Silicone rubber production and performance!
As far as I know, the compound is solid silicone rubber. Usually a one-component gel, a crosslinking agent, a catalyst, an inhibitor and a compound. Mixing rubber are generally high-temperature vulcanization after extrusion molding, unlike liquid glue is mostly two-component and there is room temperature vulcanization, low temperature vulcanization, high temperature vulcanization three categories. As for the silicone rubber compound in front of the "green" word, I think no need, because the silicone rubber are very environmentally friendly.
First, the production process:
With silicone rubber raw rubber and white carbon black and other fillers in the kneading machine after kneading, in the two roller mixing machine plus cross-linking agent, catalyst, inhibitors, a variety of color materials such as mixing. The resulting rubber is called silicone rubber compound.
Second, the physical properties / performance:
Physical nature / performance I can only provide about:
1, before curing (curing), as "solid", according to the color of the color when mixing, depending on the white, plastic value of 200 ~ 300 or so;
2, after curing, no transparency of the pigment is not good liquid glue, "light transmittance" is not higher than 70%, the same "hardness" of the rubber "rebound value" is generally lower than the liquid glue, but "mechanical properties "Is generally higher than the liquid glue," tensile strength "to 10 ~ 20MPa," tear strength "up to 40 ~ 60KN / m," elongation "generally better than the same hardness liquid glue. The "vulcanization temperature" is generally between 140 and 180 degrees. "Linear shrinkage" I will not say it.
Third, the chemical properties / performance:
Mixing glue is a mixture of siloxanes, its molecules belong to the chain spiral structure, the average molecular weight of about 40 ~ 80 million mPa.s between the viscosity and molecular weight is directly related. Umbrella viscometer can be used to determine the molecular weight, is probably the so-called viscosity average molecular weight bar On the filler of the reinforcement mechanism, as far as I know, so far the earth has not completely understand. Is mainly filled with nano-SiO2 powder (precipitated SiO2 powder) evenly distributed in the raw rubber, the formation of a similar crystal structure, SiO2 particles on the surface of the hydroxyl and raw rubber Si-O bond to form hydrogen bonds, each SiO2 particles as A core, extending in all directions hydrogen bonds and raw rubber molecular chain connection, numerous such a structure, plus some other additives, to form a high viscosity and high performance of the compound.
And the general nature of the silicone rubber (quality) can be almost. As the "silicone rubber" Baidu Encyclopedia said, silicone rubber has excellent heat resistance, cold resistance, dielectric, ozone resistance and resistance to atmospheric aging and other properties, silicone rubber is the use of a wide temperature, (Or lower) to + 250 ° C (or higher) for long periods of time. As for what kind of quality (quality) can be more superior, by the use of raw materials and fillers and additives type of decision.