Imperial Chemical Industries Limited

Tu Pham

Louis Muller

Gabriel Verhelst

Alain Parfondry

Mireille B De Witte

Arun Watts

A method for the preparation of flexible polymeric foam by reacting a polyisocyanate component with an isocyanate-reactive component comprising at least 50% by weight of water, the polyisocyanate component comprising at least two polyisocyanate compositions, one of them being a low NCO isocyanate terminated prepolymer and the second being a high NCO polyisocyanate.

Manufacture of polymeric foams

The invention relates to a liquid isocyanate-containing prepolymer composition having an average isocyanate functionality greater than 2 and an NCO content of from 2 to 15% by weight, as obtainable by reacting an isocyanate reactive polymer having an average nominal functionality of from 2 to 6 with a stoichiometric excess of a diphenylmethane diisocyanate composition containing at least 2% by weight of 2,4'-diphenylmethane diisocyanate and having an average isocyanate functionality in the range from 2 to 2.3. The invention also relates to a method for preparing a polyurethane foam, which comprises reacting such a prepolymer composition with water.

Isocyanate composition and process for making flexible foams therefrom

Substantially water blown flexible polyurethane foams, based on methylene diphenyl isocyanates, having a density ranging from 15-45 kg/m.sup.3. Such foams may be obtained through a process substantially avoiding halocarbon blowing agents, which comprises reacting methylene diphenyl isocyanates with water and one or more isocyanate-reactive compounds selected from polyols and polyamines with a functionality of 2-4 and an average equivalent weight ranging from 750-5000, while the isocyanate index ranges from 10 to 60, and weight ratio of the isocyanate-reactive compound(s) to water is less than 20.

Manufacture of polyurethane foam

Flexible polyurethane foam based on methylene diphenyl isocyanates and isocyanate-reactive compounds selected from polyols and polyamines, for which the ratio of the density expressed in kg/m.sup.3 to the compression hardness at 40% compression, expressed in kPa, has a value of at least 20. Such foams may be obtained through a process which comprises reacting methylene diphenyl isocyanates with one or more isocyanate-reactive compounds selected from polyols and polyamines with a functionality of 2-4 and an average equivalent weight ranging from 750-5000 and from 0 to 5 parts by weight of water per 100 parts of polyols and/or polyamine, optionally together with additives conventional in the art, and optionally together with blowing agents other than water, whereas the isocyanate index ranges from 10 to 60.

Growing community of inventors

Grez Doiceau, Belgium

Tu Pham