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1.
A novel quaternary amine methacrylate monomer (QAMA) was synthesized by amination of dimethacrylate with piperazine followed by its quaternization using an alkyl iodide. Copolymerization of QAMA with 2‐hydroxyethyl methacrylate was carried out by free radical bulk polymerization technique at room temperature using ammonium persulfate and N,N,N′,N′‐tetramethyl ethylenediamine as a redox initiator. The monomer as well as copolymers was characterized by FTIR and 1H NMR spectral studies. Thermal and physical characteristics of copolymers of varying compositions of QAMA were evaluated by thermogravimetric analysis, differential calorimetry, contact angle and scanning electron microscopy. The antibacterial activity of the synthesized quaternary amine dimethacrylate copolymers against Escherichia coli and Staphylococcus aureus was studied by zone of inhibition and colony count method. QAMA copolymers showed broad‐spectrum contact killing antibacterial properties without releasing any active agent as checked by iodide‐selective ion meter. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1038–1044, 2006  相似文献   

2.
Ionic networked polymers containing ionic liquids were synthesized by radical copolymerization of 1-(2-methacryloyl)ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (Met-IL) and difunctional or trifunctional methacrylate cross-linkers, ethylene glycol dimethacrylate (EGDMA), or trimethylolpropane trimethacrylate (TMPTMA) in the presence of an ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMImTFSI). For comparison, nonionic networked polymers containing the ionic liquid were prepared by radical copolymerization of methyl methacrylate (MMA) with EGDMA in the presence of EMImTFSI. Met-IL/EGDMA/EMImTFSI(50) showed higher ion conductivity and ionic liquid holding ability than the corresponding MMA/EGDMA/EMImTFSI(50), while Met-IL/TMPTMA/EMImTFSI(50) showed lower ionic conductivity with higher holding ability than MMA/EGDMA/EMImTFSI(50).  相似文献   

3.
Ionic networked polymers containing ionic liquids were synthesized by radical copolymerization of 1-(2-methacryloyl)ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (Met-IL) and difunctional or trifunctional methacrylate cross-linkers, ethylene glycol dimethacrylate (EGDMA), or trimethylolpropane trimethacrylate (TMPTMA) in the presence of an ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMImTFSI). For comparison, nonionic networked polymers containing the ionic liquid were prepared by radical copolymerization of methyl methacrylate (MMA) with EGDMA in the presence of EMImTFSI. Met-IL/EGDMA/EMImTFSI(50) showed higher ion conductivity and ionic liquid holding ability than the corresponding MMA/EGDMA/EMImTFSI(50), while Met-IL/TMPTMA/EMImTFSI(50) showed lower ionic conductivity with higher holding ability than MMA/EGDMA/EMImTFSI(50).  相似文献   

4.
The aim of this study was to evaluate the effect of the association between bisphenol‐A diglycidyl dimethacrylate (BisGMA) or its ethoxylated version (BisEMA) with diluents derived from the ethylene glycol dimethacrylate (EGDMA), with increasing number of ethylene glycol units (1: EGDMA, 2: DEGDMA, 3: TEGDMA, or 4: TETGDMA), or trimethylol propane trimethacrylate (TMPTMA) or 1,10‐decanediol dimethacrylate (D3MA) on polymerization stress, volumetric shrinkage, degree of conversion, maximum rate of polymerization (Rpmax), and elastic modulus of experimental composites. BisGMA containing formulations presented lower shrinkage and stress but higher modulus and Rpmax than those containing BisEMA. TMPTMA presented the lowest stress among all diluents, as a result of lower conversion. EGDMA, DEGDMA, TEGDMA, and TETGDMA presented similar polymerization stress which was higher than the stress presented by D3MA and TMPTMA. D3MA presented similar conversion when copolymerized with both base monomers. The other diluents presented higher conversion when associated with BisEMA. EGDMA showed similar shrinkage compared with DEGDMA and higher than the other diluents. The lower conversion achieved by TMPTMA did not jeopardize its elastic modulus, similar to the other diluents. Despite the similar conversion presented by D3MA in comparison with EGDMA and DEGDMA, its lower elastic modulus may limit its use. Rather than proposing new materials, this study provides a systematic evaluation of off the shelf monomers and their effects on stress development, as highlighted by the analysis of conversion, shrinkage and modulus, to aid the optimization of commercially available materials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

