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New amphiphilic block copolymers on based benzylmethacrylates or 2,3,4,5,6-pentafluorobenzyl methacrylate and N-isopropylacrylamide with high yields (89–94%) and MM 1.2∙105 and 1.63∙105 were synthesized. The relative constants of chain transfer to tris-(pentafluorophenyl)germanium during the radical polymerization of 2,3,4,5,6-pentafluorobenzyl methacrylate and benzylmethacrylate were 1.26 and 0.45, respectively. The structure of the copolymers was confirmed by IR and NMR spectroscopy. By the method of TGA analysis, the temperature of the beginning of decomposition of polymers was established, which amounted to 228.2 ºC and 150 ºC for the fluorinated and non-fluorinated block copolymer, respectively. The properties of polymers in solutions were studied by GPC, molecular hydrodynamics and optics. For both fluorinated and non-fluorinated samples, only macromolecules were observed in dilute solutions. The behavior of a non-fluorinated sample was well described as a coil in a good solvent, while fluorinated macromolecules were characterized by a compressed coil conformation, due to the presence of fluorine in the polymer structure. It was shown that the block copolymers formed stable Langmuir monolayers with high surface pressures (50–58 mN/m), and the transferred Langmuir–Blodgett films on silicon wafers were hydrophilic (water contact angles are 68–73 ºC). A large hysteresis loop on the surface pressure isotherm obtained under compression-expansion conditions for a fluorinated block copolymer indicates significant inter- and intramolecular interactions at the water–air interface. [ABSTRACT FROM AUTHOR]

In the present work, a family of functionalized statistical copolymers was synthesized by radical polymerization from a varied composition of benzyl methacrylate (BzMA) and N,N-dimethylaminoethyl methacrylate (DMAEMA) comonomers using 2,2'-azobisisobutyronitrile (AIBN) as initiator. The characterization, identification, and composition analysis of each copolymer were carried out by spectroscopic methods (FTIR and 1H-NMR). Then, different properties were evaluated: molecular size was determined by measurement of intrinsic viscosity [η] in THF at 25 °C and glass transition temperature (Tg) analyzed by differential scanning calorimetry. Films were prepared by the solvent casting method from selected samples with different compositions and their mechanical properties were analyzed by tensile tests. It was observed that the composition of the functionalized copolymers substantially affects their macromolecular and mechanical properties, evidencing greater flexibility when the DMAEMA content in the copolymer increased. [ABSTRACT FROM AUTHOR]

The silicone modified acrylate dispersion was successfully prepared by semi-continuous seed emulsion polymerization, in which methyl methacrylate (MMA) was used as a hard monomer, butyl methacrylate (BA)was used as a soft monomer, and a double bond-containing polymerizable emulsifier ammonium allyloxtmethylate nonylphenol ethoxylates sulfate (DNS-86)and potassium persulfate (KPS)were utilized as emulsifiers and initiators, respectively. A functional monomer, benzyl methacrylate (BZMA), and a modified monomer, vinyltriethoxysilane (VTES), were introduced into the base dispersion. The factors, which have an influence on emulsion polymerization performance, were optimized. At the same time, the dispersions prepared with conventional emulsifiers and polymerizable emulsifiers were compared under the same conditions. The structure and properties of the synthetic dispersion were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and contact angle (CA). The results showed that the optimum preparation conditions of the dispersion are as follows: The amount of emulsifier was 3%, the amount of initiator was 0.5%, main monomer ratio was 1:1, the amount of functional monomer BZMA and VTES was 3%, respectively. The dispersion obtained by using DNS-86 had better thermal stability, chemical stability and the dispersion was uniformly blue, which represented small particle size. After modification, the film showed higher hydrophobicity. [ABSTRACT FROM AUTHOR]

