Coordination copolymerization of butadiene and isoprene with rare earth chloride–alcohol–aluminum trialkyl catalytic systems

Butadiene and isoprene were copolymerized with LnCl₃–ROH–AIR₃ catalytic system. The products obtained were confirmed to be copolymers by their glass transition temperatures and characteristic pyrolytic chromatograms, etc. The equation for copolymerization rate may be expressed as R_p = K_p(M)²(cat). The rate constants of copolymerization, activation energy, and monomer reactivity ratios for catalytic systems containing various rare earth elements in III-B family and different solvents were determined. It was found that the reactivity ratio of butadiene was greater than that of isoprene and r₁r₂ near 1, and the composition and microstructure of copolymers were not much affected by variation of polymerization conditions. Both monomer repeat units in the copolymers had cis-1,4 contents above 95%, which is a distinguishing feature of coordination polymerization with the lanthanide catalyst system.     

Synthesis of novel functionalized methacrylate copolymers and their copolymerization kinetics,thermal stability,and biocidal properties

In the first step of this study, 2-[(methoxy-1,3-benzothiazole-2-yl)amino]-2-oxoethyl methacrylate (MBAOM) monomer was synthesized and characterized. Then, a series copolymers were obtained by free-radical copolymerization method of MBAOM and glycidyl methacrylate, which is a commercial monomer at 65°C in 1,4-dioxane solvent. Structural characterizations of synthesized monomer and copolymers were carried out using Fourier transform infrared spectrophotometer and nuclear magnetic resonance spectroscopy (¹H and ¹³C-NMR) instruments. The composition of the copolymers was estimated by elemental analysis. The thermal behaviors of all the polymers have been investigated using the differential scanning calorimetry and the thermogravimetric analysis. A kinetic study of the thermal decomposition of copolymers was investigated using thermogravimetric analyzer with non-isothermal methods selected for analyzing solid-state kinetics data. The activation energy (E_a) values were calculated via Kissinger and Ozawa models in a period of α = 0.10–0.80. Photostability of the copolymers was investigated. Also, the biological activity of the copolymers against different bacterial and fungal species has been investigated.     

Compositional and configurational sequence determination of methacrylonitrile–vinylidene chloride copolymers by nuclear magnetic resonance spectroscopy

Methacrylonitrile–vinylidene chloride (M/V) copolymers of different composition were prepared by bulk polymerization using benzoyl peroxide as an initiator under nitrogen atmosphere in a sealed tube. The copolymer composition was determined from quantitative ¹³C[¹H] NMR spectra. The reactivity ratios for M/V copolymers obtained from a linear Kelen–Tudos method and nonlinear error‐in‐variables method are r_M = 2.47 ± 0.14, r_V = 0.40 ± 0.02, and r_M = 2.43, r_V = 0.39, respectively. The complete spectral assignment in term of compositional and conformational sequences of these copolymers were done with the help of distortionless enhancement by polarization transfer, two‐dimensional heteronuclear single‐quantum coherence spectroscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1865–1874, 2005     

NMR studies of poly(2-hydroxy ethyl methacrylate-co-2-vinyl pyridine)

Copolymers of 2-hydroxy ethyl methacrylate-2-vinyl pyridine (H/V) of different composition were synthesized by free radical bulk polymerization using azobisisobutyronitrile (AIBN) as an initiator under nitrogen atmosphere. The copolymer compositions were calculated from ¹H NMR spectra. The reactivity ratios for H/V copolymers obtained from a linear Kelen-Tudos method (KT) and nonlinear error-in-variables method (EVM) are r_H = 0.50 ± 0.10, r_V = 1.04 ± 0.08 and r_H = 0.55, r_V = 1.06 respectively. The complete spectral assignment of methine, methylene, methyl, carbonyl, and aromatic carbon regions in term of compositional and configurational sequences of H/V copolymers were done with the help of ¹³C{¹H} NMR, distortionless enhancement by polarization transfer (DEPT), two-dimensional heteronuclear single quantum coherence (HSQC) along with total correlated spectroscopy (TOCSY). © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Copolymerization of methyl methacrylate with 4‐vinylpyridine initiated by a novel Ni(II)α‐Benzoinoxime complex

