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1.
Poly[(maleic anhydride)‐co‐(vinyl acetate)] (MAVA) copolymer was synthesized by free radical polymerization reaction, in methyl ethyl ketone at 80 °C, using benzoyl peroxide as the initiator. The copolymer was then modified with a biomolecule, noradrenaline (NA). The modification reaction was performed at 70 °C in dimethylformamide containing triethylamine as the catalyst. The modified polymer was named MAVA/NA. Structural characterization of the copolymer and the modified product was carried out by Fourier transform infrared (FTIR) and 1H NMR and 13C NMR spectroscopy. The FTIR, 1H NMR and 13C NMR spectra confirmed that NA was successfully covalently bound to the MAVA copolymer backbone. Surface morphology was visualized by atomic force microscopy. The cumulative release of NA from MAVA/NA was determined in phosphate buffered saline solution for 7 days at 37 °C and compared with MAVA. Cytotoxicity of the MAVA/NA was evaluated by using a mouse fibroblast cell line (L929). Results obtained indicated that MAVA/NA had almost no toxicity and no negative effect on cell viability at 250 µg mL?1 concentration. © 2012 Society of Chemical Industry  相似文献   

2.
Calcium diacrylate (CDA) and calcium dimethacrylate (CDM) divinyl monomers were synthesized by a solvo thermal method. The FTIR spectra showed a peak at 1650 cm?1 due to the presence of a C?C for both CDA and CDM. Proton NMR and carbon NMR confirmed the structure of CDA and CDM synthesized by a solvo thermal method. DSC determined the melting temperatures of CDA and CDM. XRD indicated the presence of a d110 plane peak for CDA and CDM. The % weight residue that remained above 700°C in TGA method confirmed the higher thermal stability of CDA. Thus, synthesized CDA and CDM were surface grafted on linear low density poly(ethylene) (LLDPE) at 160°C under inert atmosphere by thermolysis method. FTIR confirmed the presence of C?O stretching due to CDA and CDM in LLDPE backbone after thermolysis reaction. 1H‐NMR confirmed the chemical grafting of CDM onto LLDPE. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

3.
Three maleic anhydride copolymers were synthesized by free-radical copolymerization. The synthesized products were named as follows: maleic anhydride–styrene (MAST); maleic anhydride–vinyl acetate (MAVA), and maleic anhydride–methyl methacrylate (MAMMA). Initiators used in the reactions were azobisisobutyronitrile (AIBN, 70 °C, benzene) for MAST and benzoyl-peroxide [BPO, 80 °C, methyl ethyl ketone (MEK)] for MAVA and MAMMA. Structural characterizations were carried out by Fourier transform infrared (FTIR) and nuclear magnetic resonance [1H NMR, 13C NMR, and 13C-APT (attached-proton test)] spectrometry. Surface morphology was studied by scanning electron microscopy (SEM). Solubility of the copolymers was examined in water and in twelve different organic solvents. Cytotoxicity of the copolymers and the solvents was evaluated by using a mouse fibroblast cell line (L929), copolymers had almost no toxicity. Of the twelve organic solvents, acetone, MEK, and tetrahydrofuran (THF) produced the least toxicity. MEK was found to be the best solvent and used for the solvation of the copolymers.  相似文献   

4.
Copolymers of poly(acrylonitrile‐co‐ethyl methacrylate), P(AN‐EMA), with three different EMA content and parent homopolymers were synthesized by emulsion polymerization. The chemical composition of copolymers were identified by FTIR, 1H‐NMR and 13C‐NMR spectroscopy. The thermal properties of copolymers were modified by changing the EMA content in copolymer compositions. Various amounts of LiClO4 salt loaded (PAN‐co‐PEMA) copolymer films were prepared by solution casting. The dielectric properties of these films at different temperatures and frequencies were investigated. It was found that the dielectric constant and ac‐conductivity of copolymer films were strongly influenced by the salt amounts and EMA content in copolymers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

5.
Summary Chelating networks based on modified chemically acrylonitrile with hydrazine at alkaline solution were synthesized. The resin beads with different porosities were obtained by aqueous suspension copolymerization of acrylonitrile (AN) and divinylbenzene (DVB). The unmodified and modified resins were characterized by bulk density, surface area, average pore diameter, elemental analysis (CHN), FTIR, 13C CP/MAS NMR and scanning electronic microscopy. Elemental analyses were used to observe the increasing of nitrogen and oxygen contents due to chemical modification. Spectroscopic techniques (FTIR and 13C CP/MAS NMR) were employed to study the structural changes provoked by the modification with hydrazine. The contents of carboxyl and amidrazone group into the copolymer structure were dependent on the reaction conditions.  相似文献   

