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1.
Unsensitized, photoinitiated polymerization reactions of glycidyl methacrylate from solutions of water and water–methanol with cotton cellulose fabrics were investigated. When several layers of cotton fabrics were immersed in solutions of glycidyl methacrylate and only the surface layer was exposed to light, polymerization reactions were initiated in this layer and also initiated in inner layers of fabrics, probably by chain transfer reactions. Photoinitiated (350 nm, 24 W, 34 min) polymerizations of glycidyl methacrylate (7.5 vol-%) from water (43 vol-%)–methanol (57 vol-%) with cotton fabrics in one-, three-, and six-layered configurations were: one-layered, 32% polymer; three-layered, 30%, 27%, and 25% polymer; and six-layered, 29%, 25%, 22%, 20%, 14%, and 11% polymer. Electron-microscopic examination of the distribution of poly(glycidyl methacrylate) within the cotton fibrous structure showed that polymer was distributed throughout the cross section of the fiber. At the surface of the fibers, the polymer tended to be more concentrated than within the cross section of the fibers and to encapsulate them. Photoinitiated polymerization reactivities of several vinyl monomers from solution with cotton cellulose fabrics were compared with those of glycidyl methacrylate as follows: methyl methacrylate > glycidyl methacrylate > diacetone acrylamide > 1,3-butylene dimethacrylate > methacrylic acid > acrylonitrile > divinylbenzene. 相似文献
2.
Glycidyl methacrylate was graft-copolymerized onto cotton cellolose using both photo-and chemical-initiation techniques using different initiators. The photoinitiators used were uranyl nitrate, ceric ammonium nitrate, and benzoin ethyl ether, whereas the chemical initiators used were ceric ammonium nitrate and potassium persulfate. Optimization of various parameters of grafting, viz., time, temperature, initiator, and monomer concentrations, was carried out. Ceric ammonium nitrate gave the maximum and almost identical values of graft add-on, by both grafting techniques, at equivalent cocentration of the monomer. Use of optimized conditions of ceric ammonium nitrate-photoinitiated grafting for sodium hydroxide-swollen substrate as well as for grafting baths incorporating acids enhanced the graft level. © 1994 John Wiley & Sons, Inc. 相似文献
3.
UV-radiation-induced graft-copolymerization of cotton cellulose was carried out with glycidyl methacrylate (GMA) using ceric ammonium nitrate (CAN) as a photoinitiator as well as a chemical initiator. With increase in the graft add-on, breaking load and moisture regain of cotton decreased, so also its thermal stability. The fiber surface changes due to grafting were ascertained by X-ray diffraction and scanning electron microscopy. © 1995 John Wiley & Sons, Inc. 相似文献
4.
Syntheses of new adducts from glycidyl methacrylate and the following amines: aniline, p‐phenylenediamine, 4,4′‐oxydianiline, 4,4′‐diaminodiphenylmethane, 4,4′‐diaminodiphenyl sulfone, 4,4′‐thiodianiline, and 4,4′‐diaminodicyclohexylmethane, are presented. These adducts were copolymerized with glycidyl methacrylate. The curing process was initiated thermally and by UV light. Thermomechanical properties of the obtained compositions were studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2461–2466, 2005 相似文献
5.
Polyhexamethylene guanidine hydrochloride (PHMG) oligomer is attracting increasing attention for its highly efficient biocidal activity and nontoxicity. To make it bearing carbon‐to‐carbon double bonds and enlarge its application in production of antimicrobial materials via copolymerization, PHMG oligomer was modified via reaction with glycidyl methacrylate (GMA). The influence of reaction parameters on the conversion rate of GMA was investigated using ultraviolet absorption spectroscopy. The structures of PHMG oligomer before and after modification were characterized by Fourier transform infrared spectrometry, Raman spectrometry, nuclear magnetic resonance spectrometry, and electrospray ionization time‐of‐flight mass spectrometry. The results show that carbon‐to‐carbon double bond is successfully introduced into the modified PHMG oligomer. At a feeding molar ratio of GMA to PHMG of 1.0, the conversion rate of GMA reached up to 75% after 60 h of reaction at 60°C in dimethyl sulfoxide. Also, there is an activity difference in the different aminos of PHMG oligomer: the primary amino is ready to react with epoxy of GMA, while the guanidyl amino hardly reacts with GMA due to the p‐π conjugation. Furthermore, the modified PHMG oligomer was used as comonomer to synthesize acrylonitrile copolymer, showing excellent antimicrobial activity against Staphylococcus aureus. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
6.
