Plastic antioxidants has been widely used in plastics. Among these,polyolefin, ABS is used the most, followed by POM, PVC and nylon. When use them, two or more antioxidants should be take into consideration, thus can produce advantages of additive, or synergistic effect, in order to obtain better results. ①Additive effects: when take primary antioxidant and secondary antioxidant into use,they play