5.
Coagents are vinyl monomers that react with free radicals formed by peroxide dissociation and are either grafted to elastomer chains or homopolymerized within a segregated phase to form a crosslinked network. The initial phase distribution within the elastomer matrix is of great importance for the final user properties of a composite material. In this study, the morphology of blends of each of three different coagents, that is, zinc dimethacrylate (ZDMA), N,N′‐m‐phenylene dimaleimide (HVA‐2), and trimethylolpropane trimethacrylate (TMPTMA) on a reinforcing substrate with dicumyl peroxide and hydrogenated acrylonitrile butadiene elastomer after processing was investigated with scanning electron microscopy. The morphology that evolved during processing was then compared to the results obtained from dynamic mechanical analysis (DMA) of the blends. Dynamic mechanical properties were modeled with a continuous relaxation distribution function, the Williams–Landel–Ferry equation, and the modified Guth–Gold equation. In the case of ZDMA and TMPTMA, a microphase and a nanophase evolved during processing, whereas the HVA‐2 phase in the blends remained well segregated. The volume fraction of the particles under 100 nm in ZDMA and TMPTMA blends ranged from 79 to 89%. The DMA results revealed the reinforcing effect of ZDMA and TMPTMA during the glass‐transition and in the plateau region, whereas HVA‐2 exhibited plasticizer‐like behavior. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

6.
The aim of this study was to prepare transparent polystyrene (PSt) hybrid materials containing silicone macromonomer. Silicone urethane methacrylate (SiUMA) was synthesized by the reaction between the hydroxyl end groups of a silicone macromonomer and the isocyanate group of 2‐methacryloyloxyethyl isocyanate (MOI), and copolymers with different weight proportions were prepared by copolymerization of styrene (St), SiUMA and ethyleneglycol dimethacrylate (EGDMA). Though the prepared P(St‐co‐SiUMA) copolymers which had not introduced EGDMA were opaque, the prepared P(St‐co‐SiUMA‐co‐EGDMA) copolymers were transparent, similarly to pure PSt. DSC and 1H‐NMR measurements were carried out to investigate the factors in this transparency in detail. From these measurement results, it was confirmed that the reactivity of the copolymerization had a significant influence on the transparency of the product. In addition, the contact angle of P(St‐co‐SiUMA‐co‐EGDMA) with 10 wt % SiUMA was greater than 90°, which was a 10° improvement compared to pure PSt. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

7.
Poly(N-vinyl pyrrolidone-co-n-butyl methacrylate) P(NVP-co-nBMA) copolymers containing high N-vinyl pyrrolidone content were crosslinked to increase their hydro-stable nature for controlled drug delivery. Diethylene glycol dimethacrylate (DEGDMA) and trimethylolpropane trimethacrylate (TMPTMA) were used as crosslinkers. The effect of crosslinker concentration and functionality on gel content, thermal stability and water uptake at 37 °C was investigated. The gel contents and thermal stability increased while water uptake decreased with increasing concentration and functionality of crosslinker. The copolymer crosslinked by TMPTMA showed good mechanical properties. The porous network structure of the copolymers was confirmed by scanning electron microscopic studies. Dexamethasone was selected as a model drug and its controlled release was observed for 22 days from TMPTMA crosslinked copolymer (NB91-T2) film, whereas 96 % drug was released in 35 days for DEGDMA crosslinked copolymer (NB91-D2) film. The kinetics of 10 h drug release identified first-order drug release for NB91-D2 and Higuchi kinetics for NB91-T2. The initial 60 % drug release followed non-Fickian diffusion mechanism. These results indicate the future application of NB91-D2 and NB91-T2 copolymer films as a drug carrier for implant coatings.  相似文献   

