Low temperature stable polymethylene polyphenylene polyisocyanates
申请人:BASF Corporation
公开号:EP0189156A2
公开(公告)日:1986-07-30
Low temperature stable polymethylene polyphenylene polyisocyanates are composed of crude polymethylene polyphenylene polyisocyanate containing from about 50 to about 80 percent by weight 2-ring diphenylmethane diisocyanate wherein from about 65 to about 93 weight percent of the 2-ring diisocyanate is 4,4'- and from about 7 to about 35 weight percent is 2,4'- and furthermore the composition contains from about 1 to about 5 weight percent carbodiimide- uretonimine structure. The polyisocyanates are useful in preparing polyurethane foams.
Stable 4,4'-diphenylmethane diisocyanates are composed of 4,4'-diphenylmethane diisocyanates containing from about 2 to about 10 weight percent carbodiimide-uretonimine structure. The diisocyanates are useful in preparing polyurethane foams.
Liquid carbodiimide-uretonimine-modified polyphenylene polyisocyanates and polyurethane foams made therefrom
申请人:BASF Corporation
公开号:EP0308710A1
公开(公告)日:1989-03-29
A process for the preparation of liquid polymethylene polyphenylene polyisocyanate blends containing carbodiimide-uretonimine isocyanate linkages, containing a high two-ring methylene bis(phenylisocyanate) content, and light colored polyurethane foams made therefrom. The process is comprised of reacting polymethylene polyphenylene polyisocyanate with a catalytically effective amount of a carbodiimide-uretonimine promoting compound at a temperature sufficient to promote the formation of carbodiimide-uretonimine linkages and an isocyanate content of about 25 percent and the desired viscosity is reached, and then reacting that product to deactivate the carbodiimide-uretonimine catalyst, and finally blending two ring methylene bis(phenylisocyanate) with the product to produce a mixture having a two ring isocyanate content of about 60 percent of the total ring content and a viscosity comparable to standard polymeric MDI. Urethane foams made from this material are lighter in color than those formed from standard polymeric MDI.
The present invention provides a liquid methylene bis(phenylisocyanate) composition including a high concentration of methylene bis(phenylisocyanate) which has an improved storage stability. The invention further provides a method of making the liquid methylene bis(phenylisocyanate) compositions of the present invention.
Process for the production of carboiimide modified organic isocyanates
申请人:Bayer MaterialScience LLC
公开号:EP1607425A1
公开(公告)日:2005-12-21
The present invention relates to an improved process for the production of carbodiimide modified organic isocyanate, preferably a polymethylene polyphenylisocyanate, and most preferably diphenylmethane diisocyanate. This process includes (1) neutralizing acidic impurities in an organic isocyanate, (2) partially carbodiimidizing isocyanate groups of the neutralized organic isocyanate, and (3) terminating the carbodiimidization reaction.