Graft Polymerization Of Methyl Acrylate Research Articles

Hydrazinolyzed cellulose-g-polymethyl acrylate as adsorbent for efficient removal of Cd(II) and Pb(II) ions from aqueous solution.

Hydrazinolyzed cellulose-graft-polymethyl acrylate (Cell-g-PMA-HZ), an efficient adsorbent for removal of Cd(II) and Pb(II) from aqueous solution, has been prepared by ceric salt-initiated graft polymerization of methyl acrylate from microcrystalline cellulose surface and subsequent hydrazinolysis. The influences of initial pH, contact time, and temperature on adsorption capacity of Cell-g-PMA-HZ as well as adsorption equilibrium, kinetic and thermodynamic properties were examined in detail. As for Cd(II) adsorption, kinetic adsorption can be explained by pseudo-second-order, while adsorption isotherm fits well with Langmuir isotherm model, from which maximum equilibrium adsorption capacity can be derived as 235.85 mg g-1 at 28 °C. Further thermodynamic investigation indicated that adsorption of Cd(II) by adsorbent Cell-g-PMA-HZ is endothermic and spontaneous under studied conditions. On the other hand, isotherm of Pb(II) adsorption fits well with Freundlich isotherm model and is more likely to be a physical-adsorption-dominated process. Consecutive adsorption-desorption experiments showed that Cell-g-PMA-HZ is reusable with satisfactory adsorption capacity.

Hydrazinolyzed cellulose-g-polymethyl acrylate as adsorbent for efficient removal of Cu(II) and Ni(II) ions from aqueous solution

BACKGROUND Although methyl acrylate has been graft polymerized from cellulose and functionalized with hydrazine and hydroxylamine for removal of copper and nickel ions, the adsorption capacity was less than 80 mg g−1. The present work reported hydrazinolysis of cellulose-graft-polymethyl acrylate and remarkably improved adsorption capacity for Cu(II) and Ni(II) in aqueous solution. RESULTS Hydrazinolyzed cellulose-graft-polymethyl acrylate (Cell-g-PMA-HZ) has been prepared by ceric salt-initiated graft polymerization of methyl acrylate from microcrystalline cellulose surface and subsequent hydrazinolysis with hydrazine hydrate. The successful synthesis was confirmed by Fourier-transform infrared spectroscopy, 13C-NMR, elemental analysis, scanning electron microscopy and thermogravimetric analysis. Adsorption behavior of Cell-g-PMA-HZ for Cu(II) and Ni(II) were studied through batch static adsorption processes and column chromatography methods. The influences of graft yield, initial pH, contact time and temperature on adsorption capacity of Cell-g-PMA-HZ as well as adsorption equilibrium, kinetic and thermodynamic properties were studied in detail. Kinetic adsorption can be explained by pseudo-second-order and adsorption isotherms fitted with Langmuir isotherm model, from which maximum equilibrium adsorption capacity can be derived as 229.36 mg g−1 for Cu(II) and 173.91mg g−1 for Ni(II) at 28°C. Further thermodynamic investigation indicated that adsorption of Cu(II) and Ni(II) by adsorbent Cell-g-PMA-HZ was exothermic and spontaneous under the studied conditions. CONCLUSIONS Hydrazinolysis of cellulose-graft-polymethyl acrylate has been accomplished. As an adsorbent, the prepared Cell-g-PMA-HZ was reusable and fairly efficient for removal of Cu(II) and Ni(II) from aqueous solution. © 2015 Society of Chemical Industry

Radiation synthesis of polypropylene-acrylate grafted fiber and its remediation in the spillage of water-insoluble organic chemicals

A new kind of functionalized polypropylene(PP)-acrylate grafted fiber were prepared by radiation-induced graft polymerization of methyl acrylate (MA), ethyl acrylate(EA) and butyl acrylate (BA) monomer onto the PP fiber matrix, as a recovery adsorbent for insoluble organic chemicals. The grafting conditions of monomer concentration and irradiation time on the grafting degree were optimized. The obtained grafted fiber sample was identified by Fourier transform infrared (FT-IR) spectrometer and scanning electron microscopy (SEM) to characterize the chemical and morphological changes of the polypropylene fiber surface. The adsorption results indicated that the grafted fiber could be used to remove organic chemicals from water surface. The adsorption capacity of grafted fiber with different acrylate monomer was obviously different for the same chemicals, therefore, investigations with respect to organic removal, dynamic oil retention, and reusability, the effect of monomer polarity on the adsorption capacity of grafted fiber was especially highlighted in this study.

