摘要
以三聚氰胺、甲醛和苯酚为原料,采取独特的合成方法制备出特殊结构的含氮酚醛树脂(N-PF),树脂中三聚氰胺的所有活性点均与苯酚相连并表现出热塑性,用元素分析、核磁共振和红外光谱进行了结构确证,并通过热重差热联用分析仪测试其热性能。制备该类型含氮酚醛树脂的关键:首先用甲醛和三聚氰胺以摩尔比3∶1制得三羟甲基三聚氰胺(TMM),然后加入过量的苯酚在接近中性条件下进行缩聚反应(95℃/48 h),苯酚与TMM的摩尔比至少在8∶1以上。利用本法制备的含氮酚醛树脂,含氮量高(≥21%),相对分子质量分布极窄,分子结构规整,无残留的不稳定羟甲基,三聚氰胺和酚醛树脂全部结合在一起,无各自游离成分存在。将其作为固化剂固化含磷环氧树脂,并对固化物的阻燃性、耐热性和电绝缘性能进行了初步研究。
A special nitrogen-containing phenolic-formaldehyde resin（ N-PF） with excellent thermoplastic properties was prepared from phenol,formaldehyde and melamine such that all the reactive sites of melamine were linked to phenol. Elemental analysis,1H-NMR and FT-IR provide proof of structure,and TG analysis confirms its excellent thermal properties. The keys to the N-PF synthesis are using a 3∶ 1 mole ratio of formaldehyde and melamine to obtain trimethylol（ TMM）,followed by a polycondensation reaction with a large excess of phenol（ ≥8∶ 1） at 95 ℃ for 48 h in a near neutral environment. The N-PF obtained has a high nitrogen content（ ≥21%）,an extremely narrow molecular weight distribution（ MWD）,and a well-defined chemical structure with no reactive hydroxymethyl groups and no detectable unreacted starting materials. Since N-PF is a curing agent for phosphorus-containing epoxy resin,the flame retardant,heat resistance and electrical insulation properties of N-PF cured product were studied and compared with a generalpurpose phenolic resin.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2016年第10期18-22,共5页
Polymer Materials Science & Engineering
关键词
含氮酚醛树脂
三羟甲基三聚氰胺
缩聚反应
相对分子质量分布
固化剂
含磷环氧树脂
nitrogen-containing phenolic-formaldehyde resin
trimethylol melamine
condensation polymerization
molecular weight distribution
curing agent
phosphorus-containing epoxy resin
作者简介
通讯联系人：康富春，主要从事有机及高分子合成化学研究，E-mail：conradkfc@aliyun．com
