Polymer-Bound Antioxidants

Abstract

Abstract The service demands placed on finished rubber products continue to increase year after year. Tires, hose, automotive belts, and components are expected to perform without failure for periods which are now two to three times those expected just ten years ago. Many of these increased demands are the result of radical and innovative changes in the design and construction of rubber products. One obvious change has been the change from bias ply to radial passenger tire construction. This has increased the expected service mileage from approximately 20 000 miles (32 Mm) to over 40 000 miles (64 Mm). Other changes have resulted in response to environmental legislation. The switch to nonleaded gasoline has increased the aromatic content of our fuel. It has also resulted in the use of additional and different fuel additives such as methanol, ethanol, and t-butylmethyl ether. These aggressive solvent changes obviously affect the extractability of stabilizers from hose products. Additional legislation has changed mileage and pollution requirements for engines. This has, in general, increased the operating temperature under the hood, resulting in more severe aging conditions for belts, cables, and hoses. At the same time, it has increased the demands placed on seals and gaskets which are in contact with hot lubricating oils. Similar situations also apply in areas outside the automotive area. Rubber products used in the garment and carpet industries are also exposed to extraction conditions during detergent washing and dry cleaning processes.