辐射交联共聚聚丙烯的超临界二氧化碳发泡行为及其性能研究  

Supercritical carbon dioxide foaming behavior and properties of radiation cross-linked polypropylene random copolymer

作　　者：王吉祥 谢放华[1] 曾虹燕[1] 杨俊杰 黄承辉 杨晨光[3] 李会[3] 吴国忠 WANG Jixiang;XIE Fanghua;ZENG Hongyan;YANG Junjie;HUANG Chenghui;YANG Chenguang;LI Hui(School of Chemical Engineering, Xiangtan University, Xiangtan 411105, China;Zhejiang Sinco-polymer Material R&D Centre, Jiashan 314100, China;Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China)

机构地区：[1]湘潭大学化工学院,湘潭411105 [2]浙江中科辐射高分子材料研发中心,嘉善314100 [3]中国科学院上海应用物理研究所,上海201800

出　　处：《辐射研究与辐射工艺学报》2019年第5期11-19,共9页Journal of Radiation Research and Radiation Processing

基　　金：国防基础科研核基础科学挑战计划（TZ2018004）资助~~

摘　　要：用三烯丙基异氰脲酸酯(TAIC)作为交联剂与无规共聚聚丙烯(PPR)共混制备片材,用γ射线在空气环境下对片材样品进行辐照,并利用超临界二氧化碳对片材进行间歇发泡.通过对样品结晶行为、凝胶含量和泡孔形貌进行分析,研究了交联剂TAIC和不同吸收剂量对PPR的结构和发泡性能的影响.结果表明:交联剂TAIC的添加在熔融共混时能促进PPR产生轻微交联,辐照后PPR/TAIC(质量分数2%)的交联程度增加,同时也发生氧化裂解,并且氧化裂解程度随吸收剂量增加而增大;PPR中主要存在α晶型和γ晶型,发生交联后能形成更多的γ晶型,γ晶型的存在能触发产生更多的成核位点,形成良好的微孔结构.对于本研究中的PPR/TAIC(质量分数2%)片材,最佳吸收剂量为25 kGy,此时泡孔孔径达到最小约41 μm,泡孔密度达到1.5×10^10 cm^-3,发泡样品断裂伸长率达到230%.该聚丙烯样品在释压为20 MPa条件下的scCO2适宜发泡温度窗口可达10℃左右.Polypropylene random copolymer (PPR) was mixed with triallyl isocyanurate (TAIC) and pressed into a sheet. PPR sheets were irradiated by γ-rays and then foamed by supercritical carbon dioxide. The effects of TAIC and absorbed dose on the structure and foaming ability of PPR were evaluated by the gel fraction test and by determining the crystallization behavior and foam cellular structure. It was found that PPR was cross-linked by TAIC. After irradiation, the degree of crosslinking in PPR/TAIC(2%) increased, and the degree of oxidative degradation increased with absorbed dose.α and γ crystals were observed in PPR, and more γ crystals were found after crosslinking. The γ crystals induced more nucleation sites and formed better foams. The optimal absorbed dose obtained in this study was 25 kGy. The cell diameter decreased to 41 μm and the cell density increased to 1.5 × 10^10 cm^-3. The tensile strain of the sample reached 230%, and the suitable foaming temperature window reached 10 ℃ at the release pressure of 20 MPa.

关 键 词：无规共聚聚丙烯 辐射交联 γ晶型 结晶度 超临界二氧化碳发泡 

分 类 号：TL13[核科学技术—核能科学]