Copolymerizations of methyl methacrylate (MMA) with 4‐vinylpyridine (4VP) were performed from different monomer feed ratios in 1,4‐dioxan at 30°C under free radical initiation experimental conditions, using Ni(II)α‐Benzoinoxime complex as initiator. The obtained copolymers (PMMA4VP) were examined by FTIR and ¹H NMR spectroscopies. The composition of these copolymers was calculated, using ¹H NMR spectra and elemental analysis. Monomer reactivity ratios were estimated from Fineman–Ross (FR, r_m = 0.550, r_v = 1.165) and Kelen–Tudos (KT, r_m = 0.559, r_v = 1.286) linearization methods, as well as nonlinear error in variables model (EVM) method using the RREVM computer program (RREVM, r_m = 0.559, r_v = 1.264). These values suggest that MMA‐4VP pair copolymerizes randomly. ¹H NMR spectra provide information about the stereochemistry of the copolymers in terms of sequence distributions and configurations. These results showed that the age of the Ni complex has an impact not only on its activity towards polymerization reactions but also on the features of the corresponding copolymers, whereas the chemical composition was insensitive to this prominent factor. The mechanism of MMA‐4VP copolymerization is consistent with a radical process as supported by microstructure and molecular weight distribution studies. Thermal behaviours of these copolymers were investigated by differential scanning calorimetry and thermogravimetric analysis. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Charge transfer copolymerization and properties of isopropyl methacrylate with acrylonitrile and methacrylonitrile

Isopropyl methacrylate (IPMA) with Acrylonitrile (AN) and Methacrylonitrile (MAN) copolymers of different copositions were prepared at 60°C and 80°C, respectively, using a mixture of n-Butylamine (nBA) and carbon tetrachloride (CCl₄) in dimethyl sulphoxide (DMSO) as a charge transfer (CT) initiator. The percentage composition of the copolymers was established by elemental analysis. The copolymerization reactivity ratios were computed by the Kelen–Tudos method. In both the systems, IPMA was found to be more reactive; the copolymers sequence was random in nature. The copolymers were characterized by IR, ¹H-NMR, ¹³C-NMR spectroscopy and intrinsic viscosity measurements in dimethyl formamide (DMF) at 30±0.1°C. The thermal behavior of the AN-IPMA copolymers was studied by thermogravimetry (TG) in air. The thermal stability increased, with increasing AN content in the copolymer chain. The solubility parameter of AN-IPMA copolymer was evaluated by studying the intrinsic viscosity in different solvents. The solubility parameter of the copolymer was found to be 9.7 (cal/cc)^1/2.     

Investigation of microstructure of 4‐vinyl pyridine–methacylonitrile copolymers by NMR spectroscopy

4‐Vinyl pyridine–methacrylonitrile (V/M) copolymers of different composition were prepared by bulk polymerization using benzoyl peroxide as an initiator. The copolymer composition was determined from quantitative ¹³C{¹H}‐NMR spectra. The reactivity ratios for V/M copolymer obtained from a linear Kelen‐Tudos method (KT) and nonlinear error‐in‐variables method (EVM) are r_V = 0.79 ± 0.12, r_M = 0.38 ± 0.09 and r_V = 0.79 ± 0.13, r_M = 0.38 ± 0.07, respectively. The complete spectral assignment in term of compositional and configurational sequences of these copolymers were done with the help of distortionless enhancement by polarization transfer (DEPT), two‐dimensional heteronuclear single quantum coherence spectroscopy (HSQC). Total correlated spectroscopy (TOCSY) experiment was used to assign the various three‐bond ¹H‐¹H couplings in the V/M copolymer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3232–3238, 2003     

Adiabatic compressibility of polyelectrolytes: Poly(N-dimethylaminoethyl methacrylate) and its copolymer with acrylic acid

