Omniphobic Polyurea

Patent Title: MOISTURE-CURABLE OMNIPHOBIC COATINGS

Number/Link: US2019/0031909

Applicant/Assignee: US Navy

Publication Date: 31 January 2019

“Gist”: Polyurea topcoat containing both silane and perfluoro groups

Why it is interesting: According to this invention, a coating having both hydrophobic and oleophobic properties can be prepared by reacting an alkoxysilane-terminated polyurea with a perfluoromaterial having at least one alkoxy- or hydroxyl group. In an example a coating is prepared by reacting a polyurea based on HDI trimer and N-butyl-3-aminoppropyltrimethoxysilane with triethoxy(perfluoro-octyl)silane. The coating showed contact angles of more than 140 degrees vs water and more than 90 degrees vs hexadecane.

omniphobicpolyurea

Reaction system according to the invention

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PU Elastomers with Extremely High Elongation

Patent Title:  Polyurethane Elastomer with High Ultimate Elongation

 Number/Link: US2018/0312623

Applicant/Assignee:  UNIV PENNSYLVANIA

Publication date: 1 November 2018

Gist”: Low hardblock polyurethane-polyurea elastomers are prepared from low unsat diols, HDI and a bulky diamine chain extender

Why it is interesting: The current invention relates to PU  elastomers which are said “to  have the highest reported elongation-at-break among known polyurethane elastomers“. The materials are prepared from an NCO-ended prepolymer consisting of a low unsaturated, low dispersity diol and a symmetric diisocyanate (i.e. no 4,4′-MDI), which is reacted with a “bulky” diamine chain extender. In the examples Acclaim 4200 (polyether diol with OHv 28) is used together with HDI and 2-methyl-1,5-pentanediamine. The elastomer showed an elongation at break of more than 2000%.
Because these materials have a low- and non-aromatic hardblock content, it is my opinion that they show creep rather than elasticity.

methylpentandiamine

2-methyl-1,5-pentanediamine

Degradable Polyurethane Elastomers

Patent Title: DEGRADABLE EXTRUSION RESISTANT COMPOSITIONS AND ARTICLES OF MANUFACTURE

 Number/Link: WO2018/013288

Applicant/Assignee:  Baker Hughes Inc.

Publication date: 18 January 2018

Gist”: Polyester-PU elastomers are compression moulded together with fine particles of acid or base

Why it is interesting: The invention is about moulded polyurethane parts for use as temporary components in boreholes and which can be controllably degraded. The degradability is achieved by compression moulding polyester PU elastomers together with an acidic or basic fine powder.  In an example a polyester-TDI ‘full’ prepolymer is reacted with 1,3-propanediol-bis-(4-aminobezoate) and compression moulded with a sulfamic acid powder. The moulded parts could be degraded within 2 weeks in water of 50-90°C.

vibracure

1,3-propanediol bis-(4-aminobenzoate)