Polyols from Natural Oils using the Alkyne Zipper Reaction

Title: POLYURETHANE MATERIALS FORMED FROM UNSATURATED PLANT OILS VIA AN ALKYNE ZIPPER REACTION

Number/Link: US2017/0166679 US2017/0166680

Applicant/Assignee: IBM

Publication Date: 15-june-2017

“Gist”: Oils are turned into alkyne alcohols, ‘zippered’ and oxidized to polyols

Why it is interesting: This is yet  another IBM patent application about interesting, albeit somewhat exotic, chemistry and featuring only “prophetic” examples. In this case unsaturated natural oils are first converted into unsaturated alcohols and then into alkynes by bromination and elimination.  The internal alkynes are then converted to terminal alkynes by an “alkyne zipper reaction” and then into hydroxyl groups by hydroboration and epoxidation/ring-opening. This series of reactions should result in polyols having two primary- and one or more secondary OH groups, useful, for example, for the preparation of sound absorbing foams.

Reaction sequence according to the invention

Sound Absorbing PU-PA Foams

Title: THERMOFORMABLE RIGID POLYURETHANE-POLYAMIDE FOAM

 Number/Link: US2014/058005

Applicant/Assignee: BASF

Publication date: 27-2-2014

Gist”: Rigid, open-celled and thermoformable polyurethane-polyamide foams are produced using short chain di-acids as both chain extender and blowing agent.

Why it is interesting: The reaction of a carboxylic acid group with an isocyanate group results in a mixed anhydride, which after releasing carbon dioxide forms an amide. Because the reaction is relatively sluggish a  Lewis base catalyst is used, e.g. N-methylimidazole. In this case a rigid foam-forming formulation based on MDI and (pref.) polyether polyols is further reacted with short chain diacids like azelaic- or glutaric acid.  The examples show foam densities of less than 30 kg/m³ without the use of water.  The foams are open celled with high air flow and with a Tg of around 90°C, making them thermoformable.  This type of foams is used as acoustic bonnet- en roofliners in the automotive industry.

Azelaic Acid

Azelaic Acid