咔唑基团功能化全同聚丙烯抗紫外老化性能研究  

UV Aging of Isotactic Polypropylene Functionalized with Carbazole Groups

作　　者：马松峰 刘超[1] 孙晓伟 高欢 王菲 潘莉 李悦生[1] Song-feng Ma;Chao Liu;Xiao-wei Sun;Huan Gao;FeiWang;Li Pan;Yue-sheng Li(School of Materials Science and Engineering,Tianjin University,Tianjin 300350)

机构地区：[1]天津大学材料科学与工程学院,天津300350

出　　处：《高分子学报》2022年第12期1523-1533,共11页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21574097)资助项目.

摘　　要：通过丙烯和含咔唑基团的α-烯烃的直接共聚,向全同聚丙烯中引入了具有可吸收紫外光的咔唑基团.咔唑基团具有吸收紫外光及365 nm紫外光下具有明显的蓝紫色发光特性,可能赋予材料抗光氧老化性能.利用核磁共振波谱和红外等对丙烯/11-咔唑-1-十一碳烯(P-C)共聚物结构进行了明确表征,共聚物中咔唑基团的含量分别为0.45 mol%~1.67 mol%.对不同咔唑基团含量的P-C样品进行了紫外老化处理,并对其抗紫外老化性能进行了研究.在相同老化条件下,当丙烯均聚物(PP)样品表面出现大而深的裂纹时,P-C样品表面没有裂纹或仅出现了细微的裂纹.与iPP样品相比,老化后的P-C样品拉伸性能、热性能等在老化过程中得到了良好保持,降解反应受到明显抑制.综上所述,含有共轭结构的咔唑基团的引入能有效增强聚丙烯的抗紫外老化性能.Carbazole group functionalized isotactic polypropylene(P-C)samples were prepared via direct copolymerization of propylene andα-olefin bearing terminal carbazole group.The carbazole group could absorb ultraviolet light and exibibit blue-purple luminescence under 365 nm ultraviolet light,which may endows the material with anti-photooxygen aging property.13C-NMR data showed that the propylene/11-carbazole-1-undecene copolymer(P-Cs)have high tacticity.In order to maintain the excellent mechanical properties of isotactic polypropylene,the incorporation of comonomer was controlled at 0.45 mol%-1.67 mol%.The P-C samples with different carbazole group contents were studied via UV aging and the UV-oxidative stability tests.After the same aging time,when large and deep cracks were observed on the surface of the iPP sample,only the P-C1 sample with the lowest carbazole group content showed small cracks on the surface,while the P-C2 and P-C3 samples with higher content of carbazole groups had no cracks.Tensile tests revealed that losses in tensile properties of the P-C samples were far less compared to that of the pure iPP sample.At 120 h,the mechanical properties of the iPP samples were completely lost.Under the same conditions,the tensile strength of the P-C1 samples remained above 98%,and the tensile strengths of the P-C2 and P-C3 samples were significantly improved.The DSC data showed that the melting temperature(Tm)of the iPP samples decreased by 7℃after UV irradiation,while the Tm of the samples in the P-C group decreased by at most 2℃.which indicated that the introduction of carbazole groups could stabilize the thermal properties of the samples under UV irradiation.GPC test results showed that the thermal properties and molecular weghts of polypropylenes with carbazole group were well maintained after the UV aging process,and that the degradation reaction has been significantly inhibited.In conclusion,the introduction of carbazole groups could effectively enhance the UV-oxidative stability of polypropylene.

关 键 词：全同聚丙烯 咔唑基团 配位聚合 抗紫外老化 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]