4. Injection point
A cold runner system is used when molding LSR. The advantages of this type of rubber can be maximized and productivity can be increased to the maximum. By processing products in such a way, it is not necessary to remove the injection channel, thus avoiding the need to increase the labor intensity of the operation, and in some cases, avoiding a large amount of material waste. In many instances, the molding channel-less structure also reduces operating time.
For products injected with conventional sprue (such as submerged sprue and conical sprue), it is appropriate to use a small-diameter injection port to add material (the diameter of the injection port is usually 0.2mm-0.5mm) to pour. Low-viscosity LSR compounds, like thermoplastic compounds, it is important to balance the runner system so that all cavities are evenly filled with the compound. Simulation software for designing runner systems can greatly simplify the mold development process and prove its effectiveness through mold filling tests.
5. Demolding
Through the vulcanization of the liquid silicone rubber is easy to adhere to the surface of the metal, the flexibility of the product will make it difficult to release the mold. However, LSR has high-temperature tear strength that enables it to be demolded under normal conditions, and even larger products will not be damaged. The most common release techniques include stencil release, pin release and pneumatic release. Other common techniques are roller scraping, export plate stripping, and automatic royal molding.
When using a mold release system, it is important to keep it within a high degree of accuracy. If the gap between the push pin and the guide sleeve is too large, or if the gap becomes large due to wear of the parts over time, glue overflow may occur. An inverted cone or mushroom shaped push pin works well because it allows for greater contact pressure and facilitates improved sealing.
6. Mold materials
Mold pallets commonly used non-alloy tool steel (no.1.1730, DIN code C45W) made of dry need to withstand high temperatures of 170 ° C - 210 ° C mold pallets, taking into account the impact resistance, should be used to pre-tempered steel (no.1.2312, DIN code 40 CrMn-M oS 8 6) manufacturing. For mold pallets with set cavities, they should be manufactured from nitrided or tempered heat-treated acetal steel to ensure high temperature resistance.
For highly filled LSR, e.g. oil-resistant grade LSR, it is recommended that the molds be made of harder materials, e.g. bright chromium-plated steels or powdered metals specially developed for this purpose (no. 1.2379, DIN code X 155 CrVMo121). When designing molds for highly abrasive materials, those parts subjected to high friction should be designed as replaceable formations so that the entire mold does not have to be replaced. The internal surfaces of the mold cavity have a significant effect on the finish of the product. Most obviously, the molded part will match the surface of the cavity exactly. Molds for transparent products should be made of polished steel. Surface-treated Chin/Nickel steel is extremely abrasion-resistant, while polytetrafluoroethylene (PTFE)/Nickel makes mold release easier.
7. Temperature Control
Generally speaking, it is preferable to use electric heating for LSR molding, usually by band heaters, cartridge heaters or heating plates. The key is to make the temperature field uniformly distributed throughout the mold to promote uniform curing of LSR. On large molds, is a cost-effective heating method when pushing the oil temperature control heating.
Wrapping the mold with an adiabatic plate is good for reducing heat loss. Unsuitability of any part of the hot mold may subject it to large temperature fluctuations between operating processes or cause runout. If the surface temperature drops too low, the adhesive curing rate will be slowed down, which often prevents the product from being released from the mold and causes quality problems. A certain distance should be maintained between the heater and the parting line to prevent the template from bending and distorting, forming overflow glue burrs on the finished product.
Proper design and conception can ensure LSR injection molding, where the mold is very important. The above mold design principles aim to make the rubber fill the mold cavity, shorten the curing time, the finished product is of high quality and high yield, so that the silicone rubber processor can get good economic benefits.

Room termperature curing polysilazane, pls check IOTA 9150, IOTA 9150A. 
High termperature curing polysilazane, pls check IOTA 9108, IOTA 9118.