TPUs from Block Polyester Polyols

Patent Title: THERMOPLASTIC POLYURETHANE HAVING HIGH TEAR PROPAGATION STRENGTH  & PROCESS FOR PRODUCING TRANSPARENT HARD THERMOPLASTIC POLYURETHANES

 Number/Link: WO2018/115460  WO2018/1154684

Applicant/Assignee:  BASF

Publication date: 28 June 2018

Gist”:  Polyester polyols containing a “hard block” of polyethyleneterephthalate are used in the preparation of TPU 

Why it is interesting: According to this invention thermoplastic polyurethanes with a high hardness at a relatively low hardblock level (<75%), or a high tear strength at relatively low Tg (<5°C) can be prepared from a polyester polyol that is a block copolymer containing 10-50% of an aromatic polyester block, the rest being aliphatic polyester. In the examples diols are prepared from PET together with adipic acid and BDO or DEG. The diols are reacted with MDI or HDI and a chain extender like BDO or HDO.

PET

Poly(ethyeleneterephthalate)

Degradable Polyurethane Elastomers

Patent Title: DEGRADABLE EXTRUSION RESISTANT COMPOSITIONS AND ARTICLES OF MANUFACTURE

 Number/Link: WO2018/013288

Applicant/Assignee:  Baker Hughes Inc.

Publication date: 18 January 2018

Gist”: Polyester-PU elastomers are compression moulded together with fine particles of acid or base

Why it is interesting: The invention is about moulded polyurethane parts for use as temporary components in boreholes and which can be controllably degraded. The degradability is achieved by compression moulding polyester PU elastomers together with an acidic or basic fine powder.  In an example a polyester-TDI ‘full’ prepolymer is reacted with 1,3-propanediol-bis-(4-aminobezoate) and compression moulded with a sulfamic acid powder. The moulded parts could be degraded within 2 weeks in water of 50-90°C.

vibracure

1,3-propanediol bis-(4-aminobenzoate)

 

Thermoreversible Polyurea

Patent Title: DYNAMIC UREA BONDS FOR POLYMERS

 Number/Link: W02016/069582

Applicant/Assignee: University of Illinois

Publication date: 6-05-2016

Gist”: Urea bonds prepared from sterically hindered amines and isocyanates

Why it is interesting: The N-C bond in urea is very stable due to conjugation of the lone electron pair of the nitrogen atom with the cabonyl group.  According to this invention, the nitrogen atom can be subsituted with a strongly hindering group such that the coplanarity, and therefore most of the conjugation, of the C-N and C=O bonds is lost. These hindered urea bonds are much less stable and can reversibly depolymerize at relatively low temperatures. Thermoreversible bonds can be useful in a number of smart materials such as self-healing-, “4D printing”- , and reprogrammable shape memory materials. In an example a shape memory material with a Tg of 53°C and a Young’s Modulus of about 2 GPa was prepared by reacting 2-(t-buylamino)ethanol (TBAE) and trimerized hexamethylene diisocyanate (THDI). The ‘permanent shape’ of the material could be re-programmed by forcing the material in a new shape for 72 hours at 60°C.

Polurethane-urea with thermoreverisble urea bonds

Poly(urethane-urea) with thermoreverisble urea bonds