Polymeric 4,4-diphenyl methane diisocyanate

A polyurethane adhesive is produced by reacting together two basic raw materials - a polyol and an isocyanate (see Step polymerization). The two most common polyols are based on polyether and polyester, and the two principal isocyanates used are toluene diisocyanate (TDI) and diphenyl methane diisocyanate (MDI), both of these latter products being extremely reactive. 

The early acute pulmonary response of Mstar rats exposed nose-only to respirable polymeric diphenyl-methane 4,4 -diisocyanate aerosol for 6 h were bronchoalveolar lavage cells markedly loaded with phosphatidylcholine (Pauluhn 2000). Bronchoalveolar lavage cells from rats repeatedly exposed to 12.9 mg polymeric diphenyl-methane 4,4 -diisocyanate m" air (6 h/day, 5 days/week for 14 days exposure was from days 0-17 followed by a post-exposure period to day 35) increased in number and phospholipid content significantly in a time-dependent marmer and returned to almost... 

F. G. Hutchinson, R. G. C. Henbest, and M. K. Leggett, Polymeric Shaped Articles, U.S. Pat. 4,062,826 (1977). SIN s, grafted. Plastic polyurethanes based on 4 4 -diphenyl-methane diisocyanate. Styrene-unsaturated polyester. Gel polymerization. Shaping of partly gel-polymerized articles. 

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