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1.
This work presents the synthesis by plasma and the characterization of polypyrrole–polyaniline–iodine copolymer thin films. The objective was to study the conditions to randomly copolymerize different and noncombinable monomers to create new copolymers with enhanced selective properties. The study was focused on the influence of the monomer mass ratio r on the structure of the copolymers. The monomer ratio r is important since it represents the contribution of each monomer to the structure and to the properties of the copolymer. The mainstream techniques used to characterize the plasma polymers were infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The electric conductivity was studied as a function of the relative humidity. The results indicated that the copolymers with iodine have better conductive properties at lower relative humidity and that the copolymers without iodine are more stable at moderately high temperatures. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 263–270, 2002  相似文献   

2.
Graft copolymers containing poly(ethylene oxide) side chain attached to maleic anhydride‐alt‐vinyl methyl ether (MA‐VME) copolymer were prepared by coupling MA‐VME and poly(ethylene glycol) monomethyl ether (MPEG) by esterification in DMF at 90°C. MPEG and dodecyl alcohol (DA) were grafted onto MA‐VME copolymer in o‐xylene at 140°C in the presence of p‐toluene sulfonic acid as catalyst. The molecular weights of MPEG were found to influence the rate of the grafting reaction and the final degree of conversion. The graft copolymers were characterized by IR, GPC, and 1H‐NMR. DSC was used to examine thermal properties of the graft copolymers. The analysis indicates that grafts have phase‐separated morphology with the backbone and the MPEG grafts forming separate phases. The properties in aqueous solutions of these grafts were studied with respect to aggregation behavior and viscometric properties. In aqueous solution, the polymers exhibited polyelectrolyte behavior (i.e., a dramatic increase of the viscosity upon neutralization). Graft copolymers with DA have lower viscosities. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1138–1148, 2002  相似文献   

3.
In the present study, first, maleic anhydride‐styrene (MA‐St), maleic anhydride‐allyl phenyl ether (MA‐APhE), maleic anhydride‐heptene‐1(MA‐Hp), and maleic anhydride‐allyl propionate (MA‐AP) copolymers have been synthesized in different solvents in the presence of azobisisobutyronitrile (AIBN) at 70°C. Then, these four copolymers have been reacted with aniline at 60°C in N,N‐dimethyl formamide (DMF), and maleamidic acid derivatives of these copolymers have been synthesized. Next, they have been obtained from their maleimide derivatives by heating under vacuum at 150°C. All these polymers have been characterized by Fourier Transform infrared spectroscopy (FTIR) and investigated their thermal properties by using differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA) methods. The analyses results showed that thermal properties of maleimide derivatives of maleic anhydride copolymers changed as depend on the neighbor monomers of maleic anhydride. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2250–2254, 2006  相似文献   

4.
Poly(2,6‐dimethyl‐1,4‐phenylene oxide)/polyamide 6 (PPO/PA6 30/70) blends were impact modified by addition of three kinds of maleated polystyrene‐based copolymers, i.e., maleated styrene‐ethylene‐butylene‐styrene copolymer (SEBS‐g‐MA), maleated methyl methacrylate‐butadiene‐styrene copolymer (MBS‐g‐MA), and maleated acrylonitrile‐butadiene‐styrene copolymer (ABS‐g‐MA). The mechanical properties, morphology and rheological behavior of the impact modified PPO/PA6 blends were investigated. The selective location of the maleated copolymers in one phase or at interface accounted for the different toughening effects of the maleated copolymer, which is closely related to their molecular structure and composition. SEBS‐g‐MA was uniformly dispersed in PPO phase and greatly toughened PPO/PA6 blends even at low temperature. MBS‐g‐MA particles were mainly dispersed in the PA6 phase and around the PPO phase, resulting in a significant enhancement of the notched Izod impact strength of PPO/PA6 blends from 45 J/m to 281 J/m at the MBS‐g‐MA content of 20 phr. In comparison, the ABS‐g‐MA was mainly dispersed in PA6 phase without much influencing the original mechanical properties of the PPO/PA6 blend. The different molecule structure and selective location of the maleated copolymers in the blends were reflected by the change of rheological behavior as well. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

