Antioxidants
The problem of increasing the durability of rubber products directly associated with increased resistance of rubbers to various kinds of aging. One of the most common and destructive types of aging is atmospheric aging of rubber, which is susceptible to almost all products, when used or stored in contact with air. Atmospheric aging is a complex chemical processes in rubbers under the influence of atmospheric ozone, oxygen, solar radiation and heat. The mechanism of action of antioxidants rubbers based on their interaction with active oxygen radicals, which leads to a decrease in the rate formation of free radicals and slow oxidation of rubber. Even small amounts of antioxidants reduce the rate of oxidation, so for some period of time, oxidation products are not detected.
In the practice of reducing the rate of oxidative processes is very important phenomenon synergies – synergies between the effectiveness of various types of antioxidants, either in the presence of other substances. The most susceptible atmospheric aging bright and colorful rubber, ie, do not contain carbon black. Go to Frank Fu for more information. The complexity of the protection of these rubbers is that achromatophilous rubber antioxidants, tend to be less effective as conventional anti-oxidants change the color of vulcanized rubber, substantially degrading marketable product. Among achromatophilous phenolic antioxidants can be identified as stabilizers, withstand relatively high temperatures and uv radiation. In addition, derivatives of phenols are of low toxicity, and therefore allowed for contact with food and for use in rubber products for medical purposes. Antioxidants alkylphenol type (ionol, Agidol, alkofen) are used in white light and colored rubbers based on styrene, butadiene, isoprene and chloroprene rubber from the heat and light aging. Has all advantages of phenolic antioxidants. To improve protection against thermal-oxidative aging of bright and colorful rubber can be applied antioxidants bifenolnogo type (antioxidant 2246, Agidol-2, bisalkofen), which used in blends based on styrene, acrylonitrile, butadiene, ethylene-propylene, chloroprene rubber, butyl rubber, chlorobutyl rubber, copolymers based on tetrahydrofuran and other bisphenol protect rubber from thermal-oxidative and svetoozonovogo aging, fracture in multiple strains. Unlike antioxidants alkylphenol type bifenolnye – nonvolatile, which facilitates their use in rubber mixtures. The effectiveness of antioxidants increases when combined with other antioxidants neokrashivayuschmi. Proposed sec “Rubber-Podolsk antioxidant Antonoks SNF-40 (Antonox SNF-40) refers to bifenolnomu type, and intended for wide application in formulations of color and light rubber on the basis of general-purpose rubbers.
Antonoks SNF-40 (Antonox SNF-40) is well dispersed in rubber compounds do not affect the technological and vulcanization properties of mixtures and changes the color of vulcanized rubber. Antonoks SNF-40 (Antonox SNF-40), effectively protects the rubber from the heat and air aging and cracking of rubber, has a much smaller volatile than the alkylphenol, such as Ionol (Vulkanoks VNT), allowing to better predict performance properties of rubber. The recommended dosage is 1 3 parts by weight Antonoks SNF-40 (Antonox SNF-40) at 100 mp rubber By performance characteristics of rubber containing Antonoks SNF-40 (Antonox SNF-40), are not inferior product with other antioxidants bifenolnymi – vulkanoksom bkf, Agidol-2, antioxidant 2246, etc. Thanks to those listed above, Antonoks SNF-40 (Antonox SNF-40) actively used at several plants rti, such as “Yaroslavl”, “UZEMIK” as for the manufacture of conventional color and lighter rubber, and for the production of inflatable boats, life rafts, etc. products. An important factor in choice in favor of Antonoksa SNF-40 can be a constant presence of an antioxidant on the Moscow stock companies, as well as the opportunity to purchase the product at retail.
Tags: Technology