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The radical homopolymerization of N‐tert‐butyl acrylamide (t‐BuAAm) and its copolymerization with methyl acrylate (MA) is studied in ethanol/water solutions over a range of initial monomer and initiator levels between 50 and 70 °C. While short‐chain branching for poly(t‐BuAAm) samples could not be detected by 13C NMR, the reduced rate of monomer conversion with lowered monomer content indicates the formation of mid‐chain radicals (MCR) by backbiting. Adding water as a cosolvent to ethanol significantly increases reaction rates, in agreement with recent pulsed‐laser studies that quantify the influence of solvent composition on homopropagation kinetics. However, the measured drifts in comonomer composition with conversion are well represented by a single pair of reactivity ratios (rMA = 1.12 ± 0.01, rt‐BuAAm = 0.71 ± 0.01) over the complete range of experimental conditions. A mechanistic model developed to describe t‐BuAAm homopolymerization is extended to capture the impact of reaction operating conditions (monomer content and composition, solvent composition, initiator content, and temperature) on the features of t‐BuAAm/MA copolymerization, thus providing a tool for product and process optimization. The model structure can be used to support the development of other acrylate/acrylamide systems as part of the continued efforts to utilize "green" solvents to reduce the environmental impacts of polymerization processes. [ABSTRACT FROM AUTHOR]

Coordination‐insertion copolymerization of ethylene with polar monomers can directly provide value‐added functionalized polyolefins. Studies on the reactivity of catalysts toward polar monomers can help understand the copolymerization process and then tune the polymerization strategically. In this contribution, the reactivity picture of 2‐diphenylphosphonyl‐8‐phenylnaphthol nickel complex toward fundamental polar monomers was explored by stoichiometric reactions. The insertion rates are in the order of methyl acrylate (MA)>n‐butyl acrylate (BA)>N, N‐dimethylacrylamide (DMAA)>methyl methacrylate (MMA)>vinyl triethoxysilane (VTEoS)>N‐vinyl‐pyrrolidinone (NVP). Acrylic derivatives of MA, BA and DMAA with electron‐withdrawing group favor 2,1‐fashion while non‐acrylic NVP with electron‐donating group prefers 1,2‐fashion. Notably, the 1,1‐disubstituted MMA and bulky VTEoS perform a preferential 1,2‐insertion accompanying by 2,1‐insertion in the percentage of 82 : 18 and 62 : 38, respectively, because of the stronger steric effect. These insights correlate to the copolymerization of polar monomers with ethylene. Linear functional polyethylene with in‐chain and terminal incorporation of BA, DMAA or VTEoS is afforded at a high activity. [ABSTRACT FROM AUTHOR]

Increasing the interfacial adhesion with compatibilizer has been proved to be an effective method to enhance the mechanical properties of composites. In this paper, sodium methacrylate (NaMAA) was introduced to enhance the interfacial adhesion between polypropylene (PP) and ethylene propylene diene monomer (EPDM) via the peroxide‐induced dynamic vulcanization. NaMAA‐induced compatibilization enhanced the phase interface efficaciously and reduced the diameter of EPDM particles from ~8 to ~4 μm. Silica (SiO2) was used in the matrix to improve the mechanical properties of the thermoplastic vulcanizates (TPVs). It was found that SiO2 had little influence on the compatibility between EPDM and PP; however, it improved the tensile strength and stiffness of the TPVs without a severe reduction in the elasticity. The interfacial compatibility of modified EPDM/PP TPVs was verified by Fourier transform infrared, rubber process analyzer, and scanning electron microscope. With 3 wt% of NaMAA and 12 wt% of SiO2, the tensile strength improved from 8.5 to 12.7 MPa and the elongation at break was ranged from 320% to 410%. [ABSTRACT FROM AUTHOR]

[Display omitted] • MMIPs were synthetized based on MIP optimization for Enrofloxacin. • MMIPs were developed and used as dispersive-SPE sample preparation. • MMIPs devoted to diverse fluoroquinolone analysis in milk by LC-UV. The aim of the present study is to develop selective extracting materials applicable to a diversity of fluoroquinolones. A series of Molecularly Imprinted Materials (MIPs) were prepared in order to choose the nature of the monomer and that of the porogen together with its ratio with the cross-linker. A non-regulated quinolone, Levofloxacin, was used as a template to avoid false positive results in its application. The resulting MIPs were evaluated in MISPE experiments for Enrofloxacin. The polymer prepared using methyl acrylate (MA) as a monomer and MeOH/CHCl 3 (1:1, v/v) as a porogen provided the desired selectivity. Concretely, 100 μL (1.1 mmol) of MA as a monomer, 1.30 mL (9.8 mmol) of EGDMA (ethyleneglycol dimethacrylate) as a cross-linker, 31 mg (0.19 mmol) of AIBN (2,2′-azobis(2-methylpropionitrile)) as an initiator, were mixed with 85 mg (0.24 mmol) of levofloxacin as a template and 4 mL of MeOH/CHCl 3 (1:1, v/v) as a porogen. The obtained optimized composition was upgraded to magnetic molecularly imprinted polymers (MMIPs) to be used as a dispersive-SPE extracting materials in the analysis of fluoroquinolones in milk. The selectivity of the resulting material for several fluoroquinolones (enrofloxacin, ciprofloxacin, sarafloxacin and norfloxacin) was studied. Finally, the MMIP was tested against real quinolone positive milk samples to evaluate its applicability. [ABSTRACT FROM AUTHOR]

