共查询到20条相似文献,搜索用时 250 毫秒
1.
苯乙烯(St)和马来酸酐(MA)自由基引发共聚反应,生成共聚物SMA,是典型的交替共聚。在过氧化苯甲酰(BPO)引发下,以丙酮为溶剂,采用溶液聚合法合成苯乙烯-马来酸酐共聚物,并用收率作为评价标准,对反应条件进行研究。结果表明,在温度为60℃,BPO的质量分数x(BPO)=0.3%,n(苯乙烯)∶n(马来酸酐)=1∶1,w(单体)=30%,反应2 h的条件下,聚合物的收率可达到98.5%。利用化学滴定法测得聚合物中马来酸酐摩尔分数为49.91%,结合理论,证明了合成的苯乙烯-马来酸酐共聚物是一种交替共聚物。一种低温合成苯乙烯-马来酸酐交替共聚物的工艺得到开发。 相似文献
2.
以乙酸乙酯为溶剂,马来酸酐、乙醇胺、苯乙烯为单体,过氧化苯甲酰为引发剂,采用溶液聚合法合成了聚羧酸型马来酸酐–乙醇胺–苯乙烯(MA–EA–St)高分子分散剂,研究了聚合反应温度和时间、引发剂用量及酰化马来酸酐与苯乙烯的摩尔比对TiO2颗粒悬浮率的影响,获得了较佳的聚合反应条件为:n(酰化马来酸酐)∶n(苯乙烯)=1.25,聚合反应温度75°C、时间5 h,引发剂用量占单体总质量的2%。当此条件下合成的MA–EA–St分散剂用量为2.5 g/L时,TiO2颗粒的悬浮率为97.42%,达到较佳的分散效果。 相似文献
3.
4.
新型三元聚合物阻垢剂的合成及性能评价 总被引:1,自引:0,他引:1
在水溶液中,以过硫酸钾为引发剂,马来酸酐(MA)、丙烯酸甲酯(MAC)、甲基丙烯磺酸钠(SMAS)为反应单体,合成无磷聚合物(MA/MAC/SMAS)。探讨了阻垢剂投加量、阻垢实验温度对聚合物阻垢率的影响,在静态试验条件下评价了其对氧化铁的分散性能,用正交实验法确定了最佳合成条件:单体配比n(马来酸酐)∶n(丙烯酸甲酯)∶n(甲基丙烯磺酸钠)=1.5∶0.5∶0.1,引发剂用量为单体的10%(wt),反应温度为80℃,反应时间为3 h。结果表明:引发剂用量是影响聚合物阻垢率的主要因素,该聚合物具有良好的阻垢分散性,阻垢率高达90.1%, 相似文献
5.
6.
7.
8.
以马来酸酐(MA)、丙烯酸(AA)、聚乙二醇(PEG)、甲基丙烯磺酸钠(SMAS)为原料,采用水溶液聚合法得到了一种四元共聚物(MAPS)硅垢防垢剂。通过单因素实验并以硅垢防垢率为评价指标来确定共聚物最佳合成条件:单体总质量分数为30%,n(MA)∶n(AA)∶n(SMAS)∶n(PEG)=1∶1∶0.4∶0.03,引发剂投加量为8%,反应温度为85℃,反应时间为3 h。在防垢剂加量为100 mg/L时,硅垢防垢率为76%;在防垢剂投加量为60 mg/L时,碳酸钙垢防垢率为91%。 相似文献
9.
《应用化工》2022,(5):875-878
采用本体聚合的方法,以苯乙烯(St)和马来酸酐(MA)为原料制备苯乙烯-马来酸酐聚合物(SMA),采用氯磺酸进一步磺化后得到低分子量的水基钻井液降粘剂磺化苯乙烯-马来酸酐(SSMA)。研究了单体配比、聚合温度、引发剂用量以及链转移剂用量对产物降粘性能的影响。结果表明,SMA的最佳合成条件为:在St与MA的摩尔比为1∶1的条件下,聚合温度为65℃,引发剂的用量为单体总质量的1.5%,链转移剂的用量为单体总质量的4%,经磺化改性制得的SSMA降粘剂能显著降低钻井液的粘度。利用红外光谱仪、凝胶色谱仪和差热分析仪对聚合物进行表征,可知所合成的聚合物结构与设计结构基本一致,重均分子量在3 0005 000之间,分子量较低;通过热重分析曲线可知,在289℃左右失重保持在90%以上,聚合物热稳定性能良好。 相似文献
10.
