摘要
以改性胺1618固化剂为囊芯、脲醛树脂为壁材单体,采用界面聚合技术,成功制备了一种新型聚脲改性胺微胶囊固化剂。通过正交设计试验,考察了芯壁质量比、乳化剂种类和质量分数及搅拌速率对微胶囊包覆率、粒径大小及分布情况的影响,并确定了最佳制备工艺条件。采用马尔文激光粒度仪、扫描电镜对微胶囊粒径大小、分布情况及表面形貌进行表征,采用热重分析仪及傅里叶变换红外光谱对其化学结构进行表征,通过拉伸试验对自修复材料的断裂力学性能进行研究。结果表明,该微胶囊含有固化剂芯材,其热稳定温度为198°C,当芯壁质量比为0.7∶1、乳化剂为阿拉伯胶、乳化剂质量分数为1.5%、搅拌速率为800r/min时,所制备的微胶囊包覆率达到79.8%,平均粒径为207.5nm,呈规则的球形,分散性及表面致密性好。当基体材料中加入质量分数为1%的微胶囊后,拉伸强度提高64%,弹性模量提高287%。
A new type of poly（urea formaldehyde） microcapsules was prepared using urea formaldehyde resin as shell material and modified amine 1618 as core material by interfacial polymerization process. The effects of mass ratio of core and shell（mCore∶mShell）, the type of emulsifier, mass fraction of emulsifier and stirring speed on encapsulation rate, the particle size and distribution of microcapsules were investigated by orthogonal experiment. The particle size, distribution and surface topography of microcapsules were characterized using Malvern laser particle size analyzer and scanning electron microscopy. The compositions of microcapsules were characterized using TG DTA and Fourier transform infrared spectroscopy. The mechanical properties were evaluated using tensile testing machine. Results showed that mold curing agent of modified amine was encapsulated in the microcapsule and the decomposition temperature of the microcapsules was about 197 °C. When the mCore∶mShell was 0.7∶1, mass fraction of Arabic gum （used as emulsifier） was 1.5% and stirring speed was 800 r/min, the encapsulation rate was 79.8%, the mean diameter was 207.5 nm and the microcapsules exhibited uniform round and compact surface. The addition of microcapsules in epoxy matrix can improve its mechanical properties. When the mass fraction of microcapsules was 1%, the tensile strength and elasticity modulus of matrix were increased by 64% and 287%, respectively.
出处
《功能高分子学报》
CAS
CSCD
北大核心
2014年第1期41-46,共6页
Journal of Functional Polymers
基金
国家自然科学基金(21106022)
关键词
微胶囊
改性胺
固化剂
界面聚合法
microcapsule
modified amine
mold-curing agent
interracial polymerization process
