丙烯腈/4-乙烯基吡啶辐射溶液共聚合  

Radiation-induced solution copolymerization of acrylonitrile and 4-vinylpyridine

作　　者：孙锐[1] 王雨松 姜志文 舒晶晶 汪谟贞[1] 葛学武[1] SUN Rui;WANG Yusong;JIANG Zhiwen;SHU Jingjing;WANG Mozhen;GE Xuewu(CAS Key Laboratory of Soft Matter Chemistry,Department of Polymer Science and Engineering,University of Science and Technology of China,Hefei 230026,China;Hefei National Laboratory for Physical Sciences at the Microscale,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学院软物质化学重点实验室,中国科学技术大学高分子科学与工程系,合肥230026 [2]中国科学技术大学合肥微尺度物质科学国家研究中心,合肥230026

出　　处：《辐射研究与辐射工艺学报》2022年第1期27-38,共12页Journal of Radiation Research and Radiation Processing

摘　　要：丙烯腈(AN)与亲水性单体的共聚是制备亲水性聚丙烯腈(PAN)功能材料的有效方式之一。本研究以AN与4-乙烯基吡啶(4-VP)的二甲亚砜(DMSO)溶液为研究对象,开展了γ射线辐射溶液共聚合制备AN/4-VP二元共聚物的研究,并对所合成的二元共聚物的化学结构、相对分子量、热性能和亲水性进行了表征分析。研究结果表明:γ射线辐照可以在室温下顺利引发AN和4-VP在DMSO中的共聚反应。吸收剂量在25 kGy时,单体转化率即达到90%以上,但所得共聚物相对分子量与剂量率相关。在30 kGy吸收剂量下,采用较低的剂量率(如11 Gy/min)辐照时,可以直接得到黏度为250 Pa·s的P(AN-co-4-VP)二元无规共聚物溶液,所合成的共聚物重均相对分子量约13万,两种单体结构单元组成与投料比一致;当剂量率超过20 Gy/min,所合成的共聚物相对分子量反而下降。当4-VP与AN的相对物质的量比较低(2%)时,辐射溶液聚合合成的P(AN-co-4-VP)二元无规共聚物热性能基本与PAN均聚物一致,并且4-VP并不参与-C≡N侧基的成环或交联反应。但P(AN-co-4-VP)二元无规共聚物的水接触角随着4-VP含量增加而逐渐减小,说明4-VP的引入可以提高PAN的亲水性。本文不仅为聚丙烯腈亲水改性提供了新思路,而且证明采用辐射溶液聚合方式可以直接得到高质量分数(>20%)的丙烯腈均聚物或共聚物的DMSO溶液,拓展了辐射技术在丙烯腈溶液聚合领域中的应用。The copolymerization of acrylonitrile(AN)with a hydrophilic monomer is an effective way to prepare hydrophilic polyacrylonitrile(PAN)-based functional materials.In this study,γ-ray radiation-induced copolymerization of AN and 4-vinylpyridine(4-VP)in dimethylsulfoxide(DMSO)was carried out.The chemical structure,molecular weight,thermal properties,and hydrophilicity of the synthesized copolymers were characterized.Theγ-ray radiation could initiate the copolymerization of AN and 4-VP in DMSO at room temperature(0~35℃).The monomer conversion reached above 90%at the absorbed dose of 25 kGy,but the molecular weight of the copolymer depended on the dose rate.When the absorbed dose was 30 kGy,a P(AN-co-4-VP)random copolymer solution with a viscosity of 250 Pa·s was obtained directly after the monomer solution was irradiated byγ-rays at a lower dose rate of 11 Gy/min.The P(AN-co-4-VP)copolymer had a weight-average molecular weight of 1.34×10^(5),and the relative content of AN and 4-VP units in the copolymer chains was identical to the feed ratio of AN and the 4-VP comonomer.When the dose rate exceeded 20 Gy/min,molecular weight of the synthesized copolymer decreased remarkably.Thermal properties of the P(AN-co-4-VP)random copolymer with the relative molar ratio of 4-VP to AN of 2%were generally the same as those of the PAN homopolymer.The 4-VP units in the polymer chains did not participate in the ring formation or crosslinking reaction of the side‒C≡N groups.However,the water contact angle of the P(AN-co-4-VP)random copolymer decreased gradually with increase in 4-VP content,indicating that the introduction of 4-VP units can improve the hydrophilicity of the copolymers.This study provides a new idea for the hydrophilic modification of PAN as well as proves that DMSO solutions with a high mass fraction(>20%)of the homo-or copolymer of AN can be obtained directly via radiation-induced solution polymerization,thus expanding the potential applications of the high-energy radiation technique in the field of solution

关 键 词：辐射溶液聚合 Γ射线 丙烯腈 4-乙烯基吡啶 亲水性聚丙烯腈 

分 类 号：TL13[核科学技术—核能科学]