The ability of Fe2+-thioureadioxide-H2O2 redox system to induce polymerization of perfluoroheptyl methacrylate (PFHMA) and glycidyl methacrylate (GMA) individually as well as in binary mixtures was investigated under different conditions. Results obtained indicated that (a) PFHMA monomer could substantially be polymerized with cotton cellulose only in presence of GMA, (b) maximum contribution of PFHMA in the polymer add-on occurred upon using PFHMA mixture at a ratio of 50:50 at 80°C, (c) presence of PFHMA along with GMA offsets the fast termination rate of the latter as temperature increased from 60° to 90°C, (d) GMA activated PFHMA while the latter adversely affected GMA, (e) none of the PFHMA/GMA mixtures at ratios 2:8, 5:5, 8:2 showed synergetic effects, (f) H2O2 concentration of 0.01% and thioureadioxide concentration of 0.04% constituted the optimal concentrations for polymerization of PFHMA/GMA at a ratio of 5:5, and (g) the polymerization reaction proceeded initially very fast, then levelled off. (h) The water/oil repellency of the copolymerized cotton samples relied on the percent of PFHMA in total percent polymer add-on; these properties attained maximum at 4.25% PFHMA in a total polymer add-on of 22.5%. 相似文献
7.
Sang-Wook Park Byoung-Sik Choi Dae-Won Park Seong-Soo Kim Jae-Wook Lee 《Korean Journal of Chemical Engineering》2007,24(6):953-959
A soluble copolymer-supported catalyst containing pendant tetrahexylammonium chloride was synthesized by the radical copolymerization
of p-chloromethylated styrene with styrene followed by the addition reaction of the resulting copolymer with trihexylamine. Initial
absorption rate of carbon dioxide into glycidyl methacrylate (GMA) solutions containing the catalyst was measured in a semi-batch
stirred tank with a plane gas-liquid interface at 101.3 kPa. The reaction rate constants of the elementary reaction between
carbon dioxide and GMA were evaluated from analysis of the mass transfer mechanism accompanied by the elementary reactions
based on film theory. Solvents such as toluene, N-methyl-2-pirrolidinone, and dimethyl sulfoxide influenced the reaction rate constants. Furthermore, this catalyst was compared
to monomeric tetrahexylammonium chloride under the same reaction conditions. 相似文献
8.
The melt grafting of glycidyl methacrylate (GMA) onto powdered isotactic polypropylene (PP) in a Haake Rheocord RC90 mixer was studied. Grafting degrees were determined by nonaqueous back titration of trichloroacetic acid with sodium hydroxide. The extent of degradation and crosslinking of PP during grafting was indicated by the melt-flow rates (MFR) of the grafted samples. The influences of GMA concentration, initiator type and concentration on grafting degree, reaction efficiency, and degradation were evaluated. A novel method was developed to obtain a high grafting degree with little degradation of PP using acrylamide (AM) as the initiating agent. The grafting process occurred before or during the melting of PP (i.e., solid-state grafting), at which temperature crosslinking is preferred over chain scission. Primary free radicals generated from the rapid decomposition of AM have a higher tendency to attack GMA molecules than PP chains. At the same estimated amount of primary radicals, both grafting degree and grafting efficiency increase with decreasing decomposition temperature of the initiator (for the same decomposition half-life) in the order of AM > benzoyl peroxide (BPO) > 2,5-di(t-butylperoxy)-2,5-dimethyl-3-hexyne (LPO). FunctionalizedPP with the desired grafting degree and little degradation of PP could be obtained by the use of mixed initiators. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1957–1963, 1998 相似文献
9.