The kinetics and mechanism of benzoyl peroxide- and azobisisobutyronitrile-initiated polymerization of acrylic acid and methyl acrylate in the temperature range of 20–40°C have been investigated. In the case of evacuation of the monomer + initiator system, the polymerization proceeds without heating or other energetic impacts on the system. The polymer yield depends on the initiator concentration and the temperature and time of sample thermostating. It has been shown by EPR that the monomers affect the rate of initiator decomposition into radicals. The structures of intermediate complexes formed in the acrylic acid + azobisisobutyronitrile system have been determined by quantum-chemical calculations, and the activation energies of the relevant processes have been calculated. [ABSTRACT FROM AUTHOR]

Polymerization-induced self-assembly (PISA) is an efficient and versatile method to afford polymeric nano-objects with polymorphic morphologies. Compared to dispersion PISA syntheses based on soluble monomers, the vast majority of emulsion PISA formulations using insoluble monomers leads to kinetically-trapped spheres. Herein, we present aqueous emulsion PISA formulations generating worms and vesicles besides spheres. Two monomers with different butyl groups, n-butyl (nBHMA) and tert-butyl (tBHMA) α-hydroxymethyl acrylate, and thus possessing different water solubilities were synthesized via Baylis-Hillman reaction. Photoinitiated aqueous emulsion polymerizations of nBHMA and tBHMA employing poly(ethylene glycol) macromolecular chain transfer agents (macro-CTAs, PEG45-CTA, and PEG113-CTA) at 40 °C were systematically investigated to evaluate the effect of monomer structure and solubility on the morphology of the generated block copolymer nano-objects. Higher order morphologies including worms and vesicles were readily accessed for tBHMA, which has a higher water solubility than that of nBHMA. This study proves that plasticization of the core-forming block by water plays a key role in enhancing chain mobility required for morphological transition in emulsion PISA. [ABSTRACT FROM AUTHOR]

ARGET ATRP of methyl acrylate (MA) with low concentration of air stable-CuBr2 catalyst was successfully carried out in green solvent polyethylene glycol (PEG) without any external reducing agent. The polymerizations of MA proceeded in a well-controlled manner as evidenced by kinetic studies, chain extension results, a linear increase of the molecular weights with the increasing of monomer conversion. and narrow molecular weight distribution (Mw/Mn=1.1). Interestingly, we found that the PEG has the reduction ability to CuBr2 and could play as supplement reducing agent cooperation with Me6TREN to mediate ARGET ATRP. Reduction of Cu(II)Br2 to Cu(I)Br by different molecular weight PEG was proved by UV-visible spectroscopy. A.Q.-PEG with different molecular weight have strong effects on polymerization rate and the polymerization can be operated at suitable conditions where the use of catalyst concentration can decrease to 25 ppm level. [ABSTRACT FROM AUTHOR]

Extensive experimental results (measurements of the monomer conversion in the absence of any external initiators) indicating the occurrence of the self-initiation reaction of methyl acrylate (MA) at 120-220 °C are presented. To this date, for the MA, experimentally derived values of the rate coefficients of only propagation, termination, transfer to monomer, and transfer to polymer reactions have been reported. As MA and n-butyl acrylate (nBA) are from the same acrylate family, here, we exploit the family type behavior to obtain the rate coefficients of termination by mid-chain radicals and γ-Scission reactions of MA, on the basis of the rate coefficients of the same polymerization reactions of nBA. A new, simple, empirical, gel effect model is also presented. Using these rate coefficients and a macroscopic mechanistic polymerization reactor model, the rate coefficients of MA self-initiation and chain-transfer-to-monomer reactions as well as the parameters of the gel effect model are estimated from the MA conversion measurements. [ABSTRACT FROM AUTHOR]

The present work is focused on the γ-radiation induced polymerization of ethyl methacrylate (EMA) and methyl acrylate (MA) monomers mixture to obtain a co-polymer with specific features. The effect of the irradiation parameters (radiation absorbed dose, dose rate) and of the environmental atmosphere on the features of the final products was investigated. Attenuated Total Reflectance - Fourier Transform Infrared Spectroscopy (ATR-FTIR) and Nuclear Magnetic Resonance high-resolution analyses of hydrogen and carbon nuclei ( 1 H and 13 C NMR) were applied to follow the γ-induced modifications by monitoring the co-polymerization process and allowed the irradiation parameters optimization. Diffusion-Ordered NMR (DOSY-NMR) data were used to evaluate the co-polymers polydispersity and polymerization degree. Since the last parameter is strongly influenced by the γ radiation and environmental conditions, a comparison among samples prepared and irradiated in air and under nitrogen atmosphere was carried out. In presence of oxygen, higher radiation was required to obtain a full solid co-polymer since a partial amount of energy released to the samples was involved in competitive processes, i.e. oxygen-containing free radicals formation and primary radicals recombination. Irrespectively to the environmental atmosphere, more homogeneous samples in term of polymerization degree dispersion was achieved at lower dose rates. At radiation absorbed doses higher than those needed for the formation of the co-polymer, while in case of samples irradiated in air heavy depolymerization was verified, a sensible increase of the samples stability was attained if the irradiation was performed under nitrogen atmosphere. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiII complexes with symmetrical tetradentate Schiff-base ligands were prepared. • Four NiII complexes were applied in the photo-induced OMRP of vinyl acetate. • NiII complexes were able to control the polymerization under 390 and 400–800 nm LED irradiation. • Experimental and theoretical data suggest a majority reversible termination pathway. Four nickel(II) complexes with symmetrically substituted N 2 O 2 tetradentate Schiff-base ligands, prepared from the 2:1 condensation of 3- tert- butyl-salicylaldehyde, and ethylenediamine (1), o -phenylenediamine (2), 1,2-cis,trans -cyclohexyldiamine (3), or 1,3-diaminepropane (4), were synthesized. These NiII Schiff-base complexes (1 – 4) were used as control agents for the polymerization of vinyl acetate (VAc) photoinitiated by diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO) according to a photoinduced organometallic-mediated radical polymerization (photo-OMRP) mechanism. All complexes presented good control ability, although the polymerization mediated by 3 showed the best control over molecular weight (M n matching M n,th) and dispersity (Ð < 1.50). The livingness of the polymers has been confirmed by LED on and LED off experiments, the polymerization stopped immediately, and no monomer conversion was observed during the light-off period, indicating a negligible concentration of the active radical in the dark. Further, to demonstrate the living nature of this system, block copolymers of poly(vinyl acetate)- b -poly(methyl acrylate) were synthesized using the sequential visible-light-induced process. Kinetic results and computational investigations supported the activation/deactivation equilibrium exerted by complexes 1 – 4 , which occurred on only one face of the complexes via reversible deactivation (RD) mechanism. [ABSTRACT FROM AUTHOR]

