Sulfonated polymer/silica hybrid nanoparticles were prepared by free radical POLYMERIZATION of 2-acrylamido-2-methyl-1-propane sulfonic acid (PAMPS-g-SN) and styrene sulfonic acid sodium salt (PSSA-g-SN), INITIATED on the SURFACEs of amino propyl-functionalized silica nanoparticles (ASN). Ce (IV) ammonium nitrate/nitric acid and sodium dodecyl sulfate were used as redox initiator and stabilizer, respectively. ASN Nanoparticles were synthesized by a covalently attached 3-aminopropyltriethoxysilane onto the SURFACE of silica nanoparticles. Sulfonated monomers (AMPS or SSA) were then grafted onto the ASN nanoparticles, ultrasonically dispersed in water, using redox initiator system at 40°C. ASN, PAMPS-g-SN and PSSA-g-SN nanoparticles were characterized by Fourier transform infrared (FTIR), thermogravimetry, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses. FTIR and TGA results indicated that both AMPS and SSA monomers were successfully grafted onto the silica nanoparticles. The grafted amounts of sulfonated polymers onto the silica nanoparticles were estimated from TGA thermo grams to be 46 and 22 % for PAMPS and PSSA, respectively. From SEM and TEM micrographs, the average-diameters of the polymer-grafted silica nanoparticles were measured to be < 50 nm with a (semi) spherical morphology, in which several silica nanoparticles were able to form a core with PAMPS or PSSA existing around the silica nanoparticles.

Titanium dioxide (TiO2) nanoparticles, with an average size of about 45 nm, were encapsulated by polystyrene using in situ nitroxide mediated radical POLYMERIZATION in the presence of 3-aminopropyl triethoxy silane as a coupling agent and 2, 2, 6, 6-tetramethylpiperidinyl-1-oxy as a initiator.First, the initiator for nitroxide mediated radical POLYMERIZATION was covalently bonded onto the SURFACE of Titanium dioxide nanoparticles through our novel method. For this purpose, the SURFACE of TiO2 nanoparticle was treated with 3-aminopropyl triethoxy silane, a silane coupling agent, and then these functionalized nanoparticles was reacted with ± -chloro phenyl acetyl chloride.The chlorine groups were converted to nitroxide mediated groups by coupling with 1-hydroxy-2, 2, 6, 6-tetramethyl piperidine. These modified TiO2 nanoparticles were then dispersed in styrene monomers to carry out the in situ free radical POLYMERIZATION.

In the present investigation, silica nanoparticles have been coated with poly (styrene-co-acrylonitrile) (SAN) copolymer brushes synthesized via SURFACE-INITIATED atom transfer radical POLYMERIZATION (ATRP). In the initial step, silica nanoparticles were functionalized with triethoxysilane-based ATR initiator, 6-(2-bromo-2-methyl) propionyloxy hexyl triethoxysilane. Successful formation of the covalent linkages between ATRP initiator and silica nanoparticles is further corroborated using thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The SURFACE INITIATED ATRP of the styrene and the acrylonitrile mediated by a copper complex was carried out using the initiator fixed silica nanoparticles in the presence of a sacrificial (free) initiator. The POLYMERIZATION is preceded in a living manner in all examined cases, producing nanoparticles coated with well-defined poly (styrene-co-acrylonitrile) (SAN) brushes with molecular weight in the range of 12-22 kDa. SAN-grafted silica nanoparticles were characterized using TGA which showed significant weight loss in the temperature range of 340-420oC confirming the formation of the polymer brushes on the SURFACE with graft densities in the range of 0.109-0.190 chains/nm2. Successful formation of the SAN copolymer brushes are further characterized by FTIR and proton nuclear magnetic resonance spectroscopy techniques. Differential scanning calorimetric studies revealed that the SAN copolymer grafted onto silica nanoparticles exhibits higher glass transition temperatures than free SAN copolymers. Transmission electron microscopy and dynamic light scattering studies revealed that the SAN copolymer-grafted silica nanoparticles showed relatively fine dispersion in organic solvents such as tetrahydrofuran, when compared to bare silica nanoparticles.

The SURFACE modification of ground tyre rubber (GTR) containing hydroxyl groups was carried out by atom transfer radical POLYMERIZATION using a two-step reaction procedure. The process consisted of immobilization of an ATRP initiator such as 2-bromoisobutyryl bromide and controllable radical POLYMERIZATION of maleic anhydride (MAH). The resulting GTR-g-MAH was characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The results demonstrated that the graft yield of new polymer could reach 69.4% on GTR SURFACE. Then the grafted GTR was used as an adsorbent for removal of lead ions from aqueous solution. It was observed that factors such as solution pH, contact time, initial lead concentration and graft yield exerted considerable influence on lead adsorption capacity of GTR-g-MAH. The adsorption process indicated that the pseudo-second-order kinetic model fitted the experimental data well, and the equilibrium of adsorption could be described by Freundlich isotherm model. The maximum adsorption capacity of GTR-g-MAH calculated from Langmuir isotherm reached 144 mg.g-1. It was found that the GTR-g-MAH particles had significantly greater adsorption capacity and faster adsorption kinetics for lead adsorption than unmodified GTR particles.

