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1.
以2,4-二氯苯氧乙酸(2,4-D)为模板分子,改性壳聚糖为载体,甲基丙烯酸、丙烯酰胺、2-乙烯基吡啶为功能单体合成了3种2,4-D表面分子印迹聚合物。通过FT-IR和SEM对聚合物进行了表征,考察了3种表面印迹聚合物对2,4-D的吸附性能、吸附等温线和吸附动力学。结果表明,3种表面分子印迹聚合物对2,4-D均具有较好的吸附效果、符合Langmuir方程和准二级动力学方程。热力学分析结果表明,该吸附过程为自发、熵增和吸热过程。  相似文献   

2.
以β-环糊精(β-CD)和功能单体4-乙烯基吡啶(4-VP)制备了基于阿司匹林的超分子印迹聚合物β-CD/4-VP-MIP,通过红外光谱(FT-IR)、扫描电镜(SEM)和N2吸附-脱附仪,对所合成β-CD/4-VP-MIP的组成、形貌和比表面积进行了表征,并考察了其对阿司匹林的吸附选择性、等温吸附线及动力学。结果表明:所合成的β-CD/4-VP-MIP具有较大的比表面积和丰富的孔道结构;对阿司匹林的等温吸附过程遵从Langmuir方程,饱和吸附量为42.918 mg/g;吸附动力学遵从准二级动力学方程,吸附速率为0.002 8 g/(mg·min);热力学分析表明,该吸附过程为吸热、自发、熵增过程。  相似文献   

3.
该文以壬基酚(NP)为模板,4-乙烯基吡啶(4-VPy)为功能单体,采用表面分子印迹技术成功制备磁性分子印迹聚合物(Fe_3O_4@SiO_2-MIPs),通过正交试验优化制备条件,考察了Fe_3O_4@SiO_2-MIPs的吸附选择性、吸附等温线、吸附动力学、可重复利用性及再生性。结果表明制备的磁性分子印迹聚合物易于实现固-液分离,最优制备条件为:磁性载体投加量为2 g,温度为65℃,预组装体∶交联剂为1∶2,时间为24 h。Fe_3O_4@SiO_2-MIPs对NP具有特异选择吸附性,吸附等温线符合Sips模型,且该印迹聚合物表现出高效快速的吸附动力学特征,采用二级动力学模型可很好地拟合吸附动力学过程。该功能性吸附材料具有很好的可重复利用性和再生性能。  相似文献   

4.
韩爽 《化学试剂》2014,(8):686-688,718
以四氧化三铁为内核,在其表面包覆二氧化硅,采用表面印迹技术制备了磁性甲磺隆分子印迹聚合物(MIPs)。采用磁强计(VSM)对产物的磁性进行了表征。研究了溶液pH对印迹聚合物吸附容量的影响。通过动态平衡结合法研究了分子印迹聚合物的吸附能力。结果表明,准二级动力学模型很好地拟合了吸附动力学,相关系数r达到0.999 6,吉布斯自由能变化值为-8.481 kJ/mol。与非分子印迹聚合物相比,制备的MIPs表现出高吸附容量和快速的吸附动力学。特异性吸附实验表明分子印迹聚合物对甲磺隆具有高选择性吸附。  相似文献   

5.
以芦丁为模板分子,丙烯酰胺为功能单体,乙二醇二甲基丙烯酸酯作交联剂,偶氮二异丁氰作引发剂,在经聚乙二醇改性过的Fe3O4表面合成了芦丁磁性分子印迹聚合物。研究了磁性分子印迹聚合物在不同温度下的饱和吸附量、吸附动力学及等温吸附性能。结果表明,该磁性分子印迹聚合物对芦丁有较好的吸附性能,饱和吸附量为3.342 4 mg/g;吸附动力学研究证明磁性分子印迹聚合物对芦丁的吸附过程为液膜扩散控制;等温吸附过程符合Langmuir方程,为单分子层吸附。  相似文献   

