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1.
A novel amine methacrylate monomer trimethylolpropane trimethacrylate–piperazine–ethyleneglycol dimethacrylate (TMPTMA‐PPZ‐EGDMA) was synthesized by amination of trimethylolpropane trimethacrylate (TMPTMA) with excess of piperazine (PPZ) followed by reaction with ethyleneglycol dimethacrylate (EGDMA). Copolymerization of TMPTMA‐PPZ‐EGDMA with 2‐hydroxyethyl methacrylate (HEMA) was carried out by free radical polymerization using ammonium persulfate (APS) and N,N,N′,N′‐tetramethyl ethylenediamine (TEMED) as a redox initiator. The copolymers obtained were then quaternized with 1‐iodooctane. The monomers were characterized by FTIR and 1H NMR spectral studies. The molecular weights and polydispersity values of the monomers were determined with gel permeation chromatography. Quaternized copolymers containing more than 20% amine methacrylate monomer showed microporosity in the range of 9.9–10.4 μm. The antibacterial activity of the quaternized copolymers against Escherichia coli and Staphylococcus aureus was studied using UV–vis spectrophotometer and scanning electron microscopy. Quaternized copolymers showed broad‐spectrum contact‐killing antibacterial properties without releasing any active agent as checked by iodide selective ion meter. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

2.
Poly(ester dimethacrylate) has been synthesized by condensation of the ɛ-caprolactone-based macromonomer and 2-hydroxyethyl methacrylate with dicyclohexylmethane diisocyanate. Network copolymers of different compositions capable of swelling in water, THF, and toluene are obtained by the free-radical copolymerization of poly(ester dimethacrylate) with N-isopropylacrylamide or 2-hydroxyethyl methacrylate. The rate constants and equilibrium swelling indices of network copolymers in these solvents are measured. The amphiphilic properties of the network copolymers can vary in a wide range depending on the composition of copolymers and the nature of a hydrophilic monomer. The copolymers of poly(ester dimethacrylate) with N-isopropylacrylamide are characterized by pronounced thermal sensitivity.  相似文献   

3.
Series of quaternary ammonium tetraphenyl borates salt photobase generators (PBGs) were synthesized using p‐methoxyphenacylmethylene and 2‐naphthoymethylene as chromophores, and triethylene diamine, pyridine or 3‐methyl pyridine as tertiary amine. The kinetics for polymerization of trimethylolpropane triacrylate (TMPTA) monomer using PBGs as free radical photo‐initiator was monitored by differential photo‐calorimeter (DPC). It was found that all the quaternary ammonium tetraphenyl borate salt photobase generators synthesized could initiate free radical polymerization of the acrylate monomer TMPTA by exposure to UV irradiation, but the activity was relatively low. Addition of a small amount of polar solvent to the system could largely increase the polymerization rate and final conversion. Photo‐polymerization was also improved by increasing light intensity or raising reaction temperature. PBGs with p‐methoxyphenacylmethylene as chromophore had higher absorbance at around 280 nm and showed higher activity in initiating photo‐polymerization than those with N‐(2‐naphthoylmethyl) as chromophore. Copyright © 2006 Society of Chemical Industry  相似文献   

4.
Novel surface active maleate and methacrylate monomers based on derivatives of ω‐hydroxy carboxylic acids have been synthesized. The monomers are comprised of hydrophobic alkyl chains and hydrophilic poly(ethylene glycol), quaternary ammonium, sulfonate and carboxylic fragments. Synthesized monomers sufficiently reduce surface tension at the aqueous solution‐air interface. The copolymerization of synthesized monomers with 5‐tert‐butylperoxy‐5‐methyl‐2‐hexene‐3‐yne monomer and N‐vinylpyrrolidone in solvent and emulsion copolymerization of synthesized peroxide containing surface active monomer with styrene have been carried out. The synthesized surface active monomers have been shown to be suitable emulsifiers for obtaining polystyrene colloid dispersions. It has been ascertained that the surface active copolymers obtained can form stable interpolyelectrolyte complexes with oppositely charged polymers.  相似文献   

