24801-88-5Relevant articles and documents
Formation and Depolymerization of Oligomers during Thermal Cracking of Silicon-Containing Carbamates
Wang, Peixue,Zhou, Dawei,Fei, Yuqing,Long, Yan,Deng, Youquan
, p. 1039 - 1045 (2019)
Polymerization reactions in the thermal cracking of N-substituted carbamates to produce the corresponding isocyanates significantly reduce the yield of isocyanates and thus vastly hinder the industrial application of such non-phosgene routes. Herein, we tried to recycle the oligomers generated during the thermal cracking of 3-ethylcarbamatopropyltriethoxysilane (CPTS) to produce 3-isocyanatopropyltriethoxysilane (IPTS). Firstly, the polymerized substrates of the pyrolysis reaction were analyzed by NMR, IR, MALDI-TOF-MS and TG, indicating the pyrolysis substrates were mixtures of CPTS (25 wt%), polyureas (74 wt%), imines, and other compounds (a carbonyl group source, but also forms hydrogen bonds with polyureas. In addition, NH3 co-produced can also modify the reaction system microenvironment, which might be favorable for the dissociation of polyureas. With optimized conditions, more than 96 % of polymerized substrates could be reverted to CPTS for secondary cracking.
Preparation method of 3-isocyanate propyltriethoxysilane
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Paragraph 0033-0058, (2019/11/21)
The invention relates to a preparation method of 3-isocyanate propyltriethoxysilane, belonging to the field of fine chemical synthesis. The method comprises synthesizing the 3-isocyanate propyltriethoxysilane from chloropropyltriethoxysilane and potassium cyanate through one-step synthesis in an ionic liquid adopted as a solvent under a catalysis function. An isocyanate process is adopted, and aiming at disadvantages, of the process, that reaction raw materials are difficult to dissolve and yields are low, the preparation method of the 3-isocyanate propyltriethoxysilane based on the ionic liquid is provided.
Preparation method of 3-isocyanatopropyltrialkoxysilane
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Paragraph 0018; 0020, (2019/03/25)
A preparation method of 3-isocyanatopropyltrialkoxysilane comprises the steps of (1) mixing 3-chloropropyltrialkoxysilane, urea and ammonium salt, heating to 120-130 DEG C, stirring to allow reactingfor 2-3 hours, cooling, and removing solid by centrifuging or filtering; (2) adding the separated liquid into a manganese or cobalt carboxylate catalyst, heating to 150-200 DEG C under nitrogen protection, and stirring to allow reacting for 1-2 hours; (3) sampling the reaction product, rectifying under reduced pressure after qualification is confirmed by detection, and separating the target product. The preparation method has the advantage of evidently reduced production cost.