《现代化工》2016,(2)
以马来酸酐(MA)、丙烯酸(AA)、对苯乙烯磺酸钠(SSS)为单体,水作溶剂,过硫酸铵为引发剂,异丙醇为链转移剂,通过自由基聚合法制备了具有阻垢性能MA/AA/SSS三元共聚物。采用红外光谱法(FTIR)和热重分析(TG)等物理手段对聚合物化学结构及热稳定性进行表征。以共聚物的阻垢率为考察指标,系统研究了单体摩尔比、反应温度、反应时间、引发剂用量、链转移剂用量等因素对其阻垢性能的影响。研究结果表明,当MA、AA、SSS的摩尔比为4∶2∶1,反应温度为80℃,反应时间为4 h,引发剂用量为单体总质量的10%,链转移剂用量为单体总质量9%时,共聚物对Ca CO_3阻垢率可达85.6%。 相似文献
11.
A series of alkali‐soluble resins were prepared from esterification reaction of styrene‐maleic anhydride copolymer (SMA) and four fatty alcohols having different alkyl chains. The critical aggregates concentration of the prepared hemiester was lower than SMA, indicating that modification of SMA resin with long alkyl chains could improve their emulsification efficiency. The detailed experiments of emulsion polymerization of methyl methacrylate and butyl acrylate using these hemiesters as sole surfactants showed that SMA‐C12‐75, SMA‐C14‐70, and SMA‐C16‐65 were good surfactants. In the end, we successfully prepared stable latexes using above three good surfactants with relatively low surfactant concentration and high solid content. Characterization of latexes by Zetasizer and transmission electron microscopy revealed that particles of these latexes have core‐shell nanostructure with average particle size below 60 nm. Compared with SMA, the improvement of emulsification efficiency of its hemiesters may come from the better hydrophilic‐lipophilic balance and steric stabilization after incorporation of long alkyl chain. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
12.
Denis Tembou Nzudie Victoria L. Dimonie E. David Sudol Mohamed S. El-Aasser 《应用聚合物科学杂志》1998,70(13):2729-2747
The composition and quantity of styrene-maleic anhydride (SMA) copolymer resins were varied in emulsion copolymerizations of methyl methacrylate and n-butyl acrylate conducted by both batch and semicontinuous processes. The resulting particle sizes and levels of coagulum were measured to determine the optimum conditions for incorporation of the SMA resins into the resulting latexes. A semicontinuous process, in which no buffer was included and the SMA was added in a second stage comonomer emulsion, was found to produce coagulum-free latexes. These recipes, however, relied on nucleation of the polymer particles by conventional surfactants [nonyl phenol poly(ethylene) oxide and its corresponding sulfate salt] with a first-stage addition of a monomer emulsion prepared with these surfactants. SMA1000, having a 1/1 ratio of styrene to maleic anhydride in its copolymer, was determined to be the preferred resin (as opposed to SMA2000 and SMA3000, having SMA ratios of 2/1 and 3/1, respectively) because it interacted the least with conventional surfactants, which allowed its ready incorporation into coagulum-free recipes. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2729–2747, 1998 相似文献
13.
14.
梳形抗盐聚合物KYPAM在大庆、胜利和华北油田的聚合物驱、三元复合驱和深部调驱现场应用中已取得很好的效果 ,各油田正在加大推广应用范围。进一步改进梳形抗盐聚合物的结构研究取得重大进展 ,增稠能力大幅度提高 ,进一步验证了梳形聚合物分子设计理论。 相似文献
15.
