Liquid Silicone Rubber MoldingMolding

Use our Liquid Silicone Rubber Molding guidelines to understand what’s achievable in your project.

Liquid Silicone Rubber Molding

Liquid silicone rubber (LSR) injection molding is a thermoset process that mixes two components with a platinum catalyst in a static mixer before being vulcanized in a mold to produce the part with almost no wasted material.

How Does Liquid Silicone Rubber Molding Work ?

Liquid Silicone Rubber, as the name suggests, is liquid enough to be mixed in a static chamber: Inside two compounds are mixed together in equal parts with a third platinum catalyst and any desired color pigment. The final mixed liquid rubber compound is then pumped through tubes into a mold where the low viscosity of the liquid silicone rubber delivers a perfect seal, thereby creating a final part without any burrs. Once in the mold, the liquid silicone rubber is heated and hardened in a process known as vulcanization.

Like any standard injection molding tool, a liquid silicone rubber mold is made via CNC machining a heat resistant, durable, metal (steel or aluminum) to create a mold able to consistently withstand the molding process. Once cut: form, fit and function are signed off, before the tool is polished as per customer surface finish specifications. There are a wide range of surface finishes available at HCBluestone. When it comes to manufactured parts or products: if it’s possible, it’s possible in the Pearl River Delta (PRD).

Liquid Silicone Rubber is a thermosetting polymer and as such the final part remains in its final molded state. It can’t be melted again and remolded, like a thermoplastic material. Parts are checked and batched as they come off the injection molding machine. From there, according to the project requirements, they’re moved on either to product assembly, or straight to the packaging department for quality control, before shipping.

Is Liquid Silicone Rubber Molding best for your project ?

Liquid silicone rubber is often used in the mass production of high quality parts needed to withstand extreme temperatures. Here are some of LSR’s key characteristics :
Can meet FDA requirements and many other approval classes
High tear, tensile and elongation strength
Hardness range of 5 to 80 Shore A
Excellent flexibility
Can withstand extremely high and low temperatures – can be close to hot moving parts without losing stability
Fire retardant / Will not melt
Will not corrode or stain other materials.
Resistant to bacteria growth
Has no discernible taste or odor.
Can be formulated a variety of ways
Resistant to oxidation and some chemical solutions
Excellent insulating properties
Is naturally transparent and can become most colors

Advantages of Liquid Silicone Rubber Molding

Batch stability
Consistent ready to use material
Easily repeatable consisent process
Almost Zero Waste
Short Cycle Time
Shorter lead times in mass production
‘Flashless’ Technology
No burrs
Automated Process