摘要
以耐高温型聚酰亚胺为基体,微米碳化硼(B_4C)为热中子吸收剂,采用粉体表面改性及超声湿混-热亚胺化成膜工艺成功制备了一系列B_4CP/PI聚酰亚胺复合薄膜,重点探讨了不同B_4C含量条件下复合薄膜的耐热性能和力学性能以及不同B_4C含量、不同复合薄膜厚度条件下复合材料的热中子屏蔽性能。研究表明:采用上述工艺,B_4C功能粒子在聚酰亚胺基体中可均匀分散;B_4CP/PI复合薄膜的耐热性随B_4C含量的增加显著提高,力学性能则呈相反趋势;所制备的B_4CP/PI复合薄膜表现出优异的热中子屏蔽性能,中子透射率I/I0随复合薄膜厚度增加及B_4C含量增加呈指数变化规律。据此,可通过材料结构设计,满足不同领域对该类耐高温中子防护材料的应用需求。
B_4CP/PI polyimide composite films with different powder contents and thicknesses were prepared by particle surface modification and wet mixing machinery-thermal imidization method,using high temperature polyimide as matrix and micro-sized boron carbide(B_4C)as thermal neutron absorption material.The thermal neutron radiation shielding property,thermal stability and mechanical property of B_4CP/PI polyimide composite films were mainly discussed in this paper.It is shown that the micro-sized B_4C functional particles can be well dispersed in PMDA-ODA polyimide matrix,and the thermal stability of B_4CP/PI polyimide composite films are significantly improved with the increase of B_4C content.However,the mechanical properties of the composite films present the opposite trend;meanwhile,the B_4CP/PI polyimide composite films exhibit excellent thermal neutron radiation shielding properties,and the neutron permeability I/I0 presents exponential relationship with the increasing thickness of composite and B_4C filler particle content.Therefore,through structural design of the materials,the applications requirements in different fields for materials with high temperature resistant and thermal neutron radiation shielding properties can be met.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2018年第3期48-54,共7页
Journal of Materials Engineering
基金
国家863计划基金项目(2015AA034004)
中国工程物理研究院双百人才工程基金项目(ZX20150402)
四川省科技支撑计划基金项目(2015GZ0068)
国家青年科学基金(21404095)
关键词
聚酰亚胺
碳化硼
热中子辐照屏蔽
热性能
力学性能
polyimide
boron carbide
thermal neutron radiation shielding
thermal stability
mechanical property
