低分子量水溶性酚醛树脂的合成及表征  

Synthesis and Characterizion of Water-soluble Low-molecular-weight Phenol-formaldehyde Resol Resin

作　　者：罗翠锐[1] 翁凌[1] 吴化军 李子帙[3] 王凤春[1] 朱兴松[1] 刘立柱[1] 

机构地区：[1]哈尔滨理工大学材料科学与工程学院 [2]嘉兴市清河高力绝缘有限公司,浙江嘉兴314031 [3]哈尔滨理工大学应用科学学院,哈尔滨150040

出　　处：《绝缘材料》2010年第3期12-15,共4页Insulating Materials

摘　　要：以Ba(OH)2.8H2O为催化剂,在苯酚与甲醛摩尔比为1∶2的条件下,采用一次逐步加入甲醛的方式合成了低分子量水溶性酚醛树脂。使用13C_NMR对产物结构进行表征,通过GPC、DSC测量最终产物的分子量及分布和热行为。结果表明:在Ba2+催化作用下的羟甲基化反应中,苯酚的邻位活性更高。合成的水溶性酚醛树脂是聚合度为2～4的聚合体的混合物,这些聚合体以邻-对位和对-对位方式连接形成亚甲基桥,有大量的高邻位取代羟甲基苯酚,树脂多分散指数为1.17,分子量分布较窄,DSC谱图分别在144～168℃和186～199℃出现两个独立的放热峰,树脂通过两步反应实现最终固化。A water-soluble low-molecular-weight phenol-formaldehyde resol resin was synthesized with a molar ratio of 1：2 between the catalyst Ba（OH）2·8H2O） and a gradual addition of formalin in a one process step. The structural change of the resin was determined by 13C nuclear magnetic resonance（NMR）; Gel permeation chromatography（GPC） was used in the determination of average molar masses; and the thermal behavior of the resol solution was studied using differential scanning calorimetry（DSC）. In the study, a higher reactivity of free ortho sites toward the methylol groups of the phenolic units was observed; the product is a mixture consisting of polymers with polymerization degree from 2 to 4, in which the phenolic ring was linked via methylene in ortho-para and para-para positions. In the mixture, many phenolic rings substituted by hydroxymethyls at ortho positions were observed. The polydispersity of the resin is 1.17 with narrow molecular weight distribution. Two well-separated curing signals were observed in the exotherms of the resol resin at 144-168℃ and 186-199℃, respectively; and the resin was cured via two-step reactions.

关 键 词：酚醛树脂 分子结构 分子量分布 固化行为 

分 类 号：TM215.1[一般工业技术—材料科学与工程]