Tack-Free Polythiourethane Gels

Patent Title: SOFT ISOCYANATE-CROSSLINKED POLYMER SUBSTANCE AND ASSOCIATED PRODUCTS

 Number/Link: WO2017/054797 (German)

Applicant/Assignee: Technogel

Publication date: 6-april-2017

Gist”: Tack-free polyurethane gels are made from polythiols

Why it is interesting: Very soft polyurethane elastomers or “gels” can be made using high functionality isocyanate and monols (as co-invented by myself – e.g. EP1389222 ) or by reacting a high functionality polyol/siocyanate system at low isocyanate-index (as invented by Bayer – later spun off as Technogel).  PU gels are useful as shock dampers, gaskets and cushions but are always tacky and need to be covered or wrapped, which changes their damping and hardness characteristics. According to this invention tack-free gels without the need for covering can be produced by using polythiols instead of polyols, resulting in poly(thiolurethanes) instead of polyurethanes. This is interesting and surprising and I wonder if it would work with the monol-gels as well.

thiolurethane

Thiolurethane linkage

Flexible Foams with Enlarged Cell Size

Title: PUR FOAM WITH ENLARGED CELL STRUCTURE

 Number/Link: WO2014/170198 (German)

Applicant/Assignee: Evonik

Publication date: 23-10-2014

Gist”: The cell size of PU flexible foam is enlarged by using microcrystalline wax.

Why it is interesting: Enlarging the cell size of flexible foams can improve comfort properties by enhancing ‘breathabibility’, that is by enhancing airflow and moisture- and heat transport.  According to this invention the cell size of flex foams can be increased without affecting foam density or hardness by using a specific type of wax.  The wax (preferably) is a microcrystalline wax (as opposed to a paraffinic wax) with a congealing temperature of between 60 and 75°C.  The wax is used as a dispersion in a solvent (e.g. a sorbitan ester)  in an amount of about 0.05 to 2.0 php.

Cell structure of a flexible polyurethane foam.

Cell structure of a flexible polyurethane foam.

  • Pages

  • Categories

  • Enter your email address to follow this blog and receive notifications of new posts by email.

    Join 1,090 other followers

  • Follow Innovation in PU on Twitter

%d bloggers like this: