建筑增强用聚丙烯腈纤维的耐碱性研究  

Study on alkali resistance of polyacrylonitrile fibers for building reinforcement

作　　者：张磊 徐静 邹黎明 陈烨 柯福佑 ZHANG Lei;XU Jing;ZOU Liming;CHEN Ye;KE Fuyou(The Key Laboratory of High-Performance Fibers and Products of Ministry of Education,College of Materials Science and Engineering,Donghua University,Shanghai 201620)

机构地区：[1]东华大学材料科学与工程学院高性能纤维及制品教育部重点实验室,上海201620

出　　处：《合成纤维工业》2020年第5期11-15,共5页China Synthetic Fiber Industry

基　　金：国家重点研发计划项目(2016YFB0303200)。

摘　　要：模拟混凝土配置时的高温碱性环境,将建筑增强用聚丙烯腈(PAN)纤维浸泡在(80±2)℃、1 mol/L的氢氧化钠溶液中进行碱老化,浸泡时间6 h,研究了碱老化前后纤维的结构与力学性能的变化以及纤维的耐碱性,并与聚对苯二甲酸乙二醇酯(PET)增强纤维和聚丙烯(PP)增强纤维进行对比。结果表明:碱老化6 h后,建筑增强用PAN纤维在3348 cm-1和1570 cm-1出现羧酸盐特征基团的新吸收峰,表面沟槽有所加深,结晶度和晶区取向度分别下降4.4%和1.7%,拉伸强度和初始模量分别为996 MPa和14.9 GPa,分别下降21.6%和13.4%,极限拉力保持率为91.0%;碱老化6 h后,PET增强纤维和PP增强纤维的极限拉力保持率分别为77.0%和99.6%;建筑增强用PAN纤维的耐碱性介于PP增强纤维和PET增强纤维之间,但其在碱性环境中保持突出的模量优势,可以更好地提高混凝土的耐受力。Polyacrylonitrile(PAN)fibers for building reinforcement were exposed to alkali aging by immersing in(80±2)℃,1 mol/L sodium hydroxide solution for 6 h.The structure and mechanical properties of the fibers before and after alkali aging and the alkali resistance of the fibers were studied and compared with those of polyethylene terephthalate(PET)reinforced fiber and polypropylene(PP)reinforced fiber.The results showed that the new absorption peaks of carboxylate characteristic groups appeared at 3348 cm-1 and 1570 cm-1 of PAN fiber for building reinforcement after alkali aging for 6 h,the surface grooves were deepened,the crystallinity and crystalline orientation degree of the fibers decreased by 4.4%and 1.7%,respectively,the tensile strength and initial modulus were 996 MPa and 14.9 GPa with a decrease of 21.6%and 13.4%,respectively,and the ultimate tension retention was 91.0%;the ultimate tensile retention of PET reinforced fiber and PP reinforced fiber was 77.0%and 99.6%,respectively,after alkali aging for 6 h;and the alkali resistance of PAN fiber for building reinforcement was between that of PP reinforced fiber and PET reinforced fiber,but its outstanding modulus can effectively improve the concrete resistance in alkaline environment.

关 键 词：聚丙烯腈纤维 增强纤维 纤维增强混凝土 极限拉力保持率 耐碱性 

分 类 号：TQ342.31[化学工程—化纤工业]