Jeong-Yeol Moon Jeong-Gyu Yang Sung-Mi Jung Dae Won Park Jin-Kook Lee 《Korean Journal of Chemical Engineering》1997,14(6):507-512
This study is related to the investigation of the characteristics of quaternary ammonium salt catalyst on the addition reaction
of carbon dioxide and glycidyl methacrylate (GMA) to form (2-oxo-l,3-dioxolan-4-yl) methyl methacrylate (DOMA). Among the
salts tested, the ones with higher alkyl chain length and with more nucleophilic counter anion showed a higher catalytic activity.
The DOMA monomer was obtained in non polar solvent like toluene and cyclohexane, while poly (DOMA) could be directly obtained
in aprotic dipolar solvent such as DMF. In order to facilitate recovery of catalyst, polymer-immobilized quaternary ammonium
salt was prepared by copolymerization of styrene (ST), divinylbenzene (DVB) and vinyl benzene chloride (VBC). The catalyst
with 2 wt% of DVB, 25 wt% of VBC and quaternized tributyl amine showed the highest catalytic activity, and its activity was
maintained even up to 10 successive experimental runs. 相似文献
10.
Summary Copolymers containing epoxy and oxime-urethane groups were prepared by copolymerization of glycidyl methacrylate (GMA) and benzophenone oxime allylurethane (BAU). The physical properties of these copolymers were characterized by GPC, NMR and DSC analyses. Photo-crosslinking reaction of the copolymers were studied by measuring the insoluble fraction of copolymer films under various reaction conditions. The degree of cross-linking reaction increased with irradiation time, heating temperature and the amount of BAU units in the copolymer. UV and IR absorption spectral studies indicate that thermal cross-linking reaction of the copolymer was catalyzed by the pendant photogenerated amines. Received: 3 March 1998/Revised version: 7 April 1998/Accepted: 15 April 1998 相似文献
11.
Summary Glycidyl methacrylate (GMA) random copolymers with methyl acrylate (MA), ethyl acrylate (EA), n-butyl acrylate (BA), methyl
methacrylate (MMA), ethyl methacrylate (EMA) and n-butyl methacrylate (BMA) were synthesized by solution free radical polymerizations,
at 70±1 °C using α,α’-azobis(isobutyronitrile) as an initiator to give the copolymers I – VI in good yields. The copolymer
compositions were obtained using related 1H NMR spectra and the polydispersity indices of the copolymers determined using gel permeation chromatography (GPC). Tris(trimethylsilyl)methyl
(Tsi=trisyl) groups were then covalently attached to the obtained copolymers as side chains by ring opening reaction between
excess of TsiLi and expoxide groups of GMA units to give the copolymers ITsi – VITsi in good yields. In the coupling reaction, the TsiLi reacted selectively with the epoxy groups of the backbone polymer rather
than with the carbonyl groups of the backbone. This method of preparing functionalized silanes is limited by the readiness
with which TsiLi abstracts a proton, if one is available, rather than attacks at carbon. In addition in the reaction with
epoxides, the product alkoxide can transfer a silyl group from carbon to oxygen or ring opening polymerization. However these
were shown not to occur at the conditions of interest here. The epoxy group possesses a higher reactivity for the TsiLi than
the ester and chloromethyl groups. The ring opening reaction between the epoxy group and the TsiLi is simple and fast. All
the resulted polymers were characterized by FT-IR and 1H NMR spectroscopic techniques. The glass transition temperature (Tg) of all copolymers was determined by differential scanning
calorimetry (DSC) apparatus. All the polymers containing trisyl groups showed a high glass transition temperature in comparison
with unmodified copolymers (I – VI). Attaching the tris(trimethylsilyl)methyl group to macromolecular chain should lead to
important modifications of polymer properties such as gas permeability and perm selectivity parameters. 相似文献
12.
Polymer grafting is a well-known method for surface modification. It improves the interfacial adhesion of the particle with the epoxy. In this study, aluminum oxide (Al2O3) was functionalized with vinyltriethoxysilane (VTES) to graft the carbon double bond for further polymerization. Then, glycidyl methacrylate (GMA) was polymerized to graft poly(glycidyl methacrylate) (PGMA) onto the surface of Al2O3 using the carbon double bond grafted in the previous step. Finally, 4.4′-diaminodiphenylmethane (DDM) was applied to bridge epoxide groups contained in the PGMA and the matrix. Consequently, the thermal conductivity of the composites increased about 320%. 相似文献
13.
