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Micrometer sized copolymeric particles of glycidyl methacrylate and octadecyl methacrylate (poly(GMA-co-OMA) were prepared by reversible addition fragmentation chain transfer (RAFT) mediated dispersion copolymerization technique using polyvinyl pyrrolidone (PVP) as steric stabilizer and 2-cyano-2-propyl benzodithioate (CPB) as RAFT agent in ethanol. Different reaction parameters on the characteristics of poly(GMA-co-OMA) particles and their effects were investigated thoroughly in the presence of RAFT agent. Formation of poly(GMA-co-OMA) particle sizes, its stability and morphology depends on the concentration of RAFT agent, stabilizer as well as the monomer ratio. Spherical poly(GMA-co-OMA) particles of size ranges1-13 μm were obtained after optimization of the ratio between GMA and OMA. In the presence of RAFT, with the increased amount of hydrophobic monomer OMA, instabilities of the particles are observed while particle sizes found to be decreased with the increased amount of GMA in the reaction mixture. Prepared poly(GMA-co-OMA) particles were characterized by different analytical techniques such as NMR, IR, GPC, TGA etc. while Field Emission Scanning Electron Microscope (FE-SEM) was applied to study the poly(GMA-co-OMA) particle sizes and its morphology. [ABSTRACT FROM AUTHOR]

Synthesis of uniform poly(glycidyl methacrylate-co-octadecyl methacrylate) (poly(GMA-co-OMA)) particles with smooth surfaces were carried out by dispersion copolymerization. Copolymeric particles with stable and smooth surfaces in the size range of 1.0–15 µm were obtained without any sign of coagulation. The effects of different reaction parameters in the preparation of uniform poly(GMA-co-OMA) particles were investigated. The reaction temperature as well as molar ratio of GMA to OMA has effect significantly on the formation of stable and uniform poly(GMA-co-OMA) particles. The final copolymeric particle sizes and stability increases from 2.4 µm to 10 µm with the increased temperature from 50 to 70 °C. For the formation of ideal spherical shape of poly(GMA-co-OMA) particles, ratio between GMA and OMA were optimized. Particle instabilities observed with the increase of hydrophobic OMA while particle sizes were found to be decreased with the increase of GMA content. This result suggests that the introduction of OMA in the dispersion copolymerization of GMA plays an important role for the synthesizing of uniform poly(GMA-co-OMA) microparticles with colloidal stability. [ABSTRACT FROM AUTHOR]

Abstract: Because of their numerous biological as well as industrial importance, the study of Schiff bases is an emerging field for the researchers, in recent time. In this study, we have designed some Schiff bases derived from biologically important precursors. The antioxidant activities of the designed compounds are thoroughly studied theoretically using density functional theory taking various parameters like bond dissociation enthalpy, ionization enthalpy, proton dissociation enthalpy, and electron transfer enthalpy followed by the study of effects of solvent, spin density, and molecular orbital on antioxidant activity of the compounds. The comparison of antioxidant activity of the compounds with that of phenol and their parent aldehydes reveals the superior antioxidant activity of the designed compounds. This study contributes towards the information of an important bridge between bioorganic and computational chemistry. [ABSTRACT FROM AUTHOR]