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1.
Summary The methacrylic monomer, 4-biphenylmethacrylate (BPM) was synthesized by reacting 4-biphenyl phenol dissolved in ethyl methyl
ketone (EMK) with methacryloyl chloride in presence of triethylamine as a catalyst. The copolymers of BPM 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 BPM ranging
from 0.15 to 0.9 in the feed. 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 BPM content. The thermogravimetric analysis of the polymers showed that the thermal
stability of the copolymer increases with BPM 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 (r1=0.392 ± 0.006, r2 = 0.358 ± 0.007, Kelen-Tudos (r1= 0.398 ± 0.004, r2= 0.365 ± 0.013) and extended Kelen-Tudos methods (r1= 0.394 ± 0.004, r2= 0.352 ± 0.006). 相似文献
2.
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). 相似文献
3.
《国际聚合物材料杂志》2012,61(8):542-561
The synthesis and free radical homopolymerization of N-4-azodiphenylmaleimide (ADPMI) and copolymerization of methyl methacrylate (MMA) and styrene (ST) with ADPMI using an AIBN initiator were performed in THF solvent at 70°C. A series of copolymers, ADPMI-MMA and ADPMI-ST, were prepared using different feed ratios of comonomers. The polymer samples have been characterized by solubility tests, intrinsic viscosity measurements, FT-IR, 1H-NMR spectral analysis, and thermo-gravimetric analysis. The values of monomer reactivity ratios r1 and r2 determined by Fineman-Ross and Kelen-Tudos methods are 0.16 and 0.63, and 0.26 and 0.25 in ADPMI/MMA and ADPMI/ST systems, respectively. Alfrey-Price Q-e values for ADPMI are Q = 2.27 and e = 1.92, and 0.41 and 1.949 for ADPMI/MMA and ADPMI/ST systems, respectively. It was found that the initial and final decomposition temperatures increased with the increase of ADPMI content in the copolymer samples. 相似文献
4.
《国际聚合物材料杂志》2012,61(4):421-435
The free radical copolymerization of methyl methacrylate (MMA) or styrene (St) with N-(4-carboxyphenyl)maleimide (CPMI) was carried with AIBN as an initiator in THF solvent at 80°C. A series of copolymers of MMA and St with CPMI were prepared using different feed ratios of comonomers. The values of monomer reactivity ratios (r1, r2) determined by Fineman-Ross and Kelen-Tudos methods are 0.26 and 2.51 in the CPMI/MMA system and 0.08 and 0.22 in the CPMI/St system. Alfrey–Price Q-e values for CPMI were calculated as Q = 1.05 and e = 0.41 in the CPMI/MMA system and Q = 1.21 and e = 0.91 in the CPMI/St system. The polymer samples have been characterized by solubility tests, intrinsic viscosity measurements, FT-IR and 1H-NMR spectral analysis, and thermo-gravimetric analysis. It was found that the initial and final decomposition temperatures increased with increasing the amount of CPMI in the copolymer. The integral procedural decomposition temperature and energy of activation of thermal degradation have also been reported. 相似文献
5.
《国际聚合物材料杂志》2012,61(3):307-326
The free radical copolymerizations of methyl methacrylate (MMA), ethyl acrylate (EA), and butyl acrylate (BA) with N-2-Anisylmaleimide (AMI), initiated by AIBN, were performed in THF solvent at 65°C. A series of copolymers of AMI-MMA, AMI-EA, and AMI-BA were prepared using different feed ratios of comonomers. The polymer samples have been characterized by solubility tests, intrinsic viscosity measurements, FT-IR, and 1H-NMR spectral analysis, and thermo-gravimetric analysis. The values of monomer reactivity ratios r1 and r2 determined by Fineman-Ross and Kelen-Tudos methods are 0.43 and 0.42 in AMI/MMA, 0.72 and 0.62 in AMI/EA and 0.76 and 0.72 in AMI/BA systems. Alfrey-Price Q-e values for AMI are Q = 3.13 and e = 1.71 in AMI/MMA, Q = 1.10 and e = 1.46 in AMI/EA and Q = 1.02 and e = 1.63 in AMI/BA systems. It was found that the initial and final decomposition temperature increased with increasing the component of AMI in the copolymer. 相似文献
6.
