Stereospecific Polymerization of Butadiene by Coordinated Cationic Mechanism

Trans-stereospecific polymerization of butadiene and random copolymerization with styrene using borohydrido neodymium/magnesium dialkyl catalysts

The combination of a neodymium borohydride, Nd(BH4)3(THF)3 (1) or Cp*Nd(BH4)2(THF)x (2), with MgBuEt (BEM), affords an efficient and highly selective (up to 96.7% 1,4-trans) catalyst for butadiene polymerization. In the presence of excesses of Mg co-catalyst, polymer chain transfer takes place between neodymium and magnesium, and significant amounts of 1,2-units are observed. When considered fo...

Regio- and stereospecific living polymerization and copolymerization of (E)-1,3-pentadiene with 1,3-butadiene by half-sandwich scandium catalysts.

The living isospecific-cis-1,4-polymerization and block-copolymerization of (E)-1,3-pentadiene with 1,3-butadiene have been achieved for the first time by using cationic half-sandwich scandium catalysts.

Catalytic Polymerization of Butadiene in Aqueous Systems with Cationic Nickel(II) Complexes

The cationic nickel(II) complexes [(η-C3H5)Ni(SbPh3)2][B(3,5-(CF3)2C6H3)4] (2) and [(η3C3H5)Ni(SbPh3)2][Al(OC(CF3)3)4] (3) were prepared and their polymerization activities in aqueous systems were compared with [(η-C3H5)Ni(η-BHT)][B(3,5-(CF3)2C6H3)4] (1) (BHT ) 3,5-di-tert-butyl-4-hydroxytoluene). Cispolybutadiene is formed in nonaqueous solution polymerization. The presence of water decreases ...

Highly trans-stereospecific Isoprene Polymerization by Neodymium Borohydrido Catalysts

Preparation of cationic polyacrylamide by aqueous two-phase polymerization

Cationic polyacrylamide (CPAM) was synthesized by aqueous two-phase polymerization technique using acrylamide (AM) and dimethylaminoethyl methacrylate methyl chloride (DMC) as raw materials, aqueous polyethylene glycol 20000 (PEG 20000) solution as dispersant, 2,2′-azobis(2-amidinopropane) dihydrochloride (V-50) as initiator and poly(dimethylaminoethyl methacrylate methyl chloride) (PDMC) as st...