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1.
以商业化芳族聚合物聚砜(PSf)、氯甲基辛基醚(CMOE)和1-甲基咪唑为原料,通过简单可控的氯甲基化和咪唑钅翁化反应,制备接枝型聚离子液体——咪唑钅翁化聚砜(PSf-g-[MIm][Cl]),以其为分离层制备PSf-g-[MIm][Cl]膜。通过1HNMR、SEM与TGA对膜进行了表征,并考察了咪唑钅翁化程度(DIm)、操作温度、操作压力对膜性能的影响。结果表明:该膜材料具有较好的压力稳定性,可耐受0.6 MPa的压力,并且咪唑钅翁(MIm)基团含量会极大地影响其性能,随着DIm的提高,膜内MIm基团逐渐形成连续的传递通道,CO_2渗透系数和选择性显著提高。在DIm=172%、操作温度25℃、操作压力0.4 MPa及增湿条件下进行膜性能测试,CO_2渗透系数达到66.4 barrer,CO_2/N_2选择性(渗透系数的比,下同)为118.4。  相似文献   

2.
采用聚醚砜(PES)、15-冠-5及添加剂聚乙二醇和氯化锂为原料,以N,N-二甲基乙酰胺为溶剂,用相转化法制备了Na+识别型复合膜。采用扫描电镜和傅立叶变换红外光谱对制得的复合膜进行结构和成份表征;采用杯式超滤器在一定的操作压力下测定纯水、NaCl溶液和CaCl2溶液透过冠醚/PES复合膜的水通量并测定滤液中溶质的浓度,以确定其分离性能。结果表明,15-冠-5能与聚醚砜形成稳定的复合膜;冠醚/PES复合膜具有良好的亲水性,有较大的水通量,能够选择性地识别Na+,对Na+具有良好的截留性能,而对Ca2+无截留性能。本研究结果对于钠离子识别膜的进一步设计制备和应用具有重要参考价值。  相似文献   

3.
基于逆热致相分离(RTIPS)工艺制备聚醚砜(PES)微孔膜,探究纳米TiO2和多巴胺对PES微孔膜分离性能的影响。结果显示,80℃凝固浴工艺下得到的微孔膜均呈现100%海绵结构,复合膜表皮最小孔径为300 nm。添加0.5%纳米TiO2的复合膜(MTN-0.5)对亚甲基蓝的去除率最高,为99.1%,流量恢复率95.3%;额外添加1%多巴胺(MTN-0.5/1)的复合膜对牛血清蛋白(BSA)分离率最高,为82.2%,流量恢复率96.6%。改性后复合膜的防污性能得到明显提高。  相似文献   

4.
韩光鲁  路宽  吕杰  张永辉  陈墨涵 《化工进展》2022,41(7):3801-3807
以二元醇(乙二醇、1,3-丙二醇和1,4-丁二醇)为交联剂,通过抽滤的方式在涂覆盐酸多巴胺的聚醚砜(PES)支撑层上制备了共价交联的羧基化石墨烯/聚醚砜(CG/PES)复合膜。稳定性测试证明盐酸多巴胺的涂覆和二元醇的交联显著提高了分离层和支撑层以及CG纳米片间的结合力。采用扫描电子显微镜、X射线衍射仪、X射线光电子能谱仪和水接触角测试仪对复合膜的物化性质和微观形貌进行了表征。结果表明,所得复合膜的分离层连续无缺陷,厚度在60~64nm之间。二元醇与CG纳米片上的羧基成功发生反应,将CG纳米片锚固在一起。交联剂的引入没有大幅降低亲水性且实现了对分离层层间距的有效调控,随二元醇分子尺寸增加,所得复合膜的层间距由0.761nm提高到0.778nm。CG/PES复合膜对正丁醇/水混合物具有优良的渗透汽化分离性能。在料液温度为50℃、料液中水的质量分数为10%时,三种交联剂所得复合膜的渗透通量分别达到0.79kg/(m2·h)、0.87kg/(m2·h)和0.96kg/(m2·h),而分离因子比未交联的复合膜高一个数量级。15天的...  相似文献   

5.
聚离子液体是一种具有较高CO2选择性的新型膜材料,然而,由于可聚合离子液体的种类少、价格昂贵,难以实现工业应用。对此,本文提出以商业化芳族聚合物聚砜(PSf)为基础材料,通过简单可控的氯甲基化和咪唑鎓化反应,制备接枝型聚离子液体—咪唑鎓化聚砜(PSf-g-[MIm][Cl])膜。研究了咪唑鎓化程度、操作温度、操作压力对膜性能的影响,结果表明该膜材料具有较好的压力稳定性,并且咪唑鎓(MIm)基团含量会极大的影响其性能,随着咪唑鎓化程度的增加,膜内MIm基团逐渐形成连续的传递通道,CO2渗透系数和选择性显著提高。本文制备的聚离子液体,咪唑鎓化程度最高达172%,具有良好的成膜性,在25 ℃、0.4 MPa以及增湿条件下进行测试,CO2渗透系数达到66.4 barrer,CO2/N2选择性为118.4。  相似文献   

