Determination Of Monomer Reactivity Ratios Research Articles

Synthesis and characterization of (allylamine hydrochloride-vinyl sulfonic acid) copolymer and determination of monomer reactivity ratios

Synthesis and characterization of (allylamine hydrochloride-vinyl sulfonic acid) copolymer and determination of monomer reactivity ratios

Novel Methacrylamide Polymers Based on Thiazole and Styrene: A Study on Synthesis, Characterization, and Determination of Monomer Reactivity Ratios

In this study, firstly, a thiazole methacrylamide (TMAAm) monomer was synthesized from methacryloyl chloride with 2-aminothiazole. Later on, a series of copolymers of 2-thiazole methacrylamide (TMAAm) with styrene (St) using strange compositions in the feed has been prepared in solution via radical at 70 oC with AIBN as initiator. The structure of the copolymers was elucidated by FT-IR, 1H-NMR, and 13C-NMR spectroscopy methods. The compositions of the copolymers were determined from the nitrogen (N) difference according to the elemental analysis results. Monomer reactivity ratios; The rTMAAm and rSt, Fineman-Ross (FR), Kelen-Tüdös (KT) linear methods, and the error method model in non-linear variables were calculated with the computer program RREVM. The molecular weights and heterogeneity indices of the copolymers were determined by the GPC method. The thermal stability of the copolymers was investigated by thermogravimetry (TG) measurements.

Determination of monomer reactivity ratios from a single sample using multivariate analysis of the 1H NMR spectra of poly[(methyl methacrylate)-co-(benzyl methacrylate)

Determination of monomer reactivity ratios from a single sample using multivariate analysis of the 1H NMR spectra of poly[(methyl methacrylate)-co-(benzyl methacrylate)

Microstructural Characteristics Analysis of PCE Copolymer from Methyl Allyl Polyethylene Glycol and Methacrylic Acid based on Determination of Monomer Reactivity Ratios

Microstructural Characteristics Analysis of PCE Copolymer from Methyl Allyl Polyethylene Glycol and Methacrylic Acid based on Determination of Monomer Reactivity Ratios

In Situ Synthesis of Poly(butyl methacrylate) in Anodic Aluminum Oxide Nanoreactors by Radical Polymerization: A Comparative Kinetics Analysis by Differential Scanning Calorimetry and 1H-NMR.

In this work, we explore the ability to generate well-defined poly(butyl methacrylate) (PBMA) nanostructures by “in situ” polymerization of butyl methacrylate monomer (BMA). PBMA nanostructures of high and low aspect ratios have been successfully obtained through the free radical polymerization (FRP) of a BMA monomer in anodic aluminum oxide (AAO) nanoreactors of suitable size. A polymerization kinetics process has been followed by differential scanning calorimetry (DSC) and proton Nuclear Magnetic Resonance spectroscopy (1H-NMR).The determination of the kinetics of polymerization through DSC is based on a quick and direct analysis of the exothermic polymerization process, whereas the analysis through 1H-NMR also allows the unambiguous chemical analysis of the resulting polymer. When compared to bulk polymerization, both techniques demonstrate confinement effects. Moreover, DSC and 1H-NMR analysis give the same kinetics results and show a gel-effect in all the cases. The number average molecular weight (Mn) of the PBMA obtained in AAO of 60–300 nm are between 30·103–175·103 g/mol. Even if the Mn value is lower with respect to that obtained in bulk polymerization, it is high enough to maintain the polymer properties. As determined by SEM morphological characterization, once extracted from the AAO nanoreactor, the polymer nanostructures show controlled homogeneous aspect/size all throughout the length of nanopillar over a surface area of few cm2. The Young’s modulus of low aspect ratio PBMA nanopillars determined by AFM gives a value of 3.1 ± 1.1 MPa. In this work, a 100% of PBMA polymer nanostructures are obtained from a BMA monomer in AAO templates through a quick double process: 30 min of monomer immersion at room temperature and 90 min of polymerization reaction at 60 °C. While the same nanostructures are obtained by polymer infiltration of PBMA at 200 °C in about 6 h, polymerization conditions are much softer than those corresponding to the polymer infiltration process. Furthermore, the 1H-NMR technique has been consolidated as a tool for studying the kinetics of the copolymerization reactions in confinement and the determination of monomer reactivity ratios.

