Patent Title: BIO-BASED DIISOCYANATE AND CHAIN EXTENDERS IN CRYSTALLINE SEGMENTED THERMOPLASTIC POLYESTER URETHANES
Number/Link: WO2016041076
Applicant/Assignee: Trent University
Publication date: 24-03-2016
“Gist”: TPU with highly crystalline hard segment is based on 1,7 heptamethylenediisocyanate
Why it is interesting: According to this application, polyester TPUs with crystalline hard segments can be produced using 1,7-heptamethylenediisocyanate. The HPMDI is reacted with a 2000MW poly(ethyleneadipate) diol and a short chain diol as chain extender. The TPUs show a high hard-segment crystallinity, resulting in improved phase separation and in a (semi-)crystalline softphase which has a significant reinforcement effect. The TPUs are thermally stable up to 250°C and show a toughness and strength comparable to conventional TPUs. HPMDI can reportedly be made from natural oils using the Curtius rearrangement – but no reference is given.
Curtius Rearrangment
Dr. Joop Koster
/ May 31, 2017As to the mentioned aliphatic isocyanate , this is not an easy way. This type of structure / segments analysis can also be done with adipic acid , 1,6-hexanediol and HDI isocyanate . I wonder if the differences will be that great. Looks a bit like ” l’art pour l’art ” .
Gerhard Bleys
/ June 2, 2017Indeed, but you’ll notice that the claim is actually much wider.