Arobust Monte Carlo simulation as a stochastic random-based method was employed to study the bulk photoPOLYMERIZATION of furfuryl methacrylate (FM) at various temperatures. An appropriate mechanism of POLYMERIZATION considering a vast variety of reactions was selected and therefore, a reliable algorithm was designed. In addition, experimental results were used to evaluate the simulation procedure and algorithm and consequently, confirm the simulation results. The concentration profiles of different species with respect to irradiation time were obtained by this simulation method. In addition, the effect of temperature variation on the concentration of species has been evaluated. At higher temperatures, an increase in the rate of FM consumption was revealed which is because of an increment in the propagation rate constants of acrylic macroradicals. At 40°C of the early stages of the photoPOLYMERIZATION, M1* concentration increases rapidly with respect to irradiation time; this is on account of the superior primary initiation constants compared to other temperatures. However, due to the acrylic macroradicals termination, intermolecular degradative transfer, allylic-acrylic termination and acrylic primary termination, M1* concentration reaches a plateau. Moreover, the highest concentration of M1* was achieved at 0°C. A data analysis based on the least square method was performed to evaluate the FM concentration and consequently, a reliable agreement between the experimental data and the Monte Carlo simulation results were obtained at different temperatures.

In this study, the modeling of POLYMERIZATION of 1, 3-butadiene in the presence of hydrogen peroxide has been reported for the first time. For this purpose, the Method of double moments was applied. The modeling has been performed to investigate the effect of reaction condition on the properties of synthesized Polybutadiene, and the role of kinetic coefficients on the output of model i. e. sensitivity analysis. A comprehensive kinetic model was developed based on previous experimental studies. Then, the moment and population balance of the reactants were obtained. Modeling results were used to study the role of initiator concentration and the type of solvent in POLYMERIZATION kinetics and final polymer properties. In addition, the sensitivity of modeling results in a transfer to the initiator, radical coupling and finally transfer to polymer reactions was investigated. This study opens a way for the engineering of manufacturing the Hydroxyl-Terminated PolyButadiene (HTPB) process to obtain the desired products with optimized reaction conditions. Results show that initiator concentration and type of solvent are important in POLYMERIZATION kinetics and properties of HTPBs. A higher amount of initiator increases radical concentration and consequently rates of bimolecular termination and at the lower level, rate of propagation, and polymer double bonds reactions.

A core-shell structure of fluorine-containing polyacrylate latex was synthesized by UV-INITIATED two-stage microemulsion POLYMERIZATION from styrene (St) and hexafluorobutyl acrylate (HFA) in the presence of Irgacure 2959 as hydrophilic photoinitiator at room temperature. The first POLYMERIZATION stage took 12 min and the second stage took 10 min. The conversions of the first and the second POLYMERIZATION stages were about 60 and 85 %, respectively. Fourier transform infrared (FTIR) spectra, transmission electron microscopy (TEM), dynamic light scattering (DLS), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and contact angle analysis were used to characterize the properties of latexes and their films. The DLS analysis results indicated that the size of the fluorine-containing nanoparticle is about 20 nm. The TEM photos showed that the particles have core-shell structure and some of the cores are located in the center and the others deviate from the center of particles. From the FTIR and XPS results, we can infer that the fluorine monomer could be introduced into the copolymer and the fluorine-containing polyacrylate mainly occupies the shell part. The TGA results indicated that the fluorine-containing polyacrylate copolymers exhibited higher thermal stability than that of the fluorine-free one. The contact angle analysis results showed that fluorine monomers make the film SURFACE more hydrophobic.

A new potassium persulfate redox system has been investigated for the graft POLYMERIZATION of vinyl monomers. In this study potassium persulfate system was used for initiation the POLYMERIZATION. Graft POLYMERIZATION of acrylonitrile (AN) onto starch (Sta) was carried out in aqueous solution using potassium persulfate (I) redox system. It was found that the percentage of grafting and rate of grafting were all dependent to some extent, on the concentration of the I, AN, Sta and Sta/ water as well as reaction time and temperature. The kinetics of the graft POLYMERIZATION of AN onto Sta in aqueous solution was studied by Kjeldahl method (quantity and qualitative determination nitrogen content), and the kinetics of AN homoPOLYMERIZATION in the same system was studied by bromometry titration (residue monomer determination). The following rate expression (rate of graft POLYMERIZATION and rate of homoPOLYMERIZATION) Rg=k·[AN]1.185·[I]0.499·[Sta]0.497 and Rh=k·[AN]1.359·[I]0.436 were obtained and a suitable mechanism was suggested. The graft copolymer was investigated with an infrared spectroscope. The overall activation energy was found to be 56.95 kJ/mol within the temperature range of 40-65°C.