Gabriel Ríos Valer; Gisela Díaz; Juan M Giussi; Marcelo Ceolín
Abstract
The molecular architecture of polymers is a crucial feature in the moment of think the relationship between properties and applications. The same polymer can present important differences according to its architecture and leads to different possible applications. In this paper, we describe the well preparation ...
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The molecular architecture of polymers is a crucial feature in the moment of think the relationship between properties and applications. The same polymer can present important differences according to its architecture and leads to different possible applications. In this paper, we describe the well preparation of hyperbranched copolymers based on bis (Hydroxyl-Methyl) propionic acid polyester (MPA). The co-monomers introduced via atom transfer radical polymerization were methyl methacrylate (MMA) and styrene (St). In order to study the effect of confinement, linear PMMA and PSt have been prepared, and moreover different levels of branching of each polymer were prepared. The synthesised star PMPA-PMMA and PMPA-PSt copolymers have been characterized and identified by infrared spectroscopy and nuclear magnetic resonance spectroscopy. Thermal transitions in solid state were studied using differential scanning calorimetry, and the thermal stability was evaluated by thermogravimetric analysis. Finally, solution properties have been evaluated thought Dynamic Light Scattering. Our results, obtained by a meticulous and systematic comparative study, showed a clear tendency between architectural level and thermal properties. Moreover, properties in solution revealed interesting response due to the modification of solvent nature.Copyright © VBRI Press.
I. Katime; A. Alvarez-Bautista; E. Mendizabal; L.G. Guerrero-Ramirez; J.R. Ochoa-Gomez
Abstract
A series of star–shaped poly(acrylamide–co–[2–(acryloyloxy)ethyl] trimethyl ammonium chloride) were prepared by inverse microemulsion polymerization. The growth of side chains in the arms of the precursor has been carried out using different compositions of the comonomers acrylamide ...
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A series of star–shaped poly(acrylamide–co–[2–(acryloyloxy)ethyl] trimethyl ammonium chloride) were prepared by inverse microemulsion polymerization. The growth of side chains in the arms of the precursor has been carried out using different compositions of the comonomers acrylamide and [2–(acryloyloxy)ethyl] trimethyl ammonium chloride) (Q9). The characterization and star structure were determined by nuclear magnetic resonance, FTIR, MALDI–TOF and DSC. The dimensions of the particles were determined by quasielastic light scattering and transmission electron microscopy. Quasi–spherical particles of star polymers in the nanozise range were obtained which might be useful for the controlled transport and release of several biologically active drugs.
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