5.
A series of copolymers PDAMs were synthesized with varying monomer ratio of acrylamide (AM) and N,N‐dimethylaminoethyl methacrylate (DMAEMA). The resulting copolymer solution shows an interesting property of viscosity‐response which is CO2‐triggered and N2‐enabled. Tertiary amine groups of PDAMs experience a reversible transition between hydrophobic and hydrophilic state upon CO2 addition and its removal, which induced different rheological behavior. A combination of zeta‐potential, laser particle‐size analysis, and electrical conductivity analysis indicated that, when the monomer mole ratio of DMAEMA and AM is less than or equal to 3 : 7, the hydrophobic association structure between the copolymer molecules was destroyed by the leading of CO2 and caused a viscosity decrease in its solution. On the contrary, when the monomer mole ratio of DMAEMA and AM is more than 3 : 7, a more extended conformation due to the protonated tertiary amine groups is formed and the enhanced repulsive interactions among the copolymer molecule results in a rise of its solution viscosity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40872.  相似文献   

6.
The absorption, fluorescence excitation and emission spectroscopy, and time‐dependent spectrofluorimetry have been used to study the photophysics of copolymers of N‐vinylcarbazole with different monomers like vinyl acetate, methyl acrylate, methyl methacrylate, butyl acrylate, and butyl methacrylate in dichloromethane. In all the copolymers and at different N‐vinylcarbazole content, the absorption spectra reflect only the monomer carbazole units. The two kinds of excited monomer species of N‐vinylcarbazole are present in S1 state. Short‐lived (~3 ns) excited monomer decays forming low energy excimer obtained by the complete overlap of the excited carbazole monomer. The long‐lived excited monomer (~8 ns) decays to ground state without formation of any excimer. The high energy excimer is relatively short‐lived and is formed by the partial overlap of the carbazole units. The presence of bulky group in the copolymer chain hinders the formation of excimers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 372–380, 2006  相似文献   

7.
A new polymerizable monomer, [4‐(9‐ethyl)carbazolyl]methyl methacrylate ( 2 ), was synthesized by reacting of methacrylic acid and 4‐hydroxymethyl‐9‐ethyl carbazole ( 1 ) by esterification procedure in the presence of N,N′‐dicyclohexylcarbodiimide. The resulting monomer was then polymerized free‐radically to form the poly(methyl methacrylate) containing 4‐(9‐ethyl)carbazolyl pend ent groups. Also, copolymerization of monomer 2 with various acrylic monomers such as methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, and n‐butyl acrylate by azobisisobutyronitrile as a free radical polymerization initiator gave the related copolymers in high yields. The structure of all the resulted compounds was characterized and confirmed by FTIR and 1H NMR spectroscopic techniques. The average molecular weight of the obtained polymers was determined by gel permeation chromatography using tetrahydrofurane as the solvent. The thermal gravimetric analysis and differential scanning calorimeter instruments were used for studying of thermal properties of polymers. It was found that, with the incorporation of bulky 4‐(9‐ethyl)carbazolyl substitutes in side chains of methyl methacrylate polymers, thermal stability and glass transition temperature of polymers are increased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4989–4995, 2006  相似文献   

8.
To modify acrylamide (AAm) hydrogels for specialty applications, it was copolymerized with 2‐Hydroxypropyl methacrylate (HPMA) in different molar ratio at 25°C in 1:1 water–acetone solvent system, using ammonium persulphate (APS) and N,N,N,N‐tetramethyl ethylene diamine (TEMED) initiator–accelerator system. Two series of hydrogels were thus prepared using two different crosslinkers—ethylene glycol dimethacrylate (EGDMA) and N,N‐methylene bisacrylamide (N,N‐MBAAm). To affect property profile of the hydrogels, concentration of HPMA was varied over a range of five concentrations from 3.5 to 28 mM. Hydrogels were further functionalized by partial hydrolysis with NaOH and Hofmann amide degradation reaction. FTIR, Nitrogen analysis, and SEM were used to establish monomer reactivity and structure relationship of the hydrogels. Metal ion uptake was studied as a function of various structural aspects of the hydrogels. Water uptake behavior of the hydrogels was studied at constant time, temperature, and pH, both pre and post metal loading. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3040–3049, 2006  相似文献   

