Non-Isocyanate Polyurethanes from Thiocarbonates

Patent Title: PROCESS FOR THE MANUFACTURING OF A POLYMER WITH URETHANE GROUPS

Number/Link: WO2019/034470 and WO2019/034473

Applicant/Assignee: BASF

Publication Date: 21 February 2019

“Gist”:  A cyclic thiocarbonate is reacted with a diamine and then with a diacrylate

Why it is interesting: NIPU is prepared by reacting a five-ring monothiocarbonate with di- (or poly-) amine and then with a compound having at least two thiol-reactive functional groups like e.g. ethylenically unsaturated groups. The reaction has advantages over conventional PU chemistry like being isocyanate-free, less moisture sensitive and running at moderate temperatures. In an example methyl monothiocarbonate is reacted with 1,5-pentanediamine and 1,4-butandioldimethacrylate, resulting in a colourless, transparent polymer with a high thermal stability.
An interesting take on hybrid non-isocyanate polyurethanes.

scheme1

Reaction scheme according to the invention

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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

Flexible Foams with Reduced Aldehyde Emissions

Patent Title: POLYURETHANE FOAMS HAVING LOW LEVELS OF ALDEHYDE EMISSIONS

 Number/Link: WO2018/145283

Applicant/Assignee:   Dow

Publication date: 16 August 2018

Gist”: Cyclic 1,3-diketones are used as aldehyde scavengers

Why it is interesting: Aldehyde emissions from flexible polyurethane foams (and many other materials) remain an issue and have been discussed a number of times before in this blog.  The current invention is about the use of cyclic 1,3-diketones as scavengers for both fomaldehyde and acetaldehyde in flexible foam formulations.  Diketones like (e.g.) 5-phenylcyclohexane-1,3-dione, 5,5-dimethylcyclohexane-1,3-dione and 1H-indene-1,3(2H)-dione are blended with the polyol component and react with the aldehydes during foam cure.

DMCHD

5,5-dimethylcyclohexane-1,3-dione