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1.
Graft polymerization of glycidyl methacrylate to polycaproamide fiber, initiated by the highly effective redox system Cu2+-H2O2, was studied. The kinetic parameters affecting the yield of grafted polyglycidyl methacrylate and the efficiency of the graft polymerization were determined. 相似文献
2.
Graft copolymerization of an ethyl acrylate (EA) and dimethylaminoethyl methacrylate (DMAEMA) monomer mixture onto water-soluble hydroxypropyl methylcellulose was investigated with potassium persulfate (KPS) as the initiator in an aqueous medium. The effects of introducing DMAEMA onto the graft copolymerization and the properties of the resulting latex that was produced were studied systematically. The optimum conditions for the graft copolymerization in terms of percentage of grafting and grafting efficiency were determined. The graft copolymer was characterized by Fourier transform infrared spectra, elemental analyses, nuclear magnetic resonance, transmission electron microscopy, and dynamic light scattering methods. The results suggest that the introduction of the DMAEMA monomer clearly accelerates the initial rate of the graft copolymerization, whereas the grafting parameters decrease significantly with increasing amounts of DMAEMA. These results can be attributed to the relatively large size of the DMAEMA molecule, its redox reaction with KPS, its hydrophilicity in water, and its chain transfer effect. The equilibrium humidity adsorption behavior and acid solubility of graft the copolymer films were also studied. 相似文献
3.
Wojciech Jakubowski Jean‐Franois Lutz Stanislaw Slomkowski Krzysztof Matyjaszewski 《Journal of polymer science. Part A, Polymer chemistry》2005,43(7):1498-1510
Atom transfer radical polymerization (ATRP) and ring‐opening polymerization (ROP) were combined to synthesize poly(?‐caprolactone‐co‐octadecyl methacrylate‐co‐dimethylaminoethyl methacrylate) copolymers possessing a triblock or random block structure. Various synthetic pathways (sequential or simultaneous approaches) were investigated for the synthesis of both copolymers. For the preparation of these copolymers, an initiator with dual functionality for ATRP/anionic ring‐opening polymerization, 2‐hydroxyethyl 2‐bromoisobutyrate, was used. Copolymers were prepared with good structural control and low polydispersities (weight‐average molecular weight/number‐average molecular weight < 1.2), but one limitation was identified: the dimethylaminoethyl methacrylate (DMAEMA) block had to be synthesized after the ?‐caprolactone block. ROP could not proceed in the presence of DMAEMA because the complexation of the amine groups in poly(dimethylaminoethyl methacrylate) deactivated tin(II) hexanoate, which was used as a catalyst for ROP. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1498–1510, 2005 相似文献
4.
Graft polymerization of 2-hydroxyethyl methacrylate was made onto plasma pretreated fabrics of cotton, silk, and polyester. Homopolymerization also took place during the graft polymerization, but the percent of the homopolymer formation was comparatively small. Therefore, kinetic analyses of graft polymerization were undertaken based on the first-order reaction of the monomer. Through a comparison of the rate constants which were obtained from the rate equation of the graft polymerization of 2-hydroxyethyl methacrylate, the dependence of plasma pretreatment on various factors and the resulting polymerization were clarified. Polymerizability was compared to that obtained with the Ce(IV) catalyst and without catalysts. 相似文献
5.
SBS与甲基丙烯酸丁酯本体接枝反应的研究 总被引:1,自引:0,他引:1
本文研究了以过氧化苯甲酰(BPO)为引发剂,甲基丙烯酸丁酯(BMA)既作溶剂又作为单体与苯乙烯-丁二烯嵌段共聚物(SBS)进行接枝共聚反应。用红外光谱、核磁共振谱及透射电镜表征了接枝共聚物(SBS-g-BMA)的组成及结构,讨论了时间、温度及SBS和BPO的用量对接枝的影响。 相似文献
6.