9.
Acrylic copolymer systems consisting of methyl methacrylate and triethylene glycol dimethacrylate with different chemical compositions were synthesized through bulk polymerization using N,N‐dimethyl‐p‐toluidine as an acelerator to obtain nonshrinkable polymers. The use of the tertiary amine on this formulation produces an increase on the volume of the material due to a phase separation in the copolymer, which compensates the volume reduction upon curing. The specific volumes of all materials were determined by volume dilatometry using a dilatometer specially constructed for this purpose. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 586–591, 2000  相似文献   

10.
2,2‐Bis[4‐(2‐hydroxy‐3‐methacryloxypropoxy)phenyl]propane (Bis‐GMA), one of the most important light‐curable dimethacrylate resins, is widely used as dental restorative material. However, one problem of Bis‐GMA is the high water sorption due to the hydrophilic hydroxyl (–OH) group, resulting in a short life in actual application. In this study, to overcome the drawback stated above, novel organic–inorganic dimethacrylate monomer containing polyhedral oligomeric silsesquioxanes (POSS), Bis‐GMA‐graft‐POSS, is synthesized via the nucleophilic addition reaction of isocyanate functionalized POSS (IPOSS) and pendent hydroxyl group of Bis‐GMA. Then the as‐synthesized Bis‐GMA‐graft‐POSS, of which hydroxyl group was substituted by hydrophobic POSS, is also introduced into the Bis‐GMA/TEGDMA matrix to prepare a series of methacrylate‐based hybrids for dental materials under visible light with camphorquinone and ethyl‐4N,N‐dimethy‐laminobenzoae (EDMAB) as initiator and coinitiator, respectively. Compared to Bis‐GMA/TEGDMA composites, water sorption of modified composites can be significantly reduced with the addition of Bis‐GMA‐graft‐POSS. Moreover, the Bis‐GMA/TEGDMA/POSS hybrids show hydrophobic surfaces, leading to much higher water contact angles than that of Bis‐GMA/TEGDMA composites. The morphology of hybrids containing POSS was furthermore studied by X‐ray diffraction (XRD) analysis and X‐ray photoelectron spectroscopy (XPS). The results show that POSS disperses in the matrix in noncrystalline form and tend to migrate to the surface of the modified composites that lead to the lower water sorption and higher water contact angles. These results are very useful for design of novel methacrylate monomers and clinical application. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

11.
Two novel cyclic‐amine monomers, i.e., 3‐allyl‐5,5‐dimethylhydantoin (ADMH) and 7,8‐benzo‐3 allyl‐1,3‐diazasprio[4.5]decane‐2,4‐dione (BADDD) were synthesized with good yields by reacting allyl bromide with 5,5‐dimethylhydantoin (DMH) and 7,8‐benzo‐1,3‐diazasprio[4.5]decane‐2,4‐dione (BDDD), respectively. The synthesized monomers were characterized by FTIR and 1H‐NMR spectra, and copolymerized with acrylonitrile (AN), vinyl acetate (VAC), and methyl methacrylate (MMA) in a small monomer ratio of ADMH and BDDD, respectively. The copolymers were characterized by FTIR, 1H‐NMR, and DSC studies. The N‐halamine derivatives of the corresponding copolymers were found to exhibit high antibacterial activities against Escherichia coli, and the antibacterial properties were durable and regenerable. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2460–2467, 2001  相似文献   

