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1.
Summary The copolymerization of N-(2-hydroxyethyl)ethyleneimine, (HEEI) as nucleophilic monomer and maleic anhydride (MA) as electrophilic monomer in the absence of initiator in acetonitrile was investigated. Copolymers were characterized by IR, 1H-NMR and 13C-NMR spectroscopy. The copolymer composition depends on the monomer ratio in the feed, determined by 1H-NMR spectroscopy. The presence of MA bridges between copolymer chains was established by spectroscopic analysis. At lower temperature the yield and molecular weight of copolymers decrease as well as the MA unit content in the copolymer. 相似文献
2.
The polymerization of isatoic anhydride (electrophilic monomer) with N-(2-hydroxyethyl)ethyleneimine (nucleophilic monomer) was studied in the absence of added initiator at different feed monomer
concentrations, temperature, and time of copolymerization. The copolymers were characterized by FT-IR, 1H-NMR and 13C-NMR spectroscopy, and TGA. Based on spectroscopic data and copolymer composition, a copolymer structure was suggested.
Received: 25 April 1997/Revised: 11 August 1997/Accepted: 14 August 1997 相似文献
3.
Summary A novel difunctional random copolymer of maleic anhydride (MA) and n-octylacrylamide (acrylamide-n-octyl, AAO) with both anhydride and acrylamide moieties was synthesized. The copolymer had a molecular weight by SEC of between 950 and 1900 and a polydispersity of between 1.0 and 4.0. The performance of initiators azo-isobutyronitrile (AIBN) and benzoyl peroxide (BPO) at varying concentrations in solvent o-xylene were compared at four different initial MA:AAO ratios (7:3, 5:5, 6:4 and 4:6). The molecular weight of the synthesized copolymers at 7.5 mol % initiator concentration increased proportionally with the conversion at a 5:5 monomer ratio, whereas copolymerization at other initiator concentration and monomer ratios revealed a non-linear behavior. Characterization of monomer and copolymer on the basis of 1H-NMR and 13C-NMR is also reported. 相似文献
4.
Summary 1-(2-Hydroxyethyl)aziridine as nucleophilic monomer was copolymerized in the absence of an initiator under various experimental conditions with acrylamide as electrophilic monomer. All copolymers were characterized by elemental analysis, IR, and 1H-NMR spectroscopy. The viscosity measurements showed that the copolymers behave as polyelectrolytes. The copolymer composition was determined from elemental analysis and 1H-NMR spectra. 相似文献
5.
Summary
The copolymerization of p-chlorophenylmaleimide (1) as electrophilic monomer with 2-methyl-2-oxazoline (2) as nucleophilic monomer without initiator in solution under different experimental conditions was investigated. Copolymers
were characterized by FT-IR and 1H-NMR spectroscopy. The copolymer composition was determined from 1H-NMR spectra. Molecular weights ranged between 1700 and 5400 g/mol by vapor pressure osmometry.
Received: 27 September 1998/Revised version: 27 January 1999/Accepted: 28 January 1999 相似文献
6.
《国际聚合物材料杂志》2012,61(3-4):135-145
Abstract p-Chlorophenylmaleimide as an electrophilic monomer was copolymerized in the absence of initiator with 2-methylaziridine as nuclephilic monomer. The copolymers were characterized by elemental analysis, FT-IR, and 1H-NMR spectroscopy. The copolymer compositions were determined by chloro elemental analysis and 1H-NMR spectroscopy. 2-Methylaziridine is more reactive than p-chlorophenylmaleimide yielding statistical copolymers. Mn, determined by vapor pressure osmometry, varied between 3.000 and 6.700 g/mol. 相似文献
7.
Summary The copolymerization of 1-(2-hydroxyethyl)aziridine as nucleophilic monomer with N-phenylmaleimide and p-methoxyphenylmaleimide
as electrophilic monomer in the absence of an initiator in solution was investigated. Copolymerizations under different experimental
conditions were carried out. The copolymers were characterized by FT-IR and 1H-NMR spectroscopy. The copolymer compositions were determined by elemental analysis and 1H-NMR spectroscopy. Almost all products are statistical copolymers. 相似文献
8.
