灭菌剂量下γ射线辐照对环烯烃共聚物的影响及机理研究  

Effect and mechanism ofγ-ray irradiation on cyclic olefin copolymer in the sterilization dose range

作　　者：张帆 季珎琰 沈蓉芳 邢哲[1] 吴国忠[1,3] ZHANG Fan;JI Zhenyan;SHEN Rongfang;XING Zhe;WU Guozhong(Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China;University of Chinese Academy of Sciences,Beijing 100049,China;Shanghai Tech University,Shanghai 201210,China)

机构地区：[1]中国科学院上海应用物理研究所,上海201800 [2]中国科学院大学,北京100049 [3]上海科技大学,上海201210

出　　处：《核技术》2022年第3期41-48,共8页Nuclear Techniques

基　　金：国家自然科学基金(No.22176194)资助。

摘　　要：由乙烯和降冰片烯共聚合成的环烯烃共聚物(Cyclic Olefin Copolymer,COC)具有良好的透光性、水蒸气阻隔性,以及生物相容性,适用于医疗器械和药物包装领域。这类COC医疗用品通常采用辐照灭菌来确保生物安全性,然而辐射过程会使分子链断裂产生自由基,不可避免地会发生辐射裂解、氧化、变色等现象。因此,探究电离辐射引发的自由基反应导致的COC性能变化对COC医疗用品的辐照灭菌应用具有重要意义。为了研究辐照灭菌剂量下COC的辐射效应,考察了剂量范围内γ射线对COC的化学结构、自由基信号、玻璃化转变温度、热稳定性、分子量分布、表面性质以及熔融指数的影响。结果显示:在空气中COC经辐照产生的自由基浓度随着吸收剂量增大线性增加;随着吸收剂量的增大,包括羰基、羟基类化合物等辐射氧化产物的平均分子量减小,辐射降解占优势;同时COC表面亲水性增强,熔融指数增加。辐射导致的分子链断裂以及自由基的氧化反应是COC降解的主要原因。[Background]Cyclic olefin copolymer(COC),synthesized by catalytic copolymerization of ethylene and norbornene,can be applied in medical devices and drug packaging,owing to its many outstanding properties such as good light transmittance,water vapor barrier and biocompatibility.When this type of medical devices or drug package is sterilized by high energy irradiation,COC will inevitably undergo changes such as radiation scission,oxidation,discoloration and so on.It is of great significance to explain the performance change of COC from the free radical reaction initiated by ionization radiation for the radiation sterilization application of COC medical supplies.[Purpose]This study aims to investigate radiation effect of COC in the dose range of radiation sterilization.[Methods]Effects ofγ-rays on chemical structure,free radical,glass transition temperature,thermal stability,molecular weight distribution,surface properties and melt index of the irradiated COC with the sterilization dose were investigated by Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),ultraviolet-visible absorption spectroscopy(UV-vas),electron spin resonance spectroscopy(ESRS),differential scanning calorimetry(DSC),thermogravimetric analysis(TGA),gel permeation chromatography(GPC),water contact angle(WCA)and melt mass-flow rate measurement.[Results]The concentration of free radicals produced by COC irradiation in air increases linearly with the increase of absorbed dose.With the increase of absorbed dose,radiation degradation is dominant,hence the average molecular weight of the radiation oxidation products include carbonyl and hydroxyl compounds decreases,and the surface hydrophilicity is enhanced whilst the melt index is increased.[Conclusions]The molecular chain breakage caused by radiation and the reaction between free radicals and oxygen are the main causes of COC degradation.

关 键 词：γ 射线辐照 环烯烃共聚物 辐射降解 

分 类 号：TL99[核科学技术—核技术及应用]