Synthesis and Properties of Organofluorine and Silicon Modified Waterborne Polyurethane Emulsions
Wang Hezhi1，2， Hou Caiying1，2， Ma Guozhang1，2， Wang Shaohui1，2，Ji Xuan2
1. College of Chemistry and Chemical Engineering， Taiyuan University of Technology， Taiyuan 030024， China；
2. Shanxi Key Laboratory for Functional Polymers of Coatings， Shanxi Research Institute of Applied Chemistry， Taiyuan 030027， China
Abstract: A secondary amine-terminated fluorocarbon compound (DFMA-IPDA) was synthesized via Michael addition reaction between dodecafluoroheptyl methacrylate (DFMA) and isophorone diamine (IPDA). The compounds was used as chain extender and/or hydroxyethoxypropyl-terminated polydimethylsiloxane (PDMS) was used as diol to polycondensation with isophorone diisocyanate (IPDI), polypropylene glycol (PPG) and dimethylolpropionic acid (DMPA) to synthesize organofluorine and silicon modified waterborne polyurethane (WPU). The effects of organofluorine and silicon on the properties of WPU emulsions and films were investigated. The results show that the purity of DFMA-IPDA was 99.2%, which can used for preparation of stable WPU emulsions with certain amount of PDMS. As the amount of PDMS and/or DFMA-IPDA increased, the average particle size of the emulsions increased and the thermostability, water resistance and surface water contact angle of the resultant films was also improved. PDMS modification led to an increase in the flexibility of the films, whereas the DFMA-IPDA modification can improve their toughness. Thus, PDMS and DFMA-IPDA co-modified WPU behaved excellent comprehensive properties. When DFMA-IPDA was used as extender and the amount of PDMS was 4 wt%, the water absorption rate of the film of WPU was 4.5% and their water contact angle was 102°.