Technology terminology: The volumetric characteristic of liquid, pseudo-liquid or pseudo-solid material that resists flow, that is, the internal friction or internal flow resistance between molecules when it flows under the action of an external force. Under normal circumstances, viscosity is directly proportional to hardness.
The ability of a material to locally resist hard objects pressed into its surface is called hardness. Silicone rubber has a Shore hardness range of 10 to 80, which gives designers full freedom to choose the required hardness to best achieve specific functions. Various intermediate hardness values can be achieved by mixing polymer substrates, fillers and additives in different proportions. Similarly, the time and temperature of heating and curing can also change the hardness without destroying other physical characteristics.
Tensile strength refers to the force required for each range unit to tear a piece of rubber material sample. The tensile strength of thermally vulcanized solid silicone rubber is between 4.0-12.5MPa. The tensile strength of fluorosilicone rubber is between 8.7-12.1MPa. The tensile strength of liquid silicone rubber is in the range of 3.6-11.0MPa.
The resistance to impede the expansion of the cut or notch when force is applied to the cut sample. Even if it is placed under extremely high torsional stress after cutting, the thermally vulcanized solid silicone rubber can not be torn. The tear strength range of hot-vulcanized solid silicone rubber is between 9-55 kN/m. The tear strength range of fluorosilicone rubber is between 17.5-46.4 kN/m. The tear strength of liquid silicone rubber ranges from 11.5-52 kN/m.
"" usually refers to the "Ultimate Break Elongation" or the percentage increase relative to the original length when the sample breaks. Thermally vulcanized solid silicone rubber generally has an elongation in the range of 90 to 1120%. The general elongation of fluorosilicone rubber is between 159 and 699%. The general elongation of liquid silicone rubber is between 220 and 900%. Different processing methods and choice of hardener can greatly change its elongation. The elongation of silicone rubber has a lot to do with temperature.
The operating time is calculated from the moment when the colloid is added to the vulcanizing agent. There is actually no complete limit between this operation time and the subsequent vulcanization time. The colloid has undergone vulcanization from the moment the vulcanizing agent is added. This operation time means that the 30-minute vulcanization reaction of the product does not affect the quality of the finished product. Therefore, the more time saved in the product operation process, the more beneficial it is to the finished product.
Some places will say it is curing time. In other words, the vulcanization reaction of silica gel is basically over after such a long time. This basically ends, which means that the product is already available, but in fact there is still a small part of the curing reaction that has not yet ended. Therefore, products made of silicone rubber, such as silicone molds, usually take a period of time before being put into use.