Determination of Monomer Reactivity Ratios in Controlled Copolymerization of Acrylonitrile with Unsaturated Methyl Esters

This paper reports the investigation of copolymerization of acrylonitrile with methyl acrylate, dimethyl maleate, dimethyl fumarate and dimethyl itaconate via atom transfer radical polymerization mechanism using copper bromide as a catalyst in combination with tris(2-pyridylmethyl)amine as a ligand. The reactivity ratios of monomers were evaluated using the Finemann–Ross and Kelen–Tudos methods basing on the copolymer composition determined by 1H NMR spectroscopy. It was found that reversible deactivation mechanism has no significant influence on the monomer reactivity ratios. It was found that among the tested comonomers methyl acrylate and dimethyl itaconate seem to be the most suitable ones for obtaining well-defined copolymers of acrylonitrile.

Determination of monomer reactivity ratios and thermal properties of poly(GMA-co-MMA) copolymers

In this study, the free radical copolymerization of glycidyl methacrylate (GMA) and methyl methacrylate (MMA) was investigated for the first time by solution free radical copolymerization in toluene at 80 °C using azobisisobutyronitrile as an initiator. The 1H-NMR spectroscopy has been used for determining the copolymer composition. Monomer reactivity ratios (r values) were calculated by various linear least-square methods. According to the results, using the Kelen–Tudos (KT) and extended Kelen–Tudos (Ex KT) methods the r values were obtained as $$ r_{\text{G}} = 1.528 \pm 0.168 $$ , $$ r_{\text{M}} = 0.789 \pm 0.121 $$ , and $$ r_{\text{G}} = 1.577 \pm 0.186 $$ , $$ r_{\text{M}} = 0.783 \pm 0.129 $$ , respectively. The calculated monomer reactivity ratios showed the higher reactivity for GMA (rG) compared to MMA (rM). Furthermore, the findings demonstrated random or ideal behavior ( $$ r_{\text{G}} \cdot r_{\text{M}} \simeq 1 $$ ) for these copolymers. The monomers sequence distribution as probability of finding the multiple sequence distribution of the GMA and MMA units in copolymers was calculated and showed higher probabilities for GMA sequences. Thermogravimetric analysis of the copolymers had three degradation stages, and the main degradation occurred at third stage (340–456 °C) with 56% weight loss. Also, with regard to initial temperature of degradation and T50, the thermal stability was improved 62% and 2.3%, respectively, by increasing MMA content in copolymer. These studies could uncover the underlying GMA–MMA composition in copolymer, shedding light on the future design of top-performing applications such as UV printing ink and resin industry.

Homopolymerization and synthesis of a new methacrylate monomer bearing a boron side group: characterization and determination of monomer reactivity ratios with styrene

Boron methacrylate (BAc) monomer was synthesized via an esterification reaction. Boric acid, neopentyl glycol, and 2-hydroxyethyl methacrylate (HEMA) were reacted to obtain boron-containing acrylic monomer. Characterization was achieved by FT-IR, $^{13}$C NMR, $^{1}$H NMR, and $^{11}$B NMR and the results for the synthesized monomer were compared to those for HEMA. Homopolymer and copolymers with styrene (St) were synthesized via free radical polymerization. The properties of the synthesized styrene copolymers were investigated using several techniques. Monomer reactivity ratios for the studied monomer pair were calculated using the extended Kelen-Tudos method. Copolymerization compositions and reactive ratios showed that the obtained copolymers had random characters. Thermal behaviors of the synthesized polymers were studied by thermal gravimetric analysis and differential scanning calorimetry methods. Boron methacrylate homopolymer showed one glass transition temperature at 73.7 $^{\circ}$C. Depending on copolymer composition, the glass transition temperatures of boron methacrylate-styrene copolymers were between 68.4 $^{\circ}$C and 81.5 $^{\circ}$C.

