More Non-Isocyanate Polyurethanes

Title:  METHOD FOR PREPARING POLY(CARBONATE-URETHANE) OR POLY(ESTER-URETHANE)

 Number/Link: US20130144027

Applicant/Assignee: CENTRE NAT RECH SCIENT; TOTAL RES & TECHNOLOGY

Publication date: 6-06-2013 (priority PCT/EP)

Gist”: Non-isocyanate polycarbonate- or polyester- polyurethane with very high softblock molecular weight produced by “immortal” ring opening polymerization.

Why it is interesting: Non-isocyanate PU systems appear to become a growing trend – at least in scientific and patent literature. In addition to not using phosgene or isocyanates, advantages quoted are improved biodegradability and recyclability.  The current invention teaches the use of “immortal” ringopening polymerization to polymerize 5,6 or 7 membered cyclic carbonates or cyclic esters. This type of ROP is highly efficient and is described in e.g. US2011092664.  The resulting polymer is subsequently modified with anhydrides to a polymer with carboxylic end-groups, which are then reacted with cyclic carbonates bearing hydroxyl groups.  The resulting polymer has a MW of (preferably) 50,000 to 100,000 and can be reacted with polyamines to produce the polyurethanes. See the reaction scheme below.

Reaction sequence according to the invention

Reaction sequence according to the invention

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Self-Crosslinking Polyhydroxyurethanes for Imitation Leather

Title: SELF-CROSSLINKABLE POLYHYDROXY POLYURETHANE RESIN, RESINACEOUS MATERIAL THAT CONTAINS THE RESIN, PROCESS FOR PRODUCTION OF THE RESIN, AND IMITATION LEATHER, SURFACING MATERIAL AND WEATHERSTRIP MATERIAL, USING THE RESIN

 Number/Link: US2013/0095715

Applicant/Assignee: UKIMA CHEMICALS & COLOR

Publication date: 18-04-2013 (priority publication PCT/JP)

Gist”: Poly(hydroxyurethanes) prepared form cyclic carbonates and amines are modified by incorporating blocked isocyanate groups.  The latter can be heat-activated resulting in a self-crosslinking system useful for imitation leathers.

Why it is interesting: Poly(hydroxurethanes) can be produced without isocyanates from cyclic carbonates and amines (see previous posts in this blog on the subject of isocyanate-free polyurethanes) but for the production of imitation leathers (both “synthetic” and “articial” leathers) these materials reportedly are inferior to conventional urethanes. In this invention part of the OH groups of the hydroxyurethanes are reacted with “modifiers”  containing at least one isocyanate group and at least one blocked (or “masked”) isocyanate group.  The resulting resin can be used (as such or in a suitable solvent) in an imitation leather production process and can be ‘self’- crosslinked by heat-activating the blocked isocyanate groups, improving properties.

Example of a "modifier" according to the invention. "Y" is the blocking agent.

Example of a “modifier” according to the invention. “Y” is the blocking agent.

Polyurethane Particles Produced Without Isocyanates

Title: POLYHYDROXYURETHANE MICROPARTICLES, AND PROCESS FOR PRODUCING SAME

 Number/Link: WO2012150684  (in Japanese)

 Applicant/Assignee: DAINICHISEIKA COLOR CHEM

Publication date: 8-11-2012

Gist”: Polyhydroxyurethane microparticles produced form cyclic carbonates and amines. 

Why it is interesting: For a number of years non-isocyanate (hydroxy-)polyurethanes have been promoted by Oleg Figovsky (a.o.) without much success. However now and then this chemistry pops up again, usually related to coating systems.