紫外光固化型支化聚氨酯分散剂的合成

Synthesis of UV-curable branched polyurethane dispersants

为使分散剂具有自黏合的效果以提高印花牢度,通过在聚氨酯末端分别引入颜料锚固基团和双键基团,合成了一系列紫外光固化型支化聚氨酯分散剂(BPUs)。通过FTIR、GPC、TGA对BPUs的分子结构与性能进行了表征。以BPUs制备的酞菁蓝颜料色浆的分散性能良好,粒径分布均匀且具有较低的表观黏度,颜料色浆在高温(50℃)储存5 d的粒径变化最小的在20 nm以内,在3×10^(3) r/min下离心30 min,颜料色浆的离心稳定性在92%以上。使用该颜料色浆不添加黏合剂直接印花,棉织物水洗牢度保持在3~4级,比商用分散剂提高了2级左右。

A series of UV-curable branched polyurethane dispersants(BPUs)were synthesized by introducing pigment anchoring group and double bond group at the end of the polyurethane,which made the dispersant have self-adhesive effect to improve the printing fastness.The molecular structure and properties of BPUs were characterized by FTIR,GPC and TGA.Then,BPUs were used to prepare phthalocyanine blue pigment paste samples.The pigment paste samples had good dispersion properties,uniform particle size distribution and low viscosity,and the minimum particle size change was less than 20 nm after 5 d of high temperature(50℃)storage,and the centrifugation stability was above 92% at 3000 r/min.When the paste samples were used for printing directly without adding adhesive,the washing fastness of cotton fabric was maintained at 3~4 levels,which was about 2 levels higher than that of commercial dispersant.