A transurethane polycondensation pathway has been used to produce acrylate terminated Non-Isocyanate PolyUrethane (NIPUA) oligomers (A-Ol) with controlled molecular weights and chemical structures. These compounds were then photo-crosslinked under UV radiations to afford several NIPU acrylate coatings. The influence of the content in urethane functions as well as the chemical structures on the thermal
METHOD FOR TREATMENT OF ISOCYANATE RESIDUE, AND METHOD FOR TREATMENT OF CARBONATE
申请人:Shimokawatoko Yoshiki
公开号:US20120271067A1
公开(公告)日:2012-10-25
A method for treating an isocyanate residue, which comprises carrying out a thermal decomposition reaction of a carbamate that is produced by the reaction among an amine, urea and/or an N-unsubstituted carbamic acid ester and an alcohol to produce a decomposition solution, separating an isocyanate and the alcohol from the decomposition solution to produce the isocyanate residue, and bringing the isocyanate residue into contact with high-pressure/high-temperature water to decompose the isocyanate residue into an amine; and a method for treating a carbonate, which comprises bringing the carbonate into contact with high-pressure/high-temperature water to decompose the carbonate into an alcohol.
申请人:UNIVERSITY-INDUSTRY COOPERATION GROUP OF KYUNG HEE UNIVERSITY
公开号:US20140303399A1
公开(公告)日:2014-10-09
The present invention relates to a method for preparing an aliphatic diisocyanate by pyrolyzing an aliphatic dicarbamate in liquid phase, using a tin (II) or (IV) compound as a catalyst and a zwitterionic compound as a stabilizer, thereby remarkably inhibiting high-boiling by-products and providing the aliphatic diisocyanate with high yield.
A process for preparing diisocyanate compounds by the i following two-step reaction without using phosgene. In the first step, a diamine and dimethyl carbonate are reacted with each other in the presence of an alkali catalyst to synthesize a corresponding urethane compound and, in the second step, the urethane compound is thermally decomposed in a high-boiling solvent under a reduced pressure of 1 to 700 Torr in the presence of a catalyst composed of a simple substance of metal selected from among manganese, molybdenum, tungsten, zinc, and beryllium or a compound thereof to obtain a corresponding diisocyanate compound.
Provided is a process for producing isocyanates from carbamic acid esters which comprises thermally decomposing carbamic acid esters in the presence of a catalyst containing at least one compound selected from the group consisting of organic sulfonic acids and alkaline metal salts of organic sulfonic acids. Thereby, a high thermal decomposition rate can be provided and isocyanate can be obtained in a high yield.