6.
《化学工程》2021,49(7)
为有效应对环境中重金属镉的污染问题,文中采用沉淀聚合法,以Cd(Ⅱ)为印迹离子,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,通过对印迹聚合体系的条件进行系统优化,制备了系列镉离子印迹聚合物(Cd(Ⅱ)-IIPs)及相应的非印迹聚合物(NIPs),同时在竞争离子的存在下,考察了其对Cd(Ⅱ)的吸附效果及识别选择性。结果表明:以4-乙烯基吡啶(4-VP)为功能单体,模板与功能单体和交联剂的摩尔比为1∶4∶30时,制备的聚合物(Cd(Ⅱ)-IIP_9)对Cd(Ⅱ)的吸附效果最好。吸附过程主要以准二级动力学为主,更符合Freundlich多层吸附行为,吸附量为529.73 mg/g,印迹因子达1.87。说明与非印迹聚合物NIP_9相比,Cd(Ⅱ)-IIP_9对Cd(Ⅱ)具有较高的吸附量和良好的识别选择性,有望用于环境中Cd(Ⅱ)的分离去除。  相似文献   

7.
采用分子印迹技术,以苯胺为模板分子,甲基丙烯酸为功能单体,二甲基丙烯酸乙二醇酯为交联剂,制备了苯胺分子印迹聚合物。采用静态吸附法考察了影响该聚合物吸附苯胺的因素,并对等温吸附过程和吸附机理进行了判断。结果表明,该印迹聚合物对苯胺具有优良的吸附效果,在p H为6.0,底液苯胺的质量浓度为300 mg/L、吸附60min、投加量为2 g/L的条件下,该聚合物对苯胺的吸附量46.89 mg/g;该等温吸附过程符合Langmuir方程,饱和吸附量为52.52 mg/g,吸附动力学研究表明,该吸附过程符合准2级动力学方程,吸附速率常数为5.11 g/(g·min)。  相似文献   

8.
王素素  张月  李辉 《化工进展》2016,35(4):1132-1139
以Zn2+-阿魏酸-咖啡酸配合物为模板制备了双分子印迹聚合物,优化了制备条件,用傅里叶红外光谱和扫描电镜对分子印迹聚合物进行结构表征,测试了分子印迹聚合物的吸附特性,探讨了分子印迹聚合物固相萃取应用效能并对萃取条件进行了优化.结果表明,当预反应混合液中金属离子、模板总量(阿魏酸-咖啡酸摩尔比为2:3)、功能单体及交联剂用量比为1:1:3:30(摩尔比)时,所得印迹聚合物对两种模板(阿魏酸和咖啡酸)均具有最好的吸附性能,吸附量分别达51.12mg/g和70.26mg/g.吸附动力学测试表明吸附3h,分子印迹聚合物可达到吸附平衡.用分子印迹聚合物进行固相萃取时,优化的淋洗过程为1.00mL H2O、1.00mL甲醇-H2O (3/7,体积比)及1.00mL甲醇-H2O-ACN (4/4/2,体积比),洗脱溶剂为2.00mL甲醇.在优化条件下,分子印迹聚合物可同时选择富集升麻初提液中的阿魏酸和咖啡酸,二者回收率分别为92.67%和95.42%,而且产品中杂质少于用硅胶萃取所得产品.  相似文献   

9.
以凹凸棒为载体,没食子酸为模板剂,合成表面分子印迹聚合物,考察分子印迹聚合物对没食子酸的的吸附性能。结果表明,表面分子印迹聚合物对没食子酸具有高度选择性,吸附行为更符合多层吸附的Freundlich方程,吸附动力学为准一级动力学。重复使用5次,吸附效果没有明显下降。用此表面分子印迹聚合物从茶叶中提取出没食子酸,与纯品相似度为99.9%。  相似文献   

