As far as I know, rubber blends are solid silicone rubber. Typically, it is a single component adhesive, with cross-linking agents, catalysts, and inhibitors mixed with the adhesive. Mixtures are generally extruded and vulcanized at high temperature, unlike liquid rubbers, which are mostly two-component and have three types of vulcanization: room temperature vulcanization, low temperature vulcanization, and high temperature vulcanization.

 Production process:
"After kneading raw silicone rubber, white carbon black, and other fillers in a kneader, a crosslinking agent, catalyst, inhibitor, and various pigments are added to a two-roller rubber mixer to obtain the mixture.". The resulting rubber compound is called silicone rubber compound.

Physical properties/performance:

1. Before vulcanization (curing), it is "solid", and the color depends on the color added during mixing. If it is not added, it is white, with a plasticity value of about 200~300;
2. After vulcanization, the transparency without adding color is not as good as that of liquid rubber, and the "light transmittance" is not higher than 70%. The "rebound value" of rubber blends with the same "hardness" is generally lower than that of liquid rubber, but the "mechanical properties" are generally higher than that of liquid rubber. The "tensile strength" reaches 10-20MPa, the "tear resistance strength" reaches 40-60KN/m, and the "elongation" is generally better than that of liquid rubber with the same hardness. The "curing temperature" is generally between 140 and 180 degrees. "Linear shrinkage" I won't say it anymore.

 Chemical properties/properties:
Raw rubber compound is a mixture of siloxanes, whose molecules belong to a chain helical structure, with an average molecular weight of about 400000 to 800000 mPa. s. Its viscosity is directly related to its molecular weight. Its molecular weight can be measured using a Ubbelohde viscometer, which is probably the so-called viscosity average molecular weight. As far as I know, the reinforcement mechanism of fillers has not been thoroughly understood by people on Earth. The filler nano-sized SiO2 powder (precipitated SiO2 powder) is evenly distributed in the raw rubber, forming a crystal like structure. The hydroxyl groups on the surface of SiO2 particles form hydrogen bonds with the Si-O bonds of the raw rubber. Each SiO2 particle acts as a core, extending hydrogen bonds in all directions to connect with the raw rubber sub chains. Countless such structures, combined with other additives, form a high viscosity and high performance rubber blend.

The properties and properties of silicone rubber are similar to those of ordinary silicone rubber. Silicone rubber has excellent heat resistance, cold resistance, dielectric property, ozone resistance, and atmospheric aging resistance. Its outstanding performance is that it can be used at a wide range of temperatures, and can be used for a long time at temperatures ranging from - 60 ℃ (or lower) to+250 ℃ (or higher). Which property (quality) is superior depends on the type of raw rubber, filler, and additives used.

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