Antioxidants.Literature describes how to improve the heat resistance of HNBR HNBR Hydrogenated Acrylonitrile-Butadiene Rubber , ACM (Association for Computing Machinery, New York, www.acm.org) A membership organization founded in 1947 dedicated to advancing the arts and sciences of information processing. In addition to awards and publications, ACM also maintains special interest groups (SIGs) in the computer field. and EAM (1) (Enterprise Asset Management) The management and control of the information technology assets within the enterprise. The asset management repository includes a description of the asset as well as contract information pertaining to its acquisition. by the use of antioxidants. Various antioxidants are evaluated in hydrogenated nitrile-butadiene rubber (HNBR), polyacrylic elastomer (ACM) and ethylene-acrylic elastomer (EAM), polymers frequently used in applications requiring high heat and oil resistance. Compounds are aged up to 21 days at 177[degrees]C in air, optionally first immersed in ASTM ASTM abbr. American Society for Testing and Materials 901 oil to remove any soluble antioxidants that could be extracted in service. Similar agings are performed with samples contained in individual test tubes or cells. Primary or radical trap antioxidants are compared, optionally with a secondary or synergist synergist /syn·er·gist/ (-er-jist) a muscle or agent which acts with another. syn·er·gist n. A synergistic organ, drug, or agent. antioxidant. Under the test conditions examined, antioxidant synergists age no better than a corresponding additional amount of primary antioxidant; in all three polymers, the best predictor of air aging at 177[degrees]C is total antioxidant level. Naugard 445 is found to be the most beneficial antioxidant for high temperature performance. Crompton/Uniroyal Chemical Circle 107 on card |
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