Liquid Silicone Rubber (LSR) Injection Molding---Process History and Development

Liquid silicone rubber molding is now becoming more and more important in medical components and other silicone products's industrial, But how it works during these decades and how it develop in recent years ?

During the 1940s,high molecular weight silicone gums were introduced commercially . Pre-existing rubber processing equipment was utilized to mill, and mold the materials. The 1950s saw the introduction of Room Temperature Vulcanizing (RTV) rubbers which came in the form of two
component liquids or pastes. When mixed, RTVs vulcanize at room temperature over extended periods of time. LSRs are the result of these early RTV silicones. Formulations which could be cured more rapidly under higher temperature were developed during the late 1970s. As was
previously done with rubber processing equipment, plastics processing equipment was soon co-opted for manufacturing LSR products. Injection molding machine barrels were water cooled, rather than heated, and shutoff nozzles were added to prevent material backflow during curing. This is the basic production setup for LSRs used today. Great advancements in pumping LSRs have been made in the past two decades.

Early pumping equipment relied solely on direct pneumatic driving to transfer material, and off ratio mixes were common. More recent developments use closed-loop controls to ensure proper the proper ratio of the two components. Material transfer rates are measured directly by flow metering devices and fed back to the control unit to either increase or decrease pumping speeds.

Liquid silicone rubber injection molding is still changing these days, more and more new features and solving ways are bringing out by some outstanding engineers , it will getting more and more perfect in the coming days . For more further information, visit www.tymsilicone.com .