One Component Polyurea

Patent Title: CYCLIC DYNAMIC POLYUREAS FOR POLYMERIC UREA PROCESSING

 Number/Link: WO2016/126756

Applicant/Assignee: University of Illinois

Publication date: 11-08-2016

Gist”: 1K polyurea coatings from thermoreversible cyclic urea oligomers

Why it is interesting: This application is related to W02016/069582 of the same applicant, discussed before on this blog. In this case the sterically hindered ureas are prepared in solvent and at a relatively low concentration. Under these conditions cyclic oligomers will be formed which can be separated and used as powder coatings, or, together with (e.g.) catalysts, polyols and crosslinkers, as liquid coatings. When heated the rings will open and the coating composition will cure. In an example 1,3-bis(isocyanatomethyl)cyclohexane  is reacted with N,N’-di-t-butyl ethylenediamine, in DMF, which forms cyclic oligomers at low-, and linear polymers at high concentrations.

Thermoreversible polyurea according to the invention

Thermoreversible polyurea according to the invention

 

Highly Tuneable Shape Memory Polyurethanes

Patent Title: PROCESSABLE, TUNABLE THIOL-ENE CROSSLINKED POLYURETHANE SHAPE MEMORY POLYMERS

 Number/Link: WO2016/126703

Applicant/Assignee: Texas A&M University

Publication date: 11-08-2016

Gist”: SMPUs are made from combinations of different diisocyanates and chain extenders and different levels of crosslinking using thiol-ene click chemistry

Why it is interesting: This invention is about shape memory polyurethanes with tuneable glass transition temperature and stiffness. In a first step a low mole weight TPU is prepared from a diisocyanate and a short chain diol including some trimethylolpropane allyether (TMPAE) and allylalcohol as chain stopper. The TPU is then blended with a polythiol and a photoinitiator to allow for UV curing. The Tg can be tuned from 30 and 105°C by combining different types of chain extenders and di-iso’s ranging from DEG-HDI to CHDM-H12MDI.  The modulus (in the rubber state) can be  varied between 0.4 to 20 MPa by controlling the level of crosslinking through the amount of TMPAE and amount and type of polythiol.  The SMPUs are said to be especially useful for biomedical applications.

Reaction scheme of the invention

Reaction scheme of 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

PET-Lignin Polyols

Patent Title: HIGH RECYCLE CONTENT POLYOLS FROM THERMOPLASTIC POLYESTERS AND LIGNIN OR TANNIN

 Number/Link: WO2016/118411

Applicant/Assignee: Resinate Materials Group

Publication date: 28-07-2016

Gist”: PET is glycolized and then reacted with lignin or tannin

Why it is interesting: This application is about ‘sustainable’ aromatic polyester polyols partly based on recycled materials and partly on biorenewable materials. According to the invention the polyols can be prepared by first glycolizing (waste) PET and subsequently reacting the mixture with lignin at 110-210°C while removing volatile condensation products.  The resulting polyols (pref) show a OH value between 40 and 400 mg KOH/g, a fn of 2-2.2 and a viscosity at 25°C of 500 to 3000 cP. In the examples polyols with up to 25 wt% lignin are shown. The polyols are said to be useful e.g. in 2K PU coating compositions.

Part of a lignin structure

Part of a lignin structure

Optical Polyurethane Elastomers

Patent Title: COMPOSITION FOR TRANSPARENT SHAPED BODIES BASED ON POLYURETHANE

 Number/Link: WO2016/113295

Applicant/Assignee: Covestro

Publication date: 21-07-2016

Gist”: Use of amino-chelate-tin complex as delayed action catalyst for transparent PU elastomers

Why it is interesting: Lenses for eyeglasses are increasingly made from transparent organic polymers like polyurethane elastomers. The production requires a specialized casting process into glass moulds, followed by an exact tempering over many hours. According to this invention polyurethane elastomers, useful for the production of eyeglass lenses, can be made form a composition containing a polyol, a cycloaliphatic or araliphatic diisocyanate, an internal mould release agent and a thermo-latent catalyst. The catalyst is an inorganic metal complex comprising Sn (preferred) and at least one tert-amine containing chelating ligand. The composition is said to have a longer ‘open-time’ as the catalyst-free system.

Example of thermo-latent catalyst according to the invention

Example of thermo-latent catalyst according to the invention

Follow

Get every new post delivered to your Inbox.

Join 694 other followers