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. 相似文献
7.
The article describes the synthesis and characterization of N‐(4‐methoxy‐3‐chlorophenyl) itaconimide (MCPI) and N‐(2‐methoxy‐5‐chlorophenyl) itaconimide (OMCPI) obtained by reacting itaconic anhydride with 4‐methoxy‐3‐chloroanisidine and 2‐methoxy‐5‐chloroanisidine, respectively. Structural and thermal characterization of MCPI and OMCPI monomers was done by using 1H NMR, FTIR, and differential scanning calorimetry (DSC). Copolymerization of MCPI or OMCPI with methyl methacrylate (MMA) in solution was carried out at 60°C using AIBN as an initiator and THF as solvent. Feed compositions having varying mole fractions of MCPI and OMCPI ranging from 0.1 to 0.5 were taken to prepare copolymers. Copolymerizations were terminated at low percentage conversion. Structural characterization of copolymers was done by FTIR, 1H NMR, and elemental analysis and percent nitrogen content was used to calculate the copolymer composition. The monomer reactivity ratios for MMA–MCPI copolymers were found to be r1 (MMA) = 0.32 ± 0.03 and r2 (MCPI) = 1.54 ± 0.05 and that for MMA–OMCPI copolymers were r1 (MMA) = 0.15 ± 0.02 and r2 (OMCPI) = 1.23 ± 0.18. The intrinsic viscosity [η] of the copolymers decreased with increasing mole fraction of MCPI/or OMCPI. The glass transition temperature as determined from DSC scans was found to increase with increasing amounts of OMPCI in copolymers. A significant improvement in the char yield as determined by thermogravimetry was observed upon copolymerization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2391–2398, 2006 相似文献
8.
《国际聚合物材料杂志》2012,61(8):519-530
Copolymers of 4-cinnamoyl phenyl methacrylate (4-CPMA) and n-butyl methacrylate (BMA) were prepared in a methyl ethyl ketone (MEK) solution with benzoyl peroxide (BPO) as an initiator at 70°C. They were characterized with UV, IR, 1H-NMR, 13C-NMR, TGA, DSC and gel permeation chromatography. Copolymers were prepared by using different feed ratio of monomers. The monomer reactivity ratios determined by the method of Kelen-Tudos (K-T) were r1 (CPMA) = 2.32, r2 (BMA) = 0.56. The glass transition temperature of the copolymer shows a single Tg indicating the formation of random copolymer for all of the monomer feed composition. Thermogravimetric analysis in air has shown that the initial decomposition temperature of the copolymer was above 220°C. The photocrosslinking properties of the copolymer were examined by UV irradiation with polymer film. 相似文献
9.
P.S. Vijayanand S. Kato S. Satokawa M. Kishimoto T. Kojima 《Reactive and Functional Polymers》2009,69(6):333-340
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 (r1 = 0.520, r2 = 2.521), Kelen–Tudos (r1 = 0.629, r2 = 2.554) and extended Kelen–Tudos methods (r1 = 0.600, r2 = 2.502). 相似文献
10.