The adiabatic compressibility of poly(N-dimethylaminoethyl methacrylate) and of three copolymers of N-dimethylaminoethyl methacrylate and acrylic acid, ranging in composition from 33 to 58 mole-% amino groups, has been studied. The ?V of the polymer shows a slight decrease (2.4 cc/mole), while the ?K is found to have increased considerably (51 × 10^?4 cc bar^?1 mole^?1) compared to that of the monomer. The latter is apparently due to the more compressible nature of the polymer than that of its monomer. The experimentally observed ?K₂⁰ and ?V₂⁰ values for the three copolymers containing 58%, 43%, and 33% amino groups are ?2.5 × 10^?4 cc bar^?1 mole^?1 and 164.5 cc/mole, ?32 × 10^?4 cc bar^?1 mole^?1 and 177.5 cc/mole, and ?55 × 10^?4 cc bar^?1 mole^?1 and 211.3 cc/mole, respectively, whereas the calculated values are less by 19.4 × 10^?4 cc bar^?1 mole^?1 and 3.2 cc/mole, 49.5 × 10^?4 cc bar^?1 mole^?1 and 19.9 cc/mole, and 73 × 10^?4 cc bar^?1 mole^?1 and 16.4 cc/mole, respectively. This decrease is attributed to the interaction of acid and base groups in the molecules. The ?K₂⁰ and ?V₂⁰ values have been resolved into their ionic components ?K and ?V. Since the magnitude of electrostriction is higher in fully neutralized salt than in unneutralized salt, the ?K_2i⁰ and ?V_2i⁰ values are lower as expected. The difference in these values for the polybase and its salt is 23.7 × 10^?4 cc bar^?1 mole^?1 and 7.5 cc/mole, respectively, which may be due to the electrostrictive effect. In excess NaCl (1.0M), the magnitude of electrostriction is somewhat reduced and ?V_2i⁰ and ?V_2i⁰ approach values more or less equal to those of the unneutralized polymer. The 100% neutralized hydrochloride salt of poly(N-dimethylaminoethyl methacrylate) shows greatly increased reduced viscosity over that of the feebly basic parent polymer due to the characteristic polyelectrolytic expansion in dilute aqueous solution. The copolymer containing excess amount of amino groups (58%) shows similar behavior, while the other two copolymers containing fewer amino groups (43% and 33%) show a contraction of chains, which may be ascribed in interaction of the carboxyl ions that are freshly formed on dilution with the amino groups in the copolymer chain.     

Synthesis and characterization of perfluorinated acrylate–methyl methacrylate copolymers

A novel perfluorinated acrylic monomer 3,5‐bis(perfluorobenzyloxy)benzyl acrylate (FM) with perfluorinated aromatic units was synthesized with 3,5‐bis(perfluorobenzyl)oxybenzyl alcohol, acryloyl chloride, and triethylamine. Copolymers of FM monomer with methyl methacrylate (MMA) were prepared via free‐radical polymerization at 80°C in toluene with 2,2′‐azobisisobutyronitrile as the initiator. The obtained copolymers were characterized by ¹H‐NMR and gel permeation chromatography. The monomer reactivity ratios for the monomer pair were calculated with the extended Kelen–Tüdos method. The reactivity ratios were found to be r₁ = 0.38 for FM, r₂ = 1.11 for MMA, and r₁r₂ < 1 for the pair FM–MMA. This shows that the system proceeded as random copolymerization. The thermal behavior of the copolymers was investigated by thermogravimetric analysis and differential scanning calorimetry (DSC). The copolymers had only one glass‐transition temperature, which changed from 46 to 78°C depending on the copolymer composition. Melting endotherms were not observed in the DSC traces; this indicated that all of the copolymers were completely amorphous. Copolymer films were prepared by spin coating, and contact angle measurements of water and ethylene glycol on the films indicated a high degree of hydrophobicity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Binary copolymerization of 4‐methyl‐1,3‐pentadiene with styrene,butadiene and isoprene catalysed by a titanium [OSSO]‐type catalyst

