Technology term explanation: liquid, quasi-liquid or quasi-solid material to resist the flow of the volume characteristics, that is, by external force flow, the molecules presented by the internal friction or flow resistance. Usually the viscosity and hardness are proportional.
The ability of the material to resist the hardening of the hard objects onto its surface is called hardness. Silicone rubber has a Shore hardness range of 10 to 80, which gives the designer the freedom to choose the desired hardness with the utmost freedom to best achieve the specific function. The mixing of the polymer substrates, fillers and additives in different proportions can achieve various intermediate hardness values. Likewise, the time and temperature of the heating cure can also change the hardness without destroying other physical characteristics.
Third, the tensile strength.
Tensile strength refers to the force required to create a rubber material sample tear in each range unit. Hot tensile sulfur solid silicone rubber tensile strength range between 4.0-12.5MPa. Fluorosilicone rubber tensile strength range between 8.7-12.1MPa. Liquid silicone rubber tensile strength range between 3.6-11.0MPa.
Four, tear strength.
The resistance to incision or scoring is increased when a force is applied to a cut specimen. Even after the cut placed in a very high torsional stress, hot and sulfur solid silicone rubber can not be torn. Hot-sulfur solid-state silicone rubber tear strength range between 9-55 kN / m. Fluorosilicone rubber tear strength range between 17.5-46.4 kN / m between. Liquid silicone rubber tear strength range between 11.5-52 kN / m between.
Usually refers to the "limit rupture elongation" or when the sample is broken relative to the original length of the increase in the percentage. Hot-sulfur solid-state silicone rubber generally has an elongation in the range of 90 to 1120%. Fluorosilicone rubber generally has an elongation of between 159 and 699%. Liquid silicone rubber in general elongation between 220 to 900%. Different processing methods and the choice of hardening agent can greatly change its elongation. Silicone rubber elongation and temperature have a great relationship.
Six, operating time.
The operating time is calculated from the moment the colloid is added to the vulcanizing agent. This time of operation and the subsequent vulcanization time is not completely limited, the colloid from the moment to join the curing agent has been carried out vulcanization reaction, the operation time is that the product 30 minutes of vulcanization reaction can not affect the quality of the finished product. So the more the product operation process saves time on the finished product more favorable.
Seven, curing time.
Some places will say that curing time. That is, after such a long time the vulcanization of silica gel is basically over. This is basically the end of the product is already available, but in fact there is a small part of the curing reaction is not over. So the use of silicone rubber products, such as silicone molds usually put a period of time and then put into use.