Hybrid Polyisocyanurates for Composites and Coatings

Patent Title: DUAL-CURING ISOCYANURATE POLYMERS

 Number/Link:WO2018/087395 WO2018/087396  WO2018/087399 (German)

Applicant/Assignee:  Covestro

Publication date: 17 May 2018

Gist”:  Di-isocyanate trimer is reacted with hydroxymethacrylates and polyacrylates in the presence of a trimerization catalyst. 

Why it is interesting: According to these inventions a reaction system with two curing modes can be prepared by mixing high functionality oligomeric isocyanate, ethylenically unsaturated compounds, unsaturated compounds containing isocyanate-reactive groups, timerization catalyst and a free-radical initiator at an NCO index of 100 to 200. The system shows a relatively low viscosity and can e.g. be used in fiber-reinforced composites and in coatings. In the examples HDI trimer is reacted with hexanedioldimethacrylate and hydroxypropylmethacrylate in the presence of potassium acetate and a peroxybenzoic acid.

HDI isocyanurate

HDI-trimer


TPU/PU-Acrylate Semi-IPNs

Patent Title: THERMALLY STABLE MICROSTRUCTURED SEMI-IPN LAYER

 Number/Link: WO2016/191118

Applicant/Assignee: 3M

Publication date: 1-dec-2016

Gist”:  TPU and PU-acrylate oligomers are blended and radiation-cured

Why it is interesting: According to this invention semi-interpenetrating polymer networks (IPNs) that are prepared from thermoplastic polyurethane (or urethane/urea) and acrylate-functional polyurethane oligomers are highly heat-stable and abrasion resistant and can be used for the production of microstructured surfaces.  Microstructured (‘riblet’) surfaces with dimples or ridges of a few to a few hundred microns deep are used as drag reducing coatings on planes, ships and in aeronautics. In the examples 90% of a commercial TPU is blended and co-extruded with 10% of a commercial aliphatic urethane acrylate oligomer.  The extruded film was then laminated on on a microreplicated liner, radiation cured and removed from the liner to produce the riblet surface.

Microstructured layer according to the invention

Microstructured layer according to the invention

Dispersions of Comb-Structured Polyurethanes

Patent Title: POLYURETHANE-BASED BINDER DISPERSION

 Number/Link: WO2016122569

Applicant/Assignee: Hewlett-Packard

Publication date: 4-08-2016

Gist”:  Aqueous dispersions of “1,2”-dihydroxypolyacrylate -based polyurethanes

Why it is interesting: According to this invention aqueous dispersions can be made of “comb -structured” polyurethanes which are based on polyols having two hydroxyl groups at one end of the chain.  The “1,2”-diols are made by copolymerizing (e.g.) methylmethacrylate and n-butylmethacrylate together with thioglycerol up to a Mw of about 2000. The polyols can then be reacted with isocyanate and dimethylolpropionic acid for dispersion in water. The dispersions are said to have a small average particle size (10-100 nm) and be especially useful as binders for inkjet-ink.

Thioglycerol

Thioglycerol