硫醇点击化修饰聚醋酸乙烯酯基核壳乳液及其快速成膜性能  

Research on Thioalcohol-click Modification of PVAc-based Core/shell Emulsion and Its Rapid Film Forming Performance

作　　者：范晓慧 聂金秋 李欢欢 李志国[1] FAN Xiaohui;NIE Jinqiu;LI Huanhuan;LI Zhiguo(Material Science and Engineering College,Northeast Forestry University,Harbin 150040,China)

机构地区：[1]东北林业大学材料科学与工程学院,哈尔滨150040

出　　处：《涂料工业》2025年第1期15-23,30,共10页Paint & Coatings Industry

基　　金：国家自然科学基金(32171695)。

摘　　要：针对传统水性涂料成膜速度慢、涂装效率低的问题,通过硫醇-烯点击反应在聚醋酸乙烯酯(PVAc)基核壳乳胶粒表面接枝多官能度硫醇(TMPMP),并采用预乳化法在乳胶粒合成后期加入双键活性单体,制备了PVAc基光固化复合乳液。系统考察了复合乳液的稳定性、光固化特性、力学性能以及漆膜性能。结果表明:所制备的PVAc基核壳乳胶粒粒径在200 nm左右,表面修饰的巯基官能团能够与双键活性单体在紫外光照射下发生硫醇-烯点击反应从而实现快速成膜固化;复合乳液稳定性优良,储存期可达60 d以上。将复合乳液应用于木材光固化涂饰时,最快可在9 s内实现固化;通过调控硫醇与活性单体的比例可改善漆膜性能,当活性单体(TMPTA)用量为400%时,乳胶膜的力学性能最优,拉伸强度达到6.17 MPa,断裂伸长率为1.79%;同时,木器涂料漆膜的硬度、光泽和粗糙度分别为4H、10.8和2.34μm。硫醇-烯点击修饰的PVAc基光固化复合乳液可实现快速成膜固化,进而显著提高涂装效率,在水性木器涂料的应用中具有广阔的应用前景。Focusing on the issue of slow film formation and low coating efficiency of conventional waterborne coatings,thioalcohol-modified polyvinyl acetate(PVAc)-based emulsion was fabricated by grafting multifunctional thiols(TMPMP)on the surface of PVAc-based core-shell latex through the thiol-ene click reaction.After that,the fast UV-curable composite emulsion was prepared in one-pot method through adding pre-emulsified active monomer containing double bonds at the late stage of latex formation.The stability,photocuring characteristic,mechanical property and paint film performance of the composite emulsion were systematically investigated.The results showed that the particle size of PVAc-based core-shell latex was about 200 nm.Thioalcohol groups modified on the surface of the latex particles were able to react with reactive monomers in a thiol-ene click reaction under UV light irradiation for fast film forming and curing.The composite emulsion exhibited excellent stability which could be stored for more than 60 days.Appling to wood coatings,UV curing could be achieved in as fast as 9 s.Meanwhile,the performance of paint film could be improved by adjusting the ratio of thioalcohol to active monomer.When the dosage of active monomer(TMPTA)was 400%,the mechanical performance of light-cured latex film was obtained with the tensile strength of 6.17 MPa and elongation at break of 1.79%.In addition,the hardness,gloss and roughness of the wood coating film could be reached to 4H,10.8°and 2.34μm,respectively.The thioalcohol-modified PVAc-based photocurable composite emulsion could achieve rapid film curing,which in turn significantly improved the coating efficiency and demonstrated a broad application prospect in the waterborne wood coatings.

关 键 词：水性木器涂料 核壳结构 聚醋酸乙烯酯 硫醇-烯点击反应 紫外光固化 

分 类 号：TQ637.81[化学工程—精细化工]