10.
以凹凸棒为载体,没食子酸为模板剂,合成表面分子印迹聚合物,考察分子印迹聚合物对没食子酸的的吸附性能。结果表明,表面分子印迹聚合物对没食子酸具有高度选择性,吸附行为更符合多层吸附的Freundlich方程,吸附动力学为准一级动力学。重复使用5次,吸附效果没有明显下降。用此表面分子印迹聚合物从茶叶中提取出没食子酸,与纯品相似度为99.9%。  相似文献   

11.
The present work continues the previous studies concerning the synthesis and characterization of molecularly imprinted polymers (MIPs) with sclareol as template and three poly(acrylonitrile‐co‐acrylic acid) (AN:AA) copolymers with different ratios between monomers as matrices. The previous studies of rheology, elemental analysis, infrared spectroscopy, size exclusion chromatography, thermogravimetry, differential scanning calorimetry, batch rebinding tests, and Scatchard analysis, which confirmed the molecular imprinting, are being completed with the current equilibrium and kinetic adsorption studies. For this purpose, eight adsorption isotherms and three kinetic adsorption models were applied to six sets of experimental data obtained after three sclareol‐imprinted adsorbents (MIPs) and three nonimprinted adsorbents (NIPs) were submitted to batch adsorption experiments. After ordering the adsorption models according to the “minimum sum of normalized errors (SNE)” criteria, it was concluded that the adsorption in sclareol imprinted AN:AA copolymers is characterized by low surface coverage, takes place on heterogeneous binding sites and is reversible, while for NIPs the results suggest a difficult adsorption and/or easiness of template extraction, and that NIPs have homogeneous, but nonimprinted micropores. For the kinetic experiments, the minimum SNE for MIPs points to the first order kinetic model, fact that suggests a physical adsorption of template molecules on the imprinted sites. POLYM. ENG. SCI., 55:1152–1162, 2015. © 2014 Society of Plastics Engineers  相似文献   

12.
以b-环糊精(β-CD)、2-羟丙基-β-环糊精(HP-β-CD)和4-乙烯吡啶(4-VP)为功能单体,以氟比洛芬为模板分子,以环氧氯丙烷和乙二醇二甲基丙烯酸酯为交联剂,采用本体聚合法制备分子印迹聚合物(MIPs),对氟比洛芬与功能单体的相互作用和MIPs的结构进行了表征,比较了3种MIPs对氟比洛芬的吸附性能. 结果表明,β-CD, HP-β-CD和4-VP与氟比洛芬之间以较强的相互作用形成复合物,通过交联、聚合形成聚合物,以HP-β-CD作功能单体所得聚合物印迹效果最佳,具有较强的特异性吸附能力,印迹因子和特异性吸附率分别为1.79和38.92%,分子印迹机制是β-CD的锥筒包结作用和羟丙基的亲和作用形成印迹空穴.  相似文献   

13.
Molecular imprinting polymers (MIPs) for artemisinin were prepared by using 3‐aminopropyltriethoxysilane and calix[4]arene bonded on silica particle surface as the functional monomers, tetraethoxysilicane as cross‐linker, and artemisinin as template. The MIPs were characterized by Fourier Transform Infrared Spectroscope and SEM. Their adsorption capacities were evaluated by static adsorption experiments. The MIPs showed high adsorption capacity and good selectivity for artemisinin. The maximum adsorption capacity of MIPs for artemisinin was 40.0 mg/g. The imprinting factor and the selective factor of the artemisinin‐imprinting polymers was 2.0 and 1.5, respectively. The imprinted film coating onto the silica surface showed a fast kinetics for recognizing and binding templates. Especially, mass transfer reaches the equilibrium within 3.5 h and the adsorption capacity of MIPs for artemisinin reached 120.0 mg/g in supercritical CO2 fluid. © 2011 American Institute of Chemical Engineers AIChE J, 2011  相似文献   