Statistical copolymers of N-vinylpyrrolidone (NVP) with benzyl methacrylate (BzMA) were prepared by Reversible Addition-Fragmentation chain Transfer Polymerization (RAFT), employing three different xanthates as RAFT agents: [(O-ethylxanthyl)methyl]benzene, [1-(O-ethylxanthyl)ethyl]benzene and O-ethyl S-(phthalimidylmethyl) xanthate. The reactivity ratios were estimated using the Fineman-Ross, inverted Fineman-Ross, Kelen-Tüdos and extended Kelen-Tüdos linear graphical methods, as well as the computer program COPOINT. Structural parameters of the copolymers were obtained by calculating the dyad sequence fractions and the mean sequence length. All the methods are in agreement that the probability for the incorporation of BzMA units is much greater than for that of NVP units. The glass-transition temperature (Tg) values of the copolymers were measured by Differential Scanning Calorimetry and examined by means of several theoretical equations, allowing for the prediction of theseTg values. Subsequently, a systematic and detailed investigation of the thermal degradation of these copolymers compared with that of the respective homopolymers, was carried out by Thermogravimetric Analysis, within the framework of the Ozawa-Flynn-Wall and Kissinger methodologies. As expected, the thermal stability of the copolymers is influenced by the structure of the substituents of the thiocarbonylthio end groups due to the RAFT agents. [ABSTRACT FROM PUBLISHER]

A composite of multi-walled carbon nanotubes incorporated into a benzyl methacrylate- co -ethylene dimethacrylate porous monolith was prepared, characterized and used as solid phase adsorbent and as stationary phase for simultaneous extraction and separation of ten polycyclic aromatic hydrocarbons, followed by nano-liquid chromatography analysis. The extraction and chromatographic parameters were optimized with regard to the extraction efficiency and the quality of chromatographic analytes separation. Under the optimized conditions, all PAHs were separated in 13 min with suitable resolution values (Rs = 1.74–3.98). Addition of a small amount of carbon nanotubes (0.1% with respect to monomers) to the polymerization mixture increased the efficiency for the separation column to over 41,700 plates m −1 for chrysene at flow rate of 0.5 μL min −1 . The method showed a wide linear range (1–500 μg L −1 with R 2 more than 0.9938), acceptable extraction repeatability (RSDs < 6.4%, n = 3) and reproducibility (RSDs < 12.6%, five parallel-made solid phase extraction cartridges) and satisfactory detection limits (0.02–0.22 μg L −1 ). Finally, the proposed method was successfully applied to the detection of polycyclic aromatic hydrocarbons in environmental water samples. After a simple extraction procedure with preconcentration factor equal to 100, the average recovery values in ultra-pure, tap and sea water samples were found to be in the range 81.3–95.4% with %RSD less than 6.4. Again, the presence of carbon nanotubes (0.3% relatively to monomers) in native polymer enhanced the extraction performance for the solid phase adsorbent up to 78.4%. The application of the monoliths modified with CNTs in extraction and nano-scale liquid chromatography for analysis of environmental samples offered several advantages; it demonstrated an acceptable precision, low detection limits, good reproducibility, satisfying recoveries and wide dynamic linear ranges. [ABSTRACT FROM AUTHOR]

A schematic representation of pyrolysis and oxidative decomposition paths of poly(geranyl methacrylate)- co -poly(benzyl methacrylate) copolymers (GM- co -BM) using a simultaneous TG/FTIR/QMS analysis has been evaluated, for the first time. The tested polymers are more environmentally friendly, high chemical and solvent resistant materials with a glass transition temperature below 47 °C. Their pyrolysis took place in one main stage visible from 220 °C± 3–245 °C± 2–440–500 °C, depending on their composition. The pyrolysis was connected with the emission of benzyl methacrylate, methacrylic acid, myrcene, geraniol, citral, H 2 O and some low molecular mass fragments. In turn, the oxidative decomposition of the tested copolymers run in two main stages. The first stage from 205 °C± 5–230 °C± 4–340–380 °C was visible. This was connected with the emission of benzyl methacrylate, myrcene, citral, low molecular mass alkenes and ketones, CO 2 , H 2 O and CO. The second stage occurred from 340° to 380–520 °C. Mainly, the formation of CO 2 , H 2 O and CO and some low molecular mass fragments was observed. The type of the formed volatiles indicated that the pyrolysis and oxidative decomposition were initiated by a radical mechanism. The symmetric cleavage of the C-C and C-O bonds in the main and side macromolecular chains of the studied GM- co -BM materials (inert conditions) and additional chemical reactions of the formed fragments with oxygen and/or residues (oxidative conditions) were confirmed. [Display omitted] • Pyrolysis and oxidative decomposition paths of novel copolymers by the TG/FTIR/QMS were studied. • Pyrolysis gases were methacrylate ester and acid, alcohol, aldehyde, alkene and H 2 O. • Oxidative decomposition gases were methacrylate ester, alkenes, ketones, aldehydes, CO 2 , H 2 O and CO. • Pyrolysis and oxidative decomposition proceeded according to radical mechanism. [ABSTRACT FROM AUTHOR]