A Strategy for Synthesis of Magnetic Nanoparticles with "Well-Defined" Polymers via Reversible Addition Fragmentation Chain Transfer Polymerization Under Ultrasonic Irradiation

The controlled graft modification of Fe3O4 magnetic nanoparticles has been achieved by reversible addition fragmentation chain transfer (RAFT) polymerization under ultrasonic irradiation. The nanoparticles of Fe3O4 were first prepared by a chemical co-precipitation method, and reacted with 3-aminopropyltriethoxylsilane (KH550), and subsequently with S-1-dodecyl-S'-(alpha,alpha'-dimethyl-alpha'-acetic acid) trithiocarbonate (DDACT) to serve as RAFT agent. The graft polymerization of methyl acrylate was carried out under ultrasonic irradiation (28 KHz, 60 W). The first-order kinetics and the polymers with narrow molecular weight distributions suggested the polymerization proceeded via RAFT process. The resultant products were characterized by Fourier transform infrared spectrometer (FT-IR), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), high performance particle sizer (HPPS) and Gouy magnetic balance. The resultant products with good paramagnetism could be well modified with the "well-defined" polymers via RAFT polymerization under ultrasonic irradiation, thereby providing a new method to well modify magnetic nanoparticles.

Controlled grafting modification of silica gel via RAFT polymerization under ultrasonic irradiation

The controlled graft modification of silica gel has been achieved by RAFT polymerization under ultrasonic irradiation. Silica gel was first dispersed in dry toluene under ultrasonic irradiation, and then reacted with 3-aminopropyldimethylethoxylsilane (KH550), and subsequently with S-1-dodecyl-S′-(α,α′-dimethyl-α″-acetic acid)trithiocarbonate (DDACT) to serve as RAFT agent. The graft polymerization of methyl acrylate was carried out under ultrasonic irradiation (59 kHz, 90 W). The poly(methyl acrylate) (PMA) grafted silica gel was characterized by Fourier transform infrared spectrometry (FT-IR), field-emitting scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The results show that the graft polymerization was well controlled by the RAFT process, and the PMA modified silica gel particles were synthesized successfully. The graft content could reach 32% within 6 h though there was an inhibition of about 50 min in the graft polymerization. Each silica gel particle was coated with an outer layer of PMA chains, and no aggregation was detected in the SiO 2- g-PMA dispersion. This work indicated that ultrasonic initiated RAFT polymerization can be a method to modify silica gel with “well-defined” graft polymers.

Preparation of polymer electrolyte membranes consisting of alkyl sulfonic acid for a fuel cell using radiation grafting and subsequent substitution/elimination reactions

Polymer electrolyte membranes (PEMs) consisting of alkylsulfonic acid were successfully synthesized by radiation-induced graft polymerization of methyl acrylate (MA) into a poly(ethylene- co-tetrafluoroethylene) (ETFE) film, followed by sulfonation at an α-carbonyl carbon of the MA units in the grafting chain using an equimolar complex of chlorosulfonic acid and dioxane (ClSO 3H-complex). Sulfonation reaction with ClSO 3H-complex in the grafted chains of acrylic acid derivatives (acrylic acid and N, N-dimethylacrylamide) other than MA in the film could not be performed. The ion-exchange capacity (IEC) and ion conductivity of the MA-grafted PEM were controlled in the respective ranges of 0.54–1.47 mmol/g and 0.014–0.14 S/cm by changing the grafting degree. It has been confirmed by titrimetric and gravimetric analyses of sulfonic and carboxylic acids in the film that the sulfonation reaction is accompanied with decarboxylation of the MA units equimolar to the substituted sulfonic acids (substitution of carboxylic acid with sulfonic acid), and that the sulfonation degree was ca. 30%.