Glycidyl methacrylate (GMA) and methyl methacrylate (MMA) copolymers were synthesized by atom transfer radical polymerization (ATRP). The effect of different molar fractions of GMA, ranging from 0.28 to 1.0, on the polymer polydispersity index (weight‐average molecular weight/number‐average molecular weight) as the indicator of a controlled process was investigated at 70°C, with ethyl 2‐bromoisobutyrate as an initiator and 4,4′‐dinonyl‐2,2′‐bipyridyne (dNbpy)/CuBr as a catalyst system in anisole. The monomer reactivity ratios (r values) were obtained by the application of the conventional linearization Fineman–Ross method (rGMA = 1.24 ± 0.02 and rMMA = 0.85 ± 0.03) and by the Mayo–Lewis method (rGMA = 1.19 ± 0.04 and rMMA = 0.86 ± 0.03). The molecular weights and polydispersities of the copolymers exhibited a linear increase with GMA content. The copolymer compositions were determined by 1H‐NMR and showed a domination of syndiotactic structures. The glass‐transition temperatures (Tg) of the copolymers analyzed by differential scanning calorimetry (DSC) decreased in the range 105–65°C with increasing GMA units. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
11.
Reactivity ratios and copolymer properties of 2‐(diisopropylamino)ethyl methacrylate with methyl methacrylate and styrene
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Free radical copolymerization kinetics of 2‐(diisopropylamino)ethyl methacrylate (DPA) with styrene (ST) or methyl methacrylate (MMA) was investigated and the corresponding copolymers obtained were characterized. Polymerization was performed using tert‐butylperoxy‐2‐ethylhexanoate (0.01 mol dm?3) as initiator, isothermally (70 °C) to low conversions (<10 wt%) in a wide range of copolymer compositions (10 mol% steps). The reactivity ratios of the monomers were calculated using linear Kelen–Tüd?s (KT) and nonlinear Tidwell–Mortimer (TM) methods. The reactivity ratios for MMA/DPA were found to be r1 = 0.99 and r2 = 1.00 (KT), r1 = 0.99 and r2 = 1.03 (TM); for the ST/DPA system r1 = 2.74, r2 = 0.54 (KT) and r1 = 2.48, r2 = 0.49 (TM). It can be concluded that copolymerization of MMA with DPA is ideal while copolymerization of ST with DPA has a small but noticeable tendency for block copolymer building. The probabilities for formations of dyad and triad monomer sequences dependent on monomer compositions were calculated from the obtained reactivity ratios. The molar mass distribution, thermal stability and glass transition temperatures of synthesized copolymers were determined. Hydrophobicity of copolymers depending on the composition was determined using contact angle measurements, decreasing from hydrophobic polystyrene and poly(methyl methacrylate) to hydrophilic DPA. Copolymerization reactivity ratios are crucial for the control of copolymer structural properties and conversion heterogeneity that greatly influence the applications of copolymers as rheology modifiers of lubricating oils or in drug delivery systems. © 2015 Society of Chemical Industry 相似文献
12.
This article describes the synthesis and characterization of N-(3-methoxyphenyl) itaconimide (MAI) and N-(4-methoxyphenyl) itaconimide (PAI) obtained by the reaction of itaconic anhydride with m-anisidine and p-anisidine, respectively. Structural and thermal characterization of MAI and PAI monomers was performed with Fourier transform infrared (FTIR), 1H-NMR, differential scanning calorimetry (DSC), and thermogravimetric analysis. Copolymerization of methyl methacrylate (MMA) with various amounts of MAI or PAI ranging from 0.1 to 0.5 was performed in solution with azobisisobutyronitrile as an initiator. Structural and molecular characterization of copolymers was performed with FTIR, 1H-NMR, elemental analysis, and gel permeation chromatography. The nitrogen percentage was used to calculate the copolymer composition. The monomer reactivity ratios for MMA–MAI copolymers were found to be 1.00 ± 0.01 for MMA and 0.99 ± 0.07 for MAI; those for MMA–PAI copolymers were 0.93 ± 0.02 for MMA and 1.11 ± 0.10 for PAI. The molecular weights of the copolymers were in the range of 0.94–9.7 × 103 (number-average molecular weight) and 3.3–101.8 × 103 (weight-average molecular weight), with polydispersity indices in the range of 1.5–4.1. The molecular weight decreased with the increasing molar fraction of imide in the polymer backbone. The glass-transition temperature, as determined from DSC scans, increased with increasing amounts of itaconimides in the copolymers. A significant improvement in the char yield, as determined by thermogravimetry, was observed upon copolymerization. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
13.
