| 摘要 |
<p>#CMT# #/CMT# Preparing silicone resin having a weight average molecular weight of at least 5000 g/mole and a polydispersity of not > 65, comprises (i) hydrolyzing and condensing (a) a silicon-bonded and alkoxy groups carrying silicone resin intermediate or a silicon-bonded and alkoxy- and hydroxy groups carrying silicone resin intermediate or their mixtures, with (c) a basic or acidic catalyst that provides alkalinity or acidity to the mixture, (d) water, and (e) an aliphatic carboxylic acid ester as a solvent, (ii) distilling obtained alcohol from the reaction mixture, and (iii) inactivating the catalyst. #CMT# : #/CMT# Preparing silicone resin having a weight average molecular weight of at least 5000 g/mole and a polydispersity of not > 65, comprises (i) hydrolyzing and condensing (a) a silicon-bonded and alkoxy groups carrying silicone resin intermediate or a silicon-bonded and alkoxy- and hydroxy groups carrying silicone resin intermediate or their mixtures, with (c) a basic or acidic catalyst that provides alkalinity or acidity to the mixture, or its mixtures, which do not completely neutralize each other, (d) water, and (e) an aliphatic carboxylic acid ester as a solvent, (ii) distilling obtained alcohol from the reaction mixture, and (iii) inactivating the catalyst by thermally treating or by neutralizing with the addition of an equivalent amount of an acid or a base, where a portion of the solvent for adjusting the viscosity, and solution of the forming silicone resin is allowed to remain in the final product. #CMT#USE : #/CMT# The silicone resin is useful for forming film. #CMT#ADVANTAGE : #/CMT# The silicone resin exhibits high molecular weight, does not make use of aromatic solvents and does not undergo gelling, and are storage stable. #CMT#INORGANIC CHEMISTRY : #/CMT# Preferred Method: The reaction is additionally carried out with (b) alkoxy-functional silane, its mixtures or mixture of alkoxy-functional silane with its hydrolysis- and/or condensation products. #CMT#ORGANIC CHEMISTRY : #/CMT# Preferred Components: The component (c) is a quaternary ammonium- and/or phosphonium compound. The aliphatic carboxylic acid ester is of formula (R8-C(=O)OR9) (I). R8 : monovalent 1-30C alkyl (optionally branched and non-adjacent C are optionally replaced by O), 1-30C alkenyl or H; and R9 : monovalent 1-30C alkyl (optionally branched and non-adjacent C are optionally replaced by O) or 1-30C alkenyl. #CMT#EXAMPLE : #/CMT# 460 g Silicone resin intermediate exhibiting a weight average molecular weight of 1800 g/mole and a polydispersity of 2, was dissolved in 127.5 g methoxypropyl acetate. Then 40 g deionized water and 2.37 g benzyltrimethylammonium hydroxide in methanol was added to the obtained mixture. Then the mixture was heated to 80[deg] C and then stirred at this temperature for 2 hours. Then the mixture was worked up to obtain the silicone resin having a weight average molecular weight of 30300 g/mole, a number average molecular weight of 2800, and a polydispersity of 10.6.</p> |
