Damping silicon rubber with relatively small temperature effect and preparation method thereof

Abstract

The invention relates to damping silicon rubber with a relatively small temperature effect and a preparation method thereof. The crude rubber of the damping silicon rubber is characterized in that a main chain of the crude rubber of the silicon rubber consists of methyl phenyl silicone chain elements, diethyl silicone chain elements, dimethyl silicone chain elements and methyl ethylene silicone chain elements with different content; the molecular weight of the crude rubber is more than 400 thousands; the crude rubber is prepared by copolymerizing methyl phenyl cyclosiloxane, diethyl cyclosiloxane, dimethyl cyclosiloxane and methyl ethylene cyclosiloxane in the presence of initiators of polypropylene oxide and the like. The crude rubber with the structure has good damping property in a relatively wide temperature range after being vulcanized, the dynamic loss factor and the modulus hardly change along with temperature changes, and the damping silicon rubber belongs to the field of organic silicon high polymer.

Description

technical field

[0001] The invention belongs to the field of silicone rubber preparation, in particular to a damping silicone rubber with small temperature effect and a preparation method thereof. Background technique

[0002] Silicone rubber is a rubber material with -Si-O- chain link as the main chain, which has excellent high and low temperature resistance, and stable mechanical properties in a wide temperature range and wide frequency. Silicone rubber can be widely used as a damping material in aerospace and other fields, making up for the shortcomings of conventional damping and shock-absorbing materials with a narrow temperature range. However, the damping factor of ordinary silicone rubber is small (generally 0.05-0.1), or the damping factor and dynamic modulus vary greatly with temperature, so it is difficult to meet the requirements of high damping stability applications.

[0003] Chinese patent CN102181056A discloses a method for preparing damping silicone rubber,...

Examples

Embodiment 1

[0037] Example 1: Add 18.6g of tetramethyldivinyldisiloxane and 2g of sodium hydroxide powder into a pressure-resistant reactor, add 15ml of anhydrous toluene and 2g of polypropylene oxide with a molecular weight of 1000, seal the reactor, and raise the temperature React at 100°C for 1 hour, cool down to -5°C, press in 1.15g of sodium wire, gradually raise the temperature to 80°C, continue to react for 1hr, then add 40.8g of methylphenylcyclosiloxane and 45.9g of hexaethylcyclotri The mixture of siloxanes was reacted at 100°C for 2 hours, continued to heat up to 120°C to evaporate the toluene and reacted for 1 hour, and cooled to room temperature to obtain a sodium hydroxide silicon alkoxide initiator.

Embodiment 2

[0038] Embodiment 2: 9.3g of tetramethyldivinyldisiloxane and 1.425g of calcium hydroxide powder are added to a pressure-resistant reactor, 15ml of anhydrous toluene and 2g of polypropylene oxide with a molecular weight of 1000 are added, and the reactor is closed. Raise the temperature to 150°C for 1 hour, cool to -5°C, press in 1g of calcium wire, gradually raise the temperature to 80°C, continue the reaction for 1hr, then add 20.4g of methylphenylcyclosiloxane and 23g of hexaethylcyclotrisilane The mixture of oxanes was reacted at 100°C for 2hrs, continued to heat up to 120°C to evaporate toluene and reacted for 1hr, and then cooled down to room temperature to obtain calcium hydroxide silicon alkoxide initiator.

Embodiment 3

[0039] Example 3: As a comparison, a conventional method was used to prepare sodium hydroxide silicon alkoxide, 4g of sodium hydroxide powder was added to the reactor, 10.2g of methylphenylcyclosiloxane and 11.95g of hexaethylcyclotrisiloxane were added The mixture was heated up to 100°C for 1 hr, then added a mixture of 30.6 g of methylphenylcyclosiloxane and 35.85 g of hexaethylcyclotrisiloxane, reacted at 100°C for 2 hr, and continued to heat up to 120°C for 1 hr. Cool down to room temperature to obtain sodium hydroxide silicon alkoxide initiator.

technical field

[0001] The invention belongs to the field of silicone rubber preparation, in particular to a damping silicone rubber with small temperature effect and a preparation method thereof. Background technique

[0002] Silicone rubber is a rubber material with -Si-O- chain link as the main chain, which has excellent high and low temperature resistance, and stable mechanical properties in a wide temperature range and wide frequency. Silicone rubber can be widely used as a damping material in aerospace and other fields, making up for the shortcomings of conventional damping and shock-absorbing materials with a narrow temperature range. However, the damping factor of ordinary silicone rubber is small (generally 0.05-0.1), or the damping factor and dynamic modulus vary greatly with temperature, so it is difficult to meet the requirements of high damping stability applications.

[0003] Chinese patent CN102181056A discloses a method for preparing damping silicone rubber,...

Examples

Embodiment 1

[0037] Example 1: Add 18.6g of tetramethyldivinyldisiloxane and 2g of sodium hydroxide powder into a pressure-resistant reactor, add 15ml of anhydrous toluene and 2g of polypropylene oxide with a molecular weight of 1000, seal the reactor, and raise the temperature React at 100°C for 1 hour, cool down to -5°C, press in 1.15g of sodium wire, gradually raise the temperature to 80°C, continue to react for 1hr, then add 40.8g of methylphenylcyclosiloxane and 45.9g of hexaethylcyclotri The mixture of siloxanes was reacted at 100°C for 2 hours, continued to heat up to 120°C to evaporate the toluene and reacted for 1 hour, and cooled to room temperature to obtain a sodium hydroxide silicon alkoxide initiator.

Embodiment 2

[0038] Embodiment 2: 9.3g of tetramethyldivinyldisiloxane and 1.425g of calcium hydroxide powder are added to a pressure-resistant reactor, 15ml of anhydrous toluene and 2g of polypropylene oxide with a molecular weight of 1000 are added, and the reactor is closed. Raise the temperature to 150°C for 1 hour, cool to -5°C, press in 1g of calcium wire, gradually raise the temperature to 80°C, continue the reaction for 1hr, then add 20.4g of methylphenylcyclosiloxane and 23g of hexaethylcyclotrisilane The mixture of oxanes was reacted at 100°C for 2hrs, continued to heat up to 120°C to evaporate toluene and reacted for 1hr, and then cooled down to room temperature to obtain calcium hydroxide silicon alkoxide initiator.

Embodiment 3

[0039] Example 3: As a comparison, a conventional method was used to prepare sodium hydroxide silicon alkoxide, 4g of sodium hydroxide powder was added to the reactor, 10.2g of methylphenylcyclosiloxane and 11.95g of hexaethylcyclotrisiloxane were added The mixture was heated up to 100°C for 1 hr, then added a mixture of 30.6 g of methylphenylcyclosiloxane and 35.85 g of hexaethylcyclotrisiloxane, reacted at 100°C for 2 hr, and continued to heat up to 120°C for 1 hr. Cool down to room temperature to obtain sodium hydroxide silicon alkoxide initiator.

Images