一锅法制备聚己内酯多元醇改性丙烯酸分散体及其应用研究

Preparation of Polycaprolactone Polyol-modified Acrylic Dispersions by One-pot Method and Application Research

采用一锅法,先以三羟甲基丙烷(TMP)作为扩链剂引发ε-己内酯开环聚合制得聚己内酯多元醇(PCLT),再以PCLT为原料制得柔韧性优异的低羟基含量丙烯酸分散体(LHAD)。通过凝胶渗透色谱、傅立叶变换红外光谱和核磁共振氢谱表征PCLT,探究PCLT改性LHAD制备时的反应温度、n(己内酯)∶n(TMP)、溶剂种类,PCLT含量,LHAD理论玻璃化转变温度对PCLT和LHAD性能的影响。结果表明:反应温度为145℃、n(己内酯)∶n(TMP)为12.17、乙酸丁酯和乙二醇丁醚等质量混合作为釜底溶剂体系,PCLT含量9.4%,LHAD理论玻璃化转变温度为41.85℃,制得LHAD粒径较小、黏度适中、固含量高且热贮存稳定性较好。将LHAD搭配水性多异氰酸酯固化剂(AQUAPU-298)制备水性双组分聚氨酯涂料,涂层固化后硬度为F,同时具有优异的柔韧性及光泽。

Polycaprolactone polyol(PCLT)was produced by ring-opening polymerisation ofε-caprolactone using trimethylolpropane(TMP)as a chain extender in a one-pot method,and then low hydroxyl-content acrylic dispersions(LHAD)with excellent flexibility were produced from PCLT.The PCLT was characterised by gel permeation chromatography,fourier transform infrared(FT-IR)spectroscopy and nuclear magnetic resonance(1H NMR)hydrogen spectroscopy,and the effects of reaction temperature,n(caprolactone)∶n(TMP),solvent type,PCLT content,and the theoretical glass transition temperature of LHAD on the properties of PCLT and LHAD were investigated.The results showed that the reaction temperature of 145℃,n(caprolactone)∶n(TMP)of 12.17,the mass mixture of butyl acetate and ethylene glycol butyl ether as the polymerisation solvent system,the content of PCLT of 9.4%,and the theoretical glass transition temperature of LHAD of 41.85℃resulted in the production of LHAD with smaller particle size,moderate viscosity,high solid content,and better thermal storage stability.The waterborne two-component polyurethane coatings was prepared by combining LHAD with waterborne polyisocyanate curing agent(AQUAPU-298),and the hardness of the coating was F after curing,and the coating also had excellent flexibility and gloss.