8.
Films obtained from copolymer latexes of n‐butyl methacrylate (BMA) with a series of crosslinking monomers [i.e., a macromonomer crosslinker (Mac), ethylene glycol dimethacrylate (EGDMA), and aliphatic urethane acrylate] exhibited differences in their tensile properties and swelling behaviors. For P(BMA‐co‐EGDMA) copolymer, a dependence on the initiator type was obtained. It is postulated that the network microstructures for the various copolymers evolved as the result of the copolymerization reactions between the monomer pairs during the synthesis in the miniemulsion free‐radical copolymerization. These network microstructures are, therefore, hypothesized to influence the mechanical properties of the resultant films. Copolymers prepared with Mac were tough in comparison with copolymers made with EGDMA. The presence of longer linear or lightly crosslinked poly(n‐butyl methacrylate) (PBMA) chains and the looseness of the crosslinked network structures in the PBMA‐co‐Mac copolymers appear to be the factors responsible for the differences. All of the copolymer films disintegrated into swollen individual microgels when they were immersed in tetrahydrofuran. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 42–49, 2003  相似文献   

9.
A series of macroporous beaded terpolymers with epoxy groups were synthesized by suspension polymerization with glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA), and the third monomers including styrene, methyl methacrylate, n‐butyl acrylate (BA), butyl methacrylate (BMA), and 2‐hydroxyethyl methacrylate for immobilization of Candida lipolytica lipase. The effect of various third monomers on loading and activity recovery of immobilized lipase were studied. Terpolymers with BA as the third monomer were found to give the biggest loading of lipase, and the activity recovery of lipase immobilized on poly(GMA‐EGDMA‐BA) terpolymers reached 79.0%. As the content of BA (%) increasing, the loading of lipase enhanced, but the activity recovery reached 88.5% for the initial stage and decreased to 46.9% at last. The poly(GMA‐EGDMA‐BA‐10) showed an optimal result in lipase immobilization. Lipase immobilized on poly(GMA‐EGDMA‐BA‐10) carriers had broader pH and higher temperature stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

10.
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   

11.
Polyfunctional monomers (PFMs), namely, trimethylol propane trimethacrylate (TMPTMA), trimethylol propane triacrylate, ethylene glycol dimethacrylate, and diethylene glycol diacrylate were blended with low‐density polyethylene (LDPE) and exposed to different doses of EB irradiation. Fourier transform infrared and ultraviolet and UV–vis spectroscopy of the unirradiated, irradiated, unloaded, and PFMs‐loaded LDPE films were studied under various irradiation doses up to 300 kGy. The degree of crosslinking and oxidative degradation, as measured by the spectroscopic parameters, were dependent on both the irradiation dose and the type of loaded PFMs. For all of the loaded monomers, the extent of crosslinking increased at different rates as a function of irradiation dose. TMPTMA monomer was the most efficient in enhancing the crosslinking of LDPE films compared to the other loaded monomers. However, the unloaded LDPE film showed the least extent of crosslinking. In addition, the EB‐radiation‐induced changes, such as trans‐vinylene formation, a decrease in vinyl and vinylidene unsaturation; and carbonyl double‐bond formation and change in crystallinity were correlated. The importance of these results on the prediction of the role of polyfunctional monomers in the production of crosslinked polymers is discussed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2025–2035, 2003  相似文献   

12.
Herein, we report the synthesis of poly(4‐vinylphenylboronic acid) (PVPBA) and poly[2‐(dimethylamino)ethyl methacrylate] (PDMAEMA) homopolymers, copolymers, and their methyl, pentyl, and octyl quaternized forms as dopant in water‐based permanent antibacterial paints. Both quaternized and nonquaternized forms of P(VPBA‐co‐DMAEMA) copolymers have reflected higher MIC values relative to PDMAEMA homopolymers. High molecular weight copolymers were more active against Escherichia coli ATCC 25922, contrarily, lower molecular weight copolymers showed higher antibacterial activity against Staphylococcus aureus ATCC 25923. The paint films prepared with quaternized PDMAEMA homopolymers with a weight of 10% showed better antibacterial activity in water and airborne tests than the copolymers. However, it has been shown that the inadequate anti‐biofilm properties of homopolymer‐containing paint films are overcome with the VPBA content of the copolymer structure and the most effective antibacterial and anti‐biofilm properties have been obtained with paint films containing P(VPBA‐co‐5QDMAEMA) copolymers. These paint films, which can maintain antibacterial and anti‐biofilm properties for at least 1 year, have the potential to be an alternative to Ag/Cl based solid surfaces which require the active substance to be regenerated. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46245.  相似文献   