This work investigated polyacrylonitrile copolymers synthesized using methyl acrylate (MA) and dimethyl itaconate (DMI) as second monomers by bulk polymerization in the presence of magnesium chloride as a reagent to control the tacticity of polyacrylonitrile copolymers. The copolymers synthesized by solution polymerization were used as a control group to study the tacticity effect. The C-NMR results confirm that the isotacticity by bulk polymerization is increased approximately double for either P(AN- co-MA) or P(AN- co-DMI). The X-ray diffraction (XRD) and the isothermal DSC results show that the P(AN- co-MA) produced by bulk process, as compared to that by solution polymerization, has higher domain size ( L ) and crystallinity (CI); moreover, its cyclization period is decreased significantly. It indicates that the increase of isotacticity for P(AN- co-MA) makes the crystalline domain larger and the cyclization takes place more easily. However, such positive correlations do not hold good for the P(AN- co-DMI) system. It is due to the high steric-hindrance effect for the DMI monomer, which has long reactive branches on both sides of the vinyl DMI monomer, complicating the mechanisms of crystallization and cyclization and resulting in diminishing the contribution of high isotacticity to lower the barrier of cyclization reaction. [ABSTRACT FROM AUTHOR]

This review encompasses the fundamentals of kinetics of atom transfer radical polymerization (ATRP). ATRP is a versatile reversible-deactivation radical polymerization (RDRP) technique, frequently utilized to synthesize advanced functional materials. Detailed mechanistic investigations over the past two decades allowed for an in-depth understanding of the underlying processes and rational design of the reaction conditions. Various aspects of ATRP kinetics are reviewed such as initiation modes, methods allowing to decrease catalyst concentration, influence of the initiator, catalyst (transition metal, ligand, counterion), solvent, additives, type of monomer, and effect of temperature and pressure. Techniques utilized to determine kinetic parameters of catalytic systems are discussed. Finally, guidelines for synthesis of polymers with targeted architectures, predetermined molecular weights, narrow molecular weight distributions, and high retained chain end functionality are presented. [ABSTRACT FROM AUTHOR]

Due to increasing environmental concern regarding detrimental effects of organic solvents, a new post-metallocene titanium-based catalyst [TiLCl] { LH =2-(3,5-Di-tert-butyl-2-hydroxy-benzylamino)-succinamic acid} with sidearm approach has been synthesized for aqueous emulsion polymerization of olefins. The catalyst has been characterized by elemental analysis, H NMR, C NMR, HRMS, IR, and UV-visible spectroscopy. The catalyst is easy to synthesize and is moderately stable in water. In aqueous emulsion, in the presence of co-catalyst NaBPh, it has been found to exhibit moderate to high activity in the range of 10 to produce homopolymers and copolymers of methyl acrylate and methyl methacrylate which are widely used for a variety of applications. The influence of the main reaction parameters on the polymerization reactions at room temperature was studied including the catalyst/co-catalyst ratio, type of monomers, reaction time, etc. Structures and properties of the obtained polymers were analyzed by various instrumental techniques like differential scanning calorimetry (DSC), gel permeation chromatography (GPC), H NMR, C NMR, etc., as well as by various experimental methods. The results indicated that the PMMA and PMA produced by the newly synthesized catalytic system are syndiotactic rich and possess ultrahigh-viscosity average molecular weight in the order of 10 g/mol. [ABSTRACT FROM AUTHOR]

Branched amphiphilic copolymers weresynthesized through the reversibleaddition–fragmentation chain transfer (RAFT) chain extensionof a poly(methyl acrylate) macro-chain transfer agent using a protectedgalactose monomer and a polymerizable chain transfer agent branchingunit. After galactose deprotection, the copolymers were self-assembledvia nanoprecipitation. The resultant nanoparticles were analyzed fortheir size, shape, and biological interaction with a galactose bindinglectin. Using light scattering, the nanoparticles were determinedto be solid spheres. Nanoparticles containing branched glycoblocksbound significantly more lectin than those containing comparable linearblocks. By adjusting the molecular weight and branching of the copolymer,the size of the self-assembled nanoparticle and the saccharide densityon its surface can be varied. [ABSTRACT FROM AUTHOR]