Synthesis and characterization of trans-1,4-butadiene/isoprene copolymers: Determination of monomer reactivity ratios and temperature dependence

A series of trans-1,4-butadiene/isoprene copolymers were prepared using the catalyst system TiCl4/MgCl2-Al(i-Bu)3 with bulk precipitation technology at different temperatures. Monomers reactivity ratios were calculated based on the Kelen-Tudos (K-T) method and the Mao-Huglin (M-H) method. The influence of temperature on copolymer composition and polymerization rate was discussed in detail. The increase of reaction temperature brought the decrease of butadiene reactivity ratio rBd and supplied an effective adjustment on copolymers’ composition distribution.

Homo- and copolymerization of N-(2-thiazolyl)methacrylamide with different vinyl monomers: Synthesis, characterization, determination of monomer reactivity ratios and biological activity

N-(2-thiazolyl)methacrylamide (TMA) monomer was synthesized from 2-aminothiazole by two different methods. The homo- and copolymerization of this monomer with methyl methacrylate (MMA), styrene (St), acrylonitrile (AN), and vinyl acetate (VA) were performed in dimethyl formamide using 1 mol% AIBN at 70°C. The copolymerization behavior was studied in a wide composition interval with the mole fractions of TMA ranging from 0.1 to 0.7 in the feed. Characterization using FTIR and 1HNMR techniques confirmed the structure of the monomer and the prepared homo- and copolymers, but the copolymers compositions were determined from sulphur analysis. The monomer reactivity ratios were computed using Fineman and Ross and Kelen and Tudos methods for the systems TMA-MMA, TMA-St, TMA-AN and TMA-VA and were found to be r 1 = 0.59 ± 0.05, r 2 = 2.72 ± 0.03; r 1 = 0.39 ± 0.02, r 2 = 0.90 ± 0.01; r 1 = 0.77 ± 0.06, r 2 = 1.99 ± 0.04 and r 1 = 0.80 ± 0.08, r 2 = 0.40 ± 0.05 respectively (r 1 corresponds to monomer reactivity ratio of TMA). The Q and e values for TMA monomer were found to be 1.079 and −0.054. The synthesized monomer and polymers were tested in vitro for biological activity against some microorganisms, using the disk diffusion technique. Generally, all the polymers were effective against the tested microorganisms, but their growth-inhibition effects varied.

New terpolymers from n-butyl acrylate, glycidyl methacrylate and tetrahydrofurfuryl acrylate: Synthesis, characterisation and estimation of reactivity ratios

Development and practical application of multicomponent copolymerisation systems, such as terpolymerisation, is an on-going process because even a small addition of a particular comonomer may have a significant impact on the desired property. Commonly, three separate pairs of binary polymerisation experiments are carried out to obtain monomer reactivity ratios (MRR) values that relates to the ternary polymerisation reactions. However, the reaction conditions in each binary system may not be representative of the whole ternary system. The error-in-variables model (EVM) method is a relatively recent statistical approach to solving multi-response parameter estimation problems, with the advantage that all MRR parameters can be directly estimated from terpolymerisation data. New ternary copolymers derived from n-butyl acrylate (nBA), glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesised in solution at 70±1 °C in the presence of benzoyl peroxide (BPO) as a free radical initiator. The terpolymers were characterised by 1H NMR, 13C NMR and FTIR spectroscopic techniques. The terpolymer compositions were determined using 1H NMR analysis. The polydispersities of the terpolymers with values between 1.66 and 1.85 suggest a strong tendency for chain termination by disproportionation. The glass transition temperatures of the terpolymers are found to be between those of the corresponding homopolymers and relative to their content. Increase in the nBA or THFA contents and decrease in the GMA content in terpolymers results in a decrease in the glass transition temperatures. The determination of MRR for the ternary system was obtained by employing the EVM model. Experimental terpolymerisation data agree well with calculations based on the Alfrey-Goldfinger equation and the unitary and binary azeotropes were calculated.