Binary copolymerization of 4‐methyl‐1,3‐pentadiene (4MPD) with styrene, butadiene and isoprene promoted by the titanium complex dichloro{1,4‐dithiabutanediyl‐2,2′‐bis[4,6‐bis(2‐phenyl‐2‐propyl)phenoxy]}titanium activated by methylaluminoxane is reported. All the copolymers are obtained in a wide range of composition and the molecular weight distributions obtained from gel permeation chromatographic analysis of the copolymers are coherent with the materials being copolymeric in nature. The copolymer microstructure was fully elucidated by means of ¹H NMR and ¹³C NMR spectroscopy. Differential scanning calorimetry shows an increase of glass transition temperature (T_g) with the amount of 4MPD in the copolymers with butadiene and isoprene, while in the copolymers with styrene T_g is increased on increasing the amount of styrene. © 2016 Society of Chemical Industry     

Studies on the copolymerization of methyl methacrylate and N-aryl maleimides

This article describes the synthesis and characterization of copolymers of methyl methacrylate (MMA) and N-4-chlorophenyl maleimide (PC)/N-3-chlorophenyl maleimide (MC). The copolymers were synthesized by varying the mole fraction of N-aryl maleimides from 0.1 to 0.5 in the initial feed using azobisisobutyronitrile (AIBN) as an initiator and tetrahydrofuran (THF) as the solvent. The copolymer composition was determined from the ¹H-NMR spectra by taking the ratio of proton resonance signals due to methoxy protons (δ = 3.59 ppm) of MMA and aromatic protons (δ = 7.2–7.4 ppm) of N-aryl maleimides. The reactivity ratios for MMA–PC and MMA–MC copolymers were found to be 0.952 (r₁), 0.029 (r₂) and 0.833 (r₁) and 0.033 (r₂), respectively. Thermal characterization of the copolymers was done using differential scanning calorimetry (DSC) and dynamic thermo-gravimetry. Initial decomposition temperature and glass transition temperature increased with increasing mole fraction of N-aryl maleimide content in the copolymers. © 1996 John Wiley & Sons, Inc.     

Synthesis and characterization of proccessible polyaniline derivatives for corrosion inhibition

This article reports the synthesis and characterization of copolymers based on aniline and substituted anilines by using dodecylbenzene sulfonic acid as a dopant. The copolymers were soluble in organic solvents, such as methanol, ethanol, isopropanol, N‐methylpyrrolidinone, dimethylsulphoxide, and have conductivity of the order of 1.5 to 10^?7 S/cm depending upon the monomer ratios and extent of dopant used. The effect of substituents like 2‐methyl, 2‐ethyl, and 2‐isopropyl groups on the electrochemical, conductivity, thermal stability, solubilization, and spectroscopic behavior of the copolymers has been evaluated. The composition of the copolymers was determined by ¹H‐NMR spectroscopy. Corrosion inhibition behavior of the copolymers in 1.0N HCl has been evaluated using linear polarization resistance method and Tafel extrapolation method. The corrosion efficiency depends upon the copolymer composition and it increased with increasing amount of 2‐alkyl aniline in the feed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Copolymers of poly(arylene sulfide sulfone)/poly(ether sulfone): Synthesis,structure, and rheology properties

In order to overcome the poor flowability of poly(arylene sulfide sulfone) (PASS), we introduced ether bonds into the polymer main chain. A series poly(arylene ether sulfide sulfone) copolymers (PAESS) containing different proportion of ether bonds were synthesized with 4,4′‐dichlorodiphenyl sulfone (DCDPS), sodium sulfide (Na₂S·xH₂O), and 4,4′‐dihydroxydiphenyl ether (DHDPE). The copolymers were characterized by Fourier transform infrared (FTIR), ¹H‐nuclear magnetic resonance (NMR), differential scanning calorimetry, dynamic mechanical analysis (DMA), and rheometer. The results of FTIR and ¹H‐NMR indicate the copolymers are synthesized successfully. PAESS were found to have excellent thermal properties with glass transition temperature (T_g) of 175.7–219.1 °C and 5% weight lost temperature were all above 420 °C. The tensile and DMA test indicates that these resultant copolymers have good mechanical properties with tensile strength of 60 MPa and storage modulus of 1.5 GPa. From the results of rheology properties testing, we found that the melt stability and melt flowability of PASS were improved distinctly from 25,470 Pa s down to 355 Pa s with the incorporation of ether bonds. That will be quite beneficial to the processing of PASS, especially for the thermoforming of precision products. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46534.     