Reversible addition–fragmentationtransfer (RAFT) polymerizationof a η5-cyclopentadienylcobalt-η4-cyclobutadiene (CpCoCb) containing monomer under a wide varietyof experimental conditions (e.g., different solvents, temperatures,RAFT agents, concentrations, and [RAFT agent]/[initiator]) was examined.In all cases the results revealed that although the monomer was beingconsumed over the course of the reaction, there was no significantincrease in the molecular weight of the resulting polymer. It wasdetermined that as the polymer chain grows (DP ≈ 10), a tightcoil morphology was adopted, which hinders the approach of an additional,sterically demanding CpCoCb-containing monomer. This resulted in prematuretermination/chain transfer reactions rather than an increase in thepolymer chain length. To address this problem, methyl acrylate (MA)with its lower steric demand was copolymerized with the bulky CpCoCb-containingmonomer to act as a spacer. This provided the necessary steric reliefand an opportunity for the metallopolymer to grow. This copolymerizationresulted in dramatic improvements in the polydispersity and molecularweight of the end material. In subsequent experiments, the randomcopolymer was used as a macro-RAFT agent to prepare diblock copolymers,with good control over the molecular weight, allowing for an examinationof the self-assembly behavior of the block copolymer in the solidstate. [ABSTRACT FROM AUTHOR]

With oleic acid grafting modification, a series of hyperbranched-linear polymer surfactants (HLPS) were prepared by hydroxyl-terminated hyperbranched polymer (HBP), which was gained through a step synthesis method using trimethylolpropane and AB monomer. The AB monomers were obtained through the Michael addition reaction of methyl acrylate and diethanol amine. The structures of HLPS were characterised by Fourier transform infrared spectrophotometer and nuclear magnetic resonance (NMR), which indicated that HBP was successfully modified by oleic acid. Furthermore, the properties of surface tension and critical micelle concentration of HLPS solution showed that HLPS can significantly reduce the surface tension of water. The morphology of the HLPS solution was characterised by dynamic light scattering, which revealed that HLPS exhibited a nonmonotonic appearance in particle size at different scattering angles owing to the different replaced linear portions. The relationships of the surface pressure to monolayer area and time were measured using the Langmuir-Blodgett instrument, which showed that the surface tension of monolayer molecules increased with the increasing of hydrophobic groups. In addition, the interface conditions of different replaced HLPS solutions were simulated. [ABSTRACT FROM AUTHOR]

Abstract: Methyl acrylate (MA) monomer was grafted onto ultra-high molecular weight polyethylene (UHMWPE) fibers by γ-ray pre-irradiation induced graft polymerization. The grafting of MA on UHMWPE fiber was confirmed by thermogravimetric analysis and Fourier-transform infrared spectroscopy. The degree of grafting (DG) increased with an increase in absorbed dose and reached a significantly high value (approximately 200%) at 100kGy. Scanning electron microscopy analysis revealed that the surface of the UHMWPE-g-PMA fibers was covered by the MA grafting layer and became rough. The monoclinic crystalline and orientated intermediate phases were disordered by the grafting chains such that degree of orientation declined gradually with increasing DG. The tensile strength of UHMWPE-g-PMA fiber decreased with increasing dose but was independent of DG, whereas the fiber modulus declined with DG. UHMWPE-g-PMA fiber that possesses desirable mechanical properties could be obtained at a dose of less than 10kGy. [Copyright &y& Elsevier]

In this paper, graft-copolymerization of Hibiscus sabdariffa (Roselle) using methyl acrylate (MA) as principal monomer and 4-vinyl pyridine (4-VP) as secondary monomer, using eerie ammonium nitrate- nitric acid initiator system in binary vinyl monomeric mixture, has been reported. Different optimized reaction parameters such as temperature, time, initiator concentration, monomer concentration and pH were used to obtain the maximum graft yield and then to explore its change on properties and behaviour of the fibre. The graft copolymer were characterized by FT1R, SEM, XRD, TGA and DTA techniques and evaluated for swelling behaviour, chemical resistance, moisture absorbance and dye-uptake behaviour, keeping in view the use of these advanced graft copolymers for scientific and industrial application. [ABSTRACT FROM AUTHOR]

Abstract: Immobilized cutinase HiC from the ascomycete Humicola insolens was applied as a novel biocatalyst for the synthesis of functionalized acryclic esters by transesterification. As a model reaction, transesterification of methyl acrylate with 6-mercapto-1-hexanol at a high molar ratio in a solvent free system was chosen. Besides two minor Michael-addition by-products, 6-mercaptohexyl acrylic ester was identified as the main product with the thiol as the functional end group. Reaction conditions were optimized regarding the influence of water (0–1.72M), temperature (22–50°C), product inhibition and addition of the radical inhibitor butylated hydroxytoluol (BHT; 0.14–0.71M) on conversion and by-product formation. Highest conversion of 6-mercapto-1-hexanol to 6-mercaptohexyl acrylic ester (95.4±0.3%) was achieved after 6h at 40°C in the presence of 0.025% (w/w) water without formation of by-products in a solvent free system. Applying methyl methacrylate, transesterification with 6-mercapto-1-hexanol was significantly lower (43.6±0.1%) compared to transesterification of methyl acrylate with 6-mercapto-1-hexanol. [Copyright &y& Elsevier]

