原位聚合对3D打印砂浆力学性能的影响及机理  

Effects of in-situ Polymerization on Mechanical Properties of 3D Printing Mortars and Its Mechanism

作　　者：冯攀 刘钊龙 邵丽静 王伟 洪锦祥 缪昌文[1,2] FENG Pan;LIU Zhaolong;HAO Ljing;WANG Wei;HONG Jinxiang;MIAO Changwen(School of Materials Science and Engineering,Southeast University,Jiangsu Key Laboratory of Construction Materials,Nanjing 211189,China;State Key Laboratory of High Performance Civil Engineering Materials,Nanjing 210008,China;Jiangsu Sobute New Materials Co.,Ltd.,Nanjing 211103,China)

机构地区：[1]东南大学材料科学与工程学院,江苏省土木工程材料重点实验室,南京211189 [2]高性能土木工程材料国家重点实验室,南京210008 [3]江苏苏博特新材料股份有限公司,南京211103

出　　处：《硅酸盐学报》2023年第5期1093-1103,共11页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(51890904,52122802,52078126);江苏省创新支撑计划(BZ2022036)。

摘　　要：为了实现3D打印砂浆力学性能的提升,选用丙烯酰胺为单体,以原位聚合的方式在3D打印砂浆中生成聚丙烯酰胺网络,探究原位聚合对3D打印砂浆力学性能的影响,并通过Fourier变换红外光谱、扫描电子显微镜、压汞仪测试和X射线计算机断层成像等手段对其影响机理进行探究.结果表明:AM原位聚合体系可以提高3D打印砂浆的流动性,减少宏观缺陷的产生,提高打印质量.AM单体聚合后会形成有机网络与水泥水化产物相互交错连接形成的"刚?柔"复合网络结构.这种结构极大的增强了3D打印试件的抗折强度和界面粘接强度,最高可使其28 d抗折强度提高52.4%,28 d相对界面粘接强度提高78.1%.Acrylamide was selected as a monomer to generate polyacrylamide network in 3D printing mortars via in-situ polymerization,and the effect of in-situ polymerization on the mechanical properties of 3D printing mortars was investigated.The influence mechanism was analyzed by Fourier transform infrared spectroscopy,scanning electron microscopy,mercury intrusion porosimetry,and X-ray computed tomography.The results show that the in-situ polymerization of AM can enhance the fluidity of 3D printing mortars,reduce the generation of macroscopic defects,and improve the printing quality.After AM monomers are polymerized,a“rigid-flexible”composite network structure is formed,in which the organic network and the cement hydration products are intertwined.This structure greatly enhances the flexural strength and relative bonding strength of the 3D printed specimen.The 28 d flexural strength and the relative interfacial bonding strength can be increased by 52.4%and 78.1%,respectively.

关 键 词：3D打印砂浆 原位聚合 丙烯酰胺 力学性能 

分 类 号：TU528[建筑科学—建筑技术科学]