Phosgene-Free Polyisocyanate with PDMS Backbone

Patent Title: MULTI-FUNCTIONAL CARBAMATE HAVING SOFT-SEGMENTS, POLYISOCYANATE OBTAINED VIA SUBSEQUENT NON-PHOSGENE SYNTHESIS METHODS, URETHANE PREPOLYMER AND ELASTOMERIC URETHANE HAVING SOFT-SEGMENTS DERIVED THEREFROM, AND PREPARATION METHOD THEREOF

 Number/Link: US20180186918

Applicant/Assignee:  Great Eastern Resins Industrial

Publication date: 5 July 2018

Gist”: Biscarbamate with PDMS softblock backbone is heat-cracked into diisocyanates

Why it is interesting: The invention relates to isocyanate-capped “softblock” siloxanyl prepared without using phosgene and polyurethanes derived therefrom. The invention is accomplished by reacting relatively high MW polydimethylsiloxanediamines with diphenylcarbonate.  The resulting biscarbamate is heated under reduced pressure to produce the diisocyanate and to remove the phenol by-product.  The isocyanates can be reacted with polyols and/or chain extenders to produce highly hydrophobic polyurethanes with low surface tension and good chemical resistance.

biscarbamate

Biscarbamate with PDMS backbone

 

Sequence-Defined Polyurethanes for Information Storage

Patent Title: UNIFORM SEQUENCE-DEFINED POLYURETHANES AND USES THEREOF AS MOLECULAR LABELS

 Number/Link: WO2017/194694

Applicant/Assignee:  Centre National de la Recherche

Publication date: 16 November 2017

Gist”: Stepwise immobilized polymer synthesis is used to make polyurethane having a predefined sequence of monomers

Why it is interesting: The invention is about monodisperse polyurethanes consisting of a well-defined sequence of monomers having various chain lengths and side groups – not unlike proteins or nucleic acids. In a first step a solid support (e.g. polystyrene beads) which bears a cleavable tether molecule is reacted with N,N’-disuccinimidylcarbonate and in a second step with an aminoalcohol like 5-amino-1-pentanol. Steps 1 and 2 are then repeated using the same or a different aminoalcohol. Finally the tether is cleaved from the support.  If 2 different aminoalcohols are used, a binary code can be encoded in the molecule which can later be read using a sequencing technique. The polyurethanes are said to be useful in anti-counterfeiting technologies.

Capture1

Reaction sequence according to the invention

Thiol-Crosslinked Poly(hydroxyurethanes)

Title: METHOD FOR PRODUCING OR CURING POLYMERS USING THIOL-ENE POLYADDITION REACTIONS

Number/Link: W2017/081120

Applicant/Assignee:  Henkel

Publication Date: 18-05-2017

“Gist”: Unsaturated PHU are crosslinked using polythiols

Why it is interesting: The invention is about poly(hydroxyurethanes) (PHU) containing alkylene groups that are crosslinked using thiol-ene ‘click’ polyaddition reactions. The unsaturated PHU are first prepared by aminolysis of cyclocarbonates using unsaturated amines. In an example di-trimethylolpropane is converted to di-trimethylolpropanedicarbonate using ethylchloroformiate.  The di-TMPDC is then reacted with 3-aminopropylvinylether to prepare the PHU, which is then crosslinked using pentaerithritol-tetra(3-mecaptopropionate) in the presence of a photoinitiator and UV light.  The invention is said to be useful for isocyanate-free adhesive- and coating systems.

Di-trimethylolpropanedicarbonate