This paper presents a systematic computational studyof the mechanism of cyclohexanone–monomer co-initiation inhigh-temperature homopolymerization of methyl acrylate (MA) and methylmethacrylate (MMA). Previous experimental studies of spontaneous thermalhomopolymerization of MA and MMA showed higher monomer conversionin the presence of cyclohexanone than xylene. However, these studiesdid not reveal the initiation mechanism(s) or the initiating species.To identify the initiation mechanism and the initiating species, weexplore four different mechanisms, (1) Kaim, (2) Flory, (3) α-positionhydrogen transfer, and (4) Mayo, using first-principles density functionaltheory (DFT) and second-order Møller–Plesset perturbationtheory (MP2) calculations. Transition-state geometries for each mechanismare determined using B3LYP/6-31G* and assessed with MP2/6-31G*. Activationenergies and rate constants are calculated using transition-statetheory. The harmonic oscillator approximation and tunneling correctionsare applied to compute the reaction rate constants. This study indicatesthat α-position hydrogen transfer and Mayo mechanisms have comparablebarriers and are capable of generating monoradicals for initiatingpolymerization of MA and MMA; these two mechanisms can cause cyclohexanone–monomerco-initiation in thermal polymerization of MA and MMA. [ABSTRACT FROM AUTHOR]

In this study, an acrylate monomer containing two hydroxyl groups, 2,2-bis(hydroxymethyl)butyl acrylate (HBA), was successfully synthesized by acidic hydrolysis of the monomer precursor, (5-ethyl-2,2-dimethyl-1,3-dioxane-5-yl)methyl acrylate (EDMA), which was prepared by esterification reaction between 2,2-dimethyl-5-ethyl-5-hydroxymethyl-1,3-dioxane and acryloyl chloride. Subsequently, poly(HBA) containing pendant diol group was prepared either by direct reversible addition-fragmentation chain transfer (RAFT) polymerization of HBA or by RAFT polymerization of EDMA, followed by deprotection. The RAFT polymerization of both monomers was performed in dioxane using 2-(ethylthiocarbonothioylthio)-2-methyl propanoic acid (EMP) as the RAFT agent and 2,2′-azobis(isobutyronitrile) (AIBN) as the initiator. Kinetic studies demonstrated that the polymerization process of both monomers followed pseudo first-order kinetics with respect to the monomer concentrations. The molecular weight of the resulting polymer increased linearly with monomer conversion, while a low polydispersity was maintained throughout. [ABSTRACT FROM AUTHOR]

The structures of the “Z” and “R”substituentsof a RAFT agent (Z–C(S)S–R) determine a RAFT agent’sability to control radical polymerization. In this paper we reportnew acid/base switchable N-aryl-N-pyridyl dithiocarbamates (R = −CH2CN, Z = −N(Py)(Ar))which vary in substituent at the 4-position of the aryl ring and theuse of these to control molecular weight and dispersity. In theirprotonated form, the new RAFT agents are more effective in controllingpolymerization of the more activated monomer, methyl acrylate (MA),whereas in their neutral form they provide more effective controlof the polymerization of less activated monomers, N-vinyl carbazole (NVC) and vinyl acetate (VAc). For each polymerization,the apparent chain transfer coefficient (Ctrapp) shows a good correlation with Hammett parameters.Dithiocarbamates with more electron-withdrawing aryl ring substituentshave the higher Ctrapp. Thisdemonstrates the influence of polar effects on Ctrappand supports the hypothesis that the activityof these RAFT agents is determined by the availability of the lonepair of the dithiocarbamate nitrogen. [ABSTRACT FROM AUTHOR]

8-methacryloxy-quinoline monomer (MAQ) was prepared by the reaction of 8-hydroxyquinoline with either methacryloyl chloride or methacrylic acid in the presence of triethylamine and N, N′-dicyclohexylcarbodiimide, respectively. Its structure was confirmed by IR and 1 H-NMR spectroscopy. Binary copolymerization of this new monomer with methyl acrylate (MA), acrylonitrile (AN) methyl methacrylate (MMA), styrene(ST), were performed in Dimethylformamide, using 1 mol% azobisisobutyronitrile as initiator at 65 °C. The copolymer compositions were determined from nitrogen analysis except MAQ-AN with 1 H-NMR. Copolymerization Parameters for each system were calculated by both the Finemen-Ross and Kelen-Tüdös methods. The monomer reactivity ratios for the systems MAQ-MA, MAQ-AN, MAQ-MMA and MAQ-ST were found to be r1 = 0.695 ± 0.036, r2 = 0.62 ± 0.235; r1 = 0.273 ± 0.087, r2 = 0.259 ± 0.67; r1 = 0.356 ± 0.015, r2 = 1.615 ± 0.052 and r1 = 0.097 ± 0.003, r2 = 0.339 ± 0.027 respectively. The Q and e values for MAQ monomer were found to be 1.62 and 1.40. [ABSTRACT FROM AUTHOR]

In this paper, the thermal and chemical changes in Hibiscus sabdariffa stem fiber on graft copolymerization with methyl acrylate (MA) and acrylonitrile (AN) monomer, using a ceric ammonium nitrate – nitric acid initiator system, has been reported. Different reaction parameters such as temperature, time, initiator concentration, monomer concentration, and pH were optimized to get the maximum graft yield. The graft copolymer thus formed was characterized by FTIR, SEM, TGA, DTA, and XRD techniques. The swelling behavior of graft copolymers in methanol, n-butanol, water and di methyl formamide was studied and screened for dye uptake behavior in 0.1% gentian violet dye for seven hours. With increase in percentage grafting the percentage crystallinity, crystallinity index, and moisture absorbance were found to decrease whereas chemical resistance (against 1 N HCl and 1 N NaOH) and thermal resistance were found to increase for its various advanced applications. [ABSTRACT FROM AUTHOR]