12.
Commercial brominated poly(isobutylene‐co‐isoprene) (BIIR) rubber has been directly used for the initiation of atom transfer radical polymerization (ATRP) by utilizing the allylic bromine atoms on the macromolecular chains of BIIR. The graft copolymerization of methyl methacrylate (MMA) from the backbone of BIIR which was used as a macroinitiator was carried out in xylene at 85 °C with CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as a catalytic complex. The polymerization conditions were optimized by adjusting the catalyst and monomer concentration to reach a higher monomer conversion and meanwhile suppress macroscopic gelation during the polymerization process. This copolymerization followed a first‐order kinetic behavior with respect to the monomer concentration, and the number‐average molecular weight of the grafted poly(methyl methacrylate) (PMMA) increased with reaction time. The resultant BIIR‐graft‐PMMA copolymers showed phase separation morphology as characterized by atomic force microscopy, and the presence of PMMA phase increased the polarity of the BIIR copolymers. This study demonstrated the feasibility of using commercial BIIR polymer directly as a macromolecular initiator for ATRP reactions, which opens more possibilities for BIIR modifications for wider applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43408.  相似文献   

13.
A series of copolymers, poly(acrylamide)‐co‐poly(N,N‐dimethylaminoethyl methacrylate)‐co‐poly(N‐cetyl DMAEMA) (abbreviation PDAMCn), was synthesized with different monomer ratios. The resulting copolymer solution shows pronounced viscosity–response property which is CO2‐triggered and N2‐enabled. Electrical conductivity experiment shows that tertiary amine group on DMAEMA experiences a protonate and deprotonate transition upon CO2 addition and its removal. In addition, different incorporation rates of DMAEMA leads to two kinds of morphological change in the presence of CO2 and thus induces different rheological behaviors. PDAMCn incorporating longer hydrophobic monomer (C18DM) show more pronounced initial viscosity and higher critical stress required to cause network deformation, which consequently enhances the viscosity–response property of the solution. The addition of NaCl could also tune the viscosity of PDAMCn solution. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41468.  相似文献   

14.
Poly{[(N,N‐(dimethylamino)ethyl methacrylate]‐co‐(methyl methacrylate)} copolymers of various compositions were synthesized by reversible addition‐fragmentation chain transfer (RAFT) polymerization at 70 °C in N,N‐dimethylformamide. The polymer molecular weights and molecular weight distributions were obtained from size exclusion chromatography, and they indicated the controlled nature of the RAFT polymerizations; the polydispersity indices are in the range 1.1–1.3. The reactivity ratios of N,N‐(dimethylamino)ethyl methacrylate (DMAEMA) and methyl methacrylate (MMA) (rDMAEMA = 0.925 and rMMA = 0.854) were computed by the extended Kelen–Tüdös method at high conversions, using compositions obtained from 1H NMR. The pH‐ and temperature‐sensitive behaviour were studied in aqueous solution to confirm dual responsiveness of these copolymers. The thermal properties of the copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. The kinetics of thermal degradation were determined by Friedmann and Chang techniques to evaluate various parameters such as the activation energy, the order and the frequency factor. © 2012 Society of Chemical Industry  相似文献   

15.
Homopolymer and copolymers containing metronidazole (MTZ) drug were synthesized. Acryloyl chloride was reacted with MTZ (drug) to produce monomer containing MTZ, and then the monomer was copolymerized with various amounts of methyl methacrylate. The produced monomer, homopolymer, and copolymers were characterized by elemental analysis, IR, and 1H‐NMR. The antimicrobial activities of the synthesized polymers were tested against Kelpsilic as fungal organisms, and Escherichia coli, Bacillus subitilus, and Pesudomonus areuginosa as bacteria organisms. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

16.
2‐Hydroxyethyl methacrylate (HEMA) based polymeric hydrogels were synthesized by free‐radical redox bulk polymerization technique using 1% ethyleneglycol dimethacrylate (EGDMA) as crosslinking monomer and ammonium persulfate (APS) and N,N,N′,N′‐tetramethyl ethylenediamine (TEMED) as redox initiator. Polymeric hydrogel samples were loaded with solid elemental iodine. Thermal and physical characteristics of polymer before loading and after 3 months release of iodine were evaluated by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). On immersing in water, different forms of iodine were released from the hydrogel device. The amount and rate of release of I? and I were measured by analytical techniques. Released iodine species showed broad spectrum antimicrobial properties and release was sustained for about 120 days. Polymeric hydrogel iodine‐based system developed can be used as a device for controlled release of iodine species at concentration levels sufficient for disinfection to get potable water. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3334–3340, 2007  相似文献   

