Sulfur dioxide, terpolymerization

Spontaneous copolymerization of cyclopentene (CPT) with sulfur dioxide (SOt) suggests the participation of a charge transfer complex in the initiation and propagation step of the copolymerization. The ESR spectrum together with chain transfer and kinetic studies showed the presence of long lived SOg radical. Terpolymerization with acrylonitrile (AN) was analyzed as a binary copolymerization between CPT-SOt complex and free AN, and the dilution effect proved this mechanism. Moderately high polymers showed enhanced thermal stability, corresponding to the increase of AN content in the terpolymer. 

As a development of our studies on charge transfer complexes and polymerization, we reported on the spontaneous copolymerization of cyclopentene and sulfur dioxide (11), and kinetic evidence for the participation of the charge transfer complex in the copolymerization was presented. This paper discusses the terpolymerization of cyclopentene, sulfur dioxide, and acrylonitrile to give further evidence for the charge transfer... 

Iwatsuki and Yamashita (46, 48, 50, 52) have provided evidence for the participation of a charge transfer complex in the formation of alternating copolymers from the free radical copolymerization of p-dioxene or vinyl ethers with maleic anhydride. Terpolymerization of the monomer pairs which form alternating copolymers with a third monomer which had little interaction with either monomer of the pair, indicated that the polymerization was actually a copolymerization of the third monomer with the complex (45, 47, 51, 52). Similarly, copolymerization kinetics have been found to be applicable to the free radical polymerization of ternary mixtures of sulfur dioxide, an electron donor monomer, and an electron acceptor monomer (25, 44, 61, 88), as well as sulfur dioxide and two electron donor monomers (42, 80). 

The diradical nature of the intermediate in the copolymerization of monomers through a charge transfer intermediate has been suggested by Zutty et al. (88) as a result of studies on the copolymerization and terpolymerization of monomer systems containing bicycloheptene and sulfur dioxide. The third monomer apparently enters the copolymer chain as a block segment, while the donor-acceptor monomer pair enter the chain in a 1 1 molar ratio, irrespective of the ratio present in the monomer mixture. 

Terpolymerization of Butadiene, trans-Pipery-lene with Sulfur Dioxide [53]... 

Terpolymerization of Allyl Alcohol, Acrylic Acid, and Sulfur Dioxide [64]... 

Here, a third monomer can be included to interpolymerize with the complex that acts as a unit. The product is a terpolymer. A diradical intermediate was also postulated in sulfur dioxide copolymerizations and terpolymerizations with bicycloheptene and other third monomers. These third monomers enter the copolymer chain as block segments, while the donor-acceptor pairs enter the chains in a one-to-one molar ratio. This one-to-one molar ratio of the pairs is maintained, regardless of the overall nature of the monomer mixtures. 

Radical Co- and Terpolymerization of Norbornenes with SO2. A typical polymerization procedure is described below. The fluoroalcohol monomer la (2.74 g, 0.01 mol) was placed in 25 mL of liquid sulfur dioxide at -60 to which were added... 

Radical copolymerizadon of substituted norbomenes mth sulfur dioxide produced alternating copolymers in excellent yields in a few hours. The copolymers had an OD of 0.25-0.33/pm at 193 nm. The acidic di(trifluoromethyl)carbinol structure incorporated into the poly(norbomene sulfone) provided an extremely fast dissolution rate in aqueous base. Terpolymerization with carbo-/>butoxynorbomene resulted in an exponential decay of the ssolution rate. In contrast to poly(styrene sulfones), however, poly(norbomene sulfones) exhibited unacceptably fast etching in... 

Styrene terpolymerization, with sulfur dioxide and methyl methacrylate, 418 Styromal resins, SMA copolymers, 426, 445 2-Styryl-2-methyl-1,3-dioxane, MA copolymerization, 331... 

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