Title: COPOLYMER POLYOL WITH FUNCTIONAL ADDITIVE IN DISPERSED PHASE
Number/Link: WO2017/053064
Applicant/Assignee: Dow
Publication date: 30-mar-2017
“Gist”: Polymer polyols are prepared by melt-dispersion of functionalized polystyrene in a carier polyol.
Why it is interesting: The preparation of polymer polyols by melt-dispersion is known and has been discussed before in this blog. According to this invention the thermoplastic to be dispersed is first pre-compounded with one or more ‘functional components’, like pigments, flame ratardants, high density fillers, etc. In the examples polystyrene is compounded with additives like TiO2 and flame retardants in a twin-screw extruder combined with a pelletizer. The molten pellets are then dispersed under shear in a polyether polyol together with a stabilizer. The stabilizer is a copolymer prepared from an unsaturated branched polyol and styrene.
The polymer polyols are useful for the production of PU flexible foams and elastomers.

SEM image of polymer polyol according to the invention