Until now, a number of new polymers have been discovered with the aid of experimental and computational molecular approaches and indicated to have potential applications. All the computational molecular approaches provide information helpful to further study. So, monomer and homopolymer of benzyl methacrylate (BzMA), which is a popular methacrylate ester monomer, were synthesized and investigated based on density functional theory (DFT) and Hartree-Fock (HF) methods. The monomer and homopolymer were characterized by FTIR, 1H, and 13C NMR techniques. The molecular geometry, geometrical parameters, Mulliken atomic charges, and vibrational frequencies of BzMA monomer and homopolymer (in dimer form) were calculated by using the DFT and HF methods with 6-31G (d, p) as basis set. The molecular electrostatic potential maps and molecular orbitals properties of monomer and homopolymer were calculated using the 6-31G (d, p) basis set of theories. Besides, 1H and 13C chemical shifts were calculated by the gauge -including atomic orbital approach. The results demonstrated that the theoretical values were in good agreement with the experimental values. The calculated data are important to providing insight into molecular analysis and may be used in technological applications. [ABSTRACT FROM AUTHOR]

A series of dodecyl-based monofunctional trithiocarbonate chain transfer agents (CTAs) were successfully synthesized, toward the reversible addition-fragmentations chain transfer (RAFT) polymerization of styrene. The CTAs were used as initiators for RAFT polymerization, in the absence of the conventional free radical initiator, at higher temperature. Polystyrene (PS) of narrow polydispersity index (PDI) is synthesized. Subsequently, poly(styrene- b-benzyl methacrylate) diblock and poly(styrene- b-benzyl methacrylate- b-2-vinyl pyridine) triblock copolymers were synthesized from the PS macro-RAFT agent by simply heating with the second and third monomer, respectively. These experiments suggest that it should be possible to control the RAFT polymerization initiated by a CTA through the adjustment of the temperature of polymerization in such manner that initiation is tailored to proceed at faster rate (at higher temperature) in comparison to propagation (lower temperature). For the specific CTAs studied in this work, the polymerization rate of styrene was high in the case of the reinitiating cyano (CN)-substituted group (R group) compared to the other groups studied. The results further show that 4-cyano pentanoic acid group is superior to the other R groups used for the RAFT polymerization of styrene, especially based on the polydispersity at a given conversion as well as the variation in the expected and experimental number-average-molecular weights. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 [ABSTRACT FROM AUTHOR]

