Dhruba J. Haloi

Atom Transfer Radical Polymerization of Glycidyl Methacrylate (GMA) in Emulsion

This investigation reports atom transfer radical polymerization (ATRP) of glycidyl methacrylate (GMA) and its copolymerization with butyl methacrylate (BMA) in emulsion. Poly(glycidyl methacrylate) (PGMA) was prepared in emulsion using copper bromide (CuBr) as catalyst in combination with 2,2′-bypyridine (bpy) as ligand and methyl 2-bromopropionate (MBrP) as initiator. Different surfactants of Triton series (such as Triton X-100, Triton X-405) were used as emulsifier in these cases. The copolymerization of GMA with BMA was also performed successfully in emulsion via ATRP using the same reaction conditions used for the preparation of PGMA. The stability of the latexes prepared via emulsion ATRP was examined. TEM analysis was carried out to examine the particles sizes of polymer in the latex. Molecular weights and molecular weight distributions of the polymers were determined by GPC analysis. The FT-IR and 1H-NMR analyses indicated that the pendant glycidyl group of PGMA was unaffected during emulsion ATRP. Thermal stability of the polymer was evaluated by thermogravimetric analysis (TGA). Copolymer composition in the copolymer was calculated from the 1H-NMR analysis.

Synthesis and characterization of poly(2-ethylhexyl acrylate) prepared via atom transfer radical polymerization, reverse atom transfer radical polymerization and radical polymerization

AbstractThis investigation reports a comparative study of poly(2-ethylhexyl acrylate) (PEHA) prepared via atom transfer radical polymerization (ATRP), reverse atom transfer radical polymerization (RATRP) and conventional free radical polymerization (FRP). The molecular weights and the molecular weight distributions of the polymers were measured by gel permeation chromatography (GPC) analysis. Structural characterization of the polymers was carried out by 1H NMR and MALDI-TOF-MS analyses. Thermal properties of the polymers were evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The polymerization results and the thermal properties of PEHAs prepared via ATRP, RATRP and FRP were compared. Graphical AbstractA comparative study of poly(2-ethylhexyl acrylate) (PEHA) prepared via atom transfer radical polymerization (ATRP), reverse atom transfer radical polymerization (RATRP) and conventional free radical polymerization (FRP) is reported.

Synthesis of Poly(2-ethylhexyl acrylate)/Clay Nanocomposite via In Situ and Surface Initiated-Atom Transfer Radical Polymerization

This investigation reports a comparative study of the preparation and properties of tailor-made poly(2-ethylhexyl acrylate) (PEHA)/clay nanocomposite prepared via in situ atom transfer radical polymerization and surface initiated atom transfer radical polymerization (SI-ATRP). Being a low Tg (−65 C) material, PEHA has very good film formation property for which it is used in paints, adhesives and coating applications. In situ PEHA/clay nanocomposite was prepared by polymerizing EHA in presence of nanoclay and acetone as additive at 90 C using methyl 2-bromopropionate (MBrP) as initiator, CuBr as catalyst in combination with N,N,N′,N′′,N′′-pentamethyl diethylenetriamine (PMDETA) as ligand. The functionalized nanoclay was used to prepare PEHA/clay nanocomposite in presence of acetone as additive at 90 C using CuBr as catalyst in combination with N,N,N′,N′′,N′′pentamethyl diethylenetriamine (PMDETA) as ligand. Kinetic plots were prepared for in situ ATRP as well as SI-ATRP. The prepared nanocomposites were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and wide-angle X-ray diffraction (WAXD) analyses. Distribution of nanoclay in the polymer matrix was studied by the transmission electron microscopy (TEM).