13.
Miniemulsion copolymerization of n‐butyl methacrylate and crosslinking monomers such as a macromonomer crosslinker (Mac), ethylene glycol dimethacrylate (EGDMA), or an aliphatic urethane acrylate macromonomer (AUA) was utilized to obtain crosslinked latex particles. The crosslinking monomers were added at 0.2 mol %, on the basis of the amount of n‐butyl methacrylate utilized in a polymerization. The development of the gel content during the copolymerization reaction differs depending on the type of the crosslinking monomer. In addition to the crosslinking reactions between the n‐butyl methacrylate and the crosslinking monomers, other kinetic events, such as microphase separation, may have occurred, giving rise to different particle morphologies, dependent on the type of initiator used (i.e., oil‐soluble or water‐soluble). © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1721–1730, 2001  相似文献   

14.
A crosslinking system consisting of 1,1‐di‐t‐butylperoxy‐3,3,5‐trimethyl cyclohexane peroxide and trimethylolpropane trimethacrylate (TMPTMA) has been used to introduce crosslinks into unplasticized poly(vinyl chloride) (PVC). The influence of the concentration of both reagents has been investigated, and crosslinking monitored by determination of the remaining sample weight after Soxhlet extraction with tetrahydrofuran. The system used (i.e., 0.5–2.0 phr peroxide with 5 to 15 phr TMPTMA) has been shown to be effective for crosslinking PVC. Gel contents of 30–40% have been obtained, premature crosslinking during processing is largely avoided, but thermal stability still needs to be improved. Considerable improvements in elevated temperature mechanical properties can be attained using an appropriate TMPTMA/peroxide concentration. The best tensile properties were obtained with 0.5 phr peroxide and 15 phr TMPTMA. Observed increases in Tg, also achievable with only 0.5 phr peroxide, but only slightly dependent on TMPTMA concentration, represent a useful increase in service temperature for the resulting compound. Lower peroxide levels may be adequate to achieve property improvements. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2657–2666, 2000  相似文献   

15.
In this article the syntheses of dimethacrylate and trimethacrylate esters as well as the mechanical and thermal properties of their copolymers with methyl methacrylate and styrene are investigated. The esters were obtained from acidic derivatives of nadic anhydride and glycidyl methacrylate. The addition reaction of glycidyl methacrylate and the acidic compound was carried out in the presence of basic catalyst—tetraethylammonium bromide. The monomers and resins were UV cured in the presence of a suitable photoinitiator which was 2,2‐dimethoxy‐2‐phenyloacetophenone. The prepared polymers were subjected to different studies concerning evaluation of their mechanical properties, thermal stability, dynamic mechanical behavior (DMA) as well as the estimation of the content of unreacted double bonds in the final product. The results proved their good thermal and mechanical properties. The degree of unsaturated bonds conversion was found to be growing with the amount of monovinyl monomer in the copolymer. Trimethacrylate‐based copolymers are characterized by a greater content of double bonds present in the obtained material compared to that of dimethacrylate‐based copolymers. As indicated by DMA the network structures of the copolymers seem to be more heterogeneous with the increasing weight fraction of trimethacrylate as well as dimethacrylate monomer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

16.
Quaternary ammonium compounds are some of the most widely used antimicrobial agents for various medical applications due to their low toxicity and broad spectrum antimicrobial activity. Various generations of poly(ethyleneglycol)diacrylate (PEGDA) based dendrimers were synthesized by Michael addition reaction of PEGDA with ethylene diamine and diethyl amine. The percentage yield of different generation of dendrimers were 70%, 66%, 60%, and 85% for G1.0 (=), G1.5 (NH2), G2.0 (=), and G2.5 (=, NEt2), respectively. Synthesized dendrimers were also copolymerized with ethyleneglycol dimethacrylate by free radical bulk polymerization at room temperature using ammonium persulphate/N,N,N′,N′‐tetramethyl ethylenediamine as a redox initiator system to form dendritic copolymer networks. These networks were quaternized with hydrochloric acid by continuously refluxing at 40°C for 6 h. Dendrimers and quaternized dendritic copolymer networks were characterized by 1HNMR, FTIR, Differential scanning calorimetry, Thermogravimetric analysis, Scanning electron microscope, swelling, and leaching studies. Synthesized quaternary ammonium dendritic copolymer networks were found to be biostable and insoluble in water and capable of killing both Gram‐positive and Gram‐negative bacteria when contaminated water was treated with them. It was also observed that antimicrobial efficiency of dendritic copolymer networks increases with the increase in nitrogen atoms in the copolymer. The dendritic copolymer network with 16 quaternary ammonium groups (G2.5 (=, NEt2): EGDMA QHCl) were highly efficient to disinfect 10 mL bacterial solution of 2000 cfu/mL within 2 min even at a very low concentration of 0.005 g/mL. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

