Patent Title: TELECHELIC PREPOLYMERS AND REACTION PRODUCTS THEREOF

 Number/Link: WO 2017/023506

Applicant/Assignee: University of Minnesota

Publication date: 9-feb-2017

“Gist”:  Diols are made by ROM polymerization of gem-dialkyl cyclooctene together with a symmetrical diol as chain transfer agent

Why it is interesting: According to this application, thermoplastic polyurethanes containing geminal dialkyl groups have far superior thermal stability, oxidative-, hydrolytic- and barrier properties as compared to TPUs containing conventional soft segments. Diols containing gem-dialkyl groups are prepared by ring-opening metathesis polymerization (ROMP) of a gem-dialkyl cyclooctene with a suitable catalyst and in the presence of a symmetrical aliphatic olefin chain transfer agent having functional end groups. Examples are 5,5-dimethylcyclooct-1-ene and 1,8-oct-4-ene diol as the chain transfer agent.  The resulting diol is then reacted with (e.g.) 4.4′-MDI to prepare the TPU.

5,5-dimethylcyclooct-1-ene