Fiber Reinforced TPU Composites

Patent Title: THERMOPLASTIC POLYURETHANE MATRIX RESIN

 Number/Link: WO 2018/104145

Applicant/Assignee:  Henkel

Publication date: 14 June 2018

Gist”: TPU based on a vicinal alkane diol together with an alkoxylated aromatic diol can be used as matrix material in a fiber composite

Why it is interesting: According to this invention a thermoplastic polyurethane with a high Tg (pref. >80°C) and a high stiffness (>1GPa) can be prepared from a short chain, sterically hindered, vicinal diol (e.g. 1,2-propanediol or 2,3-butanediol), an alkoxylated aromatic diol (e.g. alkoxylated bisphenol A or F) and an aromatic diisocyanate (e.g. 4,4’MDI) pref. mixed with some high functionality isocyanate (e.g. polymeric MDI) to control branching an molecular weight. The TPU composition can be used to make a fiber reinforced composite in an RTM-type process. The cured thermoplastic matrix has high mechanical properties but still allows for post-cure modification of the moulded part.

EtoxBisF

Ethoxylated Bisphenol F

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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)

 

Breathable TPU Membranes

Patent Title: POROUS THERMOPLASTIC MEMBRANES

 Number/Link: WO2017/178482

Applicant/Assignee:  BASF

Publication date: 19-october-2017

Gist”: Semi-permeable membranes are made by phase inversion of all-hardblock TPU solutions

Why it is interesting: ‘Breathable” membranes show a high resistance to liquid water permeation (LEP) combined with a high water vapour permeability (WDD). According to this invention breathable polyurethane membranes can be prepared by dissolving an all-hardblock thermoplastic polyurethane in a polar, aprotic solvent (like N-methyl pyrrolidone) together with a water soluble compound, casting a film and coagulating the film with water. In the examples diisocyanates (MDI, TDI and HDI) are stoichiometrically reacted with chain extenders (MEG, BDO and HDO).  The resulting materials were schredded and dissolved in NMP together with some glycerol. 150 μm thick films were cast on glass and coagulated in water, resulting in membranes with an average pore size ranging between 4 and 500 nm.  The membranes are said to be useful to make breathable fabrics for outdoor wear e.g. (“Gore Tex” (TM) – type materials)

N-methyl-2-pyrrolidone