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 相似文献
14.
This study describes the synthesis, characterization, and thermal behavior of copolymers of methyl methacrylate (MMA) and N‐p‐tolyl itaconimide (PTI)/N‐phenyl itaconimide (I). Homopolymerization and copolymerization of N‐(phenyl/p‐tolyl) itaconimide with MMA was carried out by use of various mole fractions of N‐aryl itaconimide in the initial feed from 0.1 to 0.5, using azobisisobutyronitrile as an initiator and tetrahydrofuran as the solvent. The copolymer composition was determined by 1H‐NMR spectroscopy using the proton resonance signals attributed to –OCH3 of MMA (δ = 3.5–3.8 ppm) and the aromatic protons (δ = 7.0–7.5 ppm) of N‐aryl itaconimide. The reactivity ratios of the monomers were found to be r1 (PTI) = 1.33 ± 0.05/r2 (MMA) = 0.24 ± 0.03 and r1 (I) = 1.465 ± 0.035/r2 (MMA) = 0.385 ± 0.005. The molecular weight of the copolymers decreased with increasing mole fraction of N‐aryl itaconimide in the copolymers. Glass‐transition temperature (Tg) and thermal stability of PMMA increased with increasing amounts of itaconimides in the polymer backbone. A significant increase in the percentage char yield at 700°C was observed on incorporation of a low mole fraction of N‐aryl itaconimides. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1195–1202, 2003 相似文献
15.
Synthesis of imide‐based methacrylic monomers and their copolymerization with methyl methacrylate: monomer reactivity ratios and heat resistance properties
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The newly designed methacrylic monomer series 4‐phthalimidocyclohexyl methacrylate (PCMA ), 4‐hexahydrophthalimidocyclohexyl methacrylate (HPCMA) and 4‐hexahydro‐3,6‐methanophthalimidocyclohexyl methacrylate (HMPCMA) were synthesized. Their homopolymers and methyl methacrylate (MMA) based copolymer series were polymerized by free‐radical polymerization. The copolymer compositions were characterized using 1H NMR spectra. The monomer reactivity ratios were calculated employing the Fineman?Ross (F‐T) and Kelen?Tüdös (K‐T) methods at low conversion. The values of r1 and r2 obtained by the F‐T and K‐T methods appear to be in close agreement (their average values are r1 = 1.3061 and r2 = 0.7336 for poly(PCMA‐co‐MMA), r1 = 1.5169 and r2 = 0.6840 for poly(HPCMA‐co‐MMA), r1 = 1.7748 and r2 = 0.5664 for poly(HMPCMA‐co‐MMA)) . The thermal stabilities and thermomechanical characteristics of the homopolymer and copolymer series were investigated by differential scanning calorimetry, thermogravimetric analysis and dynamic mechanical thermal analysis. © 2018 Society of Chemical Industry 相似文献
16.
The synthesis, characterization, and thermal properties of copolymers of methyl methacrylate (MMA) and N‐(p‐carboxyphenyl) methacrylamide/acrylamide (CPMA/CPA) are described. The copolymerization was carried out in solution by taking different mole fractions (0.1–0.5) of CPMA/CPA in the initial feed using azobisisobutyronitrile as an initiator and dimethylformamide as a solvent at 60°C. The copolymer composition was determined from 1H‐NMR spectra by taking the ratio of the proton resonance signal due to the OCH3 of MMA (δ = 3.59 ppm) and the aromatic protons (δ = 7.6–7.8 ppm) of CPMA/CPA. The monomer reactivity ratios of MMA:CPMA and MMA:CPA were determined using the Fineman Ross and Kelen Tudos methods and were found to be 1.32 ± 0.01 [MMA], 1.11 ± 0.02 [CPMA], 2.60 ± 0.01 [MMA], and 0.20 ± 0.01 [CPA]. Incorporation of these comonomers in the MMA backbone resulted in an improvement in the glass‐transition temperature and thermal stability. The percent char also increased with the increase of CPMA/CPA content in the copolymers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 259–267, 2000 相似文献
17.