Summary A novel methacrylic monomer, 4-cyanophenyl methacrylate (CPM) was synthesized by reacting 4-cyanophenol dissolved in methyl
ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine as a catalyst. Copolymers of CPM with methyl
methacrylate(MMA) at different composition was prepared by free radical solution polymerization at 70±1 °C using benzoyl peroxide
as initiator. The copolymers were characterized by FT-IR, 1H-NMR and 13C-NMR spectroscopic techniques. The solubility of the polymers was tested in various polar and non polar solvents. The molecular
weight and polydispersity indices of the copolymers were determined using gel permeation chromatography. The glass transition
temperature of the copolymers increases with increase in mole fraction of MMA content. The thermal stability of the copolymer
increases with increases in mole fraction of CPM content in the copolymer. The copolymer composition was determined by using
1H-NMR spectroscopy. The monomer reactivity ratios estimated by the application of linearization methods such as Fineman-Ross
(r1=2.524±0.038, r2=0.502±0.015), Kelen-Tudos (r1=2.562±0.173, r2=0.487±0.005) and extended Kelen-Tudos methods (r1=2.735±0.128, r2=0.4915±0.007). 相似文献
9.
Homogeneous copolymers of N-vinylpyrrolidone (VP) and vinyl acetate (VA) which form clear aqueous solutions were prepared by free radical polymerization in a solution of isopropanol alcohol, using 2,2-azobisisobutyronitrile as an initiator. They were characterized by FTIR, 1H-NMR, and element analysis studies. The reactivity ratios of the monomer were computed by the Extended Kelen–Tüdós method at high conversions, using data from both 1H-NMR and elemental analysis studies. The reactivity ratios of VP and VA in a homogenous copolymer were observed to be very different from that of a heterogeneous copolymer. Additional information was obtained by finding out the sequence length distribution for copolymers. 相似文献
10.
Summary
Polyisoprene (PI) was pre-polymerized by using benzyl diethyldithiocarbamate (BDC) as an iniferter. The obtained PI was subsequently
used to react with methyl methacrylate (MMA) in order to investigate whether the relevant block copolymers can be achieved.
Results from 1H-NMR and GPC reveal that the PI-PMMA block copolymers were formed. This suggests that polymerization of isoprene through
the use of BDC proceeded via a (psuedo) “living” mechanism.
Received: 9 August 1999/Revised version: 27 September 1999/Accepted: 1 October 1999 相似文献
11.
Summary
The chemical shift in the 13C NMR spectra of copolymers of 2-chloroethyl vinyl ether (CEVE) and maleic anhydride (MA), and of n-butyl vinyl ether (BVE)
and MA is assigned. It is found that both copolymers are made of completely alternating monomer unit sequences and that the
proportion of cis linkage configuration at the cyclic MA units is 45 % and 47 % in the CEVE-MA copolymer and in the BVE-MA copolymer, respectively.
Depending on the relative orientation of the cyclic anhydride group, quasi “isotactic” and quasi “syndiotactic” tacticity
are considered, with quasi “syndiotactic” diads shielding the vinyl ether carbons more effectively.
Received: 19 April 1999/Accepted: 17 June 1999 相似文献
12.
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
13.
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
14.
Summary The binary and ternary copolymers are synthesized by free-radical initiated binary copolymerization of citraconic anhydride (CA) with acrylamide (AAm) and terpolymerization of acrylamide (AAm) – citraconic anhydride (CA) – vinyl acetate (VA) monomer system. Co- and terpolymerization were carried out in the presence of benzoyl peroxide (BPO) as an initiator at 70 °C in benzene under nitrogen atmosphere. Structure and monomer unit composition of the copolymers, obtained from a wide range of monomer feed were determined by elemental analysis. Structural peculiarities of synthesized PAAm, [poly (AAm-alt-CA)] and [poly(AAm-co-CA-co-VA)] were characterized by using Fourier Transform Infrared (FTIR), Uv–vis, 1H-NMR, X-ray diffraction (XRD), elemental analysis, analytical methods (titration methods) and viscometric measurements. 相似文献
15.
The copolymerization of 2-(3-mesityl-3-methylcyclobutyl)-2-ketoethyl methacrylate monomer with acrylonitrile and styrene were carried out in 1,4-dioxane solution at 60 ○C using AIBN as an initiator. The copolymers were characterized by Fourier transform infrared, 1H-NMR, and 13C-NMR spectroscopic techniques. Thermal properties of the polymers were also studied by thermogravimetric analysis and differential scanning calorimetry. The copolymer compositions were determined by elemental analysis and 1H-NMR technique. The monomer reactivity ratios were calculated by the application of conventional linearization methods as a result of Fineman–Ross and Kelen–Tüdös to less than 1 for both monomers. 相似文献
16.
Summary The configuration of citraconic anhydride units in p-chlorostyrene/citraconic anhydride copolymers prepared in methyl ethyl ketone at 50.0±0.1°C and the corresponding copolymer compositions and comonomer unit sequence distributions were determined over a range of comonomer feed mole fractions using 13C NMR spectroscopy. It was found that the ratio of Z (zusammen) to E (entgegen) configurations of citraconic anhydride units in these semi-alternating copolymers showed an overall tendency to increase with the degree of alternation of the monomer units. 相似文献
17.