5.
K. O'Leary 《Polymer》2004,45(19):6575-6585
Poly(n-alkyl acrylate) copolymer reactivity ratios were determined for n-alkyl acrylate monomers of various side-chain lengths n ranging from 6 to 22. Two sets of copolymers were synthesized to less than <10% conversion to evaluate the reactivity ratios. The first set included P(A10-co-A14), P(A10-co-A18), and P(A14-co-A18); while the second set consisted of P(A6-co-A12), P(A6-co-A22) and P(A12-co-A22). Copolymers were formed from monomer mixtures at 25 mol% intervals ranging from 0 through 100 mol%. 13C NMR was performed on the homo polymers and the low conversion copolymers to determine the reactivity ratios of the monomers in each copolymer system. It was determined that the reactivity ratios for all monomers examined here were approximately equal to one. Physical properties of the copolymers, including melting point, heat of fusion, and permeation as a function of temperature, of the low conversion polymers were compared to copolymers formed at 100% conversion to demonstrate that these properties are independent of conversion because no composition drift occurs during polymerization.  相似文献   

6.
Copolymers of aniline and toluidine were synthesized by oxidative chemical polymerization using different ratios of the monomers in the feed, and characterized by a number of techniques including UV–visible, IR, Raman, 1H NMR and EPR spectroscopies, as well as by thermogravimetric analysis and conductivity measurements. The properties of the copolymers are influenced by the amount of toluidine in the copolymer. Poly(o‐toluidine) and poly(m‐toluidine) are noticeably different in their solubility and conductivity. The copolymers show better solubilities than polyaniline but have lower conductivities. Differences in the properties of the salt and base forms of the copolymers are pointed out. Copyright © 2003 Society of Chemical Industry  相似文献   

7.
Poly(cyclopentene sulfone) (PCPS) and poly(bicycloheptene sulfone) (PBCHS) copolymers have been evaluated as potential positive electron beam resists which have good thermal properties and which show high sensitivity to ionizing radiation. It was found that thin copolymer films could be processed as resists but that films greater than 3000 Å thick cracked in the solvents used to dissolve the radiation-exposed regions. Incorporation of plasticizing additives did not improve the film properties. Films from low molecular weight polymer fractions cracked less in solvents, but higher radiation doses were required to offset the reduced sensitivity. This resulted in the formation of intractable residues in the exposed regions which appear to be crosslinked polymer. Bicycloheptene monomers with specific functional groups did not improve the properties of the copolymer films. Terpolymerization with α-olefins such as butene-1 and cis-2-butene plasticized these films and reduced their tendency to crack in solvents. Poly(cyclopentene sulfone–co–butene-1 sulfone) films were found to have the best properties, and 1.25-μ resist images could be etched in SiO2 layers at an exposure dose of 4 × 10?6 C/cm2 at 25KV. However, one important limitation of this terpolymer was the low dissolution rate ratio between the exposed and unexposed regions. Since straight-walled relief images are essential to the formation of high-resolution patterns, the usefulness of this terpolymer as an electron beam resist appears to be hindered by the limited choice of good solvents to maximize the dissolution rate ratio. PBCHS block terpolymers containing methyl methacrylate (MMA) or methacrylic acid (MAA) were synthesized to improve the solubility in solvents and to incorporate the properties of methacrylates. PBCHS–MMA films cracked in solvents after irradiation; PBCHS–MAA polymers were too insoluble to form resist films.  相似文献   

8.
The polyacrylonitrile‐methyl acrylate (AN/MA mole ratio 100/0–70/30) copolymers and copolymers (AN/MA mole ratio 85/15) containing up to 40 wt % of microencapsulated n‐octadecane (MicroPCMs) are synthesized in water. The MicroPCMs were incorporated at the step of polymerization. The effect of the MA mole ratio and MicroPCMs content on structures and properties of the copolymers were studied by using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR), scanning electronic microscope (SEM), differential scanning calorimetry (DSC), thermogravimetry analysis (TG), gel permeation chromatography (GPC), and X‐ray diffraction (XRD). The feeding ratio agreed well with the composition of the AN/MA copolymers. The copolymers are synthesized in the presence of MicroPCMs. The melting point moves to lower temperature (206°C), while the decomposition temperature moves to higher temperature (309°C) with increasing of the MA mole ratio and microcapsules content. The number–average molecular weight of the copolymer is ~30,000. The crystallinity of the copolymer decreases with increasing of the MA mole ratio and microcapsules content. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2776–2781, 2007  相似文献   

