Methacrylate-based polymer blends containing oligomeric 1,2-polybutadienes

Abstract

Partly miscible polymer blends with semi-IPNs structure built from polydimethacrylate networks and hydroxyl-terminated liquid polybutadienes with predominant 1,2-structure (LBH) were prepared by photopolymerization method. Photopolymerization kinetics of dimethacrylate-LBH mixtures were monitored by DSC technique under isothermal conditions. Kinetic curves and related parameters, like polymerization rate and degree of double bond conversion were determined as functions of dimethacrylate structure, LBH molecular mass, and its content in the mixture as well as polymerization temperature. The photopolymerization kinetics and activation energy for the polymerization rate were discussed taking into account the phase separation occurring during the curing reaction. The extent of phase separation (based on T g 's measurements) depended on LBH content and dimethacrylate chemical structure. The effect of LBH content on hardness of polymer blends was also examined.

Hybrid Free-Radical/Cationic Phase-Separated UV-Curable System: Impact of Photoinitiator Content and Monomer Fraction on Surface Morphologies and Gloss Appearance

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“…7 Polymerization induced phase separation can also be realized for systems monomer/dissolved polymer. 8,9 In this way photopolymerization kinetics may provide a convenient approach to control heterogeneity. The polymerization of such systems shows a multistage kinetics, which results from the appearance of two compositionally different phases, polymerizing more or less independently.…”