One of the most important reactions of organosilicon, hydrosilylation (TWO)
Hits: 741
img
The hydrosilylation reaction mainly includes compounds containing carbon-carbon double bonds, compounds containing silicon-hydrogen bonds, and platinum catalysts, all of which are indispensable. Among them, the compound containing a carbon-carbon double bond can be a small organic molecule with a carbon-carbon double bond, or a small silicone molecule or a silicone polymer with a carbon-carbon double bond, such as vinyl silicone oil, vinyl silicone rubber And vinyl silicone resins, etc.; compounds containing silicon-hydrogen bonds, mainly including small silicone molecules containing silicon-hydrogen bonds and silicone polymers such as hydrogen-containing silicone oil, hydrogen-containing silicone resin, and hydrogen-containing silicone rubber; platinum catalysts, currently The most widely used catalyst is Karstedt's catalyst diluted with a specific diluent. The main component is a complex of platinum and vinyl with double heads. It has high catalytic activity and fast reaction speed, but it is also easy to be poisoned. The disadvantage of deactivation, so in the process of packaging, transportation and use, it is necessary to prevent platinum catalyst from contacting organic matter containing nitrogen, phosphorus, sulfur and other elements and ionic compounds containing heavy metals such as tin, lead, mercury, bismuth, and arsenic. It is easy to poison the platinum catalyst and become invalid.
The hydrosilylation reaction can also occur at room temperature, and the reaction speed is extremely fast after heating, and a large amount of heat will be released along with the reaction process. Therefore, when using this reaction for industrial production, attention should be paid to the order of ingredients, and the ratio of each component in the formula should also be controlled within a reasonable range to prevent affecting product performance or accidents. Usually, in addition to the three components of the compound containing carbon-carbon double bond, compound containing silicon-hydrogen bond and platinum catalyst, a small amount of polymerization inhibitor is added in the hydrosilylation reaction. The main function of the polymerization inhibitor is Suppress the reaction rate of the hydrosilylation reaction at room temperature, but under heating conditions, the polymerization inhibitor has very little effect on the reaction rate of the hydrosilylation reaction.
After understanding the various components and application areas of the hydrosilylation reaction, the specific products used in the hydrosilylation reaction can be improved by selecting raw materials with different indicators, designing different formulas, and adding various types of additives. The performance of the product can be controlled by selecting platinum catalysts with different activities and changing the amount of platinum catalyst added to control the reaction speed, improve production efficiency, and finally make products with excellent performance.