Grafting of Poly(alkyl (meth)acrylates) from Swellable Poly(DVB80-co-HEMA) Microspheres by Atom Transfer Radical Polymerization

We report the graft polymerization of methyl acrylate (MA), methyl methacrylate (MMA), hydroxyethyl methacrylate (HEMA), and 2-(dimethylamino)ethyl methacrylate (DMAEMA) by atom transfer radical polymerization (ATRP) from lightly cross-linked poly(DVB80-co-HEMA) microspheres. These poly(DVB80-co-HEMA) microspheres were prepared by precipitation copolymerization and subsequently modified by reaction with 2-bromopropionyl bromide to serve as ATRP macroinitiators. MMA, MA, and HEMA were then grafted from these initiator microspheres at room temperature using CuBr/Me4cyclam as catalyst. The graft sites, and hence the grafted polymers, are distributed throughout the initiator microspheres. Addition of a second monomer formed grafted block copolymers, indicating that a significant portion of the first grafts could be reactivated. The final particles represent novel, high-capacity polymer supports comprised of swellable core particles carrying 5.09 and 5.18 mmol/g of grafted poly(DMAEMA) and poly(MMA-b-DMAEMA), respectively. The grafted particles were characterized using ESEM, FTIR, Coulter particle sizing, and potentiometric titration.

Effects of preparation condition of photoinduced graft filling-polymerized membranes on pervaporation performance

Modification of poly(acrylonitrile) membrane was carried out by heterogeneous photoinduced graft polymerization of methyl acrylate from the vapor phase. The technique of transmembrane monomer flow has proved to be effective for filling pores. The effect of preparation conditions like initiator concentration, reaction time and monomer concentration on the membrane separation was investigated. These graft modified membranes showed benzene permselectivity for benzene/cyclohexane mixture (50/50, v/v) on pervaporation.

Emulsion graft polymerization: mechanism of formation of dispersions

Three stages of the kinetics of graft polymerization of methyl acrylate onto water soluble polymers have been investigated. Polymer particles of graft copolymers contained polyacrylic chains, monomer and water during the whole process. Graft copolymer, formed on the first stage of the polymerization, is a stabilizer of polymer particles in water dispersion. The distribution of monomer between water phase and polymer particles showed that the polymerization proceeds generally in the particles. Nephelometric investigations and adsorption titration of dispersions showed that the adsorption saturation of dispersion particles can change during the process and its final value is high for graft copolymers of water soluble cellulose derivatives and nitrolignin.

Kinetics of Particle Formation at the Graft Polymerization of Methylacrylate onto Hydroxyethyl Cellulose

The kinetics of polymer particle formation and distribution of monomers between a solution and a dispersed phase at the graft polymerization of methylacrylate onto hydroxyethyl cellulose has been studied. The particle number increases at the first stage of polymerization, then it is constant. The concentration of adsorbed monomer decreases during the polymerization process. The monomer concentration in the dispersed phase is greater than in the solution. A mathematical model of particle formation and monomer adsorption in the polymerization process has been suggested. Some values of rate constant ratios have been calculated.