6.
A modified starch tannage was synthesized by radical copolymerization of degraded starch and resorcinol (RC) using horseradish peroxidase (HRP)/H2O2 as an initiator. The effects of the degradation degree, system pH value, reaction temperature on the copolymerization, and tanning properties of the graft copolymer used in leather processing were investigated. The application results showed that the graft copolymer has excellent tanning properties. The shrinkage temperature (Ts) of the tanned leather reached 85.4°C, and the thickness increment ratio of the retanned leather was 23.1%. The tanning effects were significantly improved with RC modification compared with the graft copolymer of starch and vinyl monomers. The results indicated that the graft copolymer of starch and RC may be a replacement for toxic chrome and aldehyde tannage. The structure of the graft copolymer was characterized by FTIR, 1H-NMR, GPC, and UV. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

7.
Biodegradable copolymers of 2‐methylene‐1,3‐dioxepane (MDO) and styrene (ST) were synthesized by free‐radical copolymerization using di‐t‐butyl peroxide (DTBP) as the initiator. The copolymers containing ester units were characterized by Fourier transform infrared (FTIR), 1H‐NMR, and 13C‐NMR spectroscopy. Their molecular weight and polydispersity index were determined by gel permeation chromatography (GPC). In vitro enzymatic degradation of poly(MDO‐co‐ST) was performed at 37°C in phosphate buffer solution (PBS, pH = 7.4) in the presence of Pseudomonas lipase or crude enzyme extracted from earthworm. The experiment showed that incorporating ester units into C? C backbone chain of polystyrene would result in a biodegradable copolymer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1146–1151, 2007  相似文献   

8.
Polyesteramide (PEA) coating resin, synthesized from linseed oil, a sustainable resource, was found to show improved physicomechanical and acid‐resistance properties. To further improve these properties in terms of alkali resistance, scratch hardness, and thermal stability and to reduce the baking temperature, we have attempted to incorporate styrene into the polymer backbone through its copolymer with maleic anhydride. The structural elucidation of modified PEA resin (SCPEA) was carried out by FTIR, 1H‐NMR, and 13C‐NMR spectroscopes. The physicomechanical and chemical‐resistance properties were investigated by standard methods and thermal stability was investigated by thermogravimetric analysis method. A comparative study of these properties of PEA and SCPEA was carried out. It was observed that the SCPEA showed better properties than the reported one. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2538–2544, 2004  相似文献   

9.
Free‐radical polymerization of p‐cumyl phenyl methacrylate (CPMA) was performed in benzene using bezoyl peroxide as an initiator at 80°C. The effect of time on the molecular weight was studied. Functional copolymers of CPMA and glycidyl methacrylate (GMA) with different feed ratios were synthesized by free‐radical polymerization in methyl ethyl ketone at 70°C, and they were characterized by FTIR and 1H‐NMR spectroscopy. The molecular weights and polydispersity indexes of the polymers and copolymers were determined by gel permeation chromatography. The copolymer composition was determined by 1H‐NMR. The glass‐transition temperature of the polymer and the copolymers was determined by differential scanning calorimetry. The reactivity ratios of the monomers were determined by the Fineman–Ross and Kelen–Tudos methods. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 336–347, 2005  相似文献   

10.
In this article, the synthesis and characterization of the new unsaturated epoxyoligoester suitable for further modification have been presented. The new unsaturated epoxyoligoester was prepared by the chemical modification of the structure of the unsaturated oligoester obtained in polycondensation process of cyclohex‐4‐ene‐1,2‐dicarboxylic anhydride, maleic anhydride, and ethylene glycol. The chemical modification of the structure of initial oligoester by 38–40% peracetic acid in mild conditions allowed to introduce the oxirane groups into the oligoester backbone. The structure of the samples before and after epoxidation was characterized by FTIR, 1H NMR, DSC, and elemental analyses. The FTIR and 1H NMR analyses confirmed that the oxidation reaction took place through the double bonds in cyclohexenyl rings, whereas the double bonds in the unsaturated chain remained unaltered. Moreover, the epoxidation reaction was performed at 20 and 40°C for 1–6 h to define the optimum temperature and time conditions of this process. The optimum temperature and time conditions were 40°C and 2.5 h, respectively. In this conditions, the maximum conversion of the double bonds (98.3%) and minimal epoxide degradation were observed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