Cheng Chang 《Polymer》2010,51(9):1947-1953
The macro-TEMPO agent (poly(4-glycidyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl), PGTEMPO) was synthesized by anion ring-opening polymerization (ROP) of 4-glycidyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl (GTEMPO) using potassium t-butoxide as the initiator. The comb-shaped copolymer, PGTEMPO-g-PVBK, was prepared via nitroxide-mediated free radical polymerization (NMP) using PGTEMPO as macro-TEMPO agent and 9-(4-vinylbenzyl)-9H-carbazole (VBK) as the monomer. The polymerizations showed characteristics of “living”/controlled behavior. The optical properties, thermal analysis and electrochemical properties of the comb-shaped copolymers were investigated. The fluorescence and ultraviolet intensity and cyclic voltammetries of the comb-shaped copolymers with different molecular weight showed a regular order. 相似文献
16.
Three kinds of surfactants as stabilizer were applied to the preparation of electrocatalysts for direct methanol fuel cell (DMFC). The catalysts have been characterized by examining their catalytic activities, morphologies and particle sizes by means of cyclic voltammetry, chronoamperometry, X-ray diffraction and transmission electron microscopy (TEM). It is found that the surfactants with different structures have a significantly influence on the catalyst shape and activity. The catalysts prepared with non-ionic surfactants as the stabilizer show higher activity for direct oxidation of methanol. The structure-activity relationship (SAR) analysis has been explored and the effect of hydrophile-lipophile balance (HLB value) has also been discussed. 相似文献
17.
18.
A novel series of water-soluble polyester surfactants has been prepared by the polymerization of SIPM, PA, and PEG. The unique structural features of these surfactants have been confirmed by IR and NMR analyses. These water-soluble polyester surfactants have been found to exhibit excellent surface active properties including surface tension, low-foaming, solubilization, and dispersant properties for disperse dyes. 相似文献
19.
Xi-huai Qiang Lin-lin Ma Zhe Yan Hui Zhang 《Journal of surfactants and detergents》2013,16(3):321-326
A series of comb-like amphiphilic surfactants of sodium salts of fatty alcohol polyoxyvinethene monoester, i.e., SMA-g-O-3, SMA-g-O-6, SMA-g-O-10, SMA-g-O-15 and SMA-g-O-20, were prepared through the esterification modification to styrene-maleic anhydride copolymer (SMA) using fatty alcohol polyoxyethylene ether in dimethylformamide(DMF). The products of esterification modification were characterized by FTIR and GPC analysis, and the esterification reaction rate was calculated by measuring the acid values of SMA and its esterification product. Then, sodium salts of those esterification substances were applied to the leather retaining and fatliquoring process to study their effects on hydrophobicity of the treated leather fiber, such as static Water Contact Angle (WCA) on the leather surface and water absorption of the treated leather. Results showed that all the esterification rates were more than 90 %; moreover, both the WCA and water absorption of the processed chrome-tanned collagen fibers were related to the number of oxyethyl groups in the fatty alcohol polyoxyethylene ether. WCA decreases and water absorption increases instead with augmentation of the oxyethyl group number. 相似文献
20.
《Ceramics International》2020,46(15):23516-23525
Magnetite spinel nanoparticles (Fe3O4) coated titanium dioxide has been prepared by the solvo-hydrothermal method for application in dye degradation and wastewater remediation. The core-shell Fe3O4@TiO2 nanoparticles have been synthesized using titanium butoxide (TBT) and ferric chloride as precursors. In this method, firstly, magnetite nanoparticles have been prepared through a solvothermal process using ethylene glycol as a solvent. Then, titanium butoxide was used as a precursor to synthesize Fe3O4@TiO2 core-shell nanoparticles using the hydrothermal method. The surfactants that were added, in separate synthetic processes, were anionic oleic acid and Sodium Dodecyl sulfonate, and non-ionic Polyvinylpyrrolidone and Polyethylene glycol. The effects of the various surfactants on the fabrication of core-shell magnetic nanoparticles were studied. Various characterization methods have been established to examine the morphology and magnetization features of the nanostructured particles, such as XRD, FTIR, TEM, FESEM, UV-spectroscopy, and VSM, etc., which validated the formation of Titania coated magnetite nanoparticles. The TiO2 shell formation drastically reduces the saturation magnetization of the magnetic nanoparticles. The Oleic acid as a surfactant produces the smallest nanoparticles. The PVP coating is best amongst these surfactants for the retention of saturation magnetization upon coating. 相似文献