17.
Macroporous beads, poly(ethylene glycol dimethacrylate‐co‐acrylic acid) [poly(EGDMA‐co‐AAc)], and poly(ethylene glycol dimethacrylate‐co‐hydroxyethyl methacrylate) [poly(EGDMA‐co‐HEMA)] were prepared by the suspension polymerization technique in the presence of a porogen agent. Different experimental conditions such as amount of initiator, porogen type, and temperature were studied to optimize the polymerization systems. These hydrophilic copolymers were characterized by IR spectroscopy, scanning electron microscopy, specific surface area, and swelling in water. A new parameter, H, defined as the ratio between the equilibrium weight swelling ratio (qw) and equilibrium volume swelling ratio (qv), allowed to select the reaction conditions from which matrices with high capacity of water sorption and low stretching degree were reached. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 920–927, 2001  相似文献   

18.
Poly(acrylamide‐co‐potassium methacrylate) hydrogels were prepared by free‐radical simultaneous polymerization with aqueous solutions of acrylamide (AAm) and potassium methacrylate (KMA) with a redox initiator. The copolymerization was performed with eight different compositions of KMA at a fixed concentration of oil‐soluble crosslinkers, including 1,4‐butanediol diacrylate and ethylene glycol dimethacrylate (EGDMA). For every composition of AAm/KMA copolymer, the percentage swelling, swelling equilibrium, and diffusion characteristics were investigated. The copolymers were further studied for deswelling properties. The power law relationships of the hydrogels were evaluated for variation in terms of saline concentration. The AAm/KMA copolymers were confirmed by IR spectroscopy. Thermal studies of hydrogels were performed with differential scanning calorimetry and thermogravimetric analysis. EGDMA was found to be a better crosslinker for obtaining higher swelling and deswelling properties for the AAm/KMA hydrogels. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1153–1164, 2005  相似文献   

19.
Reactive polymeric nanoparticles were formed for reinforcement of photocurable dental resin. Cross-linked polymeric nanoparticles were synthesized by emulsion polymerization of mono- (methyl methacrylate; MMA) and trifunctional (trimethylol propane trimethacrylate; TMPTMA) monomers. The nanoparticles were dispersed in bisphenol A glycol dimethacrylate (Bis-GMA) based dental resin matrix in the range of 5–25 wt% to form photocurable nanocomposites.The effect of reactive polymeric particles on the mechanical properties of photocurable dental resin was investigated. Polymerization shrinkage, polymerization shrinkage stress, viscosity, diametral tensile strength, compressive, and flexural strength of the nanocomposites have been studied.It was observed that the cross-linked nanoparticles significantly influenced the mechanical properties of the reinforced dental resin nanocomposites.  相似文献   

20.
Copolymers of butyl acrylate (BA)‐methyl methacrylate (MMA)‐acrylic acid (AA) and intraparticle crosslinking agents containing N‐methylol acrylamide (NMA) and ethylene glycol dimethacrylate (EGDMA) were prepared by emulsion copolymerization. After that, films were prepared from the mixture of copolymers and the interparticle crosslinking agents. The interparticle crosslinking agents were prepared from hexamethylene diisocyanate and aziridine ethanol. Mixtures of the copolymer and the interparticle crosslinking agent were cast to films and crosslinked in a convection oven. The effects of the contents of the intra/interparticle crosslinking agents were also evaluated. By increasing the contents of EGDMA, roughness of the films was increased because of the effects of EGDMA acting as an intraparticle crosslinking agent. By increasing the contents of the interparticle crosslinking agent, roughness was also increased by the reaction between the copolymers and interparticle crosslinking agent. Tensile strength and water and chemical resistance of the film were increased, whereas elongation of film was decreased by increasing the contents of interparticle crosslinking agents. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

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