11.
Anirban Sen Gupta 《Polymer》2004,45(14):4653-4662
Starting from the natural amino-acid l-tyrosine, a diphenolic monomeric molecule was developed using carbodiimide mediated solid-phase synthesis techniques. This monomeric molecule was polymerized by reacting it in equimolar proportions with suitable dihalophosphates to yield novel biodegradable polyphosphates containing peptide linkages and phosphoester linkages alternating in the polymer backbone. The biodegradability of such a polymer is expected to arise from the hydrolytic degradability of the phosphoester linkages and the enzymatic degradability of the peptide linkages in the polymer backbone. Design of such a polymer is expected to make a significant contribution to biomaterials research, regarding drug delivery device and tissue engineering scaffold applications. The monomer was obtained by a novel solid phase carbodiimide-mediated amide coupling process. The subsequent polymers were obtained by solution-phase dehydrochlorination polycondensation reactions in the presence of a suitable acid acceptor. The synthesized polymers were characterized by 13C NMR, 31P NMR and FTIR for their chemical structure, by GPC for their molecular weight distribution, and by DSC and TGA for their thermal transition characteristics.  相似文献   

12.
High refractive index polymer films have been extensively investigated because of their wide application potentials. We now designed thiophene‐containing polystyrene as colorless and transparent high‐refractive‐index thin film. The copolystyrenes were synthesized by general radical polymerization with controlled mole ratios 0 : 10, 1 : 9, 3 : 7, 5 : 5, 7 : 3, 9 : 1, 10 : 0 (styrene : p‐bromostyrene), respectively. Next, the thiophene‐containing polystyrenes were synthesized by Suzuki‐Miyaura coupling reaction. The chemical structures of synthesized thiophene‐containing polystyrene in accordance with ratios were confirmed by using 1H‐NMR, 13C‐NMR, and FTIR. The effect of the thiophene units on refractive index according to copolymer ratios were confirmed by using prism coupler. The thiophene‐containing polystyrene showed improved refractive index ranging from 1.58 to 1.67 and birefringence in the range of 0.0001–0.0019. The thermal stability and thermal behaviors of thiophene‐containing polystyrene also can be confirmed by TGA and DSC. The polymers have high glass transition temperature in the range of 108°C–177°C. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

13.
Glycidyl methacrylate (GMA) was grafted onto natural rubber (NR) using emulsion polymerization method. The structures of copolymers were characterized by 1H nuclear magnetic resonance (1H‐NMR), solid state 13C‐NMR spectroscopy, and Fourier transform infrared spectrometer (FTIR). The %grafting obtained from the gravimetric method and the absorbance ratio were compared. Effects of reaction temperature, GMA content, and reaction time on %grafting, grafting efficiency, and %conversion of GMA monomer were determined. Effect of %grafting on mechanical properties of the graft copolymer was studied. Experimental result showed that the appropriate reaction time was 8 h at a reaction temperature of 30°C. Moreover, tensile strength and modulus of the graft copolymer increased with increasing %grafting. However, elongation at break of the graft copolymer decreased with increasing %grafting. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 3152–3159, 2011  相似文献   

14.
Graft copolymers of carboxymethyl guar gum (CMGG) and polyacrylamide (PAM) have been synthesized by grafting polyacrylamide chains onto carboxymethyl guar gum backbone using a ceric‐ion‐induced solution polymerization technique. By varying the amount of initiator, three different grades of graft copolymers are synthesized. The characterization of graft copolymer is carried out by FTIR, NMR, intrinsic viscosity measurement, SEM, SLS, DTG, and rheology. A comparison of flocculation efficiency of CMGG and its graft copolymer shows that the graft copolymer exhibits better flocculation performance. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

15.
A new class of copoly(ether-carbonate)s was synthesized using a melt polycondensation reaction of the bis(hydroxyethyl ether) of bisphenol A with bisphenols and diphenyl carbonate. Copolymers with a wide range of Tg values (62–140°C) were obtained. The copolymer structures were established by 1H NMR, 13C NMR and FTIR investigations. © 1998 Society of Chemical Industry  相似文献   

16.
Water-soluble maleic anhydride-containing poly[maleic anhydride-alt-acrylic acid] (poly(MA-alt-AA) or MAAA) copolymer was synthesized by free-radical chain polymerization reaction, in 1,4-dioxane in the presence of benzoyl peroxide, 0.1 %, as the radical initiator at 70 °C under a nitrogen atmosphere. The purified copolymer was then modified with an anti-external fungal and anti-cancer active agent, acriflavine (AF). The modification reaction was performed 48 h at 70 °C in dimethylformamide organic media, using triethylamine (TEA or Et3N) as the catalyst. The modified or conjugated copolymer/drug couple was named as MAAA/AF. Detailed structural characterization of the copolymer (MAAA) and modified product (MAAA/AF) was carried out by Fourier Transform Infrared (FTIR) and Nuclear Magnetic Resonance (1H-NMR and 13C-NMR). The obtained FTIR, 1H-NMR, and 13C-NMR spectra confirmed that AF was successfully bound to the MAAA copolymer backbone by ring-opening reaction. Antimicrobial susceptibility of the MAAA, AF, and MAAA/AF was evaluated by Kirby Bauer Disc Diffusion method on Mueller–Hinton Agar using Enterecoccus faecium, Enterohaemorrhagic Escherichia coli (EHEC), Staphylococcus aureus and Listeria monocytogenes. Results obtained indicated that MAAA/AF had antibacterial activity on EHEC and S. aureus at 50, 40, and 30 µg. A mechanism for MAAA and AF was then also suggested for the conjugation reaction.  相似文献   