17.
Bifunctional aminoalkyldimethylpropylammonium salts (N‐(3‐aminopropyl)‐N,N‐dimethylpentylammonium chloride, N‐(3‐aminopropyl)‐N,N‐dimethyloctylammonium chloride, N‐(3‐aminopropyl)‐N,N‐dimethyldecylammonium chloride, N‐(3‐aminopropyl)‐N,N‐dimethyldodecylammonium chloride) are synthesized and their structure‐dependent antibacterial effect against Gram‐negative Escherichia coli and Gram‐positive Lactococcus lactis is investigated. To this end, resins prepared from bisphenol A diglycidyl ether (2,2‐bis[4‐(glycidyloxy)phenyl]propane) and diethylenetriamine (2,2′‐diaminodiethylamine) as matrix and the bifunctional aminoalkyldimethylpropylammonium salts in a ratio of 6 mol% compared to epoxy components are used. A dependence of antibacterial effect on alkyl chain length of the quaternary ammonium compounds is observed for both species. Furthermore, resins with N‐(3‐aminopropyl)‐N,N‐dimethyldecylammonium chloride in varying concentrations up to 16 mol% for both organisms show a concentration‐dependent antibacterial effect of the quaternary ammonium salt. The antibacterial materials are characterized by differential scanning calorimetry, infrared spectroscopy and rheological studies. © 2013 Society of Chemical Industry  相似文献   

18.
Poly(methyl methacrylate)‐block‐polyurethane‐block‐poly(methyl methacrylate) tri‐block copolymers have been synthesized successfully through atom transfer radical polymerization of methyl methacrylate using telechelic bromo‐terminated polyurethane/CuBr/N,N,N,N″,N″‐pentamethyldiethylenetriamine initiating system. As the time increases, the number‐average molecular weight increases linearly from 6400 to 37,000. This shows that the poly methyl methacrylate blocks were attached to polyurethane block. As the polymerization time increases, both conversion and molecular weight increased and the molecular weight increases linearly with increasing conversion. These results indicate that the formation of the tri‐block copolymers was through atom transfer radical polymerization mechanism. Proton nuclear magnetic resonance spectral results of the triblock copolymers show that the molar ratio between polyurethane and poly (methyl methacrylate) blocks is in the range of 1 : 16.3 to 1 : 449.4. Differential scanning calorimetry results show Tg of the soft segment at ?35°C and Tg of the hard segment at 75°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

19.
Copolymers of 2,4‐dichlorophenyl methacrylate and hydrophilic monomer (N‐vinylpyrrolidone) were synthesized with different feed ratios using dimethylformamide as solvent and 2,2′‐azobisisobutyronitrile as initiator at 70 °C. The copolymers were characterized by IR spectrometry. Copolymer compositions were determined by UV spectrometry. The monomer reactivity ratios were determined by applying the conventional linearization method of Fineman‐Ross. Gel permeation chromatography was employed for determining molecular weights and polydispersity indexes. Thermogravimetric analyses of polymers were carried out in nitrogen atmosphere. Homo‐ and copolymers were tested for their antimicrobial properties against selected microorganisms. © 2003 Society of Chemical Industry  相似文献   

20.
The efficiency of 4,4′‐bis(N,N‐diethylamino)benzophenone (DEABP) for the polymerization of dimethacrylate monomers in thick sections ( 1 – 2 mm) was studied. DEABP (λmax = 365 nm) represents a complete initiating system as it contains both ketone and amine functional groups. During irradiation, DEABP photobleaches at a fast rate causing deeper penetration of light through the underlying layers, but the photoinitiation efficiency (rate of polymerization per photon absorption rate) is relatively poor. As a result, irradiation of methacrylate monomers at 365 nm results in a slow average polymerization rate and a reduced monomer conversion for thick sections due to the light attenuation caused by the high absorptivity of DEABP and photolysis products. These results highlight the inherent interlinking of light attenuation and photobleaching rate in polymerization of thick sections. Copyright © 2011 Society of Chemical Industry  相似文献   

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