When we receive a Technical Data Sheet (TDS) for a liquid silicone rubber (LSR), we typically encounter several key indicators: 

Hardness, Viscosity, Tear Strength, Tensile Strength, Elongation, and for mold-making silicones, Reproduction Count.

Do you understand what these indicators mean? And what kind of silicone is the most suitable raw material for your industrial production?

For liquid silicone rubber, viscosity is the decisive starting point—it directly determines whether the material can be successfully processed and molded. If the viscosity is too high, the material cannot flow effectively under injection pressure, resulting in short shots, incomplete filling, or even making injection molding entirely impossible. In short, viscosity dictates whether a part "can be made at all." Viscosity, in turn, reflects the material's structure and composition—formulations with higher hardness and strength typically require more fillers and exhibit higher viscosity.

However, viscosity is the starting point, not the finish line. In customer-specific material selection, the following indicators carry equal "decisive" weight:

Hardness (Shore A): This determines the tactile feel and functional performance of the final product. A baby pacifier requires softness (10–20A), whereas a sealing ring needs firmness (50–70A). Choosing the wrong hardness means the product won't function as intended.

Tear Strength: This is the lifeline for molds and durable components. For silicone molds subjected to repeated demolding cycles, or flexible parts that bear stress, tear strength directly determines the product's service life.

Therefore, when selecting a liquid silicone rubber, first check whether the viscosity matches your processing method, then, among grades that meet your hardness requirements, prioritize those with higher tear strength.

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