The radical graft polymerization of vinyl monomers from carbon black initiated by azo groups introduced onto the surface was investigated. The introduction of azo groups onto carbon black surface was achieved by three methods: the reaction of 2,2′-azobis[2-(2-imidazolin-2-yl)propane] (AIP) with (1) epoxide groups, which were introduced by the reaction of carbon black with chlorometh-yloxirane; (2) acyl chloride groups, which were introduced by the reaction of carboxyl groups on the surface with thionyl chloride; and (3) 3-chloroformyl-1-cyano-1-methylpropyl groups, which were introduced by the reaction of carbon black with 4,4′-azobis(4-cyanovaleric acid) and then thionyl chloride. The amount of azo groups introduced onto the surface by the above methods was determined to be 0.07-0.19 mmol/g. The graft polymerization of methyl methacrylate was found to be initiated by azo groups introduced onto the carbon black surface. During the polymerization, poly(methyl methacrylate) was effectively grafted onto carbon black through propagation of the polymer from the radical produced on the surface by the decomposition of the azo groups. The percentage of grafting using carbon black having azo groups introduced by method 1 increased to 40%. It was also found that the graft polymerization of several vinyl monomers such as styrene, acrylonitrile, and acrylic acid was initiated by the azo groups introduced onto the surface and the corresponding polymer was effectively grafted onto the surface. Furthermore, the effect of the amount of carbon black having azo groups on the graft polymerization was investigated. 相似文献
7.
Application of a new family of amphoteric cellulose-based graft copolymers as drilling-mud additives
A new family of amphoteric cellulose-based graft copolymers (CGADs), which were prepared by grafting acrylamide and dimethylaminoethyl
methacrylate onto sodium carboxymethyl cellulose, have been investigated for their properties as multifunctional drilling-mud
additives with respect to shale inhibition, rheological control and filtrate-loss control. For the CGADs investigated, the
shale-inhibition ability improves but the filtration-control ability weakens with increasing content of cationic groups. An
increase in the concentration of CGADs results in better inhibition and viscosity-building as well as lower fluid loss. The
pH of the medium has an effect on the inhibitive property. A comparative study among CGADs and some commercial polymeric drilling-mud
additives was also carried out.
Received: 24 February 1999 Accepted in revised form: 10 May 1999 相似文献
8.
纳米SiO_2粒子锚固偶氮引发剂及接枝聚甲基丙烯酸甲酯 总被引:5,自引:0,他引:5
对纳米SiO2 粒子锚固偶氮引发剂 ,进而引发甲基丙烯酸甲酯聚合而制备聚甲基丙烯酸甲酯(PMMA) 纳米SiO2 复合粒子进行了研究 .纳米SiO2 先用环氧型硅烷偶联剂处理 ,再与偶氮二氰基戊酸发生缩合反应而锚固上偶氮引发剂 ,通过差示扫描量热和元素分析证明了引发剂在纳米SiO2 表面的锚固 .通过改性纳米SiO2 存在下MMA的乳液聚合 ,制备得到了接枝率为 2 3 2 %、接枝效率为 36 1%的PMMA 纳米SiO2 复合粒子 .经乳液聚合后 ,纳米SiO2 粒子团聚程度减小 ,在水相中分散稳定 . 相似文献
9.
Surface modification of silica nanoparticles by UV-induced graft polymerization of methyl methacrylate 总被引:2,自引:0,他引:2
In this study we modified the surface of silica nanoparticles with methyl methacrylate by UV-induced graft polymerization. It is a surface-initiated polymerization reaction induced by ultraviolet irradiation. The resulting organic-inorganic nanocomposites were near-monodisperse and fabricated without homopolymerization of the monomer. Substantial increase in mean particle size was observed by SEM image analysis after UV-induced grafting of methyl methacrylate onto pure silica particles. FT-Raman spectroscopy and X-ray photoelectron spectroscopy studies of these materials revealed the successful grafting of methyl methacrylate onto the silica surface. The formation of a covalent bond between the grafted PMMA chains and silica surface was indicated by FT-Raman spectra. Thermogravimetric analysis of the PMMA-grafted silica particles indicated the polymer contents in good agreement with SEM photographs. 相似文献
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Methyl methacrylate was grafted onto poly(vinyl oxazoline ester) and poly(stearyl methacrylate) by a chain transfer suspension polymerization method to produce specialty polymeric products. These graft polymers should find application in powder coating, toner resin, and for encapsulating electronic components. 相似文献
12.
The graft copolymerization of methyl methacrylate onto poly-(ethylene terephthalate) using metal complexes of Mn3+, Co3+, and Fe3+ as initiators was studied. The rate of polymerization, Rp, increased with increasing complex concentrations. The rate of polymerization was also studied by varying monomer concentrations. Increasing monomer concentrations, the rate of polymerization increases significantly. The graft yield increases with increasing temperature within the range 60–75°C. The graft yield is medium dependent. A suitable kinetic scheme has been pictured and rate equations have been derived. 相似文献
13.
