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目前显示的是 七月, 2017的博文

Understanding Liquid Silicone Rubber Molding

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Manufacturers commonly use Liquid Injection Molding (LIM) to form Liquid Silicone Rubber (LSR). Unlike compression molding, the mold is first closed and then the material is introduced into the cavities through a system of sprues, runners, and sub-runners. Once the parts are cured, the mold is opened, parts are removed and the process repeats. Let’s take a look at the step-by-step process. The Liquid Silicone Rubber Process 1. The uncured silicone starts off in two barrels — one marked Compound A and the other Compound B. One barrel contains the cures, while the other holds an accelerant.  These two substances are combined and kneaded by an external mixer in a one-to-one ratio, along with any color that is needed. 2. The injection molding machine is programmed and customized to every job. The injection settings are programmed to the proper shot size. The plates and pistons that line up and close the mold have settings for temperature, pressure and cycle time that is adju

What is Liquid silicone rubber?

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Liquid silicone rubber  is a high purity platinum cured  silicone  with low compression set, great stability and ability to resist extreme temperatures of heat and cold ideally suitable for the production of parts, where high quality is a must. Injection molding of liquid silicone rubber Injection molding of liquid silicone rubber  (LSR) is a process to produce pliable, durable parts in high volume. Liquid silicone rubber is a high purity platinum cured silicone with low compression set, great stability and ability to resist extreme temperatures of heat and cold ideally suitable for the production of parts, where high quality is a must. Due to the thermosetting nature of the material, liquid silicone injection molding requires special treatment, such as intensive distributive mixing, while maintaining the material at a low temperature before it is pushed into the heated cavity and vulcanized. Chemically, silicone rubber is a family of thermoset elastomers that

What is silicone rubber? How to choose?

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  Choose silicone rubber – the material that works for you Silicone rubber is an inorganic synthetic elastomer made from a crosslinked silicon-based polymer reinforced with filler. It offers a unique combination of chemical and mechanical properties organic elastomers cannot match. These properties make silicone rubber the material of choice for applications ranging from bakeware to turbocharger hoses. Silicone rubber - Solid state Liquid silicone rubber Why silicone rubber is the better choice? Longer service life in adverse environments Virtually unaffected by weather -- rain, snow, humidity, ozone, or the sun's damaging ultraviolet (UV) rays -- for many years Organic elastomers may become brittle and crack under prolonged exposure to the environment Wider operating temperature range -- from -100 to 316ºC (-148 to 600ºF) Organic elastomers soften and deform irreversibly at temperatures >100ºC (>212ºF); they become brittle at temperature

Difference between Rubber & Plastic

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Key difference : The main difference between the two materials is based on their nature, structure, and production, wherein the plastic is a man made, artificial or a by-product of oil and rubber is a natural product which is derived from the sap of the rubber trees. Plastic and Rubber, are two revolutionary materials that brought growth in the industries. Both, different in their properties, use, and looks, were widely functional in developing new products. Also, both are quite diverse from each other and it is pretty easy to differentiate between them. Plastics are defined as organic materials which have a polymeric structure and are derived from oil or petroleum. They are synthetic or artificial in nature. Also, they are high in molecular mass, which makes them moldable when soft, and are widely used in the manufacture of many materials such as coatings, artificial fibers, etc. Rubber, on the other hand, is defined as an organic material which is derived from the s

What do you know about Plastics?

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What is Plastic? Plastics are the most versatile materials ever invented. Indeed, the word "plastic," which derives from the Greek word  plastikos , meaning to mold or form, has come to be used as a general description for anything particularly adaptable or flexible. Since the first plastic, celluloid, was developed as a replacement for elephant ivory in the 1860s, many different types of plastics, including  nylon , polyethylene, and  Teflon® have revolutionized the manufacture of commercial goods as diverse as nylon stockings and car-body parts. Although the use of  plastic continues to grow and revolutionary new plastics are constantly being developed, concerns have been raised about the environmental effects of using and disposing of so much plastic material, prompting the invention of  bioplastics . Science Plastics are synthetic chemicals extracted mainly from petroleum and composed of  hydrocarbons  (compounds made from chains of hydrogen and carbon  atoms )

Natural rubber & Synthetic rubbers

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Natural rubber Natural Rubber - Solid state Natural rubber is made from a runny, milky white liquid called  latex  that oozes from certain plants when you cut into them. (Common dandelions, for example, produce latex; if you snap off their stems, you can see the latex dripping out from them. In theory, there's no reason why we couldn't make rubber by growing dandelions, though we'd need an awful lot of them. Although there are something like 200 plants in the world that produce latex, over 99 percent of the world's natural rubber is made from the latex that comes from a tree species called  Hevea brasiliensis , widely known as the rubber tree . This latex is about one third water and one third rubber particles held in a form known as a  colloidal  suspension. Natural rubber is a polymer of isoprene (also known as 2-methylbuta-1,3-diene) with the chemical formula (C 5 H 8 )n. To put it more simply, it's made of many thousands of basic C 5 H 8 units (the mon