9.
Two novel organotin monomers, (N‐tri‐n‐butyltin) maleimide and m‐acryloylamino‐(tri‐n‐butyltin benzoate), were synthesized. Copolymerization of these two monomers with styrene was carried out in the bulk at 65°C using asobisisobutyronitrile as the free radical initiator. The monomers and copolymers were characterized by elemental analysis; the molecular weights of the copolymers were determined by GPC, solubility, IR, and 1H‐NMR spectral studies. The antibacterial activities of the synthesized organotin monomers and copolymers toward various types of bacteria were also reported. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 740–745, 2000  相似文献   

10.
A novel photosensitive monomer with a pendant photoreactive diethyldithiocarbamoyl group, VBDC, was synthesized and copolymerized with some vinyl monomers by AIBN. The copolymers obtained have efficient photocrosslinking abilities, and are thermally stable. Therefore, there was no loss of dithiocarbamoyl group during radical polymerization, and the polymerization proceeded through vinyl group. The degree of photocrosslinking was proportional to the concentration of the photosensitive group, but photosensitivity of the polymer was not. Water-soluble photoreactive copolymers, VBDC with AAm or MA, were also prepared. AAm copolymer has a good photosensitivity by only 3 mol % VBDC incorporation. Photocrosslinking yields of these polymers depend on the viscosity of original polymers except in the case of low concentration of VBDC. The relation between copolymer composition and glass transition temperature was also investigated. From the investigation of Tg, it was concluded that the copolymer structure largely affected on ΔTg. The mechanism of photocrosslinking was studied by photodecomposition of benzyl N, N-diethyldithiocarbamate, and the result that the decreases of sulfur content clearly related to photocrosslinking points was also obtained.  相似文献   

11.
In this article, we report on the antibacterial properties of a novel antimicrobial poly(citric acid-co-curcumin) polymer system that was prepared by a catalyst–free polyesterification process. The dual polymer of poly(citric acid-co-curcumin) was synthesized by varying the weight ratio of citric acid and curcumin monomers. Details of the synthesis, spectral (Fourier transform infrared, ultraviolet), thermal stability (Thermogravimetric analyses), and the morphological (Scanning electron microscopy/energy dispersive spectroscopy) characterization of dual polymers are presented in this scientific article. The UV–visible spectrometry was used to confirm the copolymerization of curcumin dispersion in the dual polymer systems. The presence of functional groups of copolymers was confirmed by Fourier transform infrared spectroscopy. The thermogravimetric analysis results indicated that poly(citric acid-co-curcumin) have a thermal stability up to 225°C. The ratios used were 1:0.25, 1:0.5, 1:0.75, and 1:1 and their antibacterial properties were studied with respect to their activity on gram-positive and gram-negative bacteria. This dual polymer was inoculated onto a Petri dish and its ability to inhibit the growth of Escherichia coli, Staphylococcus, Bacillus subtilis, Candida albicans (fungus), and Micrococcus luteus was evaluated using the bacterial disc method. Results indicated inhibition properties to increase with increasing curcumin content and the dual polymer with highest curcumin content showed excellent antimicrobial activities against both gram-negative and gram-positive microorganisms. Hence, it was clear that the developed dual polymers may be effectively used for antibacterial applications such as wound dressing.  相似文献   

12.
2-Phenylethyl acrylate (PEA) and 2-Phenylethyl methacrylate (PEMA) were synthesized by reacting 2-Phenyl ethanol with acryloyl and methacryloyl chloride respectively. Homopolymers and copolymers were prepared by free radical polymerization technique using benzoylperoxide as initiator. Copolymers of PEA and PEMA with methyl acrylate (MA) and N-vinyl pyrollidone (NVP) of different compositions were prepared. The monomers and polymers were characterized by IR and NMR techniques. Thermal stability of the polymers were determined by TG analysis. The composition of the copolymer was determined using 1H-NMR analysis. The reactivity ratios of the monomers were determined by the application of Finemann–Ross and Kelen–Tudos methods. The prepared copolymers were tested on leather for their pressure sensitive adhesive property.  相似文献   