Stereoregularity evolution of isobornyl acrylate and styrene copolymers by 2D NMR spectroscopy

Isobornyl acrylate/styrene (B/S) copolymers of different compositions have been prepared by Atom Transfer Radical Polymerization (ATRP) using methyl-2-bromopropionate as an initiator and PMDETA/CuBr as catalyst under nitrogen atmosphere at 60°C. Copolymer compositions calculated from 1H NMR spectra are used to determine the reactivity ratios of monomers. Linear Kelen–Tudos (KT) and non-linear error in variable methods (EVM) have been employed for determination of monomer reactivity ratios in copolymers. The reactivity ratios obtained from KT and EVM are found to be rB=0.41±0.08, rS=0.92±0.13 and rB=0.41 and rS=0.93 respectively. These copolymers have been analyzed for their stereochemical structure using various 1D (1H, 13C{1H}, DEPT) and 2D (HSQC, TOCSY, NOESY, HMBC) NMR techniques. 2D HSQC and TOCSY NMR experiments are employed to resolve the highly overlapped and complex 1H and 13C{1H} NMR spectra of the copolymers. Spatial coupling of different types of protons are resolved by 2D NOESY NMR spectra. The configurational and compositional sequences of β-methylene carbons are assigned upto tetrad level whereas methine carbon is assigned as triad level of compositional sequences. The quaternary carbon of styrene and carbonyl carbon of isobornyl acrylate have been assigned as triad level of compositional sequences and are further confirmed by 2D HMBC NMR spectra.

Well-defined graft copolymers of tert-butyldimethylsilyl methacrylate and poly(dimethylsiloxane) macromonomers synthesized by RAFT polymerization

Graft copolymers of hydrolyzable tert-butyldimethylsilyl methacrylate (TBDMSiMA) and low surface energy poly(dimethylsiloxane) methacrylate of 1000 g mol−1 (PDMSMA1k) and 5000 g mol−1 (PDMSMA5k) were synthesized by the RAFT process, using 2-cyanoprop-2-yl-dithiobenzoate (CPDB) as a chain transfer agent, at 70 °C, in xylene. The homopolymerizations of each monomer were first studied, demonstrating their control by the RAFT process. Simultaneous copolymerizations of TBDMSiMA and PDMSMA led to gradient graft copolymers as demonstrated by the determination of monomer reactivity ratios by the Jaacks method. Sequential polymerizations led to diblock or blocky graft copolymers depending on the order of addition of each monomer. All the copolymerizations were controlled by the RAFT process with molecular weight values close to the theoretical values, together with monomodal and narrow distributions (PDI < 1.2). The graft copolymers exhibited two glass transition temperatures, corresponding to the PDMS- and pTBDMSiMA-enriched phases, respectively. The PDMS side chain distribution and length were shown to be significant parameters influencing the thermal behavior of the copolymers, their low surface energy and their erosion properties in artificial seawater. These latter properties make these graft copolymers suitable for applications as binders for self-polishing/fouling release hybrid antifouling coatings.

Synthesis and characterization of poly[(1-vinyl-1,2,4-triazole)-co -(monomer with carboxylic acid group(s))] and determination of monomer reactivity ratios: I. Acrylic acid

Copolymers of 1-vinyl-1,2,4-triazole (VTAz) and acrylic acid (AA) having different mole ratios were synthesized using free radical-initiated solution polymerization in dimethylformamide at 70 °C with α,α′-azobisisobutyronitrile as initiator in nitrogen atmosphere. The compositions of the synthesized copolymers for a wide range of monomer feeds were determined using Fourier transform infrared (FTIR) spectroscopy through recorded absorption bands for VTAz (1510 cm−1, CN (triazole ring) stretching mode) and AA (1710 cm−1, CO stretching mode) units. The structures of the copolymers were characterized using FTIR and 1H NMR spectroscopy. The copolymer compositions were also determined from 1H NMR analysis following proton signals of carboxyl group at 11.8–12.5 ppm of AA and of triazole ring at 7.5–8.1 ppm of VTAz. Monomer reactivity ratios for the VTAz-AA pair were estimated using linear methods, i.e. Fineman–Ross (FR) and Kelen–Tüdös (KT). From FTIR evaluation, monomer reactivity ratios were calculated as r1 = 0.404 and r2 = 1.496 using the FR method and r1 = 0.418 and r2 = 1.559 using the KT method. These values were found to be very close to those obtained from NMR evaluation. The two cases r1r2 < 1 and r1 < r2 indicated the random distribution of the monomers in the final copolymers and the presence of a greater amount of AA units in the copolymer than in the feed, respectively. The observed relatively high activity of complexed growing radical-AA• … VTAz was explained by the effect of complex formation between carbonyl groups and triazole fragments in chain growth reactions. Thermal behaviours of copolymers with various compositions were investigated using thermogravimetric and differential scanning calorimetric analyses. It was observed that thermal stabilities and glass transition temperatures of the copolymers increased resulting from complex formation between acid and triazole units. © 2012 Society of Chemical Industry