Copolymerization of 4-cyanophenyl acrylate with methyl methacrylate: synthesis, characterization and determination of monomer reactivity ratios

A novel acrylic monomer, 4-cyanophenyl acrylate (CPA) was synthesized by reacting 4-cyanophenol dissolved in methyl ethyl ketone with acryloyl chloride in the presence of triethylamine as a catalyst. Copolymers of CPA with methyl methacrylate (MMA) at different composition was prepared by free radical solution polymerization at 70 ± 1 °C using benzoyl peroxide as an initiator. The copolymers were characterized by FT-IR, ¹H-NMR and ¹³C-NMR spectroscopic techniques. The solubility tests were checked in various polar and non polar solvents. The molecular weight and polydispersity indices of the copolymers were estimated by using gel permeation chromatography. The glass transition temperature of the copolymers increases with increases MMA content. The thermal stability of the copolymer increases with increases in mole fraction of CPA content in the copolymer. The copolymer composition was determined by using ¹H-NMR spectra. The monomer reactivity ratios determined by the application of linearization methods such Fineman–Ross (r ₁ = 0.535, r ₂ = 0. 0.632), Kelen–Tudos (r ₁ = 0.422, r ₂ = 0.665) and extended Kelen–Tudos methods (r ₁ = 0.506, r ₂ = 0. 0.695).     

Enhancement of mechanical and optical performance of commercial polystyrenes by blending with siloxane‐based copolymers

Well‐defined poly(styrene‐block ‐dimethylsiloxane) copolymers (PS‐b ‐PDMS) with low polydispersity index (M_w /M_n ) and different compositions were synthesized by sequential anionic polymerization of styrene (S) and hexamethyl(ciclotrisiloxane) (D₃) monomers. Synthesized PS‐b ‐PDMS copolymers were characterized by ¹H‐nuclear magnetic resonance, size exclusion chromatography, Fourier transform infrared spectroscopy, and transmission electron microscopy. The physicochemical characterization determined that block copolymers have molar mass values close to ～135,000 g mol^?1, narrow M_w /M_n < 1.3, and chemical composition ranging from low to intermediate PDMS content. Blends of these copolymers with a commercial polystyrene (PS) were obtained by melt mixing and subsequently injection. Films obtained were flexible, and showed lower transparency than the original PS matrix. On the other hand, a 10 wt % incorporation of PS‐b ‐PDMS copolymers leads to better mechanical performance by enhancing elongation at break (～8.8 times higher) and opacity values (～18 times higher). In addition, UV–Vis barrier capacity of the resulting blends is also increased (up to 400% higher). © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45122.     

Study on the synthesis of perfluorovinyl-sulfonic functional monomer and its copolymerization with tetrafluoroethylene

Tetrafiuoroethylene (TFE) and hexafluoropropylene (HFP) were subjected to reactions with freshly distilled sulfur trioxide to obtain 1-fluorosulfonyldifluoro-acetylfluoride (FSDFAF, yield 65–70%) and pentafluoro-2-propenylfluorosulfate (PPFS, yield up to 50%). A subsequent reaction of FSDFAF with PPFS under anhydrous conditions led to a preparation of 2-(1-pentafluoro-2-propenyloxy)tetrafluoroethanesulfonyl fluoride (PPOTESF, yield 40–41%) whose structure was proved by both infrared (IR) spectroscopy and nuclear magnetic resonance (¹⁹F NMR). TFE was copolymerized with PPOTESF in bulk by using a free radical initiator of the hydrocarbon type at a temperature of 50°C. Various TFE/PPOTESF mole ratios were employed and the presence of sulfonyl fluoride (? SO₂F) functional groups in the copolymers was proven by IR spectroscopy. The copolymers were subjected to alkaline hydrolysis and the ? SO₂F content was found not to exceed 0.70–0.80 mEq/g with polymer yields in the range of 11–31%. The reactivity ratios r₁ and r₂ related to TFE and PPOTESF, respectively, were determined by using the Fineman-Ross method. A random distribution of PPOTESF units along the polymeric chain, consisting mainly of TFE fragments, was found to exist. The copolymers had melting temperatures 40–45°C lower than polytetrafluoroethylene and were thermally stable to 305–315°C. © 1993 John Wiley & Sons, Inc.     

