Modified Polyisocyanurates

Patent Title: MODIFIED POLYISOCYANURA TE PLASTIC AND METHOD FOR PRODUCTION THEREOF

 Number/Link: WO2017/182108 WO2017/182109  WO2017/182110  (German)  

Applicant/Assignee:  Covestro

Publication date: 26-october-2017

Gist”: Partially trimerized diisocyanates are modified with monofunctional isocyanate-reactive compounds before complete trimerization

Why it is interesting: This series of applications relates to transparent polyisocyanurate coatings with controlled hydrophilicty, hydrophobicity, high scratch resitance etc. According to the invention trimers of diisocanates are reacted with a sub-stoichiometric amount of monofunctional hydrophobic, hydrophilic or siloxane-containing compounds, and then completely trimerized. In the examples HDI-trimer (prepared by partially trimerzing HDI and removing the rest of the monomer by thin film distillation) is reacted with e.g. methoxyPEG 500, dodecanol, perfluoroheptanol and N-(3-trimethoxyxilylpropyl)foramide and then trimerized using potassium acetate as catalyst.  The materials can e.g. be used as anti-fog coatings on optical lenses or anti-fingerprint coatings on cell phones.

HDI-isocyanurate

Viscoelastic Polyurethane Elastomers

Title:  IMPACT PROTECTION FOAM

Number/Link: US2017/0233519

Applicant/Assignee: Dow

Publication Date: 17 august 2017

“Gist”: Viscoelastic foams are prepared from MDI, castor oil and a hydrophilic polyether polyol.

Why it is interesting: According to this invention energy absorbing foams with relatively low density and a low hardness and resilience in the temperature range from about -10 to +40°C, can be produced by reacting a blend of hydrophilic and hydrophobic polyols containing castor oil, about 0.5 pbw water and some catalyst and chain extender with MDI.  The examples show foams of about 500 kg/m³ with hardness below shore 50A and ball rebound below 15% at both -10 and +23°C. The foams are said to be useful for impact-protective garments.

Castor oil

Castor oil component

PU-FPOSS Coating Compositions

Title: ICE ADHESION REDUCING PREPOLYMERS AND POLYMERS

Number/Link: US20170204291

Applicant/Assignee: Boeing

Publication Date: 20 July 2017  (published as PCT)

“Gist”: Ice repellent polyurethane coatings are prepared by incorporating F-POSS prepolymers

Why it is interesting: The invention is about coated surfaces that show reduced ice formation and/or adhesion. This is accomplished by incorporating fluorinated polyhedral oligomeric silsesquioxanes (F-POSS) into the composition. OH-functional F-POSS is prepared as per the scheme below, which is then reacted with polyisocyanates to prepare an NCO-functional F-POSS prepolymer.  The prepolymer can then be used in PU coating compositions, or reacted with amino-functional PDMS compounds and used as an additive in coating compositions.
It is believed that the F-POSS particles interfere with H-bond formation of ice to the coated surface.  Ice repellent surfaces are particularly useful for aircraft, wind turbines, cooling equipment an the like.

Synthesis of OH-functional trifluoropropyl POSS

Preventing Ostwald Ripening in Rigid PU Foams

Title: PRODUCTION OF FINE CELL FOAMS USING A CELL AGING INHIBITOR

Number/Link: WO2017093058  (German)

Applicant/Assignee: Evonik

Publication Date: 8 June 2017

“Gist”: Perfluorinated hydrocabons reduce Ostwald ripnening in PU foam formulations

Why it is interesting: Polymeric foams form by nucleation and growth of gass bubbles in the reacting mixture followed by (or simultaneous with) ageing of the bubbles through coalesence and Ostwald ripening, i.e. the growth of larger bubbles at the expense of smaller bubbles. Ostwald ripening ultimately results in fewer and larger cells, which has a negative effect on the thermal insulation properties of rigid foams. According to this invention the ripening effect can be prevented or reduced by incorporating in the foam formulation an “Ostwald hydrophobe”, i.e. a highly hydrophobic liquid which is largely immiscible with the reacting mixture. Examples of such liquids are perfluorinated hydrocabons with a boiling point of less than 150°C, e.g. perfluoropentane, perfluorocyclohexane and perfluoroisohexene (used in the examples).

Perfluorocyclohexane

 

Matte, Self-Healing Polyurethane Powder Coatings

Title: POLYURETHANE COATING COMPOSITION

Number/Link: WO2017/074835

Applicant/Assignee: Valspar

Publication Date: 4 May 2017

“Gist”: Coating composition comprising isocyanate and two polyester polyols having a similar Tg but a widely different equivalent weight.

Why it is interesting: Conventionally low gloss or “matte” coatings are the result of a microtextured surface achieved by certain fillers or by incompatible polymers and the like. According to this invention “ultra matte” finishes can also -surprisingly- be achieved from a (powder) coating composition comprising a (blocked) isocyanate and a mixture of two polyester polyols. Both polyols have a Tg between 40 and 60ºC prefereably differing not more than 5 to 8ºC, while the OHv of the first polyol is between 150 and 325 and that of the second between 15 and 35.  The ratio between first and second polyol is from about 1:1 to 1:3 w/w. Also surprisingly, the resulting coatings are said to show self-healing properties. An interesting composition but no examples of the polyesters or isocyanates used are given.

Car with matte finish