悬浮聚合法制备聚酰亚胺粉体及其表征

以均苯四甲酸酐、甲醇和氯化亚砜为主要原料,合成了对位均苯二甲酯二酰氯(p-PMDC),再以 p-PM-DC 和对苯二胺为单体,十二烷基硫酸钠为分散剂,采用悬浮聚合热亚胺化法制备了聚酰亚胺粉体。考察了反应温度、反应物浓度和搅拌速率对粉体粒径分布和形态的影响。并采用~1H NMR、SEM、FT-IR、激光粒径分析仪等对产物进行了表征。结果表明,在反应温度25℃和反应物浓度50 mmol/L 以及搅拌速率800 r/min 条件下,粉体产物的形貌为不规则形,平均粒径3.464μm,大部分粒子分布在1～10μm,聚酰亚胺粉体表现出良好的热稳定性。

PREPARATION AND CHARACTERIZATION OF POLYIMIDE POWDER BY SUSPENSION POLYMERIZATION METHOD

The monomer of 2,5-bis(methoxycarbonyl)terephthaloyl chloride(p-PMDC)was synthe- sized from pyromellitic dianhydride,methanol and thionyl chloride as primary raw materials.The poly (amide methyl ester)s powder was prepared by suspension-thermal imidization method,with p-PMDC and p-phenylone diamine as monomers with the addition of dispersant.The effects of reaction temper- ature,reactants concentration and stirring speed on the average particle size and the shape of the poly- mers were studied systematically.The product was characterized by ~1H NMR,SEM,FT-IR,laser size analysis(LSA),etc.The optimum conditions were obtained as follows:reaction temperature 25 ℃,reactants concentration 50 mmol/L and stirring speed 800 r/min.Under these conditions,the out- of-shape polymer particles ranging from 1 μm to 10 μm with an average particle size of 3.464μm were obtained.The polyimide powders showed good thermal stability.