电子辐照LDPE/MWCNTs复合材料的熔融与结晶行为  

Melting and crystallization behaviours of the electrons irradiated LDPE/MWCNTs composites

作　　者：马国亮[1] 李兴冀[1] 杨剑群[1] 刘超铭[1] 田丰[2] 侯春风[1] 

机构地区：[1]哈尔滨工业大学,哈尔滨150001 [2]中国科学院上海应用物理研究所,上海201204

出　　处：《物理学报》2016年第20期242-254,共13页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11305249;51503053);中国博士后科学基金(批准号:2014M560256)资助的课题~~

摘　　要：电子是空间带电粒子辐射环境的重要组成部分,会对航天用微电子器件产生严重的辐射损伤.因此,对电子器件进行有效的辐射防护至关重要,迫切需要一种轻质、高性能和低成本的辐射防护材料.富氢的聚乙烯(PE)/碳纳米管(CNTs)复合材料是富有前途的空间辐射防护材料.针对PE/CNT复合材料空间辐射防护应用的需要,系统研究低密度聚乙烯/多壁碳纳米管(LDPE/MWCNTs)复合材料电子辐照LDPE/MWCNTs的熔融与结晶行为,具有重要的学术价值与工程实际意义.本文利用差热扫描量热仪(DSC)和同步辐射X射线小角散射(SAXS)及广角衍射(WAXD),针对110 keV低能电子作用下LDPE/MWCNTs复合材料的熔融与结晶行为进行研究.结果表明,MWCNTs的添加,可使LDPE/MWCNTs复合材料在加热过程中的起始融化温度升高,而终止融化温度降低,并使冷却过程中的起始结晶温度提高,而终止结晶温度降低,结晶度增加.在融化过程中,MWCNTs可阻碍LDPE基体非晶区及晶区分子链运动,抑制LDPE基体的初始融化,在开始融化后促进融化过程;在结晶过程中,MWCNTs促进LDPE基体晶体的形成,并抑制晶体长大.110 ke V电子辐照可抑制LDPE基体的非晶区膨胀,延缓LDPE基体中片晶的初始融化;结晶过程中,110 keV电子辐照抑制LDPE基体的非晶区收缩,并抑制晶体长大.Electrons are an important constituent part of radiation space of charged particles and could damage microelectronic devices. Therefore, effective radiation protection is very important for the electronic device. So, a radiation protecting material with lightweight, high performance and low cost is urgently needed. Polyethylene（PE） with high hydrogen content /carbon nanotube（CNT） composite as a space shielding material is very promising for spacecraft application in the future. In order to meet the requirement of space applications for PE/CNT composite, it is of important academic value and practical significance to explore melting and crystallization behaviors of LDPE/MWCNT composites. In this paper, melting and crystallization behaviours of the irradiated LDPE/MWCNT composites irradiated by 110 keV electrons are studied by differential scanning calorimetry（DSC）, synchrotron radiation X-ray small angle scattering（SAXS）and wide angle diffraction（WAXD）. Experimental results show that the irradiation by 110 keV electrons does not affect the thermal characteristics of the LDPE, but can enhance the initial melting temperature and the melting-terminating temperature of LDPE/2% MWCNT composites during melting. Also, the radiation by 110 ke V electrons could reduce the initial crystallization temperature and the crystallization-terminating temperature during crystallization. MWCNTs could enhance the initial melting temperature and reduce the melting-terminating temperature of LDPE/2% MWCNT composites during melting. Moreover, MWCNTs could enhance the initial crystallization temperature and crystallinity,and reduce the crystallization-terminating temperature during crystallization. SAXS and WAXD analyses show that with increasing the temperature, long periods of the irradiated/unirradiated LDPE increase during melting. Compared with that of the unirradiated LDPE, at a given temperature, long period of the irradiated LDPE is small. During crystallization, with reducing the temperature, long period of t

关 键 词：纳米复合材料 电子辐照 辐照效应 热稳定性 

分 类 号：TB33[一般工业技术—材料科学与工程]