Synthesis and characterization of ABA‐type block copolymers of trimethylene carbonate and ϵ‐caprolactone

This paper describes the synthesis of a series of ABA‐type triblock copolymers of trimethylene carbonate and ?‐caprolactone with various molar ratios and analyses the thermal and mechanical properties of the resulting copolymers. The structures of the triblock copolymers were characterized by ¹H and ¹³C nuclear magnetic resonance spectroscopy, FT‐IR spectroscopy and gel permeation chromatography. Results obtained from the various characterization methods proves the successful synthesis of block copolymers of trimethylene carbonate and ?‐caprolactone. The thermal properties of the block copolymers were investigated by differential scanning calorimetry. The T_m and ΔH_m values of the copolymers decrease with increasing content of trimethylene carbonate units. Two T_gs were found in the copolymers. Furthermore, both of the T_g values increased with increasing content of trimethylene carbonate units. The mechanical properties of the resulting copolymers were studied by using a tensile tester. The results indicated that the mechanical properties of the block copolymers are related to the molar ratio of trimethylene carbonate and ?‐caprolactone in the copolymers, as well as the molecular weights of the resulting copolymers. The block copolymer with a molar composition of 50/50 possessed the highest tensile stress at maximum and modulus of elasticity. Block copolymers possessing different properties could be obtained by adjusting the copolymer compositions. Copyright © 2004 Society of Chemical Industry     

Modified polyacrylamide containing phenylsulfonamide and betaine sulfonate with excellent viscoelasticity for EOR

The monomers containing phenylsulfonamide N-allyl-4-methylbenzenesulfonamide (TCAP) and N,N-diallyl-4-methyl benzenesulfonamide (TCDAP) were copolymerized with acrylamide (AM), acrylic acid (AA), and 3-(3-methacrylamidopropyl-dimethylammonio)-propane-1-sulfonate (MDPS), respectively, through free-radical micellar copolymerization in deionized water for enhanced oil recovery (EOR). Then, the effect of the synthesis conditions was investigated simultaneously; the copolymers were characterized by Fourier transform infraredFTIR, nuclear magnetic resonance, scanning electron microscopy, and thermogravimetric analysis. It was found that the thickening function, high-temperature resistance (120 °C), and anti-shear ability were improved significantly. It was also found that the copolymers had excellent viscoelasticity at the lower shear frequencies. When the copolymers were dissolved in 10,000 mg L⁻¹ NaCl, 2000 mg L⁻¹ CaCl₂, and 2000 mg L⁻¹ MgCl₂ solutions, the viscosity retention rates of AM/AA/TCAP/MDPS and AM/AA/TCDAP/MDPS were 13.3, 11.1, 10.6% and 18.6, 15.2, 11.7%, respectively. In addition, the copolymers for EOR at 60 °C were 11.4 and 13.8%, respectively, which demonstrated that the copolymers possessed excellent performance for potential application in EOR. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47971.     

Microstructure analysis of N‐vinyl‐2‐pyrrolidone/vinyl acetate copolymers by NMR spectroscopy

N‐Vinyl‐2‐pyrrolidone (V) and vinyl acetate (A) copolymers of different compositions were synthesized by free radical bulk polymerization. The copolymer composition of these copolymers was determined using quantitative ¹³C{¹H} NMR spectra. The reactivity ratios for these comonomers were determined using the Kelen–Tudos (KT) and non‐linear least‐square error‐in‐variable (EVM) methods. The reactivity ratios calculated from the KT and EVM methods are r_V = 2.86 ± 0.16, r_A = 0.36 ± 0.09 and r_V = 2.56, r_A = 0.33, respectively. ¹H, ¹³C{¹H} and ¹H–¹³C heteronuclear shift correlation spectroscopy (HSQC) and ¹H–¹H homonuclear total correlation spectroscopy (TOCSY) were used for the compositional and configurational assignments of V/A copolymers. The ¹³C distortionless enhancement by polarization transfer (DEPT) technique was used to resolve the methine, methylene and methyl resonance signals in the V/A copolymers. © 2002 Society of Chemical Industry