Title: POLYURETHANE FOAMS AND METHOD FOR PRODUCING SAME
Number/Link: US2017/0174818
Applicant/Assignee: Lubrizol
Publication Date: 22-june-2016 (PCT oct. 2015)
“Gist”: TPUs with specific MW and polydispersity are injection moulded together with cellopener and gas in supercritical state
Why it is interesting: The invention relates to injection moulded “flexible foams”, especially useful for footwear applications. Thermoplastic polyurethanes with a Mw of 120,000 to 500,000 and a dispersity index of 1.85 to 2.51 are foamed using a gaseous blowing agent (CO2 or C1 to C6 hydrocarbons etc. ) together with a cellopener (silicone or EO/PO surfactant), such that at least 50% of cells are open. In the examples the blowing agent is added in supercritical state to the melt before injection moulding. The type of gas used, nor the densities of the foams are mentioned. Foaming TPU with gas in supercitical has also been file by Nike as discussed before in this blog.
Nike shoe with foamed thermoplastic midsole
Innovation in Polyurethanes 
Gerhard Bleys
/ June 23, 2017One of the (many) things that are strange about this case is the use of conventional flex foam cellopeners in an injection moulded TPU..