6.
聚醚砜(PES)是一种带有苯环的高分子材料,比较容易进行功能改性。以1,4-二氯甲氧基丁烷为氯甲基化试剂,N-甲基咪唑为季铵化试剂,对PES进行季铵化改性,使其成为一种表面带有电荷的功能材料。采用红外光谱和核磁氢谱分析表征了PES的氯甲基化和季铵化程度,并测试了样品Zeta电位、静电荷、离子交换量和接触角等性能。结果表明,季铵化聚醚砜膜的离子交换量、静电荷和Zeta电位值皆与季铵化程度呈正相关关系,季铵化改性可以明显提高聚醚砜的亲水性。  相似文献   

7.
以聚醚砜(PES)膜为基膜,聚乙烯醇(PVA)交联层为功能层,制备了一种高性能聚醚砜/聚乙烯醇复合超滤膜。采用傅立叶红外光谱、原子力显微镜和接触角测试仪对PES基膜和PES/PVA复合超滤膜的结构进行表征。系统研究了运行压力、运行温度对复合超滤膜性能的影响。探索了复合超滤膜耐酸碱性能以及长期运行稳定性。进一步地,利用本文提供的复合超滤膜对油水混合乳液进行了分离,并对其油水分离效率进行了评估。结果表明,PES基膜表面涂覆PVA交联层后,可以获得表面光滑、亲水性能优异的复合超滤膜。超滤膜具有较强的耐酸碱性能,长期运行稳定性高。随着测试温度和压力的增加,超滤膜通量逐渐增大,而截留率呈逐渐降低趋势。油水乳液分离率高达98%,且具有较强的耐污染性能。  相似文献   

8.
设计了应用于全钒液流电池的尺寸筛分效应共价有机框架/聚醚砜(COF/PES)复合膜,利用纳米片的有序交错堆叠在聚醚砜支撑层上构建了具有均匀埃米级离子传输通道的连续COF分离层。连续COF层的规整刚性骨架赋予了膜极低的溶胀比,有序的埃米级孔道(有效孔径约为0.6 nm)对氢/钒离子具有精确的尺寸筛分作用。COF/PES筛分复合膜的钒渗透率仅有0.61×10-8 cm-2·s-1,质子/钒离子选择性为Nafion 212的4.0倍。电流密度为80 mA·cm-2下复合膜的能量效率达到82.9%,优于Nafion 212(81.2%)。100 mA·cm-2下的长循环测试中,复合膜电池容量保持率相比于Nafion 212电池提高了16.2%,表明连续COF/PES筛分复合膜在全钒液流电池中具有广阔的应用前景。  相似文献   

9.
设计了应用于全钒液流电池的尺寸筛分效应共价有机框架/聚醚砜(COF/PES)复合膜,利用纳米片的有序交错堆叠在聚醚砜支撑层上构建了具有均匀埃米级离子传输通道的连续COF分离层。连续COF层的规整刚性骨架赋予了膜极低的溶胀比,有序的埃米级孔道(有效孔径约为0.6 nm)对氢/钒离子具有精确的尺寸筛分作用。COF/PES筛分复合膜的钒渗透率仅有0.61×10-8 cm-2·s-1,质子/钒离子选择性为Nafion 212的4.0倍。电流密度为80 mA·cm-2下复合膜的能量效率达到82.9%,优于Nafion 212(81.2%)。100 mA·cm-2下的长循环测试中,复合膜电池容量保持率相比于Nafion 212电池提高了16.2%,表明连续COF/PES筛分复合膜在全钒液流电池中具有广阔的应用前景。  相似文献   

10.
采用相转化法、共混法和交联法,以聚醚砜(PES)、磺化聚砜(SPSF)、聚乙二醇400(PEG400)、苯乙烯马来酸酐(SMA)、N,N-二甲基乙酰胺(DMAc)、壳聚糖(CTS)为原料制备了壳聚糖(CTS)交联苯乙烯马来酸酐(SMA)/聚醚砜纳滤膜。结果表明,交联CTS后,膜表面更加致密,断面结构中微孔增多,指状孔长度延长。当CTS质量分数为25%时,复合膜的综合性能最佳。此时,和SMA/PES基膜相比,CTS/SMA/PES复合纳滤膜的水接触角由94.6°降至69°,纯水通量为10.06 L/(m~2·h),对2 g/L Na_2SO_4溶液的截留率由22.43%提高至98.87%,膜的亲水性和脱盐率等性能得到很大提高。  相似文献   

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12.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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14.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

18.
Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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