摘要： 采用自乳化聚氨酯水分散体的制备方法,分别制备了含蓖麻油基和巯基的聚氨酯水分散体。将两者按一定比例复合,加入水性光引发剂,在紫外光照射下,通过水性光引发剂引发涂层中的双键及巯基进行巯基-烯点击反应,制得交联聚氨酯涂膜。采用核磁共振氢谱、红外光谱、差示扫描量热仪、热重分析等手段对水分散体及光固化涂膜的结构和性能进行了分析表征。结果表明:巯基和蓖麻油结构中的碳碳双键成功地引入到了水性聚氨酯链段中;在紫外光辐照下,巯基和不饱和双键间进行了加成反应;UV固化膜具有良好的机械性能和热稳定性:凝胶量为96.67%、胶膜吸水率为13.0%、耐冲击性大于50 cm、硬度为5H、耐溶剂(甲乙酮)拭擦次数为734次、失质量50%时的温度为375℃。
关键词:
紫外光固化,
水性聚氨酯分散体,
巯基-烯复合反应,
蓖麻油
Abstract: Waterborne polyurethane containing castor oil( CAPU) and waterborne polyurethane containing multifunctional thiol (SHPU) were prepared via self-emulsification process of WPU, respectively,which were-blended with addition of aqueous photo-initiator in certain proportions, then crosslinked to form polyurethane coatings through thiol-ene couple reaction between the double bond and thiol under UV irradiation. The structure and properties of the title coatings were characterized by 1 H-NMR, FT-IN,DSC and TG. The results indicated that thiol and the double bond in castor oil were integrated into polyure thane main chain and thiol-ene addition reaction was proceeded. The UV-cured films showed good me-chanical properties and thermal stability with gel content 96. 67%, solvent-resistance( methyl ethyl ketone) 734 times, pencil hardness 5H, water absorption 13.0%, impact strength 50 cm and 50% mass loss at 37.5℃,respectively.
Key words:
UV-curable,
aqueous polyurethane dispersions,
thiol-ene couple reaction,
castor oil
付长清, 陈 樟, 乔永洛, 陈义旺, 申 亮. 蓖麻油改性巯基-烯UV固化水性聚氨酯分散体的制备[J]. 涂料工业, 2012, 42(10): 37-40.
Fu Changqing, Chen Zhang, Qiao Yongluo, Chen Yiwang, Shen Liang. Preparation of Castor Oil Modified Thiol-Ene UV-Curable Waterborne Polyurethane Dispersions[J]. Paint & Coatings Industry, 2012, 42(10): 37-40.