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Before you buy a silicone product, you must know if the quality of the  is acceptable. The easiest way to smell the smell of the product with your nose is to stretch it back and forth several times to see how elastic the product is. In addition, as a professional silicone product manufacturer, here are some criteria for judging the quality of silicone products.

The first is the viscosity of the silicone product.

Silicone Elbow
Silicone Elbow

Technical terminology: The volumetric properties of liquid, quasi-liquid or quasi-solid materials, ie the internal friction or flow resistance of molecules flowing under external forces. Generally, viscosity is proportional to hardness.

Second, the hardness of silicone products.

The ability of a material to resist local compression of a hard object is called hardness. Silicone rubber has a Shore hardness range of 10 to 80, which gives the designer the freedom to choose the hardness required to achieve the desired function. Various intermediate hardness values ​​can be achieved by mixing different proportions of polymer substrate, filler and auxiliaries. Similarly, the time and temperature of heating and curing can also change the hardness without damaging other physical properties.

Third, the tensile strength of silicone products.

Tensile strength is the force required for each unit of the rubber sample to be torn. The heat-vulcanized solid silicone rubber has a tensile strength of between 4.0 and 12.5 MPa. The tensile strength of fluorosilicone rubber is between 8.7 and 12.1 MPa. The tensile strength of liquid silicone rubber ranges from 3.6 to 11.0 MPa.

silicone hose
silicone hose

Fourth, the tear strength of the silicone product.

The resistance to expansion of the slit or scratch when a force is applied to the sample having the slit. The hot vulcanized solid silicone rubber cannot be torn even if the cutting is placed under extremely high torsional stress. The hot vulcanized solid silicone rubber has a tear strength between 9 and 55 kN/m. The fluorosilicone rubber has a tear strength of between 17.5 and 46.4 kN/m. The liquid silicone rubber has a tear strength between 11.5 and 52 kN/m.

Fifth, the elongation rate of silicone products.

Usually refers to the “limit elongation at break” or percentage increase of the sample relative to the original length when the sample is broken. The total elongation of the heat-cured solid silicone rubber is between 90% and 1120%. The total elongation of the fluorosilicone rubber is Between 159% and 699%, the total elongation of liquid silicone rubber is between 220% and 900%. Different processing methods and choice of hardener will greatly change the stretching rate. The elongation and temperature of silicone rubber have Great relationship.

Sixth. The operating time of the silicone product.

The operating time is calculated from the moment the colloid is added to the curing agent. There is no complete limit between this operating time and the post curing time. The colloid is vulcanized from the moment the curing agent is added. This operating time means that the product’s 30-minute vulcanization reaction does not affect the quality of the finished product. Therefore, the more time saved in the production process, the better the finished product. Some places will say that it is a cure time now. That is to say, after such a long time, the vulcanization of the silica gel is basically over. This is basically over, which means that the product is already available, but in fact, a small portion of the curing reaction is not over yet. Therefore, products made of silicone rubber, such as silicone rubber molds, are usually put into use for a while.