Patent Title: POLYURETHANES WITH GOOD PERMEABILITY FOR ELECTROMAGNETIC RADIATION

Number/Link: WO2019/002350 (German)

Applicant/Assignee: BASF

Publication Date: 3 January 2019

“Gist”:  TPU based on aliphatic polycarbonate diol

Why it is interesting: The invention relates to thermoplastic polyurethanes with a high permeabilty to electromagnetic radiation, especially in the 0.5 to 3 GHz frequency range. (I assume these materials are aimed at mobile phone covers and the like). ‘Surprisingly’ it was found that such TPUs can be prepared from polycarbonate diols which are based on butanediol, pentanediol or hexanediol. In the examples, TPUs based on these diols together with BDO and 1,6-HDI or 4,4′-MDI, show a lower dielectric loss factor at 400 MHz as compared to TPUs based on other polyols.

TPU mobile phone case.