Aliphatic Polyisocyanurate Composites

Patent Title: METHOD FOR PRODUCING A POLYISOCYANURATE COMPOSITE MATERIAL

 Number/Link: WO 2017/191216  (German)

Applicant/Assignee:  Covestro

Publication date: 9 November 2017

Gist”: Partially trimerized aliphatic diisocyanates are mixed with glass fiber and reacted using a trimerization catalyst

Why it is interesting: Conventional fiber-reinforced composites based on unsaturated polyesters, epoxies, polyurethane and the like are not weather-stable and need to be coated for outdoor use. Weather stable polyisocyanurate composites are known (WO2007/096216 – Huntsman) but are based on aromatic diisocyanates and show high reactivity and short ‘pot life’. According to this invention, PIR composites with improved reaction profile and weatherability can be prepared from partially trimerized aliphatic diisocyanates with a diisocyanate monomer content of less than 20% (w/w). In the examples commercially available HDI and IPDI trimer is used together with short glass fiber and a potassium acetate/PEG 400 blend as catalyst cured at a temperature of 160 to 180°C.

Isophorone diisocyanate (IPDI)

 

SiC-PU Nanocomposites

Patent Title: POLYURETHANE/UREA SILICON CARBIDE NANOCOMPOSITE

 Number/Link: WO2017/027231

Applicant/Assignee: 3M

Publication date: 16-feb-2017

Gist”: Surface modified SiC particles are dispersed in and covalently bound to a polyurethane matrix

Why it is interesting: Silicon carbide (carborundum) particles with an average particle size of about 500 nm are NCO-functionalized by reacting with a surface modfifying agent, e.g 2-triethoxysilylpropylisocyanate. The modified particles are then dispersed and covalently reacted into a polyurethane/polyurea matrix in an amount of 50-55% (w/w) on the composition. The composites can be made into highly erosion resistant films, for use on the outer surface of aircraft.

3-triethoxysilylpropylisocyanate

3-triethoxysilylpropylisocyanate

Polyurethane for Filament Winding

Patent Title: FILAMENT WINDING PROCESSES USING POLYURETHANE RESINS AND SYSTEMS FOR MAKING COMPOSITES

 Number/Link: W2016183073

Applicant/Assignee: Covestro

Publication date: 17-11-2016

Gist”: Compositions comprising polymeric MDI, amine-initated polyethers and natural oil polyols are useful for filament winding

Why it is interesting: Filament winding is a process for the production of hollow composite structures whereby resin-impregnated fibers are wound on a mandrel and then cured. Typically the fibers are impregnated with polyesters or epoxies.  Polyurethane compositions are difficult to use in this process because of reactivity and moisture sensitivity. According to this invention an isocyanate reactive composition comprising at least 50% high functionality amine-initiated polyether polyols and up to 50% of a hydrophobic OH-functional vegetable oil, can be advantageously used for PU filament winding. In the examples blends of 3 and 4-functional amine-initated polyether polyols with mole weight of about 250, castor oil, or OH-functional soy-oil, are used together with a high 2,4′ polymeric MDI.

Filanent winding process

Filanent winding process

Non-Isocyanate Polyurethanes from Sucrose-Fatty Acid Esters

Patent Title: BIOBASED CYCLIC CARBONATE FUNCTIONAL RESINS AND POLYURETHANE THERMOSETS THEREFROM

 Number/Link: US2016/0312060

Applicant/Assignee: NDSU

Publication date: 27-10-2016

Gist”: Epoxidized sucrose-fatty acid esters are reacted with CO2, then with polyamines

Why it is interesting:  Esters of unsaturated fatty acids and sucrose have been known since the 1960s and are useful in e.g. coatings.  Highly subsituted sucrose esters with an average of 7.7 fatty acid chains per molecule, a molecular weight of about 2400 and a relatively low viscosity of 300-400 mPa.s are commercially available. According to this invention, epoxidized sucrose-fatty acid esters can be further reacted with carbon dioxide resulting in a resin with a ‘pluraility’ of cyclocarbonate groups. Curing with polyamines results in highly crosslinked poly(hydroxyurethanes) useful for coatings, composites and adhesives.

Epoxidized sucrose-fatty acid ester

Epoxidized sucrose-fatty acid ester

 

 

Carbon-Black Reinforced Polyurethane Tires

Patent Title: TIRE WITH CARBON BLACK REINFORCED POLYURETHANE 

 Number/Link: US20160060420

Applicant/Assignee: Goodyear

Publication date: 3-03-2016

Gist”: Dried, pulverized C-black is used in cast elastomer

Why it is interesting: According to this invention cast polyurethanes with properties useful for tire production can be made by incorporating 2-4% (w/w) of carbon black, pulverized to an average particle size of 5-10 μm. The carbon black is dispersed in the polyol component together with molecular sieves to absorb the water inherently present in carbon black.  It is said that removing the water allows the carbon black to react with an excess of isocyanate present, thereby greatly improving its reinforcing characteristics. Although not mentioned in the text I assume that the tires are intended for low-speed vehicles only.

GoodYear Tire

GoodYear Tire