Vìsnik Odesʹkogo Nacìonalʹnogo Unìversitetu: Hìmìâ (Nov 2020)
STUDY OF THE KINETIC OF COPOLYMERIZATION OF MODIFIED POLYGLYCOLMALEINATPHTHALATES IN THE PRESENCE OF COBALT DIACETYLACETONATE
Abstract
Investigated as activators of radical-chain copolymerization of unsaturated polyester resins with methyl methacrylate acetylacetonates: cobalt (II) dihydrate, ferum (III), copper (II), chromium (III), nickel (II) dihydrate, zirconium (IV). Unsaturated polyester resins were obtained by polycondensation of maleic and phthalic anhydrides with ethylene glycol at 180 °C. Benzoyl peroxide was used as an initiator. Copolymerization was studied at temperatures from 30 to 60 °C by dilatometry using special collapsible dilatometers. The ratio of the unsaturated oligomer in the initial mixture to the monomer methylmethacrylate was 1:1. Determined the initial rate and temperature coefficient of the copolymerization reaction. A method for pretreatment of an activator solution in a monomer is proposed, which increases its efficiency in the process of redox radical copolymerization. After treatment, the content of Co2+ ions in the solution increases from 0.02 mol/l to 0.33 mol/l. The effect of both the nature of the activator and the modifier of polyester resins on the effective initial rate and temperature coefficient of the copolymerization reaction is shown. The following were used as modifiers of unsaturated oligoesters: 1,10-phenanthroline, diphenylamine, 1,2,3-benzotriazole. For comparison, methyl methacrylate was copolymerized with oligodiacrylates: triethyleneglycoldimethacrylate and bis-di- (triethyleneglycoldimethacrylate)phthalate. The following physical and mechanical characteristics of the obtained copolymers were determined: hardness, density, glass transition temperature. Initiating systems have been proposed for practical use in the copolymerization of unsaturated polyesters with vinyl monomers in a non-isothermal mode with the lowest risk of overheating. Mathematical calculations by the finite element method have been carried out and it has been shown that the use of the proposed methods makes it possible to increase the volume of the reaction mixture by several times in comparison with traditional systems.
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