Frank Schneider Sergey Piletsky Elena Piletska Antonio Guerreiro Mathias Ulbricht 《应用聚合物科学杂志》2005,98(1):362-372
The synthesis and comparative characterization of molecularly imprinted polymers (MIPs) in two different formats, as thin layers grafted to the entire surface of polypropylene microfiltration membranes and as conventional particles, are described. Imprinting with atrazine was performed by using itaconic acid and N,N′‐methylene‐bisacrylamide as functional and crosslinker monomers in methanol as the solvent. Polymerization had been initiated by UV irradiation of benzoin ethyl ether and driven to low monomer conversion for the thin‐layer polymers and to high monomer conversion for the bulk materials. The binding performance of MIP composite membranes and of MIP particles packed into cartridges was evaluated in solid‐phase extraction (SPE) experiments of atrazin and simazin from aqueous solutions. The SPE performance depended strongly on pH and buffer concentration. Although an imprinting effect was observed for both formats, the specificity (MIP versus Blank) and the selectivity (atrazin versus simazin) were much higher for the thin‐layer composite membranes than for the bulk polymer particles. In particular, the atrazin/simazin selectivity increased from 32% for the Blank to 78% for the MIP composite membranes. A major reason is the hindered accessibility of the internal pore structure of the particles, whereas the porous filtration membranes are much more compatible with the fast SPE protocol. Furthermore, based on pKa of the functional carboxylic acid groups—from potentiometric titration and polarity of the binding environment—from fluorescent probe analysis, different properties of the imprinted binding sites can be postulated for the two MIP formats. However, the differences between MIP and Blank were much more pronounced for the thin‐layer composite membranes. The hydrophobic surface of the polypropylene membrane appeared to be a major factor affecting the binding performance of thin‐layer MIPs. The new porous composite membranes could be particularly useful as selective SPE materials in environmental, pharmaceutical, and analytical applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 362–372, 2005 相似文献
14.
The melt grafting of glycidyl methacrylate (GMA) onto high‐density polyethylene (HDPE) in the presence of free radical initiators was investigated in the batch mixer. The graft content was determined with the titration and FTIR spectroscopy. The graft content increased with the increase of peroxide and initially introduced GMA concentration. Increase of the grafted GMA content resulted in decrease of the melt index. Interestingly, there was a sudden drop of GMA grafting content with the reaction time. It is assumed that depolymerization of GMA have taken place over the ceiling temperature. The crystallinity of the prepared glycidyl methacrylate grafted high density polyethylene (HDPE‐g‐GMA) was determined by the measurement of the heat of fusion. GMA grafted site acted as defect and crystallinity of the HDPE‐g‐GMA decreased with the increase of grafting reaction. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
15.
Rubber wood was impregnated with styrene and glycidyl methacrylate (GMA) as the crosslinking monomer. Polymerization was accomplished by catalyst heat treatment. Compressive strength both in parallel and perpendicular to fiber directions was measured and improvement was observed for wood polymer composites. Bending strength in terms of Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) was measured and found improved on treatment over the untreated wood samples. Hardness for treated wood was also improved. Dynamic Mechanical Analysis (DMA) indicated an increase in interaction between wood, styrene, and GMA. Biodegradation of the treated and untreated wood samples was also determined and found to be improved on treatment. Scanning electron microscopy (SEM) study showed the wood polymer interaction. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers 相似文献
16.
In the present study, the kinetics of copolymerization reaction of propylene oxide (PO) and butylene oxide (BO) with glycidyl methacrylate (GMA) in the presence of BF3 · O(C2H5)2 catalyst were investigated. The kinetic parameters and activation energy of the copolymerization reaction were calculated. The amounts of reacting PO, BO, and GMA during copolymerization were determined by chromatographic method, because the same copolymerization conditions were carried out for them. It was determined that the copolymerization rate of PO (r0) and BO (r0) was higher than that of GMA, but activation energy (E) of GMA was higher than that of PO and BO. The rate of reaction, the rate constant, and activation energy were calculated from the amount of copolymer obtained with respect to time. The structures of synthesized copolymers were determined by the spectral and chemical analysis methods. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
17.