Graft polymerization of methyl acrylate onto granular starch: Comparison of the Fe+2/H2O2 and ceric initiating systems

Graft polymerizations of methyl acrylate (MA) onto granular cornstarch were carried out in water with both ferrous ammonium sulfate/hydrogen peroxide (FAS/H 2 O 2 ) and ceric ammonium nitrate (CAN) initiation. Starch concentrations were 10, 20, and 30% in water, and the amount of MA used was either 0.5, 1, or 2 mol per AGU of starch. Two concentrations of FAS/H 2 O 2 were used : 1 mol each of FAS and H 2 O 2 per 100 AGU of starch, and 1 mol per 1000 AGU. Significant amounts of acetone-extractable PMA homopolymer were produced, and homopolymer formation was especially high at the 1 : 100 ratio. Sharp exotherms were observed, and reaction mixtures reached maximum temperature within 2 min or less. Total conversions of MA to PMA were higher at the 1 : 100 ratio, and conversions in some polymerizations were nearly quantitative. CAN-initiated polymerizations were run under the same conditions used for FAS/H 2 O 2 ; however, the amount of CAN used was limited to 1 mol per 100 AGU because of low conversions at the 1 : 1000 ratio. Compared with FAS/H 2 O 2 , CAN gave more moderate exotherms ; and longer time periods were required for reaction mixtures to reach maximum temperature. CAN gave quantitative conversions of MA to PMA, but only low percentages of PMA homopolymer were observed. Differences between FAS/H 2 O 2 and CAN initiation are consistent with differences in the two initiation mechanisms. High levels of homopolymer produced on starch granule surfaces with FAS/H 2 O 2 could be seen in scanning electron micrographs and were also apparent in infrared spectra obtained with an attenuated total reflectance (ATR) cell. ATR spectra of acetone-extracted products indicated that the amount of PMA actually grafted to starch granule surfaces was similar with both initiating systems. Tensile properties of extruded ribbons prepared from these polymers did not vary greatly with the initiator used.

Graft polymerization of methyl acrylate onto granular starch: Comparison of the Fe2/H2O2 and ceric initiating systems

Graft polymerizations of methyl acrylate (MA) onto granular cornstarch were carried out in water with both ferrous ammonium sulfate/hydrogen peroxide (FAS/H2O2) and ceric ammonium nitrate (CAN) initiation. Starch concentrations were 10, 20, and 30% in water, and the amount of MA used was either 0.5, 1, or 2 mol per AGU of starch. Two concentrations of FAS/H2O2 were used: 1 mol each of FAS and H2O2 per 100 AGU of starch, and 1 mol per 1000 AGU. Significant amounts of acetone-extractable PMA homopolymer were produced, and homopolymer formation was especially high at the 1:100 ratio. Sharp exotherms were observed, and reaction mixtures reached maximum temperature within 2 min or less. Total conversions of MA to PMA were higher at the 1:100 ratio, and conversions in some polymerizations were nearly quantitative. CAN-initiated polymerizations were run under the same conditions used for FAS/H2O2; however, the amount of CAN used was limited to 1 mol per 100 AGU because of low conversions at the 1:1000 ratio. Compared with FAS/H2O2, CAN gave more moderate exotherms; and longer time periods were required for reaction mixtures to reach maximum temperature. CAN gave quantitative conversions of MA to PMA, but only low percentages of PMA homopolymer were observed. Differences between FAS/H2O2 and CAN initiation are consistent with differences in the two initiation mechanisms. High levels of homopolymer produced on starch granule surface with FAS/H2O2 could be seen in scanning electron micrographs and were also apparent in infrared spectra obtained with an attenuated total reflectance (ATR) cell. ATR spectra of acetone-extracted products indicated that the amount of PMA actually grafted to starch granule surfaces was similar with both initiating systems. Tensile properties of extruded ribbons prepared from these polymers did not vary greatly with the initiator used. © 1996 John Wiley & Sons, Inc.1 This article is a U.S. Government work and, as such, is in the public domain in the United States of America.