Synthesis of fluorescent poly(1‐vinylimidazole‐co‐(1‐pyrene) methyl 2‐methyl‐2‐propenote) and determination of monomer reactivity ratios

AbstractA new fluorescent copolymer, poly(1‐vinylimidazole‐co‐(1‐pyrene) methyl 2‐methyl‐2‐propenote) (VI‐co‐PyMMP), has been designed and synthesized by a free‐radical copolymerization of VI and PyMMP as well as characterized using ultraviolet (UV), Fourier transform infrared spectroscopy (FTIR), 1H NMR, and fluorescence spectroscopies. The monomer reactivity ratios are determined by two methods of Fineman‐Ross (r1 = 0.28 ± 0.04 for VI, r2 = 1.32 ± 0.11 for PyMMP) and Kelen‐Tüdös (r1 = 0.23 ± 0.05, r2 = 1.22 ± 0.12). Based on the reactivity ratios, the monomer sequence lengths and Q and e for PyMMP monomer are further calculated. The results suggest that the copolymerization of VI and PyMMP is a nonideal copolymerization without an azeotropic point (i.e., r1 &lt; 1, r2 &gt; 1 and r1r2 &lt; 1) and has a low alternation tendency. The conclusions drawn in this work may not only direct the later synthesis of the copolymers but also enrich the database of free‐radical copolymerization. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Synthesis, characterization of poly (4-benzyloxyphenylmethacrylate) and its copolymer with butyl methacrylate and determination of monomer reactivity ratios

The monomer 4-benzyloxyphenylmethacrylate (4-BOPMA) was synthesized by reacting 4-benzyloxy phenol dissolved in methylethylketone (MEK) with methacryloyl chloride in the presence of triethylamine. The homopolymer and various copolymers of 4-BOPMA with butylmethacrylate (BMA) were synthesized by the free radical polymerization in MEK at 70 ± 1 °C in nitrogen atmosphere using benzoylperoxide as initiator. The homopolymer and copolymers were characterized by various spectral techniques like IR, 1H-NMR, 13C-NMR spectroscopic techniques. The molecular weights of the polymers were determined by gel permeation chromatography. The glass transition temperatures of polymers were determined by differential scanning calorimeter. The thermal stability of the polymers was performed by thermo gravimetric analysis in inert atmosphere. The monomer reactivity ratios were determined using the conventional linearization methods such as Fineman–Ross (r1 = 0.438, r2 = 0.2323), Kelen Tudos (r1 = 0.4648, r2 = 0.2992) and extended Kelen Tudos (r1 = 0.4489, r2 = 0.2616).

Synthesis, characterization and thermal properties of homo and copolymers of 3,5-dimethoxyphenyl methacrylate with glycidyl methacrylate: Determination of monomer reactivity ratios

The new methacrylic monomer, 3,5-dimethoxyphenyl methacrylate (DMOPM) was synthesized by reacting 3,5-dimethoxyphenol dissolved in ethyl methyl ketone (EMK) with methacryloyl chloride in presence of triethylamine as a catalyst. The homopolymer and copolymers of DMOPM with glycidyl methacrylate (GMA) were synthesized by free radical polymerization in EMK solution at 70 ± 1 °C using benzoyl peroxide as a free radical initiator. The copolymerization behaviour was studied in a wide composition interval with the mole fractions of DMOPM ranging from 0.15 to 0.9 in the feed. The homopolymer and the copolymers were characterized by FT-IR, 1H NMR and 13C NMR spectroscopic techniques. The solubility was tested in various polar and non-polar solvents. The molecular weight and polydispersity indices of the polymers were determined using gel permeation chromatography. The glass transition temperature of the copolymers increases with increase in DMOPM content. The thermogravimetric analysis of the polymers showed that the thermal stability of the copolymer increases with DMOPM content. The copolymer composition was determined using 1H NMR spectra. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman–Ross ( r 1 = 0.520, r 2 = 2.521), Kelen–Tudos ( r 1 = 0.629, r 2 = 2.554) and extended Kelen–Tudos methods ( r 1 = 0.600, r 2 = 2.502).

