Nano-silica is the best filler for reinforcing high-temperature vulcanized silicone rubber. The nano-silica aggregates have a good reinforcing effect on the silicone rubber. After the nano-silica powder is added to the rubber, a microcrystalline region with silica as a crystal nucleus is formed, which increases the physical cross-linking point and is more prone to occur. Crystallization, the tensile strength of vulcanizate can be increased from 0.35MPa to 14MPa, the strength of rubber can be increased by 40 times, far higher than the reinforcement rate (1.4-10 times) that other rubber can achieve.

Technical indicators：

Application characteristics of nano silica in rubber:

As a reinforcing agent and anti-aging agent, nano-silica is used in rubber products to improve the strength of rubber products, improve toughness, anti-aging, anti-friction ignition, and extend life.

Nano-silica is a very effective reinforcing filler for RTV silicone rubber, which can significantly increase its strength. On the one hand, it is due to the small size effect of nano-sized dioxide particles and a large specific surface area; on the other hand, because the surface contains many silicon light-based groups, the particles can form a network structure through the interaction of hydrogen bonds and van der Waals forces, while silica The particles also interact strongly with the silicone molecules, improving the interface. The reinforcing effect of nano-silica on silicone rubber is affected by its particle size, specific surface area and structure. Generally, the smaller the particle size, the larger the specific surface area, the higher the structure, the better the reinforcing effect, and the vulcanized rubber. The higher the strength and hardness.

Add amount:

Silicone rubber: 3.0-30%; polysulfide rubber: 0.1-5%;

Polyurethane: 3.0-25%; Acrylates: 0.5-3.5%

Instructions:

According to the formula ratio, the raw rubber, hydroxy silicone oil and nano-silica are kneaded uniformly on the double-roll rubber mixer, and the rubber mixture is thinly passed through the sheet. After heat treatment at 170 ° C for 2 hours, the refining and vulcanizing agent is added, and the thin film is discharged. The next day, it was molded on a vulcanizer. The vulcanization conditions were 175 ° C × t90. T90 is a positive vulcanization time of the vulcanizate measured by an LH-90 vulcanizer.

When adding nanosilica to rubber, attention must be paid to its degree of dispersion in the polymer. The degree of dispersion of nano-silica in the system has a great influence on the properties of rubber. In the transparent compound system, the higher the transparency, the better the dispersion of nano-silica.