Revonox® 608 is the best material in terms of its hydrolytic and thermal stabilities among spiro phosphite antioxidants. At ambient temperature, Revonox® 608 maintains its free-flowing properties even after being exposed to a highly-humid environment (> 80%) for more than 30 days. This is superior performance than the general spiro antioxidant Deox 604 (CAS no. 26741-53-7), which deliquesced only three days under the same conditions. Due to its large molecular weight, the 10% weight loss temperature of Revonox® 608 exceeds 340 °C as measured by TGA, which is 100 °C higher than the commodity phosphite antioxidant, Deox 68 (CAS no. 31570-04-4).
Unlike other phosphite antioxidants, Revonox® 608 will not discolor when molten. Therefore, Revonox® 608 is highly recommended for use with engineering plastics such as PC, PET, PBT, and PEEK which are generally processed at elevated temperatures. In the PET multi-extrusion test conducted at 280 °C, when used in combination with the hindered phenolic antioxidant, Deox 10, Revonox® 608 demonstrates a high antioxidation efficiency with an improved color protection compared with Deox 68. Revonox® 608 has a sister version available called Revonox® 608T which has a 1% maximum loading of amines as hydrolysis stabilizers and is recommended for use with PA, PP, PE, and PVC.