various ratios of formaldehyde/phenol The fused ring transition mechanism of carbonization of phenolic resin could be optimized by altering the orth/para crosslink degree, the course of carbonization could go slowly and steadily, and the char yielded show a high tendency towards graphitization under high temperature, and so ablative ability could be improved When the formaldehyde/phenol ratios were in 1 6～1 8,the phenolic resins′ ablation morphological appearances were ameliorate, and their char yields and ablation rates of the composite were relatively ideal