Non-Isocyanate Polyurethane Using Thiol-Ene “Click Chemistry”

Title: POLY(HYDROXYL URETHANE) COMPOSITIONS AND METHODS OF MAKING AND USING THE SAME

 Number/Link: US20140182784

Applicant/Assignee:  Inventors but with US goverment interest

Publication date: 3-07-2014

Gist”: Crosslinked poly(hydroxyurethanes) are prepared by reacting a cyclic carbonate comprising a carbon-carbon double bond, a di-thiol and a polyamine.

Why it is interesting: According to this invention hydroxyurethanes are produced by first reacting a cyclic carbonate which has a double bond (e.g. 4-vinyl-1,3-dioxolan-2-one) with a dithiol (e.g. 1,6-hexanedithiol) using UV radiation and a UV initiator. The resulting di-carbonate is then reacted with a polyamine (e.g. diethylene triamine) resulting in a crosslinked poly(hydroxyurethane). Alternatively the carbonate-amine reaction can happen before the thiol-ene ‘click’ reaction. The materials can be used for binders and adhesives a.o.  The reactions have the advantage of being solvent-, catalyst- and isocyanate-free and having a high yield.

Thiol-ene reaction followed by carbonate-amine reaction

Thiol-ene reaction followed by carbonate-amine reaction

Using PU Foams as a Template for Silicone Foams

Title: FOAM-LIKE MATERIALS AND METHODS FOR PRODUCING SAME

 Number/Link:US2014/154491

Applicant/Assignee: Allergan

Publication date: 5-06-2014 (priority PCT/US)

Gist”: A polyurethane foam is impregnated with a curable liquid silicone.  After curing of the silicone the PU is removed.

Why it is interesting: According to this invention open celled polyurethane (or melamine) foam structures can be ‘converted’ into other materials like silicone, polyesters, polyolefins etc. by impregnating them with the the appropriate raw materials, curing and removing the ‘base’ foam. Optionally the ‘converted’ foam structure can be impregnated and cured again until the desired porosity is obtained.  In an example a PU foam was impregnated with a HTV silicone rubber.  After curing, the PU structure was removed using hydrogen peroxide.
While undoubtedly very interesting foam materials can be made in this way, the process seems messy and not very practical.

A 'base foam structure' (left has been impregnated and cured with another polymer (right).

A ‘base’ foam (left) and an impregnated foam (right) according to the invention.

 

A New Type of Ultra-Soft Thermoplastic Polyurethanes

Title: THERMOPLASTIC POLYURETHANES WITH CRYSTALLINE CHAIN ENDS

 Number/Link: WO2014/070426

Applicant/Assignee: Lubrizol

Publication date: 8-05-2014

Gist”: Easily processable, plasticizer-free ultra-soft TPU can be produced by incorporating a crystallizing polyolefin chain stopper.

Why it is interesting: It is well known that TPU with a shore hardness below about 65A is hard to produce and process because of its stickiness and low solidification/crystallization rate. According to the invention this problem can be solved by using a crystalline chain stopper in addition to the polyol, chain extender and di-isocyanate. The chain stopper is (preferably) a c20 to c70 polyolefin mono-alcohol. Apart from improving processability at low hardness, the incoproration of the olefin chain stopper also improves compatibility of the TPU with olefin thermoplastics.  The chain stopper can also be grafted with e.g. a vinyl alkoxysilane to make a hybrid crosslinkable TPU.  An interesting idea with many potential advantages and interesting effects.

Lubrizol logo

Lubrizol logo

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