Hydrochloric Acid → Propylene glycol methyl ether acetate

Participants

Reaction Steps

54.56 g (70 mol %) of tetraethoxysilane, 9.81 g (14.7 mol %) of methyltriethoxysilane, 7.74 g (5 mol %) of 3-(triethoxysilylpropyl)diallylisocyanurate, 7.42 g (10 mol %) of phenyltrimethoxysilane, 0.31 g (0.3 mol %) of N-(3-triethoxysilylpropyl)-4,5-dihydroimidazole, and 105.03 g of acetone were charged into a 300-mL flask and while stirring the mixture solution with a magnetic stirrer, 24.95 g of a 0.10-mol/L hydrochloric acid was dropped into the mixture solution. After the dropping, the flask was placed into an oil bath controlled to 85° C. and under warming-reflux, the reaction was effected for 240 minutes. Then, the reaction solution was cooled down to room temperature and to the reaction solution, 142 g of propylene glycol monoethyl ether was added. From the resultant reaction mixture, ethanol and methanol, which were reaction by-products, water, and hydrochloric acid were distilled off under reduced pressure and the resultant reaction mixture was concentrated to obtain a hydrolysis-condensation product (polymer) propylene glycol monomethyl ether acetate solution. To the obtained solution, propylene glycol monoethyl ether and propylene glycol monomethyl ether acetate were added to adjust the resultant solution to have a solid residue concentration at 140° C. of 15% by weight while a solvent ratio of propylene glycol monomethyl ether acetate/propylene glycol monoethyl ether became 20/80. The weight average molecular weight of the obtained polymer of Formula (3-7) measured by GPC was Mw 1,500 in terms of polystyrene.

Provenance & Evidence