A method for producing a prepolymer for the production of an integral polyurethane foam is provided. The prepolymer is or can be obtained by reaction of a composition that contains the following components: component A containing a polyoxymethylene-polyoxyalkylene block copolymer having a hydroxyl number of 20 mg KOH/g to 200 mg KOH/g as component Al, component B containing di- and/or polyisocyanates with an NCO content of 15 to 45 wt.-% relative to component B, 0.04 to 1.0 wt.-%, relative to the composition, a proton acid as component C, and optionally a component D that contains auxiliary agents, at a characteristic number of 450 to 850. The invention further relates to the prepolymer obtained by the method, to an integral polyurethane foam based on the prepolymer, and to the use thereof.

Described herein is a process for producing a hydrophilic flexible polyurethane foam. Also described herein is a flexible polyurethane foam obtainable by such a process and a method of using such a flexible polyurethane foam for treating wounds.

A polymer composition may include at least one ethylene vinyl acetate (EVA) polymer; a blowing agent in an amount ranging from 2 to 18 phr; and a crosslinking agent in an amount ranging from 0.3 to 4 phr. A method includes expanding an EVA-based polymer composition to form a foam having a density ranging from 0.01 g/cm3 to 0.06 g/cm3 and a hardness ranging from 10 to 60 Shore 00.

The present invention relates to polyol mixtures comprising (b1) at least one polyether polyol having a hydroxyl value of 10 to 60 mg KOH/g and having a high proportion of ethylene oxide, (b2) at least one polyether polyol having a hydroxyl value of 10 to 100 mg KOH/g, a low proportion of ethylene oxide, and not less than 40% primary OH groups, and (b3) at least one polyether polyol having a hydroxyl value of 10 to 100 mg KOH/g, a low proportion of ethylene oxide, and not more than 30% primary OH groups, and b5) from 0.25 to 10 further parts by weight of polyurea, based on 100 parts by weight of components b1) to b3), optionally present as a constituent of a dispersion polyol based on one or more of components b1) to b3).

The invention further relates to a process for producing flexible polyurethane foams using the mixtures according to the invention, to the thereby obtainable flexible polyurethane foams, and to the use of the thereby obtainable flexible polyurethane foams as a cushioning element for furniture or as a seat element.

An object is to provide a non-red phosphorus type flame retardant composition for polyurethane foam that does not undergo dripping ignition and readily forms a carbonized layer when the polyurethane foam is burned and a flame-retarded polyurethane foam containing the flame retardant composition for polyurethane foam. As a solution, a flame retardant composition for polyurethane foam having high carbonization properties, the flame retardant composition for polyurethane foam containing a phosphorus compound represented by formula (1), is provided.

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(In formula, M is Mg, Al, Ca, Ti, or Zn, and m is 2, 3, or 4.)

This provides an improved process for making a flexible, porous, dissolvable solid sheet article with improved pore structures.

Tertiary amine catalysts having isocyanate reactive groups capable of forming thermally stable covalent bonds able to withstand temperatures from 120° C. and higher and up to 250° C. are disclosed. These catalyst can be used to produce polyurethane foam having the following desirable characteristics: a) very low chemical emissions over a wide range of environmental conditions and isocyanate indexes (e.g., indexes as low as 65 but higher than 60); b) sufficient hydrolytic stability to maintain the catalyst covalently bound to foam without leaching of tertiary amine catalyst when foam is exposed to water or aqueous solutions even at temperatures higher than ambient (temperature range 25° C. to 90° C.); and c) stable contact interface between the polyurethane polymer and other polymers (for example polycarbonate) with minimal migration of tertiary amine catalyst from polyurethane polymer to other polymers yielding no noticeable polymer deterioration at the point of contact even under conditions of heat and humidity.

Flexible polyurethane foams are made by reacting a polyether mixture and water with a polyisocyanate. The foams have excellent suite of properties for use in seating applications, as they are supporting, comfortable and resilient foam. A further advantage is these properties can be obtained at isocyanate indices of close to or even greater than 100.

This invention relates to hybrid polyols useful in the manufacture of polyurethane. The hybrid polyols of the present invention is derived by copolymerizing or grafting a traditional polyester polyol onto a natural oil polyol. In the preferred embodiment of the present invention, the traditional polyester polyol grafted onto natural oil polyol contains a high level of bio-renewable content. The hybrid polyols of the present invention with high level of bio-renewable content is useful in the manufacture of polyurethane either alone or in combination with polyester polyol or polyether polyol derived from petrochemical sources.

A preparation method of a flexible polyurethane foam includes the following steps of: (1) subjecting an epoxidized vegetable oil, a benzoylformic acid, a basic catalyst, and an inert solvent to a ring-opening reaction in a first microchannel reactor of a microchannel reaction device to obtain a vegetable oil polyol; (2) subjecting the vegetable oil polyol obtained in the step (1), a propylene oxide and an inert solvent to an addition polymerization reaction in a second microchannel reactor of the microchannel reaction device to obtain a vegetable oil polyol for flexible polyurethane foam; and (3) using the vegetable oil polyol for flexible polyurethane foam obtained in the step (2) as the unique polyol, and subjecting the same and an isocyanate polyol to a foaming reaction to obtain the flexible polyurethane foam.