Patent ID: 6433059
Filing Date: 2002-08-13
Classification: B29C,C08G,C08L,Y10S

Abstract:
A method for preparing a binder material for cellulosic products comprising:a) providing a polymeric resin base material comprising 4,4â€² or 2,4â€² methylene diphenylene diisocyanate in the range of from about 20% to about 55% by weight and an isocyanate functionality greater than 2, wherein said polymeric base resin material contains isocyanate polymeric by-products obtained as a result of the manufacture of MDI and incorporates oligomers of the diisocyanate; b) forming a colloidal silica from silica and a basic solution; c) incorporating the colloidal silica into said polymeric base material at a temperature, rate of addition and agitation level to achieve a substantially homogeneous cellulosic binder material.