MQ resins from stable ethylsilicate polymers

• Main Authors: MAGEE WALTER L, JOSLYN WALLACE G, ODNEAL RICHARD S, EMERSON ADAM W
• Format: Patent
• Language: English
• Published: 09.09.2014
• Subjects: ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAININGELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN,SULFUR, SELENIUM OR TELLURIUM; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC CHEMISTRY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; USE OF INORGANIC OR NON-MACROMOLECULAR ORGANIC SUBSTANCES ASCOMPOUNDING INGREDIENTS

An MQ resin including at least 30% SiO2, preferably at least 50 wt % SiO2, and having dynamic viscosity of 50 centipoises (cps) to 750 cps at 25° C. is produced from a stable ethylsilicate polymer. The ethylsilicate polymer includes not greater than 1 wt % of TEOS monomer. The ethylsilicate polymer is produced by a two step addition of catalysts wherein a hydrolysis catalyst, for example, hydrochloric acid is added initially and a second catalyst, such as phosphonitrilic chloride trimer, is added subsequently.