Sharif Digital Repository

In this study, a semi-conductive nanocomposite for electrically controlled drug delivery is introduced. Hydrolyzed collagen known as a naturally abundant polypeptide was modified with polycaprolactone. This modification changed the mechanical properties of the hydrolyzed-collagen. A hydrogel compound was synthesized through radical co-polymerization of acrylic acid on the backbone of this biocompatible polymer in the presence of a crosslinker. The reaction parameters affecting the water absorbency of the hydrogel were optimized using Taguchi method. In situ polymerization of aniline, incorporated conductive nanofiber pathways throughout the hydrogel matrix. 1H NMR, TGA, AFM, SEM, FTIR,... 

In this study, we attempt to synthesize novel acrylated agarose (ACAG)-based hydrogels with three different crosslinking densities. Acrylate groups were inserted onto agarose (AG) backbone through homogeneous reaction of acrylic monomers with AG backbone. Hydrogels were synthesized through radical copolymerization of a mixture of acrylic acid and 2-hydroxyethyl acrylate with ACAG in aqueous solution using ammonium persulfate as an initiator. Infrared spectroscopy (FTIR) was carried out to confirm the chemical structure of the hydrogel. Moreover, morphology of the samples was assessed by scanning electron microscopy. The equilibrium swelling capacities of synthesized hydrogels were evaluated... 

In the present work, synthesis and swellability of acrylatedstarch-based hydrogels was investigated. Acrylic groups were introduced onto starch backbone by a homogeneous synthesis to produce starch monomers with three different degree of substitution (DS). The radical copolymerization of acrylatedstarch (AST) with acrylic acid (AA) and acrylamide (AAm) was carried out in aqueous solution using ammonium persulfate (APS) as an initiator. Infrared spectroscopy (FT-IR) and TGA thermal analysis were carried out to confirm the chemical structure of the hydrogel. Moreover, morphology of the samples was examined by scanning electron microscopy (SEM). Their equilibrium swelling degree was evaluated... 

Polycarboxylate superplasticizers based on acrylic acid (AA) and maleic anhydride (MAn) were synthesized via free-radical copolymerization with an ethylene glycol monomer and characterized. The copolymerization temperature (ranging from 50 to 90 °C) appeared to be the key operating factor governing the chemical structure of the superplasticizers. The chemical structures of the products were analyzed by gel permeation chromatography, whereas an optimized sample was further analyzed by Fourier transform infrared spectroscopy and 1H-NMR. Superplasticizers of the AA and MAn classes were then incorporated into concrete, and their performances were measured by slump and slump loss tests, where a... 

A superhydrophobic nanocomposite coating was fabricated using a simple procedure. The nanocomposite is composed of an acrylic copolymer and modified silica nanoparticles. The acrylic copolymer was prepared by free radical copolymerization of methyl methacrylate and dodeycl methacrylate monomers. Silica nanoparticles were synthesized and modified with an alkyl silane reagent, hexadecyltrimethoxysilane. A mixture of acrylic copolymer and modified silica nanoparticles, dispersed in dichloromethane, was then sprayed on glass and filter paper surface. Chemical composition and structure of the coatings were investigated by FTIR, FESEM, AFM, 1H-NMR and GPC. The wettability of the prepared coating...