PCM-Containing Viscoelastic Foams

Patent Title: VISCOELASTIC POLYURETHANE FOAM WITH COATING

Number/Link: WO2017/210439

Applicant/Assignee: Dow

Publication date: 7 December 2017

“Gist”: Open-celled visco-foam is impregnated with an aqueous dispersant composition containing a phase change material

Why it is interesting: According to Dow, open-celled viscoelastic polyurethane foams can be prepared by using a acid-modified polyolefin latex cellopener, as discussed before in this blog. In the current invention these open-celled foams are impregnated with an aqueous composition comprising an ionomer (a sodium salt of a maleic anhydride copolymer) and a microencapsulated PCM. The composition is said to ‘coat’ the cell struts with PCM and increase the comfort properties of the foam.
I wonder if with this process enough PCM can be in introduced to have a noticeable effect.

bluewave

Dow’s proprietary BLUEWAVE dispersion process is used to prepare the cellopening latex

Flexible PU Foam with Very Low Resilience

Patent Title: LOW-RESILIENCE POLYURETHANE FOAM AND PRODUCTION METHOD THEREOF

 Number/Link: US2016/0024268

Applicant/Assignee: Mitsui

Publication date: 28-01-2016

Gist”: Use of trans-BIC in viscoelastic flex foam

Why it is interesting: According to this invention low resilience flexible foams can be produced by reacting a mixture of two (optionally three) polyether polyols, water, a crosslinker and a catalyst with 1,4-bis(isocyanatomethyl)cyclohexane (BIC) where the BIC consists of (pref) 90% or more of the trans isomer. Higher trans-isomer is said to result in higher airflow and a finer cellstructure. In the examples a high MW all-PO triol and a low MW EO/PO triol with 18% EO tip is used, together with BIC at an NCO index of 70%.  The resulting foams have a high airflow and a (very) low resilience at densities between 50 and 70 kg/m³. While trans-BIC is clearly an interesting aliphatic di-iso, it is not widely available.

trans-1,4-bis(isocyanatomethyl)cyclohexane

trans-1,4-bis(isocyanatomethyl)cyclohexane