[Display omitted] • Provides evaluation of excess properties of PEG 200 + benzyl methacrylate mixtures. • Reports new density and refractive index data of PEG 200 + benzyl methacrylate mixtures. • Reports new speed of sound data of PEG 200 + benzyl methacrylate mixtures. • Provides information on the nature of interactions in these mixtures. • Scaled particle theory has been applied to predict speed of sound theoretically. Green and biodegradable solvents are requisite replacements to volatile organic solvents. Polyethylene glycols have been recognized as alternatives to volatile organic solvents in numerous industrial and pharmaceutical applications because of their unique properties. In this work the measurements of physicochemical properties, viz., densities, ρ , speeds of sound, u and refractive indices, n D of the binary mixtures of PEG 200 with benzyl methacrylate, including pure liquids, over the entire mole fraction range at the temperatures, T /K = 293.15 to 318.15 and at atmospheric pressure, p = 101 kPa. The experimental data were used to calculate the excess molar volume, V m E , excess isentropic compressibility, κ s E , excess speed of sound, u E , excess acoustic impedance, Z E , excess molar isentropic compressibility, K s,m E , excess refractive index, n D E and deviation in molar refraction, Δ R M . These excess properties were fitted with the Redlich-Kister polynomial equation. In addition, the partial molar volumes and partial molar compressibilities and excess partial molar volumes and excess partial molar compressibilities over the entire mole fraction range; and at infinite dilution were also calculated. The trends of these parameters with composition and temperature were discoursed from the point of view of intermolecular interactions existed in these mixtures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Provides estimation of excess properties of PEG 400 + benzyl methacrylate mixtures. • Reports new density and refractive index data of PEG 400 + benzyl methacrylate mixtures. • Reports new speed of sound data of PEG 400 + benzyl methacrylate mixtures. • Provides information on the nature of interactions in these mixtures. • Applicability of refractive index mixing rules to these mixtures is checked. In the present study, the physicochemical properties such as the excess molar volumes, excess isentropic compressibilities, excess speeds of sound, excess molar compressibilities, excess refractive indices, and partial and excess partial molar volumes/compressibilities have been evaluated from the experimentally measured data of density, speed of sound and refractive index for the binary mixtures of polyethylene glycol 400 (PEG 400) with benzyl methacrylate over entire mole fraction range at the temperatures, T /K = (293.15–318.15) and pressure, p = 101 kPa. The partial molar volume/compressibility and excess partial molar volume/compressibility at infinite dilution have also been calculated. The correlations of the excess properties were made with the Redlich-Kister polynomial equation. The observed excess functions have been used to discuss the intermolecular interactions prevailing between the components in this system. Also, some theoretical mixing rules for correlating the refractive indexes were assessed and the results were compared with experimental data. [ABSTRACT FROM AUTHOR]

The cyclic methacrylate monomer benzyl methacrylate (BzMA) was evaluated as an alternative to traditional methyl methacrylate (MMA) as a hard monomer in the application of an acrylate latex pressure sensitive adhesive (PSA). The influences of BzMA on the resultant latex and PSA properties were comprehensively investigated. Both FTIR and 1H NMR analysis indicated that BzMA could be successfully introduced into the latex PSA copolymer through emulsion polymerization. TEM images illustrated that the synthesized latex particles are spherical and uniform. DSC and TGA results showed that the T g of the copolymer was elevated, while thermal stability was first increased and then decreased with the introduction of BzMA. Besides, it was also found that the water resistance of the latex PSA was improved by the presence of BzMA, which was confirmed by water contact angle measurements. Furthermore, as the BzMA content increased, the gel content slightly decreased, while sol molecular weight (M w , M n) of the polymer increased. Finally, with respect to the adhesive properties of the PSA, it was observed that loop tack decreased, while shear strength increased with the incorporation of BzMA. 180° peel strength initially increased and then decreased with the addition of BzMA from 0 to 30 wt%, with a maximum value at 5 wt%. [ABSTRACT FROM AUTHOR]

• We have synthesized copolymer containing (DEAMSt) monomer with (BMA) monomer units and then synthesized its Ni(II), Co(II) and Zn (II) metal complexes. • Spectroscopic characterizations of these structures were determined in experimental and theoretically. • All results were found to be compatible with each other. A copolymer containing 4-Diethanolaminomethyl Styrene (DEAMSt) monomer with Benzyl Methacrylate (BMA) monomer units were synthesized by free radical solution polymerization technique using AIBN as a free radical initiator and 1,4-dioxane as a solvent at 60 °C. The metal complexes were prepared by reaction of the copolymer used as ligand poly(DEAMSt0.70-co BMA) and Ni(II), Co(II) and Zn(II) metal ions in presence of ethanol and dilute NaOH at 65 °C for 48 h in pH 6. The structure of copolymer used as ligand and polymer-metal complexes were characterized by (FT-IR), 1H NMR, elemental analysis, and SEM-EDX techniques. For the theoretical calculations (FT-IR and 1H NMR spectrum) the Hartree-Fock (HF) theory with 6-31G (6D, 7F) basic set was used. In addition, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energies were investigated. A good agreement has been found between the theoretical and experimental FT-IR and 1H NMR results. [ABSTRACT FROM AUTHOR]