A method for the synthesis of an auxetic polyurethane foam with a defined cell structure and an auxetic polyurethane foam substrate obtainable by a method according to the invention. The method includes mixing a polyol reagent and a foaming reagent, forming a reaction mixture, mixing an isocyanate with the reaction mixture, compressing and/or contracting the isocyanate/reaction mixture, and allowing the compressed and/or contracted isocyanate/reaction mixture to cure.

Disclosed is a thermoset, thermal insulating foams having desirable and unexpectedly low thermal conductivity, and to compositions, method and systems which use and/or are used to make such foams comprising: (a) providing thermosetting foam forming component and a blowing agent for forming predominantly closed cells in the foam, wherein the blowing agent comprises: (i) cis-1,1,1,4,4,4-hexafluoro-2-butene (HFO-1336mzzm(Z)) and cyclopentane, with the HFO-1336mzzm(Z) and cyclopentane in the blowing agent together comprising at least about 50% by weight of the total of all components in the blowing agent and (ii) the weight ratio of HFO-1336mzzm(Z) to cyclopentane in the blowing agent is from about 45:55 to less than 68:32 and (b) forming foam from said provided foamable composition.

An absorbent wound dressing comprises a hydrophilic porous substrate and polymer-stabilized silver nanoparticles distributed throughout the porous substrate. The silver nanoparticles have a particle size d.sub.50 in the range of about 45 nm to about 85 nm and the silver nanoparticles are present in the substrate in an amount of about 0.16% to about 1.5% by weight of the total weight of the substrate. The wound dressing produces a 7-day log reduction of 4 or more for bacteria in accordance with the Modified AATCC Test Method 100. The wound dressing is also non-cytotoxic in accordance with ISO 10993-5 standard procedure for medical device cytotoxicity assessment.

The present invention relates to a method for preparing an aqueous polyurethane (PU) dispersion with non-ionic reactive emulsifiers and sulfonate groups. The aqueous PU dispersion includes the following components: 10-40 parts by weight of polymer polyol, 5-20 parts by weight of isocyanate monomer, 0.1-1.5 parts by weight of trimethylolpropane, 3-15 parts by weight of monofunctional alkoxy polyethylene glycol or propylene glycol, 0.5-2.0 parts by weight of diaminosulphonate chain extender, 0.5-3.0 parts by weight of non-ionic organic amine chain extender, 0.01-0.05 parts by weight of catalyst, 0-8 parts by weight of organic solvent, 50-80 parts by weight of deionized water, and 0.1-5 parts by weight of thickener. In the presence of non-ionic reactive emulsifiers, introduction of sulfonate groups at late chain extension stage of the aqueous PU dispersion obtain stable large-size polymer particles. A coating film thereof has a 60° gloss of <1.0; the emulsion has excellent storage stability and redispersibility.

A process for recycling a polyurethane material wherein the polyurethane material comprises a moiety that is capable of undergoing decomposition through acidolysis, the process comprising: contacting the polyurethane material with an acid solution and allowing at least a portion of the polyurethane material to decompose into a recovered raw material composition comprising a degradation compound; and introducing an acetoacetylated polyol into the recovered raw material composition and reacting the acetoacetylated polyol with the degradation compound to form a polyol compound.

Polyurethane foam-forming compositions, methods of producing polyurethane foams, polyurethane foams produced from such compositions made by such methods, as well as isocyanate-reactive compositions. The polyurethane foam-forming compositions include a polyol blend, a blowing agent composition, and a polyisocyanate. The polyol blend includes an aromatic amine-initiated polyether polyol, a saccharide-initiated polyether polyol, and an aromatic polyester polyol and has a content of —C.sub.2H.sub.4O— units of 3 to 6% by weight, based on the total weight of the polyurethane foam-forming composition. The blowing agent composition includes a hydrochlorofluoroolefin and a carbon dioxide-generating chemical blowing agent.

A process is provided for forming a foam product integral with a cover surface, which restricts emission of the carbon oxide during the step of preparing a carbon-oxide-mixed liquid by mixing carbon oxide into a first material containing polyol as a primary ingredient; under a pressure applied thereto. The process includes a first step wherein a carbon-oxide-mixed liquid material is prepared by mixing carbon oxide C into a first material containing polyol as a primary ingredient, under a pressure applied thereto, without effecting a forced stirring during said first step; a second step wherein said carbon-oxide-mixed liquid material and a second material containing isocyanate as a primary ingredient are impinged on and mixed with each other in a high-pressure foaming agent preparation device, thereby providing a resultant urethane material as a liquid urethane foaming agent; and a third step wherein said liquid urethane foaming agent produced at said second step is introduced toward an inside of a surface cover element under a pressure applied thereto.

The present invention relates to a process for the treatment of thermoplastic polyurethane, to the treated thermoplastic polyurethane and to the use thereof.

A process is described for producing PU foams, especially rigid PU foams, based on foamable reaction mixtures containing polyisocyanates, compounds having reactive hydrogen atoms, blowing agents, foam stabilizers, and possibly further additives, wherein specific perfluoropolyethers are additionally used.

A flexible cellular foam or fabric product is coated with a coating including highly thermally conductive nanomaterials. The highly thermally conductive nanomaterials may be carbon nanomaterials, metallic, or non-metallic solids. The carbon nanomaterials may include, but are not necessarily limited to, carbon nanotubes and graphene nanoplatelets. The highly thermally conductive nanomaterials may include but are not limited to nano-sized solids that may include graphite flakes, for example. When coated on a surface of flexible foam, the presence of nanomaterials may impart greater thermal effusivity, greater thermal conductivity, and/or a combination of these improvements. The flexible foam product may be polyurethane foam, latex foam, polyether polyurethane foam, viscoelastic foam, high resilient foam, polyester polyurethane foam, foamed polyethylene, foamed polypropylene, expanded polystyrene, foamed silicone, melamine foam, among others.