聚丙烯微孔膜表面修饰的葡聚糖固定化研究 总被引:3,自引:0,他引:3
糖以各种形式广泛存在于自然界,在人类的许多生理过程中起着不可或缺的重要作用.它具有优良的亲水性和生物特异性.研究表日月,将含糖单体接枝到聚丙烯微孔膜表面或通过共聚引入聚丙烯腈超滤膜,能显著提高常规高分子分离膜的抗污染能力和表面生物相容性,从而扩大其应用范围. 相似文献
14.
Marinos Pitsikalis Stella Sioula Stergios Pispas Nikos Hadjichristidis Daniel C. Cook Jianbo Li Jimmy W. Mays 《Journal of polymer science. Part A, Polymer chemistry》1999,37(23):4337-4350
Anionic polymerization techniques utilizing 1,2,4,5-tetra(bromomethyl)- benzene as the linking agent were employed for the synthesis of four-arm star polymers with poly(tert-butyl methacrylate) (PtBuMA), poly(methyl methacrylate), poly(tert-butylacrylate) (PtBuA), or poly(2-vinylpyridine) (P2VP) branches. This work was extended through the “grafting onto” method, in combination with anionic polymerization techniques, to synthesize graft copolymers consisting of polystyrene backbones and PtBuA, PtBuMA, or P2VP branches. Postpolymerization reactions were performed to produce graft copolymers with polyelectrolyte branches. Crosslinking reactions were observed in some of the graft materials several months after their preparation. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4337–4350, 1999 相似文献
15.
《European Polymer Journal》1985,21(4):415-419
Grafting of poly(glycidyl methacrylate) (PGMA) onto alginic acid was carried out using ceric ammonium nitrate as initiator, using various concentrations of monomer and initiator, and various temperatures and times. Percentage grafting, grafting efficiency and rates of polymerization, graft copolymerization and homopolymerization were evaluated in all cases. Infrared spectra for pure alginic acid, poly(glycidyl methacrylate) and the alginic acid-poly(glycidyl methacrylate) were taken to establish the occurrence of grafting. Differential scanning calorimetry was carried out for alginic acid, poly(glycidyl methacrylate), the graft copolymer and the physical mixture to establish evidence for grafting. 相似文献
16.
Irina N. Savina Bo Mattiasson Igor Yu. Galaev 《Journal of polymer science. Part A, Polymer chemistry》2006,44(6):1952-1963
Graft polymerization initiated by diperiodatocuprate(III) complex (Cu(III)) initiator was found to be an effective and convenient method for graft polymerization of vinyl monomers onto macroporous polyacrylamide gels, the so‐called cryogels (pAAm‐cryogels). The effect of time, temperature, monomer and initiator concentration during the graft polymerization in aqueous and aqueous‐organic media was studied. The graft polymerization of water‐soluble monomers as [2‐(methacryloyloxy)ethyl]‐trimethylammonium chloride, 2‐hydroxyethyl methacrylate, N‐isopropylacrylamide, and N,N‐dimethylacrylamide proceeds with higher grafting yield in aqueous medium, as compared with that in aqueous‐organic media. Graft polymerization in aqueous‐organic media such as water–DMSO solutions allows grafting of water‐insoluble monomers such as glycidyl methacrylate and N‐tert‐butylacrylamide with high grafting degrees of 100 and 410%, respectively. It was found that the deposition of initiator on the pore surface of cryogels promoted graft polymerization by facilitating the formation of the redox couple Cu(III)‐acrylamide group. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1952–1963, 2006 相似文献
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N. V. Smirnova G. A. Gabrielyan L. S. Gal'braikh 《Journal of polymer science. Part A, Polymer chemistry》1991,29(2):139-145
A new phenomenon in graft polymerization has been investigated: the complexing of growing radicals with copper ions. Graft polymerization of methacrylic acid to polycaproamide, initiated by the reversible K2S2O8–Na2S2O3 redox system in the presence of copper ions, is used as an illustration to show that the complexing of growing radicals with copper ions significantly enhances their activity. The concepts of the graft polymerization mechanism have been formulated. 相似文献