A cardanol-based UV-curable vinyl ester (VE) monomer was prepared via simple esterification, and its successful synthesis was demonstrated by FTIR and 1H-NMR. In order to improve its rigidity, it was mixed with certain proportions of another reactive bio-based VE monomer, maleic anhydride modified dimer fatty acids polymerized glycidyl methacrylate (MA-m-DA-p-GMA) which had rigid and strong polar groups, and then a series of UV-cured copolymers were prepared from the two VE monomers. The UV curing process was monitored by FTIR analysis. The tensile and thermal properties of the cured copolymer films were also investigated. UV curing analysis demonstrated that the double bonds in the mixed VE could be converted to ultimate curing level within 40 s. Tensile tests showed the prepared copolymers had a tensile strength of 8.86 MPa. Dynamic mechanical analysis (DMA) revealed the copolymers had relatively high glass transition temperature (Tg) from 40 to 60 °C. Thermogravimetric analysis (TGA) showed the copolymers containing higher content of CDMA had higher thermal stability, and all copolymers’ main thermal initial decomposition temperatures were above 410 °C, indicating the copolymers had certain thermal stability. These copolymer films can be used as eco-friendly materials in coatings and other applications to replace the currently used petroleum-based polymers. 相似文献
18.
A series of copolymers were synthesized by chemically oxidative polymerization of p-phenylenediamine (PPD) and o-phenetidine (PHT) in acidic aqueous media. The polymerization yield, intrinsic viscosity, and solubility of the copolymers were comprehensively studied by changing the comonomer ratio, polymerization time and temperature, oxidant, monomer/oxidant ratio, and acidic medium. As-prepared fine powder of the PPD/PHT copolymers was characterized by FT-IR, UV-vis, high-resolution 1H-NMR, and DSC techniques. A circular dichroism technique was firstly used to characterize the macromolecular structure of the copolymers. The results showed that the oxidative copolymerization from PPD and PHT is exothermic and the resulting copolymers exhibit an enhanced solubility in most of the organic solvents as compared with poly(p-phenylenediamine), sometimes also with poly(o-phenetidine). The polymer obtained is a real copolymer containing PPD and PHT units, and the actual PPD/PHT ratio calculated by 1H-NMR spectra of the polymers is very close to the feed ratio. The DSC measurement indicates that the copolymers are amorphous and chemically instable at elevated temperature. 相似文献
19.
A copolymer of styrene and maleic anhydride was synthesized by free radical polymerization at 80°C using N,N‐dimethylformamide (DMF) as solvent and benzoylperoxide as initiator. The monomer feed ratio of styrene to maleic anhydride was varied in the range of 1 : 1 : to 3 : 1. The polymer yield was found to decrease with increase in styrene in the feed. The molecular weight of copolymers which were formed by taking styrene to maleic anhydride ratio of 1 : 1, 2 : 1, and 3 : 1, as determined by Ostwald Viscometery were about 1862, 2015, and 2276 respectively. The acid values of abovementioned three copolymers were found to be 480, 357, and 295, respectively. The typical viscosity values of 20% solids in ammonical solution of copolymers formed by taking feed ratios of Sty : MAn as 1 : 1 and 2 : 1 were 26 and 136 cp, respectively. For the feed ratio 3 : 1, a gel was formed. The synthesized copolymers were hydrolyzed by alkalis, namely, NaOH, KOH, and NH4OH. The dispersing ability of hydrolyzed styrene‐maleic anhydride (SMA) copolymers for dispersion of titanium dioxide was studied. The modified SMA copolymers were found to be effective dispersants for TiO2. Among the three alkalis studied, the Sodium salts of SMA were found to give better dispersion. The copolymer having a 1 : 1 feed ratio showed the best dispersing ability for TiO2 particles among the three ratios studied. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3194–3205, 2007 相似文献
20.
Ring-Opening copolymerization of epichlrohydrin (ECH) with maleic anhydride (MAn) was catalyzed by yttriun phosphenate in combination with triisobutylaluminum for the first time to give almost alternate copolymer, functional polyester. The yield and composition of the copolymer were affected by the reaction conditons, especially the initial monomer charge ratio. The overall activation energy of the copolymerization was estimated to be 19.Okeal/mol. Evidence for the structure of ECH-MAn copolymer prepared was obtained by IR adn1H-NMR. 相似文献