TPU with Reduced Blooming

Patent Title: POLYOLS WITH REDUCED CYCLIC OLIGOMER CONTENT AND THERMOPLASTIC POLYURETHANE COMPOSITIONS THEREOF

 Number/Link: WO2017040505

Applicant/Assignee: Lubrizol

Publication date: 9-mar-2017

Gist”: Enzymes are used to remove cyclo-oligomers from polyster polyols

Why it is interesting: It is known that the “blooming” of polyester TPUs (i.e. the fomation of a white surface haze) is caused by the migration of cyclic polyester oligomers to the surface of the TPU. Conventionally these unreactive cyclo-oligomers are removed by e.g extraction, or their formation is prevented by careful choice of diol and diacid as mentioned before in this blog. According to this invention the cyclic polyesters can be removed by treating the polyol with an enzyme. Enzymes of the lipase or cutinase type are immobilized by attachement to an inert and insoluble material and then heated together with the polyol at 70 to 90ºC to ‘cut’ the polyester rings. After treatment of the polyol the immobilized enzyme can be filtrated.

A cyclic diester

Leave a comment

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s