Styrene solvent

Figure 3-19 shows a generalized solution process for polymerization of styrene. Actual processes may have up to five reactors in series processes with only one reactor are sometimes used. Styrene, solvent (usually ethylbenzene in amounts of 2-30%), and occasionally initiator are fed to the first reactor. Solvent is used primarily for viscosity control with the amount determined by the exact configuration of the reactor and the polymer molecular weight desired. A secondary function of solvent is control of molecular weight by chain... 

Use Production of phenol, acetone, and a-methyl-styrene solvent. 

Hazard Toxic by ingestion, inhalation, and skin absorption irritant to skin and eyes. Flammable, dangerous fire risk. TLV 100 ppm STEL 125 ppm. Use Intermediate in production of styrene, solvent. 

Styrene-butadiene-styrene Solvent-based and hot-melt glues... 

Fig. 4. Copolymerization of butadiene and styrene in different solvents at 50°C. Parts of butadiene/styrene/solvent/n-butyllithium = 75/25/1000/0.13 (2.0 mmol). From Ref. 50 reprinted by permission of the Rubber Division of the American Chemical Society.

The experimental techniques used were modifications of those previously described, Styrene (Monsanto Co.), divinylbenzene and trimethylol propane triacrylate (Polysciences Inc.) were freed from inhibitor and residual trace polymer by column chromatography on aluminium oxide. Monomers were used immediately after purification. For the actual grafting runs, low density polyethylene films (thickness, 0.12 mm. Union Carbide) were placed as strips (4 x 2 5 cm) in lightly stoppered pyrex tubes (15 x 2.5 cm) containing styrene/solvent solutions (20 ml) at 20 1°C For irradiation, the tubes were held on a circular rack surrounding a 1200 Ci cobalt-60 source The tubes were positioned such that the surfaces of the film were perpendicular, or near perpendicular, to the plane of the radiation At the completion of the irradiation, the grafted polymer films were removed from the monomer solution and exhaustively extracted in... 

Polyethylene can be crosslinked with peroxides to make it more suitable for coatings for electrical power cables [18]. Peroxides are also used to crosslink (also called cure) thermoset polyesters. Thermoset polyesters have a reactive alkene and are used to make fiberglass compositions such as used for boat hulls. Variations are possible, but commonly they are copolymers of fumaric acid or maleic anhydride with phthalic acid or isophthalic acid and a diol. The oligomer is typically dissolved in styrene. When a peroxide is mixed with the solution, crosslinking occurs and the polyester cures. The styrene solvent takes part in the reaction and the solution hardens. 

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