Polyurethane dispersion for use as binder, e.g. in paint or adhesives, contains mixture of polymeric polyol, low-mol. wt. polyol, anionically-modifiable polymeth-acrylate-diol, polyisocyanate, neutralizing agent and water

摘要

Polyurethane dispersions with high film hardness, in which the reaction components include (A) 3-25 wt% polyol component comprising (i) a polymeric polyol with 2 or more reactive hydroxyl groups and (ii) a low-mol. wt. polyol and (B) 3-30 wt% anionically-modifiable 1,2-polymethacrylate-diol with 2 reactive OH groups and inert carboxyl group(s). Polyurethane dispersions with high film hardness, containing (A) 3-25 wt% polyol component comprising (i) 2-20 wt% polymeric polyol with 2 or more isocyanate-reactive hydroxyl groups and a mol. wt. of 500-4000 and (ii) 0.5-5 wt% low-mol. wt. polyol with 2 or more reactive OH groups and a mol. wt. of 50-500; (B) 3-30 wt% anionically modifiable 1,2-poly-methacrylate-diol with 2 reactive OH groups, one or more carboxyl groups which are inert towards polyisocyanates and a mol. wt. of 500-5000; (C) 2-20 wt% polyisocyanate component comprising polyisocyanate(s) or their homologues or derivatives with 2 or more aliphatic or aromatic NCO groups; (D) 0-6 wt% solvent comprising (i) organic solvent(s) which are inert towards polyisocyanates and which remain(s) in the hybrid polyurethane-polymer dispersion or may be partly or completely removed by distillation and/or (ii) reactive diluent which is inert towards polyisocyanates, consisting of inert organic compound(s) with radically polymerizable double bond(s); (E) 0.15-1.5 wt% inorganic or organic base(s) as neutralizing agent; and (F) 0-1 wt% chain-extender comprising polyamine(s) with 2 or more reactive amino groups, and water (to make up 100 wt%).