Oil-bleeding

Kohara S et al. (1999) Thermoplastic olefin elastomer compositions with low compression set, no oil bleeding, and good weather resistance. JP Patent 11181172... 

The market for silicone elastomer products of this decade has expanded dramatically with increase of business machines and home electronics such as personal computers, copy machines, printers, TV sets, video cameras and so on. Various silicone products are used for electrical and electronic fields Based on the electrical conductivity, there are three grades of silicone rubbers. Insulating stocks are used for anode caps used for the cathode ray tube of TV sets, or plug boots and oil bleed connectors for automobiles, for instance. Electrically conductive silicones are used in products like rubber contact switches for TV remote controllers, handy phones, zebra connectors, EMI (electron magnetic interference) shield gasket and so on. And semiconductive silicone elastomers used for semiconductive rollers for plain paper copy machines and page printers, and antistatic materials. These relatively new materials have the volume resistivity of 10 -10 ohm-cm, and may be used in many other industrial fields. 

Oil-Bleeding Properties of Self-Lubricating Liquid Silicone Rubbers... 

Keywords silicone rubber (MVQ), liquid silicone rubber (LR), liquid injection molding (LIM), oil-bleeding, diffusion, methylphenyl silicone fluid... 

Where finished articles are not stored under controlled conditions, seasonal temperature fluctuations can influence oil-bleeding to the extent that a silicone rubber article which exudes hardly any silicone fluid in winter could be well wetted in sununer. 

In cases where single wire seals or cable bushing mats are fabricated in automated processes, such fluctuations in oil-bleeding can cause considerable difficulties. Since not only temperature and pressure but also storage duration will influence the amount of silicone fluid on the surface of the article, it is essential to optimize storage conditions. 

Fig. 9. Oil-bleeding properties of Elastosil LR 3088/50 (manufacturer Wacker-Chemie GmbH, Munich) at different temperatures (shown as weight loss over time) [12],...

Silicone elastomers are heat, aging, and chemical resistant. They are characterized by having unmodified mechanical properties over a wide temperature range from -70 to 200 ""C. Standard types are available in a hardness of 20 to 90 Shore A. Electrically conductive types, fluorosilicone types, oil-bleeding, fast cross-linking, and hard modified types are offered. 

Features Best suited where higher durometer and tens. str. are required compared to Akrofax A Soft further reduces possibility of oil bleeding to surif. 

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