14.
Molecularly imprinted polymers (MIPs) were grafted from the surface of Fe3O4 nanoparticles containing double bond via suspension polymerization in aqueous environment, and the leakage of Fe3O4 nanoparticles from MIPs was overcome in this study. The effect of different cross‐linker on adsorption capacity of the resultant magnetic MIPs was investigated using pure trimethylolpropane trimethacrylate (TRIM) or the mixture of TRIM and divinylbenzene (DVB) as cross‐linker. Both magnetic MIPs exhibited higher adsorption capacity for the template theophylline than the corresponding non‐imprinted polymer, and Freundlich model fitted reasonably well for theophylline adsorption on both magnetic MIPs. In addition, both magnetic MIPs exhibited good recognition properties for the template theophylline versus caffeine, and the selectivity of magnetic MIPs using pure TRIM as cross‐linker (mag‐MIP‐TRIM) was much higher than those using the mixture of TRIM and DVB as cross‐linker (mag‐MIP‐TRIM and DVB). The adsorption dynamics of theophylline on both magnetic MIPs fitted well with the first‐order kinetic model, but the adsorption equilibrium on mag‐MIP‐TRIM and DVB reached faster than that on mag‐MIP‐TRIM. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

15.
利用分子印迹技术的特异性识别,采用本体热聚合,以酸碱相互作用为基本作用机理,分别以甲基丙烯酸二甲氨基乙酯(DMAEMA)、甲基丙烯酸二乙氨基乙酯(DEAM)、甲基丙烯酸-2-氨基乙基酯盐酸盐(AMA盐酸盐)、4-乙烯基吡啶(4-VP)和甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)和二乙烯基苯(DVB)为交联剂,偶氮二异丁腈(AIBN)为引发剂,乙腈为溶剂设计合成了三氯生(TCS)的分子印迹聚合物(MIPs)。吸附结果表明,其中DEAM是TCS的最佳功能单体,吸附率达到了78.5%,印迹因子达到了1.7,用DEAM作为功能单体合成的MIPs对TCS的选择性实验结果显示,对TCS的吸附容量明显高于其结构类似物,对TCS的吸附实验结果显示,5次回收后重复利用,吸附容量仅降低了5.1%,表明该MIPs可以重复使用多次。  相似文献   

16.
The preparation of indole molecularly imprinted polymers (indole‐MIPs) using 4‐vinylpyridine as functional monomer, silica gel as matrix were used to adsorb indole from fuel oil specifically. The reverse atom transfer radical polymerization (RATRP) technology was introduced to prepare the surface molecularly imprinted polymers, and the precipitation polymerization was adopted in the preparation process. The obtained indole‐MIPs were characterized by nitrogen adsorption, Fourier transform infrared spectrometry and scanning electron microscopy. The results show that indole‐MIPs were provided with the larger surface areas and more pores. The adsorption capacity of indole‐MIPs was 31.80 mg g?1 at 298 K, and the adsorption equilibrium was reached in a short time. The adsorption process was spontaneous by thermodynamic analysis, and an appropriate decrease in temperature could enhance the adsorption capacity. The adsorption process obeyed pseudo‐second‐order kinetic model by kinetics analysis. The isotherm analysis results show that both Langmuir and Sips equations were suitable to experimental data. The selective adsorption and reusable performance of indole‐MIPs were favorable. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40473.  相似文献   