Copolymers of glycidyl methacrylate (monomer 1) with N-vinyl pyrrolidinone (monomer 2) were prepared at 70°C in low yield by free radical initiated solution polymerizations in ethyl acetate, 1,4-dioxane and mixtures of the two solvents. Copolymer compositions were determined by proton nuclear magnetic resonance spectroscopy. Monomer reactivity ratios were then derived using the method of Kelen & Tudos. The magnitude of r1 was relatively unaffected by solvent composition, and ranged from 4.32 to 4.53 in a random fashion. In contrast, values of r2 showed a greater relative (but still random) spread from 0.0075 to 0.0147. Copolymers prepared by batch polymerization are selectively enriched with GMA monomer. 相似文献
18.
Glycidyl methacrylate (GMA) was photografted with the low‐ and high‐density polyethylene (LDPE and HDPE) plates to provide their surfaces with autohesive and adhesive properties. The chemical composition and wettability of the GMA‐grafted LDPE and HDPE (LDPE‐g‐PGMA and HDPE‐g‐PGMA) plates remained constant above full coverage of the surfaces with grafted PGMA chains. Autohesive strength obtained with 1,4‐dioxane as a good solvent of PGMA increased with an increase in the grafted amount and substrate breaking was observed at the grafted amount of 117 μmol/cm2. The grafted amount at substrate breaking was decreased by increasing the temperature and load during heat pressing. Adhesive strength was effectively enhanced by use of multi‐functional amine compounds because of the increase in the reaction between primary or secondary amine groups and epoxy groups appended to the grafted PGMA chains. In addition, the decrease in the amine compound concentration and the increase in the number of amino groups in the amine compounds used led to the decrease in the grafted amounts at substrate breaking. Substrate breaking occurred at lower grafted amounts for the HDPE‐g‐PGMA plates than for the LDPE‐g‐PGMA plates because the location of the photografting was restricted to the outer surface region for the HDPE plate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 493–500, 2007 相似文献
19.
Technetium-99 comprises a significant health risk, since edible plants can bioaccumulate and convert it to more lipophilic
species that cannot be excreted through urine. Batch kinetics of pertechnetate removal from aqueous solutions by two samples
of crosslinked poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) functionalized with diethylene triamine (PGME-deta) was investigated at the optimum pH value
of 3.0, and the initial solution activity of 325 MBq dm−3. PGME-deta was characterized by elemental analysis, mercury intrusion porosimetry, and scanning electron microscopy. Five
kinetic models (pseudo-first, pseudo-second order, Elovich, Bangham, and intraparticle diffusion) were used to determine the
best-fit equation for pertechnetate sorption. After 24 h, PGME-deta samples sorbed more than 98% of pertechnetate present,
with maximum sorption capacity of 25.5 MBq g−1, showing good potential for remediation of slightly contaminated groundwater. 相似文献
20.
The carboxyl group containing aqueous‐based polyurethane (PU) dispersions were prepared from isophorone diisocyanate, poly(propylene glycol)‐1000, and 2,2‐dimethylol propanic acid via a PU prepolymer process. The amino content of this amino‐terminated aqueous‐based PU system was determined by a styrene oxide titration method. Glycidyl methacrylate (GMA) copolymer emulsions were prepared by an emulsion polymerization of GMA and other alkyl acrylates. The curing behavior of the GMA copolymer was demonstrated by a model reaction of the GMA copolymer with ethylenediamine. In the same token, the reaction took place between the PU amino groups and the GMA copolymer epoxides at ambient temperature and resulted in the formation of a hybridized homogeneous copolymer. This hybridized copolymer also consisted of carboxylic acid on the PU fraction after drying. Carboxylic acids of the copolymer were exchanged with calcium ion and this ionic coordination resulted in a calcium ion‐crosslinked copolymer. The physical and mechanical properties and the thermal behaviors of the hybridized copolymers were evaluated. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 903–913, 1999 相似文献