Self-Healing Polyurethane Coatings

Patent Title: Self-Repairing Polyurethane Networks

 Number/Link: US20160289495

Applicant/Assignee: Clemson University

Publication date: 6-10-2016

Gist”: Polyurethane networks with alkylated polysaccharide moiety show self-healing properties

Why it is interesting: Chitosan (pref.) is alkylated by reacting with dodecylaldehyde (in solvent) and reducing the resulting imine with sodium cyanoborohydride. The alkylated chitosan is then reacted with isocyanate and polyol.  When used as coating, the material is claimed to show self-healing properties when irradiated with UV light. Modifying the composition by incorporation of catechol, or by changing the saccharide allows for materials which ‘heal’ when exposed to ferric ions or carbon dioxide. No explanation for this behaviour is given and it is not immediately clear to me why this should work.

Self-healing network according to the invention. The isocyanate used was (E)-3,5-bis(6-isocyanatohexyl)- 6-( ( 6-isocyanatohexyl)imino )-1,3,5-oxadiazinane-2, 4-dione.

Self-healing network according to the invention. The isocyanate used was (E)-3,5-bis(6-isocyanatohexyl)-6-( ( 6-isocyanatohexyl)imino )-1,3,5-oxadiazinane-2,4-dione. ALK= alkyl, POL=polyol.



Dianhydrohexitol-Based TPU


 Number/Link:  WO2016/055731  (French)

Applicant/Assignee: Roquette Freres

Publication date: 14-04-2016

Gist”: Use of isosorbide as chain extender for TPU preparation

Why it is interesting: According to this invention the use of dianhydrohexitols as chain extender results in thermoplastic polyurethanes with improved overmoulding properties, notably improved colour, abrasion resistance and soft touch. In the examples TPUs prepared from 4,4’MDI, PTMEG 1000 and chain extended with isosorbide are compared to 1,4-butanediol extended TPUs. The isosorbide TPUs are softer with better abrasion resistance and -in my opinion surprisingly- have a somewhat brighter colour.




  • Pages

  • Categories

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

    Join 1,089 other subscribers
  • Follow Innovation in PU on Twitter

%d bloggers like this: