共查询到18条相似文献,搜索用时 78 毫秒
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利用正丁基锂(n-BuLi)与炭黑(CB)表面含氧基团反应制得了表面含-OLi基团的反应型炭黑,以该炭黑与聚氧乙烯-聚氧丙烯-聚苯乙烯(PEO-PPO-PS)多嵌段聚合物组成的阴离子引发体系作活性中心,研究了苯乙烯在炭黑表面的阴离子接枝聚合。FT-IR,TEM和DSC分析表明在接枝炭黑表面存在苯乙烯的聚合物。接枝炭黑在甲苯中有良好的分散稳定性。 相似文献
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乙烯基单体在炭黑表面上的接枝聚合 总被引:3,自引:0,他引:3
讨论了分别在铈离子体系,正丁基锂体系,过渡金属离子乙酰丙酮铜(Ⅱ)以及焦磷酸络锰(Ⅲ)体系的作用下,炭黑与乙烯基单体的接枝聚合.研究了引发剂浓度、单体浓度、反应时间对接枝聚合反应的影响.利用FT IR分析确证了炭黑表面的接枝反应,利用TEM表征了接枝炭黑的形态.结果表明,在所研究的多种炭黑表面接枝聚合体系中,正丁基锂体系的接枝率最高,可达200%.而各种氧化还原体素的接枝率只能达到30%左右.表面接枝后的炭黑在介质中的分散稳定性明显改善. 相似文献
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丙烯酰胺在炭黑表面接枝聚合研究 总被引:4,自引:0,他引:4
利用Ce^4+和羟甲基化炭黑组成的氧化还原引发体系,探讨了丙烯酰胺在炭黑表面的自由基水溶液接枝聚合机理。研究表明:单体浓度、硝酸浓度和铈盐用量直接影响丙烯酰胺在炭黑表面的接枝聚合,FTI和TEM分析证明:改性炭黑表面存在着聚丙烯酰胺。改性炭黑粒子的Zeta电位值与未改性炭黑粒子相同,但它与水组成的分散体具有极好的分散稳定性。 相似文献
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超声引发自由基聚合制备聚苯乙烯磺酸钠接枝炭黑 总被引:1,自引:0,他引:1
通过在超声环境下,单体苯乙烯磺酸钠发生自由基聚合,生成的聚合物长链自由基被炭黑表面捕获,制备聚合物接枝炭黑.借助红外光谱、热重、粒度、透射电镜和zeta电位分析对该接枝炭黑进行表征.同时研究超声条件对接枝率的影响.结果表明,单体聚合并接枝到炭黑表面,同时炭黑的附聚体和一些大的聚集体结构被超声破碎,平均粒径大为减小;在300W超声波输出功率下,反应1h后,接枝率达到12.8%并趋于稳定.由于接枝分子链上磺酸基的存在,接枝炭黑在水中的分散稳定性显著改善. 相似文献
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丙烯酸甲酯在炭黑表面的接枝聚合及水解 总被引:1,自引:0,他引:1
在炭黑表面接枝聚合物 ,可提高其在相应介质中的分散性[1] .乙酰丙酮合锰可以有效地引发羊毛、纤维素、淀粉等天然高分子的接枝聚合 [2~ 4 ] ,季君晖 [5]将其与羟甲基化炭黑组成引发体系 ,引发了甲基丙烯酸甲酯、丙烯酸丁酯、苯乙烯等单体在炭黑表面进行接枝聚合 .但该体系难以引发水溶性的单体 ,因此得到的接枝炭黑只能用于油性体系 .目前制备亲水性接枝炭黑大多采用 Ce4 +/羟甲基化炭黑引发体系 ,该体系对 O2 特别敏感 ,反应条件相当苛刻 .本文采用乙酰丙酮合锰与羟甲基化炭黑组成引发体系 ,引发丙烯酸甲酯在炭黑表面的接枝聚合 .在 Na… 相似文献
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Aromatic poly(amide-imide) with terminal isocyanate groups (PAINCO) was prepared by the polycondensation of trimellitic anhydride and a slight excess of 4,4′-diphenylmethane diisocyanate in N-methyl-2-pyrrolidone (NMP) at 160°C for 20 h. PAI was effectively grafted onto the surface by the reaction of PAI-NCO with carbon black: the percentage of grafting onto FW 200 and Neospectra II was determined to be 41.2 and 39.5%, respectively. When the carboxyl and phenolic hydroxyl groups on carbon black were blocked by treatment with diazomethane, the grafting of PAI-NCO onto the treated carbon black does not proceed. Therefore, it is concluded that PAI-NCO reacts with the carboxyl and phenolic hydroxyl groups on carbon black and PAI is grafted through amide and urethane bonds, respectively. The reaction of PAI-NCO with carbon black was accelerated by the addition of amines as catalyst and by raising of the reaction temperature. Thermogravimetric analysis indicated that PAI-grafted carbon black was stable in air up to about 300°C. The PAI-grafted carbon black was found to give a stable colloidal dispersion in NMP. 相似文献
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Shinji Hayashi Satoshi Handa Norio Tsubokawa 《Journal of polymer science. Part A, Polymer chemistry》1996,34(8):1589-1595
The introduction of peroxide groups onto carbon black surface was achieved through the trapping of the peroxide radicals formed by the decomposition of polymeric peroxide, such as poly(tetraethylene glycol peroxyadipate) (ATPPO), and bis-peroxide, such as 1,1′-bis (t-butyldioxy)cyclohexane (Perhexa-C), by the surface: the amount of peroxide groups introduced onto carbon black surface by the treatment with ATPPO and Perhexa-C were determined to be 0.07 mmol/g and 0.12 mmol/g, respectively. The polymerization of vinyl monomers with positive e-value, such as methyl methacrylate and 2-hydroxyethy methacrylate, was successfully initiated by the peroxide groups introduced onto carbon black surface. During the polymerization, the corresponding polymers were effectively grafted onto the surface as a result of the propagation of polymer from the surface radicals formed by decomposition of the peroxide groups. The polymerization of vinyl monomers with negative e-value, such as styrene and vinyl acetate, however, was scarcely initiated by the peroxide groups on carbon black. This may be due to the fact that surface active radicals, which were formed by the hydrogen abstraction from carbon black by fragment radicals, inhibit the polymerization of vinyl monomers with negative e-value. © 1996 John Wiley & Sons, Inc. 相似文献
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Sachio Yoshikawa Rie Nishizaka Ken'ichi Oyanagi Norio Tsubokawa 《Journal of polymer science. Part A, Polymer chemistry》1995,33(13):2251-2256
The effect of zinc chloride (ZnCl2) on the cationic polymerization of isobutyl vinyl ether (IBVE) initiated by carboxyl groups on a carbon black surface was investigated. Although the polymerization of IBVE was initiated by carboxyl groups on the surface, the rate of polymerization was small and the molecular weight distribution (MWD) of poly IBVE was very broad. The rate of the polymerization was found to be drastically increased, and 100% monomer conversion was achieved in a short time by the addition of ZnCl2. The number-average molecular weights (Mn) of the polyIBVE were directly proportional to monomer conversion in the polymerization initiated by the carbon black/ZnCl2 system. By addition of the monomer at the end of the first-stage polymerization, the added monomer was smoothly polymerized at the same rate as in the first stage. The Mn of the polymer was in excellent agreement with the calculated value, assuming the polyIBVE chain forms per unit carboxyl group on the surface and MWD was narrow (Mw/Mn = 1.2 ~ 1.3). Based on the results, it is concluded that carbon black/ZnCl2 system has an ability to initiate the living cationic polymerization of IBVE. Furthermore, it was found that polyIBVE was grafted onto the carbon black surface after the quenching of the living polymer with methanol. © 1995 John Wiley & Sons, Inc. 相似文献
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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
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Core-shell carbon black nanoparticles were prepared by surface-initiated ring-opening polymerization of ε-caprolactone. 1H NMR, 13C NMR, FT-IR, TGA, AFM, TEM and dynamic light scattering were used to characterize the core-shell carbon black nanoparticles (CB-g-PCL). TEM and AFM measurements showed that CB-g-PCL formed the core-shell structure with carbon black as the “core” and the PCL layer as the “shell”. TEM study also indicated that the core-shell carbon black nanoparticles could be homogeneously oriented in the PCL continuous phase under certain crystallization condition. 相似文献
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Abstract The grafting of poly(organophosphazenes) onto carbon black surface by the reaction of poly(dichlorophosphazene) (PDCP) with carbon black having sodium phenoxide groups was investigated. PDCP was prepared by the ring-opening polymerization of hexachlorocyclotriphos-phazene in solution using sulfamic acid as a catalyst. The introduction of sodium phenoxide groups onto carbon black was achieved by treatment of phenolic hydroxyl groups on the surface with sodium hydroxide in methanol. Poly(diphenoxyphosphazene) (PDPP) was successfully grafted onto carbon black by the reaction of PDCP with sodium phenoxide groups introduced onto the surface followed by the replacement of chlorine atoms in PDCP with phenoxy groups. The percentage of grafting onto carbon black increased to 206% at 30°C after 12 h. It was found that only 1.4% of sodium phenoxide groups on carbon black surface was used for the grafting of PDCP because of the blocking of the surface by grafted polymer chains. Poly(diaminophenylphosphazene) and poly-(diethoxyphosphazene) were also grafted onto carbon black surface by the treatment of PDCP-grafted carbon black with aniline and sodium ethoxide, respectively. Poly(organophosphazenes)-grafted carbon blacks produced stable colloidal dispersions in good solvents for grafted polymers. Furthermore, thermogravimetric analysis indicated that poly-(organophosphazenes)-grafted carbon blacks were stable in air about 300°C. 相似文献
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Qiang Yang Li Wang Wei‐dong Xiang Jun‐feng Zhou Qiao‐hua Tan 《Journal of polymer science. Part A, Polymer chemistry》2007,45(15):3451-3459
Pristine carbon black was oxidized with nitric acid to produce carboxyl group, and then the carboxyl group was consecutively treated with thionyl chloride and glycol to introduce hydroxyl group. The hydroxyl group on the carbon black surface was reacted with 2‐bromo‐2‐methylpropionyl bromide to anchor atom transfer radical polymerization (ATRP) initiator. The ATRP initiator on carbon black surface was verified by TGA, FTIR, EDS, and elemental analysis. Then, poly (methyl methacrylate) and polystyrene chains were respectively, grown from carbon black surface by surface‐initiated atom transfer radical polymerization (SI‐ATRP) using CuCl/2,2‐dipyridyl (bpy) as the catalyst/ligand combination at 110 °C in anisole. 1H NMR, TGA, TEM, AFM, DSC, and DLS were used to systemically characterize the polymer‐grafted carbon black nanoparticles. Dispersion experiments showed that the grafted carbon black nanoparticles had good solubilities in organic solvents such as THF, chloroform, dichloromethane, DMF, etc. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3451–3459, 2007 相似文献
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Gang Wei Nozomu Sasage Yusuke Kusanagi Kazuhiro Fujiki Takeshi Yamauchi Norio Tsubokawa 《Journal of polymer science. Part A, Polymer chemistry》2008,46(12):4218-4226
The surface grafting of hyperbranched cyclotriphosphazene polymer onto silica nanoparticles and carbon black was investigated. The grafting of hyperbranched cyclotriphosphazene polymer onto these surfaces was achieved by the repeated reactions of hexachlorocyclotriphosphazene with hexamethylenediamine from surface amino groups and sodium carboxylate groups, respectively. The percentage of grafting onto silica and carbon black surfaces exceeded 760 and 390%, respectively. However, it proved difficult to achieve the theoretical growth of cyclotriphosphazene polymer from these surfaces because of steric hindrance. The introduction of sulfonic acid groups was successfully achieved by the reaction of terminal chlorophosphazene groups of the hyperbranched polymer‐grafted silica and carbon black with sulfanilic acid. The content of sulfonic acid groups introduced onto silica and carbon black surfaces was 4.98 mmol/g and 5.70 mmol/g, respectively. The sulfonated cyclotriphosphazene polymer‐grafted carbon black was extremely hydrophilic, yielding stable colloidal dispersions in polar solvents. The sulfonated cyclotriphosphazene polymer‐grafted silica and carbon black showed ionic conductivity, with the conductance increasing exponentially with increasing relative humidity and temperature. This study may offer important leads in the application of silica nanoparticles and carbon black in polymeric membranes for fuel cells. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4218–4226, 2008 相似文献