Homogeneous hydrolysis of 4,4’-methylenediphenyl diisocyanate (MDI) in water
نویسندگان
چکیده
The environmental effects of 4,4’-methylenediphenyl diisocyanate (MDI) are linked with its potential hydrolytic conversion to 4,4’-methylenedianiline (MDA). Likewise, the reactions MDI biological macromolecules govern absorption, distribution, metabolism, and excretion processes associated sensitization toxicological effects, formation MDA in body would be a source additional concern. To obtain better insight into influence reactive behavior on health hazards, hydrolysis water was studied at very high dilution (120 nmol/L) under homogeneous conditions that minimized interference by solvents, buffers, strong N- or S-centered nucleophiles. reaction proceeds two distinct steps, converting one isocyanate group time. Pseudo-first-order rate constants for were determined 293 K pH values between 4 9, temperatures 283 303 7. half-life neutral 298 found 11 s. This newly-generated kinetic mechanistic information provides basis refining conceptual quantitative models used predict MDI-related substances.
منابع مشابه
4,4'-Methylenediphenyl diisocyanate and polymeric 4,4'-methylenediphenyl diisocyanate.
1.1 Chemical and physical data 1.1.1 Nomenclature Chem. Abstr. Serv. Reg. No.: (a) 101-68-8 (monomer) and (b) 26447-40-5 Chem. Abstr. Name: 1,1′-Methylenebis(4-isocyanatobenzene) IUPAC Systematic Names: For 101-68-8: isocyanic acid, methylenedi-paraphenylene ester Synonyms: Bis(1,4-isocyanatophenyl)methane; diphenylmethane diisocyanate; MDI; methylenedi-para-phenylene isocyanate and for 26447-4...
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ژورنال
عنوان ژورنال: Toxicological & Environmental Chemistry
سال: 2021
ISSN: ['0092-9867', '1026-7832', '1029-0486', '0277-2248']
DOI: https://doi.org/10.1080/02772248.2021.2009480