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

UV Resistant Viscoelastic Foams

Patent Title: POLYURETHANE PRODUCT WITH SULFUR-CONTAINING POLYOL

 Number/Link: WO2018/111806

Applicant/Assignee:  Dow

Publication date: 21 June 2018

Gist”: VE foams using S-containing polyether polyols

Why it is interesting: According to this invention sulfur containing polyols improve the UV resistance of polyurethane materials.  It is believed that sulfur acts as a UV absorber incorporated into the polymer, thereby reducing the need for additives such as antioxidants.  In the examples an S-containing polyether diol is prepared by reacting 2,2′-thiodiethanol with propyleneoxide up to an OH value of  188 mg KOH/g. The diol is then used in an amount of 5 to 15% on the total polyol blend to prepare low resilience flexible foams showing an improved UV resistance.

 

TDE

2,2′-thiodiethanol