混凝土用聚甲醛纤维的耐碱性能研究  

Study on Alkali Resistance of Polyacetal Fiber for Concrete

作　　者：王天琪 杨鼎宜[2,3] 谈永泉 范志勇 WANG Tian-qi;YANG Ding-yi;TAN Yong-quan;FAN Zhi-yong

机构地区：[1]苏州混凝土水泥制品研究院检测中心有限公司,215000 [2]扬州大学建筑科学与工程学院,225127 [3]扬州大学绿色建筑材料研究所,225127

出　　处：《混凝土与水泥制品》2019年第12期52-55,共4页China Concrete and Cement Products

基　　金：国家重点研发计划项目(2018YFD1101002-05、2016YFB0303104);国家自然科学基金项目(51578479、51708483)

摘　　要：根据不同的水泥碱度设计了6种pH值的NaOH溶液对聚甲醛纤维(POM纤维)进行加速老化试验,同时用基准水泥上层清液做POM纤维的常温浸泡试验,通过测试浸泡前后纤维的直径和强度探究了POM纤维的耐碱性能,并对不同浸泡环境、不同浸泡时间下的纤维进行了微观形貌分析和红外测试,找出了不同浸泡条件下的时间对应关系。试验结果表明,POM纤维在两种浸泡环境下,随着时间的延长,直径逐渐增加,强度减小,POM纤维在pH=14的NaOH溶液中加温浸泡6 h相当于在基准水泥上层清液中常温浸泡28 d。POM纤维的腐蚀是一个逐层腐蚀的过程,碱溶液最先腐蚀纤维表面和内部杂质,其次腐蚀结构缺陷部分,发生C-O-C和CH2基团位移,导致纤维力学性能下降,但POM纤维整体结构骨架并没有受到严重腐蚀,具有较好的耐碱性能。6 kinds of NaOH solution with pH according to different cement alkalinity were designed to accelerate the aging test of POM fiber,and the benchmark cement supernatant was used to make POM fiber at room temperature immersion test.The alkali resistance of POM fiber was investigated by testing the diameter and strength of the fibers before and after soaking.Microscopic morphology analysis and infrared testing were performed on the fibers under different soaking times in different soaking environments to find out the time correspondence under different soaking conditions.The results show that the POM fiber gradually increases in diameter and strength after prolonging in two kinds of immersion environments.POM fiber is immersed in NaOH solution with pH=14 for 6 h,which is equivalent to the reference cement supernatant at room temperature for 28 d.The corrosion of POM fiber is a layer-by-layer corrosion process,the alkali solution first corrodes the fiber surface and internal impurities,and secondly corrodes the structural defects,and the C-O-C and CH2 groups are displaced,resulting in a decrease in fiber mechanical properties.However,the overall structural skeleton of the POM fiber is not seriously corroded and has good alkali resistance.

关 键 词：混凝土 聚甲醛纤维 耐碱性能 对应关系 微观形貌 红外测试 

分 类 号：TU528.041[建筑科学—建筑技术科学]