Jute fabrics were modified with methyl acrylate (MA), ethyl acrylate (EA), and 2-hydroxyethyl acrylate (2-HEA) using UV radiation at different periods of time. It was found that 30% MA at 60 min, 15% EA at 40 min, and 15% 2-HEA at 15 min irradiation time in methanol along with photoinitiator showed the best results. Some additives, such as urea, acrylamide (AM), ethylhexyl acrylate (EHA), tripropelene glycol diacrylate (TPGDA), and trimethylol propane triacrylate (TMPTA), were incorporated into the optimized monomer solutions and monitored its effect on the properties. Various physico-mechanical properties of both treated and untreated jute fabrics were also performed. [ABSTRACT FROM AUTHOR]

Various reaction parameters for the graft copolymerization of Hibiscus sabdariffa fiber with methyl acrylate, ethyl acrylate, butyl acrylate, and acrylonitrile monomer were optimized using ceric ammonium nitrate-nitric acid as initiator system. The graft copolymers thus obtained were characterized by SEM, FT-IR, and XRD. Their evaluation and X-ray diffraction studies revealed change in morphology of the grafted fiber. The percentage crystallinity and crystallinity index were found to decrease with increase in percentage grafting, however, the cellulose I form remains unchanged in the fiber after graft copolymerization, under the optimized reaction conditions. [ABSTRACT FROM AUTHOR]

Abstract: Novel water-compatible molecularly imprinted polymers were synthesized in methanol–water systems with Tratarzine as template and 1-(α-methyl acrylate)-3-methylimidazolium bromide (1-MA-3MI-Br) as functional monomer, which has π–π hydrophobic, hydrogen-bonding and electrostatic interactions with template molecule. 1-MA-3MI-Br molecularly imprinted polymers (1-MA-3MI-Br-MIPs) were used as selective sorbents for the solid-phase extraction (SPE) of water-soluble acid dyes from wastewater and soft drink. The good linearity of the method was obtained in a range of 5.0–2000μg/L with the correlation coefficient of >0.999. The detection limits were in a range of 0.13–0.51μg/L for the water-soluble acid dyes in wastewater and 0.095–0.84μg/L for those in soft drink. The mean recoveries for the acid dyes are from 89.1% to 101.0% in spiked wastewater and 91.0–101.3% in spiked soft drink. Compared with strongly anion exchange solid phase extraction (SAX-SPE), mixture anion exchange solid phase extraction (MAX-SPE), and 1-MA-3MI-Br non-imprinted solid phase extraction (1-MA-3MI-Br-NISPE), almost all of the matrix interferences were removed by 1-MA-3MI-Br-MISPE, exhibiting higher selectivity, recovery and enrichment ability for the acid dyes and better baselines in the results of HPLC analysis. [Copyright &y& Elsevier]

Methyl acrylate (MA) monomer was graft copolymerized onto Hibiscus sabdariffa stem fiber and used to explore the additive effect of vinyl acrylate (VA) and ethyl acrylate (EA) on percentage grafting and the properties of the fiber, in binary vinyl monomeric mixtures. The graft copolymers were reinforced into phenol-formaldehyde polymer matrix to form biocomposites and characterized by FTIR, XRD, TGA, DTA, and SEM techniques. They were evaluated for physico-chemical changes in properties like moisture absorption at different relative humidity levels and chemical resistance against 1N NaOH and 1N HCl. These graft copolymers-reinforced biocomposites had higher mechanical strength like hardness, modulus of rupture, modulus of elasticity, and stress at the limit of proportionality. These novel materials can have numerous scientific and industrial applications for the development of technology. [ABSTRACT FROM AUTHOR]

Acrylic resin monomers, especially acrylates and methacrylates, are important occupational allergens. To analyse patterns of concomitant patch test reactions to acrylic monomers in relation to exposure, and to suggest possible screening allergens. We reviewed the patch test files for the years 1994-2009 at the Finnish Institute of Occupational Health for allergic reactions to acrylic monomers, and analysed the clinical records of sensitized patients. In a group of 66 patients allergic to an acrylic monomer, the most commonly positive allergens were three methacrylates, namely ethyleneglycol dimethacrylate (EGDMA), 2-hydroxyethyl methacrylate (2-HEMA) and 2-hydroxypropyl methacrylate (2-HPMA), and an acrylate, namely diethyleneglycol diacrylate (DEGDA). The patterns of concomitant reactions imply that exposure to methacrylates may induce cross-reactivity to acrylates, whereas exposure to acrylates usually does not lead to cross-allergy to methacrylates. Screening for triethyleneglycol diacrylate (TREGDA) in the baseline series was found to be useful, as 3 of 8 patients with diagnosed occupational acrylate allergy might have been missed without the screening. A short screening series of four allergens, EGDMA, DEGDA, 2-HPMA and pentaerythritol triacrylate (PETA), would have screened 93% of our 66 patients; each of the remaining 5 patients reacted to different acrylic monomer(s). [ABSTRACT FROM AUTHOR]

