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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
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《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
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以衣康酸(IA)、马来酸(MA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为单体,以过硫酸铵为引发剂,以水为溶剂,通过自由基聚合合成了一种新型的三元共聚物,探讨了单体配比、聚合温度、引发剂用量、聚合时间等合成条件对阻垢性能的影响,确定了最佳的合成条件为:单体配比n(IA)∶n(MA)∶n(AMPS)=1∶1∶1,聚合温度80℃,引发剂占单体质量分数的5%,聚合时间2h;用红外分光光度仪分析证明得到了预期的产物结构,并测定了产物的特性黏度和固含量。通过静态法对三元共聚物的阻垢性能进行评价,在加剂量为50mg/L时阻碳酸钙率最佳可达93.6%,是一种性能优异的阻垢剂。 相似文献
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在工业生产中,冷却水循环系统的结垢会导致生产效率降低、生产成本增加以及生产不能正常进行,而加入阻垢剂是解决这一难题的有效、经济、简便的方法。因此,以马来酸(MA)、丙烯酸甲酯(MAC)、丙烯酸(AA)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为单体,水为溶剂,过硫酸钾作为引发剂合成了一种新型四元共聚物阻垢剂。研究了不同聚合条件下生成共聚物对碳酸钙阻垢性能的影响,确定了最佳合成条件。结果表明,在单体摩尔n(MA)∶n(AA)∶n(AMPS)∶n(MAC)=8∶5∶3∶4,在引发剂质量为单体总质量的7.5%,反应温度85℃,反应时间3h条件下,共聚物对碳酸钙阻垢效率达94.5%以上。 相似文献
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以马来酸酐(MA)、丙烯酸(AA)、聚丙烯(PP)单体自由聚合合成阻垢剂,研究了引发剂用量、反应物摩尔比、反应时间、反应温度对阻垢剂性能的影响.结果表明,当MA与AA摩尔比为7~8,单体PP用量为10%,引发剂用量为8%~12%时,在80 ℃时反应6~7 h合成的共聚物阻垢性能最好,阻垢率可以达到95%. 相似文献
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Silvia Schicker Daniel E. García Igor Gorlov Rolf Janssen Nils Claussen 《Journal of the American Ceramic Society》1999,82(10):2607-2612
Wet milling of Al2 O3 -aluminide alloy (3A) precursor powders in acetone has been investigated by milling Fe/Al/Al2 O3 and Fe2 O3 /Al/Al2 O3 powder mixtures. The influence of the milling process on the physical and chemical properties of the milled powders has been studied. Particle refinement and homogenization were found not to play a dominant role, whereas plastic deformation of the metal particles leads to the formation of dislocations and a highly disarranged polycrystalline structure. Although no chemical reactions among the powder components in Fe2 O3 /Al/Al2 O3 powder mixtures were observed, the formation of a nanocrystalline, ordered intermetallic FeAl phase in Fe/Al/Al2 O3 powder mixtures caused by mechanical alloying was detected. Chemical reactions of Fe and Al particle surfaces with the atmosphere and the milling media lead to the formation of highly porous hydroxides on the particle surfaces. Hence the specific surface area of the powders increases, while the powder density decreases during milling. The fraction of Fe oxidized during milling was determined to be 0.13. The fraction of Al oxidized during milling strongly depends on the metal content of the powder mixture. It ranges between 0.4 and 0.8. 相似文献
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A new ampholytic homopolypeptide, , which has one tertiary amino and two carboxyl groups in the side chain has been derived from a hydrochloride salt of poly(L-lysine). The polymer in aqueous solution seems to be in the coil form with locally extended structure (LES) at neutral pH. In both the acidic and alkaline regions, the molar ellipticity of the polymer changes as a result of change in net charge on the side chain. The conformational changes may be from the coil with LES to other coiled forms. 5–7 M NaClO4 and 80% aqueous methanol induce the α-helix in the polymer at neutral pH. Divalent cations, Cu2+ and Ca2+, do not induce any remarkably ordered structures such as α-helix or β-structure in the polymer in aqueous solution at any pH. Ultraviolet absorption studies show an absorption peak of the polymer-Cu2+ complex near 240 nm. Dependence of the peak intensity on pH at various q values () indicates the two steps of the complex formation. At q less than 0.64, the formation is described only with the first step. An average coordination number for Cu2+ at the first step was calculated to be about 2 by the method of Mandel and Leyte. The association constant of Cu2+ with the residue at the step was determined from the absorption data to be far smaller than that for the Cu2+-EDTA complex. The second step of the formation occurs in the case of large q but the absorption data for the second step cannot be obtained exactly due to precipitation. 相似文献
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Sintering kinetics of the system Si3 N4-Y2O3 -Al2 O3 were determined from measurements of the linear shrinkage of pressed disks sintered isothermally at 1500° to 1700°C. Amorphous and crystalline Si3 N4 were studied with additions of 4 to 17 wt% Y2 O3 and 4 wt% A12 O3 . Sintering occurs by a liquid-phase mechanism in which the kinetics exhibit the three stages predicted by Kingery's model. However, the rates during the second stage of the process are higher for all compositions than predicted by the model. X-ray data show the presence of several transient phases which, with sufficient heating, disappear leaving mixtures of β ' -Si3 N4 and glass or β '-Si3 N4 , α '-Si3 N4 , and glass. The compositions and amounts of the residual glassy phases are estimated. 相似文献
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Akira Akimoto 《Polymer》1974,15(4):216-218
The polymerization of vinyl chloride has been investigated using an catalyst system in the presence of various Lewis bases. Effective Lewis bases are γ-butyrolactone, diglyme and diethylenetriamine which are multidentate. The rate of polymerization is dependent not only on the basicity of the Lewis base used but also on a coordination number of one. The latter is the predominant factor. For the effect of polymeric amines, a tentative hypothesis is discussed. 相似文献
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Subsolidus phase relations were established in the system Si3 N4 -SiO2 -Y2 O3 . Four ternary compounds were confirmed, with compositions of Y4 Si2 O7 N2 , Y2 Si3 O3 N4 , YSiO2 N, and Y10 (SiO4 )6 N2 . The eutectic in the triangle Si3 N4 -Y2 Si2 O7 -Y10 (SiO4 )6 N2 melts at 1500°C and that in the triangle Si2 N2 O-SiO2 -Y2 Si2 O7 at 1550°C. The eutectic temperature of the Si3 N4 -Y2 Si2 O7 join was ∼ 1520°C. 相似文献
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The quenching technique was used to study subliquidus and subsolidus phase relations in the pseudobinary system Na2 Ti2 Si2 O11 -Na2 Ti2 Si2 O9 . Both narsarukite (Na2 TiSi4 O11 ) and lorenzenite (Na2 Ti2 Si2 O9 ) melt incongruently. Narsarsukite melts at 911°±°C to SiO2 +liquid, with the liquidus at 1016°C. Lorenzenite melts at 910°±5°C to Na2 Ti6 O13 +liquid; Na2 Ti6 O13 reacts with liquid to form TiO2 and is thus consumed by 985°±5°C. The liquidus occurs at 1252°C. 相似文献