Title: CRYSTALLINE HIGH MODULUS THERMOPLASTIC POLYURETHANE

Number/Link:  WO2017079101  WO2017079188

Applicant/Assignee: Lubrizol

Publication Date: 11 May 2017

“Gist”: High-hardblock TPU using ‘stacking’ chain extenders and MDI

Why it is interesting: Thermoplastic polyurethanes with hardblock levels of 75% and higher were first patented by Upjohn in 1981 in a “classic” patent which has been discussed before in this blog. These materials – often marketed under the ‘ISOPLAST’ tradename- are usually produced from a diol, 4,4′-MDI and a (mixture of) chain extender(s) comprising a ‘non-stacking’ chain extender like cyclohexanedimethylol, neopentylglycol, MPdiol etc. to control crystallinity. In the current invention only ‘stacking’ chain extenders are used in an otherwise identical composition, resulting -unsurprisingly- in a more crystalline material with a higher modulus and melting temperature. It is also said that these materials are easier to compound with e.g. fire retardants.
Even if this idea were formally ‘new’ I doubt its inventiveness and therefore its patentability.

The famous ISOPLAST(TM) nail