Synthesis of methylated oligopropylamines by the stepwise repetition of reactions between methyl acrylate and amine, amidation and reduction of the resulting amide is reported. Long-chain oligomers (average 15 nitrogen atoms) were obtained via condensation reactions utilising 1,3-dibromopropane. Three new acrylic monomers were prepared by reaction of oligopropylamines with acryloyl chloride. The synthesized amines and monomers are promising as model compounds for biosilicification reactions, as biologically active substances and as building blocks in organic and polymer chemistry. [ABSTRACT FROM AUTHOR]

The Cu(0)/Me6‐TREN‐catalyzed single‐electron transfer mediated living radical polymerization (SET‐LRP) of methyl acrylate in the presence of the classic 4‐methoxyphenol free radical inhibitor was investigated. Kinetic experiments, combined with 1H NMR, and MALDI‐TOF MS analysis of the resulting polyacrylates demonstrated that SET‐LRP is a robust synthetic method that does not require the purification of the monomers to remove the radical inhibitor. It is anticipated that these results will contribute to the expansion of technological and fundamental applications of SET‐LRP since it allows the synthesis of polymers with a structural perfection that previously was not accessible by any other method, starting from unpurified monomers, solvents, initiators, and ligands. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3174–3181, 2008 [ABSTRACT FROM AUTHOR]

Graft copolymerization of methyl acrylate (MA) onto OPEFB fiber has been successfully carried out using hydrogen peroxide and ferrous ammonium sulfate as initiators in an aqueous medium. The effects of reaction temperature, reaction period, and amount of monomer and initiators on the percentage of grafting were investigated. The results show that the percentage of grafting depends on reaction period and temperature as well as concentration of monomers and initiators. With 33.36 mmol of MA, the optimum percentage of grafting was obtained when the reaction was carried out using 6.00 mmol of H2O2 and 0.191 mmol of Fe2+ for 210 min at 75°C. The presence of the functional group in the grafted polymers was characterized by FTIR spectroscopy. Scanning electron microscopy was used to study the surface morphology. Thermogravimetric analysis indicated that the grafted OPEFB is thermally stable than the OPEFB [ABSTRACT FROM AUTHOR]

Atom transfer radical bulk copolymerization of MA and MMA was performed in the presence of CuCl/PMDETA as catalyst system and trichloromethyl-terminated poly(vinyl acetate) macroinitiator at 80°C. The overall monomer conversion was followed gravimetrically and chemical composition of the copolymer was determined by 1H-NMR spectrometry. The results have been used to calculate monomer reactivity ratios by linear and nonlinear methods. Reactivity ratios calculated were in the range of 0.3766-0.4988 and 1.8832-2.0963 for MA and MMA, respectively. These values were in good agreement with the values reported for a similar system in the free radical copolymerization. It was observed that the copolymerization system tends to produce a random copolymer with longer sequences of MMA than MA in the initial stage of polymerization before any significant decrease of the concentration of MMA in the monomer mixture. Copolymer microstructures in this study indicated that radical stabilization capability of MMA compared to MA is higher. The accuracy of the reactivity ratios were confirmed by 95% joint confidence limits. It was found that considering the effect of conversion in these methods makes the calculation result more accurate. The theoretical composition drifts in the comonomer mixture and copolymer as a function of the overall monomer conversion are also reported. [ABSTRACT FROM AUTHOR]

Abstract: The feasibility of radical copolymerization of β-pinene and methyl acrylate (MA) was clarified for the first time. The monomer reactivity ratios were evaluated by Fineman–Ross, Kelen–Tudos and non-linear methods, respectively. The obtained values were r β-pinene ∼0 and r MA ∼1.3, indicating that the copolymerization led to polymers rich in methyl acrylate units and randomly alternated by single β-pinene unit. The addition of Lewis acid Et2AlCl to the AIBN-initiated copolymerization enhanced the incorporation of β-pinene. Furthermore, the possible controlled copolymerization of β-pinene and MA was then attempted via the reversible addition–fragmentation transfer (RAFT) technique. The copolymerization (f β-pinene =0.1) using 1-methoxycarbonyl ethyl dithiobenzoate (MEDB) as a RAFT agent gave copolymers with lower molecular weight and narrower molecular weight distribution. However, the presence of MEDB strongly retarded the copolymerization. Thus a new RAFT agent 1-methoxycarbonyl ethyl phenyldithioacetate (MEPD), which gives a less stable macroradical intermediate than MEDB, was synthesized and introduced to the copolymerization. As anticipated, a much smaller retardation was observed. Moreover, the copolymerization displayed a somewhat controlled features within a certain overall conversion (<∼40%). [Copyright &y& Elsevier]

Finishing kinetics of acrylic precursor fibers was studied by using a new CGB-1 finish. Effects of different comonomers including vinyl pyrrolidone, acrylamide and methyl acrylate on finishing behavior of acrylic precursors were discussed. Diffusion coefficients of the finish were calculated by the Crank’s equation. It is shown that the precursor fibers with the CGB-1 finish do not have fluff, broken and adhered precursors. The increase of the finish uptake is greater around the glass-transition temperature and the change of uptake becomes less prominent as the finish bath temperature is above the glass-transition temperature. By use of comonomers, the finish uptake is enhanced, the diffusion coefficient of the finish is higher, the activation energy required for the finish is lower and the extent of decrease is the greatest for the fibers containing vinyl pyrrolidone. The properties of the finished precursor fibers containing polyvinyl pyrrolidone are the best. [ABSTRACT FROM AUTHOR]

