LIM™ 6000 General Purpose Liquid Silicone Rubbers

Momentive LIM™ 6000 series is a family of fast-curing and injection-moldable liquid silicone rubbers (LSR) supplied in the form of ready-to-use components (part A and part B). Momentive performance materials offer formulations of a wide range of elastomeric solutions including automotive, healthcare, and consumer goods. Momentive LSR products exhibit exceptional mechanical properties, stability, pigment integration, and high tear strength. 

Momentive performance materials and elastomers provide high tensile strength and outstanding thermal range for high-speed injection molding processes and applications. The LIM™ 6000 series consists of two-component formulations with relatively low viscosity and fast cure rates and are excellent materials for injection-molded silicone applications. In comparison to organic elastomers, the LIM™ 6000 silicone materials allow for easy processing and more than often do not require secondary post-cure operations. Momentive LIM™ 6000 series features low durometer and non-tackiness when end products require sensory characteristics like soft to the touch. 

• High tear resistance and tensile strength
• LSR is clear but easily pigmentable
• Improved adhesion to a wide variety of substrates, including engineered thermoplastics and metals
• Short cycle time, flash less, and trim-free manufacturing lead to rapid cure speeds and higher productivity
• Outstanding thermal stability across a wide range of temperatures
• Available in hardnesses of 10, 30, 40, 50 and 60 Shore A
• Excellent release from metal molds
• Repeat sterilizability for use in health care and medical devices
• Biocompatibility (USP Class VI, ISO10993)
• FDA Indirect Food Contact compliance
• BFR compliance

LIM liquid silicone rubbers are supplied in the form of ready-to-use components (part A and part B). 
 

Dosing:
A mixture of (1:1) ratio of the two components is transferred from the original containers to a static mixer or the mixing chamber by hydraulic piston pumps that can be connected by an interlocking system that ensures a 1:1 feed ratio. Color pastes can be fed to the system, then the mixture is injected into the heated mold. 
 

Injection pressure:
An injection pressure of 50 to 150 bars is ordinarily sufficient for LSR that is typically dependent on the cross-section of the feed channel.
 

Processing and curing: 
The mixture vulcanizes at temperatures of 140-230°C to form a cured silicone rubber within a few seconds depending on the grade. To prevent premature vulcanization in the nozzles and cylinders, cool down the parts with water to a temperature of about 20°C.
 

​Post curing:
During postcuring, it is primarily siloxanecycles that evaporates, leading to a slight loss of weight. It is recommended to maintain a supply of fresh air into the post-curing oven to prevent the formation of flammable air/siloxane mixtures.