| 摘要 |
Olefin polymers are stabilized against deterioration caused by exposure to ultraviolet light or heat by means of a minor proportion of 3,9-bis(2,2,6,6- tetramethyl-4-piperidinyloxy)-2,4,8,1 0,3,9-tetraoxadiphospha(5,5)spiro- undecane having the formula <IMAGE> or a salt thereof. The compound of the above formula can be prepared by reacting a compound of formula I with a compound of formula II or the corresponding P,P'-dimethoxy or P,P'-dichloro derivative <IMAGE> |
