单组分聚氨酯改性环氧界面剂的合成及性能

Synthesis and Properties of One Component Polyurethane Modified Epoxy Interface Agent

为解决铁路桥梁混凝土基材与聚氨酯弹性体之间黏结强度低、起泡、密闭性差等问题,先利用环氧树脂、3‑巯丙基三甲氧基硅烷、异氰酸酯、聚醚二元醇分别制备聚氨酯改性环氧预聚体B、软段预聚体C,再按配合比将其与聚氨酯潜固化剂、无水乙酸丁酯、氧化铁红及其他助剂高速搅拌均匀,得到多种单组分聚氨酯改性环氧界面剂。通过试验分析主要组分对界面剂性能的影响。结果表明:掺入环氧树脂能够提高界面剂与混凝土试块的黏结强度,降低吸水率;先采用环氧树脂E‑20、3‑巯丙基三甲氧基硅烷、二苯基甲烷二异氰酸酯、聚四氢呋喃醚二元醇1000制备预聚体,再加入3%聚氨酯潜固化剂TKTY‑001所制备的界面剂表干时间5 min、吸水率0.8%,在潮湿混凝土试块上施工表面平整、无气泡,与混凝土试块黏结强度达到2.7 MPa,综合性能最优。

In order to solve the problems of low bonding strength,foaming and poor sealing between railway bridge concrete substrate and polyurethane elastomer,polyurethane modified epoxy prepolymer B and soft segment prepolymer C were prepared by using epoxy resin,3-Mercaptopropyl trimethoxysilane,isocyanate and polyether diol respectively,and then mixed with polyurethane latent curing agent,anhydrous butyl acetate,iron oxide red and other additives at high speed according to the mix proportion.A variety of one component polyurethane modified epoxy interfacial agents were obtained.The influence of main components on the properties of interfacial agent was analyzed through experiments.The results show that the addition of epoxy resin can improve the bonding strength between the interface agent and the concrete test block and reduce the water absorption.First,epoxy resin E-20,3-Mercaptopropyl trimethoxysilane,diphenylmethane diisocyanate and polytetrahydrofuran ether diol 1000 are used to prepare prepolymer,and then 3%polyurethane latent curing agent TKTY-001 is added.The surface drying time of the prepared interface agent is 5 min and the water absorption is 0.8%.The construction surface on the wet concrete test block is flat and free of bubbles.The bonding strength with the concrete test block reaches 2.7 MPa,and the comprehensive performance is the best.