17.
The 17?-estradiol-imprinted polymers using non-covalent approach with methacrylic acid as the functional monomer was prepared and characterized. The effect of porogenic solvents on the adsorption capacity and thermal stability of the molecularly imprinted polymers (MIPs) were examined. Scanning electron microscopic images showed that the synthesized MIPs were bulk porous materials. The surface areas of MIPs increased from 151?C188 to 239?C292?m2?g-1 when templates were removed by methanol using Soxhlet extraction. In addition, the MIPs prepared in chloroform had a higher adsorption capacity towards 17?-estradiol (1,212???g?g-1) than that in acetonitrile (769???g?g-1), indicating that less polar porogenic solvent is suitable for synthesis of non-covalent MIPs. FTIR showed that the carbonyl group is the major functional group in MIPs to form monomer-template complex via H-bond. In addition, only a slight decrease (< 5?%) in adsorption capacity of the MIPs was observed when incubated at 80?°C for 5?h. Analysis of the capacity factor values (??imp??) for MIPs indicated that the rebinding ability from selective recognition sites of MIPs decreased in the order 17?-estradiol?>?testosterone?>?benzo[a]pyrene?>?progesterone?>?phenol, and the ??imp?? values decreased from 2.68 to 0.63, indicating the excellent selectivity of MIPs among closely related compounds. Results obtained in this study clearly indicate that the imprinted polymer is specific for recognizing 17?-estradiol. The excellent selectivity and high adsorption capacity of 17?-estradiol-imprinted polymers open the door to develop MIPs for effective separation and adsorption of estrogenic compounds.  相似文献   

18.
ABSTRACT

In this work, diflubenzuron (DBZ) molecularly imprinted polymers (MIPs) were synthesized by precipitation polymerization. The polymers were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), dynamic light scattering (DLS). The influences of synthetic conditions including template molecules, functional monomers and crosslinker on the surface morphology, particle size and size distribution of polymers were investigated. Scatchard analysis indicated the presence of specified recognition sites in MIPs. The Sips model was fitted better to the equilibrium data of MIPs over whole concentrations. The pseudo-second-order kinetic model was well fitted to the experimental data of adsorption kinetic experiment, suggesting the chemisorption mechanism between MIPs and DBZ. Four structurally similar compounds were used for the selectivity test of MIPs. It was observed that MIPs can selectively rebind the template molecules (DBZ) under the interference of four other structurally similar compounds. The application of MIPs in solid-phase extraction (SPE) offers a method for extraction and determination of benzoylureas (BUs) pesticides in apple samples prior to high-performance liquid chromatography (HPLC) analysis.  相似文献   

19.
The target of this study was to synthesize the molecularly imprinted polymers (MIPs) of L ‐phenylalanine as the solid phases for characterization of molecular adsorption by molecularly imprinted solid phase extraction (MISPE). These MIPs, in microscale, were synthesized using thermal (40°C)‐compared with thermal (65°C)‐initiated polymerization process. Itaconic acid was chosen as the functional monomers, and either ethylene glycol dimethacrylate or trimethylolpropane trimethacrylate (TRIM) was used as the cross linker and was compared together. The influences of several parameters on the properties of the MIPs were investigated, especially physical robustness from the percentage yields and molecular adsorption from the percentage recovery by MISPE. The best yields were obtained from polymers made using TRIM and thermal (65°C)‐initiated polymerization. However, there were no significant differences in molecular adsorption. It was concluded that these parameters can be considered to synthesize MIPs for chiral separation in advance steps such as other related chromatographic techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2325–2330, 2007  相似文献   

20.
以戊唑醇(TBZ)和三唑酮(TDF)为双模板分子,甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,按摩尔比为1∶4∶20制备了戊唑醇-三唑酮双模板分子印迹聚合物(MIPs)。考察了MIPs的吸附动力学、静态吸附及亲和位点特征和选择识别性能。结果表明,MIPs可在2.5h内达到吸附平衡,Scatchard分析得出MIPs存在高低两类亲和位点,且具有良好的组选择性和特异选择性。以MIPs作为固相萃取填料,制备分子印迹固相萃取柱(MISPE)用于烟叶样品前处理,并建立MISPE-超高效液相色谱-串联质谱法检测烟叶中(戊唑醇、三唑酮、腈菌唑和三唑醇)残留的方法。结果显示,MISPE柱对戊唑醇、三唑酮、腈菌唑和三唑醇的富集效果较好,平均回收率为72%~110.3%,相对标准偏差在2.38%~7.92%(n=3)。该方法简单、选择性高,可实现对烟叶中三唑类杀菌剂残留的准确分析。  相似文献   

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