RING-OPENING POLYMERIZATION OF 2-PHENYL-1,3,2-DIOXAPHOSPHORINANE INITIATED WITH NEW CATALYST SYSTEM USING A HALOBENZENE AND NICKEL(II) BROMIDE

Ring-opening polymerization of 2-phenyl-1,3,2-dioxaphosphorinane (a six-membered cyclic phosphonite, 4) has been initiated with a new catalyst system of a halobenzene and NiBr2. The polymerization proceeded in a living nature to produce poly(phosphinate) consisting exclusively of a ''normal'' unit. The kinetic analysis of the polymerization of 4 initiated with the catalyst system was successfully carried out. The rate constant of propagation (k(p)) was much lower than that initiated with Mel. Linear and star-shaped telechelic polymers were synthesized using di-, tri-, tetra-, and hexa- halobenzenes as a catalyst component.