Low Viscosity Polyester Polyols

Patent Title: LOW VISCOSITY POLYOLS FOR POLYURETHANE APPLICATIONS

Number/Link: WO2019/010018

Applicant/Assignee: Stepan

Publication Date: 10 January 2019

“Gist”: Polyester polyol containing lactide

Why it is interesting:  The invention relates to low viscosity polyester polyols for use in crosslinked polyurethane coating compositions. The polyols are prepared from a polycarboxylic acid, one or more polyols and 5-35% lactide. In an example adipic acid is reacted with lactide, neopentyl glycol and trimethylolpropane. Coatings made from these polyols are said to have improved hardness and solvent resistance and a low VOC content.

lactide

Lactide

Novel i-PEEP Polymers

Patent Title:  ISOCYANATE-MODIFIED POLYESTER-EPOXIDE POLYMER COMPOSITIONS

 Number/Link: WO2018/160217

Applicant/Assignee:  Stepan

Publication date: 7 September 2018

“Gist”: Polyester polyols are reacted with isocyanates and polyepoxies

Why it is interesting: The invention is related to isocyanate-modified polyester-epoxy polymers (i-PEEPs) which are said to be a “new class of polymers” useful as adhesives, coatings and elastomers.  The materials are prepared by reacting polyester polyols with both polyisocyanates and polyepoxies at an “i-PEEP index” (=(eqvs iso + eqvs epoxy)/eqvs polyol in %) of 100 to 200. The reaction can be run catalysed at room temperature or optionally un-catalyzed at 40 to 100°C. In the examples aromatic and aliphatic polyester polyols are reacted with polymeric MDI and BPA-DGE – based polyepoxide at different indices to produce elastomers with shore A hardness ranging between 30 and 95.
Interesting materials, although calling them a new class of polymers may be a bit exaggerated.

Bisphenol_A_diglycidyl_ether_200

Bisphenol-A diglycidylether (BPA-DGE)

 

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  WO2018/115464

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)