Novel Copolymers of 4-Chloronaphthyl Methacrylate with Acrylonitrile: Determination of Monomer Reactivity Ratios and Antimicrobial Activity

Methacrylate based monomer, 4-chloronaphthyl methacrylate (4-CNMA) was synthesized by reacting 4-chloro naphthol with methacryloyl chloride in the presence of triethylamine (NR3) at 0–5°C. The free-radical initiated copolymerization of (4-CNMA), with acrylonitrile (AN) was carried out in 1,4-dioxane-dimethyl sulfoxide mixture (8:2) solution at 70 ± 1°C using 2,2′-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios in the feed. The monomer 4-CNMA, poly(4-CNMA) and copolymers were characterized by FT-IR and 1H-and 13C-NMR spectral studies. The copolymer composition obtained by elemental analysis led to the determination of reactivity ratios employing Fineman-Ross (F-R), Kelen-Tüdös (KT) and Extended Kelen-Tüdös (EKT) linearization methods. These parameters were also estimated using a non-linear computational fitting procedure, known as reactivity ratios error in variable model (RREVM). The solubility of the polymers was tested in various polar and non-polar solvents. Gel permeation chromatography was employed to determine the molecular weights (Mw and Mn) and polydispersity index of polymers. Thermogravimetric analysis of the polymers reveals that the thermal stability of the copolymers increases with increase in the mole fraction of 4-CNMA in the copolymers. The prepared homo and copolymers were tested for their antimicrobial activity against bacteria, fungi and yeast.

Copolymers of N-vinylcarbazole with Acrylic Acid, Itaconic Acid, and N-isopropylacrylamide: Synthesis, Determination of Monomer Reactivity Ratios, and Electrochemical Properties

Free radical copolymerizations of N-vinylcarbazole (NVCz) with acrylic acid (AA), itaconic acid (IA), and N-isopropylacrylamide (NIPAAm) at different feed ratios were conducted in 1,4-dioxane at 50°C. The copolymers were characterized by UV and FT-IR spectroscopic techniques, viscosity, and glass transition temperature measurements. The monomer reactivity ratios were determined by application of the extended Kelen-Tüdós method, which is one of the conventional linearization methods, and found to be rNVCz = 0.29 and rNIPAAm = 0.12, rNVCz = 0.84 and rIA = 0.12, rNVCz = 0.86 and rAA = 0.31 by UV, and rNVCz = 0.32 and rNIPAAm = 0.07 by FT-IR. Polymer-modified electrodes having electroactive, ionic, and hydrophobic properties were prepared by electro-oxidation using PNVCz, NVCz/NIPAAm, and NVCz/IA copolymers and tested as sensor electrodes to dopamine.

Reactivity ratios and monomer partitioning in the microemulsion copolymerization of vinyl acetate and butyl acrylate

AbstractThe true monomer reactivity ratios for the vinyl acetate/butyl acrylate system were determined with experimental data from the cumulative copolymer composition at low, intermediate, and high conversions and with the monomer partitioning among the aqueous, microemulsion droplet, and polymer particle phases taken into account. A mixture of sodium dodecyl sulfate and poly(ethylene oxide) (23) dodecyl ether (Brij‐35; 3 : 1 w/w) was used as a stabilizer. Potassium persulfate was used as an initiator. The true values of the monomer reactivity ratios were 0.028 ± 3.2 × 10−3 for vinyl acetate and 6.219 ± 3.1 × 10−1 for butyl acrylate, and these were in agreement with those reported in the literature for bulk copolymerizations but differed from values reported for other compartmentalized copolymerizations. Thus, these results indicate that the monomer partitioning and cumulative copolymer composition throughout the reaction have to be duly accounted for in the determination of monomer reactivity ratios in heterogeneous polymerizations. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009