Synthesis and characterization of a terpolymer derived from styrene, methyl styrene, and polyaniline and its organoclay nanocomposite

Chitosan-grafted-poly(methacrylic acid)/graphene oxide nanocomposite as a pH-responsive de novo cancer chemotherapy nanosystem

The aim of this study was the design and development of a novel de novo drug delivery system for cancer chemotherapy. For this purpose, chitosan (CS) functionalized using phthalic anhydride followed by 4-cyano, 4-[(phenylcarbothioyl) sulfanyl] pentanoic acid as a chain transfer agent (CTA) to afford CS-CTA macroinitiator. The synthesized CS-CTA macroinitiator was then copolymerized with methacrylic acid (MAA) monomer using reversible addition-fragmentation chain transfer (RAFT) polymerization technique to produce chitosan-graft-poly(methacrylic acid) (CS-g-PMAA) graft copolymer. Afterward, graphene oxide (GO) nanosheets were incorporated into the synthesized copolymer through the physical interactions. The CS-g-PMAA/GO nanocomposite was loaded with doxorubicin hydrochloride (DOX) as a universal anticancer drug. The biocompatibility, DOX-loading capacity, and pH dependent drug release behavior of the developed nanocomposite were also investigated. As the experimental results, as well as superior biological and physicochemical features of CS and GO, we envision that the developed CS-g-PMAA/GO nanocomposite may be applied as de novo drug delivery nanosystem for cancer chemotherapy.

Grafting of poly[(methyl methacrylate)-block-styrene] onto cellulose via nitroxide-mediated polymerization, and its polymer/clay nanocomposite

For the first time, nitroxide-mediated polymerization (NMP) was used for synthesis of graft and block copolymers using cellulose (Cell) as a backbone, and polystyrene (PSt) and poly(methyl metacrylate) (PMMA) as the branches. For this purpose, Cell was acetylated by 2-bromoisobutyryl bromide (BrBiB), and then the bromine group was converted to 4-oxy-2,2,6,6-tetramethylpiperidin-1-oxyl group by a substitution nucleophilic reaction to afford a macroinitiator (Cell-TEMPOL). The macroinitiator obtained was subsequently used in controlled graft and block copolymerizations of St and MMA monomers to yield Cell-g-PSt and Cell-g-(PMMA-b-PSt). The chemical structures of all samples as representatives were characterized by FTIR and (1)H NMR spectroscopies. In addition, Cell-g-(PMMA-b-PSt)/organophilic montmorillonite nanocomposite was prepared through a solution intercalation method. TEM was used to evaluate the morphological behavior of the polymer-clay system. It was demonstrated that the addition of small percent of organophilic montmorillonite (O-MMT; 3wt.%) was enough to improve the thermal stability of the nanocomposite.

Novel nanostructured star-shaped polyaniline derivatives and their electrospun nanofibers with gelatin

The aim of this study is the synthesis, characterization and investigation of some physicochemical properties of the star-shaped polyaniline derivatives. The nanofibers of the synthesized star-shaped polymers with gelatin were also prepared.

Synthesis of conductive polyaniline-modified polymers via a combination of nitroxide-mediated polymerization and “click chemistry”

A new strategy for graft copolymerization of aniline onto polystyrene by a multi step process is suggested.

Recent progress in the chemical modification of syndiotactic polystyrene

This review provides a snapshot of recent progress in the chemical modification of syndiotactic polystyrene.

Conductive polymers/zeolite (nano-)composites: under-exploited materials

This review provides a snapshot of recent progress in the synthesis, materials properties, and applications of conductive polymers/zeolite (nano-)composites reported until March 2014.