13.
Alternate N-vinyl pyrrolidone/maleic anhydride (NVPMA) copolymers were obtained by radical solution polymerization in dioxane with various MA contents in the monomer feed. The conversion of each monomer was monitored by proton nuclear magnetic resonance spectroscopy (1H NMR), and the kinetics investigation showed that both monomers had identical polymerization rates if both monomers were present in the reaction mixture. The presence of excess NVP in the polymerization medium increased the kinetics of the polymerization and the molar masses of the resulting polymers. This increase was attributed to a cosolvent effect due to NVP, which is a better solvent for the polymer than dioxane. The hydrolysis rate constant of the polymers increased with pH, and NVPMA copolymers were more prone to hydrolysis (by a factor 10) than the methyl vinyl ether ones. Finally, the immobilization of bovin serum albumin (BSA) was investigated. A 25 mM phosphate buffer (pH 5.5) was the best medium to covalently bind 5 BSA molecules onto a 29 kDa NVPMA copolymer and 13 BSA molecules onto a 58 kDa sample, with grafting efficiencies > 90%. Noncovalent interactions with the hydrolyzed form of the polymer and BSA occured at pHs lower than the isoelectric point of BSA, and the resulting complexes were insoluble in water. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3327–3337, 2001  相似文献   

14.
Triblock copolymers containing polystyrene (PSt) and poly(4-acetoxystyrene) (PAcOSt) segments have been prepared by atom transfer radical polymerization (ATRP). In the first step one of the two monomers was polymerized in bulk using the initiating system α,α′-dibromo-p-xylene/CuBr/2,2′-bipyridine (1/1/3). Subsequently the resulting telechelic polymers with active bromo end group structures were used as macroinitiators for the polymerization of the second monomer under ATRP conditions. This process gave PAcOSt-PSt-PAcOSt and PSt-PAcOSt-PSt triblock copolymers with predetermined molecular weights and narrow molecular weight distributions. Polymerization of a mixture of equal molar amounts of the two monomers yielded a random copolymer with narrow molecular weight distribution. Received: 25 June 1997/Revised: 25 August 1997/Accepted: 8 September 1997  相似文献   

15.
The free-radical copolymerization of 2-methyl-N-1,3-thiazole-2-ylacrylamide monomer (TMA) with glycidyl methacrylate (GMA) was carried out in 1,4-dioxane at 65 ± 1 °C using azobisisobutironitril (AIBN) as an initiator. The copolymers were characterized by FTIR, 13C-NMR and 1H-NMR spectroscopic methods. The copolymer compositions were determined by elemental analysis. The weight-average and number-average molecular weights of the copolymers were obtained by gel permeation chromatography (GPC). The polydispersity indices of the polymers, determined with gel permeation chromatography, suggested a strong tendency for chain termination by disproportionation. Thermal properties of the polymers were also studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The monomer reactivity ratios were calculated according to the general copolymerization equation using Kelen–Tudos and Fineman–Ross linearization methods. The reactivity ratios indicated a tendency toward for alternation. The thermal decomposition activation energies of the polymers were evaluated by Ozawa method. The antibacterial and antifungal effects of the copolymers were also investigated on various bacteria and fungi. All the products showed moderate activity against different strains of bacteria and fungi.  相似文献   

16.
BACKGROUND: Poly(1‐amino‐2‐naphthol‐4‐sulfonic acid) and its copolymers with aniline are a new class of conducting polymers which can acquire intrinsic protonic doping ability, leading to the formation of highly soluble self‐doped homopolymers and copolymers. Free ? OH and ? NH2 groups in the polymer chain can combine with other functional groups that could be present in protective paints which can thus be successfully used as antistatic materials. RESULTS: This paper reports the formation of nanotubes of polyaniline on carrying out oxidative polymerization of aniline in the presence of 1‐amino‐2‐naphthol‐4‐sulfonic acid (ANSA) in p‐toluenesulfonic acid (PTSA) as an external dopant. The presence of ? SO3H groups in the ANSA comonomer allows the copolymer to acquire intrinsic protonic doping ability. The polymerization mechanism was investigated by analysing the 1H NMR, 13C NMR, Fourier transform infrared and X‐ray photoelectron spectra of the copolymers and homopolymers, which revealed the involvement of ? OH/? NH2 in the reaction mechanism. Scanning and transmission electron microscopy showed how the reaction route and the presence of a dopant can affect the morphology and size of the polymers. Static decay time measurements were also carried out on conducting copolymer films prepared by blending of 1 wt% of copolymers of ANSA and aniline with low‐density polyethylene (LDPE) which showed a static decay time of 0.1 to 0.31 s on dissipating a charge from 5000 to 500 V. CONCLUSION: Copolymers of ANSA with aniline were synthesized in different reaction media, leading to the formation of nanotubes and nanoparticles of copolymer. Blends of 1 wt% of PTSA‐ and self‐doped copolymers of ANSA and aniline with LDPE can be formulated into films with effective antistatic properties. Copyright © 2009 Society of Chemical Industry  相似文献   

