SYNTHESIS AND CHARACTERIZATION OF NOVEL ORGANONICKEL-ORGANOSILICON ALTERNATING COPOLYMERS

The synthesis and characterization of five novel organonickel-organosi licon alternating copolymers having the repeating unit - C6F4 - Ni(PBu (3))(2) - C6F4 - SiR(2) - [where SiR(2) = SiMe(2) -, - SiMe (Hex) -, - SiPh(2) -, -- SiMe(2) - O - SiMe(2) -, and - SiMe(2) - (CH2) (6) - Si Me(2)-] are reported. The model compounds Ni(PR(3))(2)(1,4C(6)F(4)SiMe (3))(2) (PR(3) = PMePh(2) or PBu(3)) were prepared via reactions of Ni (PR(3))(2)( 1,4-C6F4Li)(2) with 2 equiv of SiMe(3)Cl, and were charact erized by conventional analytical and spectroscopic measurements. The polymers were prepared from the reactions of Ni(PBu(3))(2)(1,4-C6F4Li) (2) with 1 equivalent of SiMe(2)Cl(2) (polymer 1, M ($) over bar omega = 15,800), SiMe(Hex) Cl-2 (polymer 2, M ($) over bar omega = 7300), S iPh(2)Cl(2) (polymer 3, M ($) over bar omega = 8600), O(SiMe(2)Cl)(2) (polymer 4, M ($) over bar omega = 13,900) and (CH2)(6)(SiMe(2)Cl)(2) (polymer 5, M ($) over bar omega = 19,700). The molecular weights for each polymer were fully determined by both GPC and VPO. The multinucle ar (H-1-, F-19-, and P-31 {H-1})- NMR, FTIR, and UV-Visible spectrosco pic data for each polymer unambiguously establishes its repeating unit structure. The observations indicate that introduction of the silyl o r siloxane units into the organonickel backbones has remarkably decrea sed the chain rigidity of the organonickel-organosilicon polymers comp ared to their rigid rod organonickel analogues(i.e., - [ - C6F4 - Ni(P R(3))(2) -](n) -). (C) 1994 John Wiley and Sons, Inc.