Graft polymerization of methyl acrylate–vinyl acetate mixtures onto starch

Starch-g-poly(methyl acrylate-co-vinyl acetate) copolymers having a range of poly(vinyl acetate) contents, were prepared by a ceric-initiated grafting procedure identical to that used to prepare starch-poly(methyl acrylate). A rapid analytical method using FTIR spectroscopy has been developed to determine the poly(vinal acetate) content of polymer grafts as well as ungrafted homopolymer. Selected polymers have been extrusion-processed to yield continuous plastic ribbons and their tensile properties have been measured

Synthesis of graft copolymers of acrylic monomers onto amylose. II. Study of the ceric ion behavior

AbstractA study of the ceric ion consumption during graft polymerization of methyl acrylate (MA), ethyl acrylate (EA), ethyl methacrylate (EMA), and butyl methacrylate (BMA) with amylose was carried out. Grafted acrylic polymers were isolated by the acid hydrolysis method. Weight‐average and number‐average molecular weights were determined by gel permeation chromatography (GPC). The number of grafted chains (mmol) ranged from 8.70 × 10−3 to 12.35 × 10−3 for acrylates and from 3.20 × 10−3 to 6.80 × 10−3 for methacrylates. These results were related to others obtained from the ceric ion consumption studies.

Kinetics of graft polymerization of methyl acrylate to water soluble polysaccharides

In the absence of an emulsifier the graft polymerization of methyl acrylate to water soluble polysaccharides obeys the main regularities of emulsion polymerization processes. The polymerization rate in the second stage of the process studied (up to a 40–50% degree of conversion) remains constant on account of the gel effect. The kinetic parameters of the reaction were found to be in keeping with the proposed kinetic scheme.

Study of the grafting of methyl acrylate to (ethylene oxy) cellulose

The authors have studied the influence of the conditions of graft polymerization of methyl acrylate to (ethylene oxy) cellulose (EOC) on the physicochemical indicators of grafted copolymers. The formation of grafted copolymers is confirmed by IR spectroscopy. From the dependence of the efficacy of grafting on the concentration of (ethylene oxy) and monomer and also the kinetics of degradation of persulphate in presence of EOC, the nitroxide radical and the monomer it is concluded that reactions involving an initiator and its radicals play a role in the process of graft polymerization.

Anionic graft polymerization of methyl acrylate to protein functional groups.

AbstractGraft polymerization of methyl acrylate to functional groups in proteins was studied with model compounds and with whole gluten proteins. Polymerization was carried out in the presence of sodium hydride or sodium in dimethyl sulfoxide. Initiation proceeds by an anionic mechanism, and the rate‐determining step is the production of the initially formed carbanion. The rate of disappearance of methyl acrylate was followed via gas chromatography. Amino acid analyses indicated that the functional groups of the amino acids, as well as the peptide bonds, were acting as the initiation sites in proteins. Reaction rates of the functional groups were determined on model compounds in the presence of sodium and sodium hydride. With both the model compounds and the proteins, polymerization was initially rapid and then leveled off, although rates depended on the concentration of activator and acrylate. Methoxyl group analyses of modified model compounds and proteins indicated that from 5 to 10 methyl acrylate residues were introduced per reactive site.

THE CHANGES IN FINE STRUCTURE OF THE RAYON BY GRAFT POLYMERIZATION OF METHYL ACRYLATE

Previous works in this series3), 4) have shown the lowering in the order of cellulose by graft polymerization of methyl acrylate (MA) onto rayon filament. The present investigation was undertaken to clarify whether the orientation of cellulose is changed by graft polymerization of MA onto rayon filament.Samples used in this work were prepared by the same method as that presented in the previous papers3), 4). Samples grafted under swollen state are designated A-sample and those under unswollen state as B-sample respectively. Results obtained are as followings:(1) It is expected that the area of the cross section of grafted filament increase linearly with the amount of polymer grafted, but the observed area is larger than the expected in the region of high content of grafted polymer. Those results suggest the disorientation of the cellulose chains by grafting.(2) X-ray counter curve along the diffraction ring is flattend by grafting.(3) The dichroic ratio of the filament decreases by grafting. The difference between A and B samples in dichroism is not recognized. Then the decrease in the modulus by grafting is attributed not only to the disordering of structure, but also to the disorientation. The difference between modulus of A and B-samples previously reported4) arise from the difference in the order of cellulose, because the degree of disorientation by grafting indicates no difference between A and B-samples.