17.
Poly(2‐aminobenzoic acid) and poly(3‐aminobenzoic acid) were synthesized by chemical polymerization of the respective monomers with aqueous 1M hydrochloric acid and 0.49M sodium hydroxide, using ammonium persulfate as an oxidizing agent. In addition, polymerization in an acid medium was carried out in the presence of metal ions, such as Cu(II), Ni(II), and Co(II). Poly(2‐aminobenzoic acid‐co‐aniline) and poly(3‐aminobenzoic acid‐co‐aniline) were synthesized by chemical copolymerization of aniline with 2‐ and 3‐aminobenzoic acids, respectively, in aqueous 1M hydrochloric acid. The copolymers were synthesized at several mole fractions of aniline in the feed and characterized by UV–visible and FTIR spectroscopy, the thermal stability, and the electrical conductivity. Metal ions, such as Cu(II), Ni(II), and Co(II), were incorporated into homo‐ and copolymers by the batch method. The percentage of metal ions in the polymers was higher in the copolymers than in the homopolymers. The thermal stability of the copolymers increased as the feed mole fraction of aniline decreased and varied with the incorporation of metal ions in the polymers. The electrical conductivity of the homo‐ and copolymers was measured, which ranged between 10?3 and 10?10 S cm?1. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2641–2648, 2003  相似文献   

18.
Itaconic anhydride was polymerized in the presence of a radical initiator under various conditions. The bulk polymerization at 75°C yielded polymer with molecular weight of more than 20000. The reactions of the resulting polymer with water and alcohols gave poly(itaconic acid) and its esters, respectively. The polymers prepared by such reactions were found to have similar thermal properties to those prepared by homopolymerizations of the respective itaconic acid derivatives. Poly(N-substituted itaconomic acid)s, which are difficult to obtain by direct polymerization of their monomers, were prepared by the reactions of poly(itacononic anhydride) with amines. Copolymerizations of itaconic anhydride with electron-donating monomers, styrene and isobutyl vinyl ether, gave alternating copolymers which were then converted by esterification to the respective copolymers of dialkyl itaconates with such electron-donating monomers.  相似文献   

19.
This paper studied the synthesis of a novel elastomeric copolymer electrolyte in an aqueous phase. The monomer, sodium allyl sulfonate (SAS), was dissolved in continuous aqueous phase and the second monomer, methyl acrylate (MA), was supplied from MA micelles as dispersed phase. The copolymerization of the two monomers took place in continuous aqueous phase. Confirmed by FTIR and 1H‐NMR, a binary copolymer electrolyte of MA and SAS, poly(MA‐co‐SAS), was obtained. The glass transition temperature of the copolymer was indicated as 20.4°C by DSC thermogram, thus, it behaves an elastomer in normal ambient temperature. The mechanical properties of the composite films consisting of both poly(MA‐co‐SAS) and Cu2+ ions or reduced copper were affected by the content of ions and reduced copper. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2796–2802, 2006  相似文献   

20.
Non-leaching antibacterial coatings through quaternary ammonium salts containing polymers were successfully produced in a facile way to provide infection resistant surfaces against multi drug resistant bacteria such as B. licheniformis. In order to do so, a series of random copolymers of styrene (S) and vinyl benzyl chloride (VBC) were synthesized by free radical polymerization technique and subsequently, VBC (V) was functionalized with N,N-dimethylhexadecylamine to introduce quaternary ammonium (QA) salts in the backbone of the copolymers. The copolymers showed an excellent film forming ability, thereby providing an ultrathin coating on various substrates such as metal (stainless steel), glass, polyethylene and polystyrene, as observed by SEM.The coatings were found to be uniform, non leachable in aqueous medium and exhibit good adhesion to various substrates. The antibacterial and antibiofilm activity of the non-leachable coating of random copolymers were screened against B. licheniformis. Among, the copolymer containing 75% quaternized VBC (75VSQA) having 16-C long alkyl chain was found to show maximum antibacterial and antibiofilm activity owing to an appropriate hydrophobic /hydrophilic balance. Their non-leachable antibacterial and antibiofim activity make these coatings suitable for many applications, e.g. marine paints, textile/hospital coatings etc.  相似文献   

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