C. P. Pathak 《大分子材料与工程》1991,184(1):147-155
Hexyl α-chloroacrylate (HCA) and cyclohexyl α-chloroacrylate (CCA) have been copolymerized with methyl methacrylate (MMA) in toluene at 55°C using azobisisobutyronitrile (AIBN) as initiator. Copolymer compositions have been determined both by 1H NMR and elemental analyses. For copolymerization of MMA (M1) with HCA (M2), the reactivity ratios (RR) are r1 = 0.47 ± 0.19 and r2 = 0.81 ± 0.51 and with CCA the values are r1 = 0.76 ± 0.31 and r2 = 2.30 ± 1.73. Thermal properties of these copolymers have also been investigated. 相似文献
18.
The 1H-NMR spectra of poly(chloroprene-methyl methacrylate) which was copolymerized with ethylaluminum dichloride (EtAlCl2) and vanadyl trichloride (VOCl3) were measured with the radical copolymers. The split signals of the OCH3 and α-CH3 protons in the spectra were assigned to triads and pentads with methyl methacrylate as a center, respectively, and the fomer concentrations were in reasonable agreement with the latter concentrations in triads. Moreover, it was found that the α-CH3 signal was split into peaks of different tacticity when the mole fractional ratio of methyl methacrylate (MMA) to chloroprene (CP) in the copolymer was approximately 3.0 or greater. 相似文献
19.
Methyl methacrylate/vinylidene chloride (M/V) copolymers of different monomer concentrations were prepared by photopolymerization using the uranyl ion as photosensitizer. The copolymer composition was determined by chlorine estimation of the copolymers. The complete assignment of the 13C{1H} NMR spectra of these copolymers is made by comparison with the spectra of poly(methyl methacrylate) and observing the changes in the intensities of the resonances with copolymer composition. The quaternary carbon of V- and M- center resonances were used for determining the sequence in terms of the distribution of V- and M- centered triads. The triad fractions thus obtained were compared with theoretically determined triad concentrations. The Monte Carlo simulation method was also used for estimating the copolymerization behavior. The variation of V- and M- centered triad concentrations was reported as a function of fractional conversions. The comonomer reactivity ratios, determined by both Kelen Tudos and nonlinear error in variables methods are rV = 0.26 ± 0.04 and rM = 2.88 ± 0.23. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 373–381, 1998 相似文献
20.
Jatin N. Patel Mitul B. Dolia Kirit H. Patel Rajni M. Patel 《Journal of Polymer Research》2006,13(3):219-228
The methacrylate monomer 4-chloro-3‐methyl phenyl methacrylate (CMPM) was synthesized by reacting 4-chloro-3‐methyl phenol
with methacryloyl chloride. The homopolymer and various copolymers of CMPM with n-butyl methacrylate were synthesized by free-radical polymerization in toluene at 70°C using 2,2′-azobis(isobutyronitrile)
as the initiator. The CMPM monomer was characterized by Fourier transform IR and 1H-NMR studies. The copolymers were characterized by IR spectroscopy. The molecular weights (M
n and M
w) and the polydispersity index were obtained from gel permeation chromatography. The solubility and intrinsic viscosity of
the homopolymer and the copolymers are also discussed here. The copolymer composition obtained from UV spectra led to the
determination of reactivity ratios employing Fineman-Ross and Kelen-Tudos linearization methods. Thermogravimetric analyses
of the homopolymer and the copolymers were carried out under a nitrogen atmosphere. The homopolymer and the copolymers prepared
were tested for their antimicrobial activity against bacteria, fungi and yeasts. 相似文献