Reactions of Ru 5 (CO) 15 (μ 5 -C), 1 with the polar vinyl monomers (PVM), methyl acrylate, vinyl acetate and N,N-dimethylacrylamide proceed by cluster opening additions accompanied by CH activation in the vinyl group of the PVM to yield olefin-activated complexes such as Ru 5 (μ 5 -C)(CO) 14 [η2-O CO(Me)CH CH](μ-H), 2 , Ru 5 (μ 5 -C)(CO) 14 [η2-(MeCO 2)C CH 2 (μ-H), 3 and Ru 5 (μ 5 -C)(CO) 14 [η2-O C(NMe 2)CH CH](μ-H), 6. In this work we have investigated the nature of the addition and coupling/cross-coupling of a second PVM to the CH activated PVM in the complexes 2 , 3 , and 6. The products consist of C–C coupled diolefin complexes that have been transformed into η3-allyl ligands by shifts of the hydrogen atoms in the C–C coupled ligands. Nine new complexes of Ru 5 (μ 5 -C)(CO) 13 [η3-1- anti , 3- anti -(MeO)C O–C 3 H 3 -η1-O C(OMe)CH 2 (μ-H), 8 ; Ru 5 (μ 5 -C)(CO) 13 [η3-1- anti , 3- syn -(MeO 2 C)CH 2 C 3 H 3 –CH 2 -η1-O C(OMe)](μ-H), 9 ; Ru 5 (μ 5 -C)(CO) 12 [μ-η3-O C(OMe)CH CH][η2-CH CHCO 2 Me](μ-H), 10 ; Ru 5 (μ 5 -C)(CO) 13 [η3-1- syn , 3- anti -(MeO 2 C)C 3 H 3 -η1-O C(OMe)CH 2 (μ-H), 11 ; Ru 5 (μ 5 -C)(CO) 13 [η3-1- syn , 3- anti -Me 2 NC O–C 3 H 3 -η1-O=CNMe 2 CH 2 (μ-H), 12 ; Ru 5 (μ 5 -C)(CO) 13 [η3-1- anti , 3- syn -(Me 2 N)C(=O)–C 3 H 3 –CH 2 -η1-O C(NMe 2)](μ-H), 13 ; Ru 5 (μ 5 -C)(CO) 12 [μ-η3-O C(NMe 2)CH CH][η2-CH CHCO 2 Me](μ-H), 14 ; Ru 5 (μ 5 -C)(CO) 13 [η3-1- anti , 3- syn -MeO 2 CCH 2 C 3 H 3 -η1-O C(NMe 2)](μ-H), 15 , and Ru 5 (μ 5 -C)(CO) 12 [μ-η2-(MeO 2 C)CH CH][η3-CH 2 CHOC(=O)Me)](μ-H), 16 have been obtained and structurally characterized. Three of these complexes (10 , 14 and 16) contain uncoupled olefin ligands. Image 1 • C–H activation combined with C– C coupling of polar vinyl monomers by a Ru 5 cluster complex. • C–C coupling of methylacrylate and dimethylacrylamide by a Ru 5 cluster complex. • C–H activation in vinyl acetate by a Ru 5 cluster complex. [ABSTRACT FROM AUTHOR]

Palladium N,N'-bis(3-allylsalicylidene)o-phenylenediamine complex (PdAS) immobilized onto mesoporous polymeric methyl acrylate (MA) based resins (PdAS(x)-MA, x = 1, 2, 5, or 10 wt.%) were successfully prepared as heterogeneous catalysts for the Heck reaction. The catalysts were synthesized via radical suspension polymerization using PdAS as a metal chelate monomer, divinylbenzene and MA as co-monomers. The effect of the PdAS(x) content on the physicochemical properties of the resins is also reported. The catalysts were characterized by using a range of analytical techniques. The large surface area (>580 m2·g−1) and thermal stability (up to 250 °C) of the PdAS(x)-MA materials allows their application as catalysts in the C–C coupling reaction between iodobenzene and MA in the presence of trimethylamine at 120 °C using DMF as the solvent. The PdAS(10)-MA catalyst exhibited the highest catalytic performance with no significant catalytic loss being observed after five reuses, thereby indicating excellent catalyst stability in the reaction medium. [ABSTRACT FROM AUTHOR]

The peculiarities of controlled copolymerization of acrylonitrile with methyl acrylate and dimethyl itaconate in the presence of copper-based catalytic system were investigated. It was shown that the polymerization proceeds in a controlled mode in accordance with ARGET ATRP mechanism. The increase of molecular weights in a strict agreement with theoretically predicted values is observed. The formation of copolymers was confirmed by NMR and MALDI TOF MS analysis. The introduction of mentioned monomers to acrylonitrile results in slight decrease of the polymerization rate. The performed calorimetric investigations showed the smoothing of exothermic effect of the oxidative stabilization of formed copolymers. [ABSTRACT FROM AUTHOR]

With the purpose of modifying organic fluorescent dyes based on the coumarin scaffold, and developing and evaluating a route to its incorporation into a polymeric backbone, a study was conducted on the co-polymerization of 3-vinylcoumarins with styrene and methyl acrylate using 2,2-azobis(isobutyronitrile) (AIBN) as the radical initiator. The structural and photophysical characterization proved the incorporation of the coumarin monomers into the polymeric chain and further showed a decrease in the fluorescence quantum yields in the co-oligomers. [ABSTRACT FROM AUTHOR]