17.
This work describes the synthesis and characterization of a new series of semifluorinated sulfonated polytriazole copolymers (PTATSH‐XX) with varying degree of sulfonation and higher IEC. The copolymers have been prepared by click reaction using a combination of diazide monomers; a newly synthesized diazide monomer namely 4,4‐bis[3‐trifluoromethyl‐4(4‐azidophenoxy)phenyl]benzene (TAZ) and a commercially available diazide monomer namely 4,4′‐diazido‐2,2′‐stilbenedisulfonic acid disodium salt (DADSDB) with a bis‐alkyne monomer namely 4,4′‐(propane‐2,2‐diyl)bis((prop‐2‐ynyloxy)benzene) (BPEBPA). The copolymers are well characterized by FTIR and NMR spectroscopy and have exhibited good solubility and film forming abilities along with good thermal and chemical stability, low water uptake, good dimensional stability and high mechanical properties. The TEM micrographs of the copolymer membranes show good phase separated morphology with cluster size in the range 10–60 nm. The proton conductivity values of the copolymer membranes are found in the range of 15–90 mS cm?1 at 80°C and 16–97 mS cm?1 at 90°C. POLYM. ENG. SCI., 57:312–323, 2017. © 2016 Society of Plastics Engineers  相似文献   

18.
A methoxy poly(ethylene oxide) (MPEO) grafted poly(acrylic acid) (PAA) comblike copolymer was synthesized by the direct condensation of MPEO onto the PAA backbone in the presence of dicyclohexyl dimethylcarbodiimide (DCC) and 4‐dimethylaminopyridine (DMAP). Its chemical structure was characterized by Fourier transform infrared and 1H‐NMR spectroscopies. The effects of different catalysts, solvents, reaction temperatures, and reaction times on the grafting degree of the PAA‐g‐MPEO comblike copolymer were investigated. Compared to p‐toluene sulfonic acid, DMAP/DCC as a catalyst markedly increased the grafting degree. The optimum reaction conditions were a tetrahydrofuran/water mixture solvent, a reaction temperature of 50°C, and a reaction time of 168 h. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

19.
In this study, a novel pH–temperature‐responsive copolymer was first synthesized by the radical copolymerization between HPA (2‐hydroxypropyl acrylate and 2‐hydroxyisopropyl acrylate) and AMHS (aminoethyl methacrylate hydrochloric salt). The molecular structure of the corresponding copolymer has been confirmed by 1H‐NMR and FTIR. The lower critical solution temperature of the resulting copolymer exhibited a considerable dependence upon the ratio of monomers and pH value in the medium. On the basis of the copolymer, a hydrogel as drug release carrier was prepared via the introduction of a crosslinker, N,N′‐methylenebisacrylamide. The swelling behaviors of hydrogel in the different pH value, temperature, and NaCl concentration have indicated that the hydrogel showed a remarkable phase transition at 31.5°C. The swelling ratio was increased with an increasing of pH value, especially in the greater pH values. By the use of caffeine as a model drug, we investigated the caffeine‐controlled release from hydrogel systematically as a function of pH value, temperature, and crosslinker content. The caffeine release was sensitive to the temperature. Only 55% caffeine was released from the hydrogel at room temperature, whereas ~ 92% caffeine diffused into the medium at 37°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

20.
A kind of fluorosilicone monomer with polymerizable vinyl group and fluorine and silicon components has been designed and synthesized. A series of acrylic copolymers were prepared using the monomer and normal acrylic monomers. The effects of the monomer on the surface properties and thermostability of the copolymers were studied. The chemical structure of the monomer and the copolymers were confirmed by FTIR, 1H NMR, and 19F NMR. MALDI‐TOF‐MS was used to monitor the molecular weight variation during the monomer synthesis process. Thermal properties of the copolymers were analyzed by DSC and TGA. Surface properties of the copolymer films were characterized by static water contact angles, AFM, and XPS. Results showed that the fluorosilicone monomer with the expected structure was synthesized and had been copolymerized into the copolymers. The monomer contributed to a uniform hydrophobic film with no influence on the surface roughness. The thermostability of the copolymers was improved by the monomer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41926.  相似文献   

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