Self-Cross-Linkable Anionic Waterborne Polyurethane–Silanol Dispersions from Cottonseed-Oil-Based Phosphorylated Polyol as Ionic Soft Segment

Phosphorylated polyols (phospols) derived from cottonseed oil (CSO) were employed to synthesize novel, DMPA- (dimethylol propanoic acid-) free, catalyst-free, waterborne polyurethane dispersions (PUDs). Three different phospols bearing both hydroxyl and ionizable phosphoryl groups were synthesized through the ring-opening hydrolysis of epoxidized cottonseed oil (ECSO) in the presence of ortho-phosphoric acid. The phospols were characterized by 1H NMR spectroscopy, FTIR spectroscopy, and gel permeation chromatography. Three phospols (phospol-P5, -P10, and -P15) having hydroxyl numbers of 130, 160, and 180 mg of KOH/g, respectively, were used as internal emulsifiers in waterborne PUDs with isophorone diisocyanate and 3-aminopropyltriethoxysilane (APTES). All three PU dispersions showed excellent storage stabilities (>6 months), and the average particle sizes of the PUDs ranged from 30 to 68 nm. The cured films were characterized by FTIR (ATR) and solid-state 29Si NMR analyses. The hydrophobicities of the fi...