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1.
To chemically bond β‐cyclodextrin (β‐CD), which can form inclusion complexes, acrylamidomethyl CD (CD–NMA) obtained from the acid‐catalyzed reaction of N‐methylolacrylamide (NMA) and β‐CD was grafted onto cellulose fibers using CeIV as the initiator. The double‐bond content of CD–NMA increased with increase in the NMA/CD mol ratio, and a CD–NMA containing a maximum of three molecules of NMA bonded to a CD molecule could be obtained. Since the grafting condition is acidic, the hydrolytic stability of CD–NMA in aqueous nitric acid was studied. The temperature of hydrolysis proved to have a greater effect on the depletion of double bonds from CD–NMA compared with the concentration of the acid. Thus, CD–NMA was grafted onto cellulose fibers at a low temperature, and FTIR analysis of the CD–NMA‐grafted cotton fibers confirmed the chemical bonding of CD–NMA molecules to cellulose. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 438–446, 2001  相似文献   

2.
The purpose of our research was to prepare nanoencapsulated PET textile materials, which would be used as odor carriers (underwear and bed sheets with aromatherapy activities) or would act as malodorous absorbers (absorption of cigarette smell). We grafted β‐cyclodextrin onto PET textile materials by using a polyfunctional reagent 1,2,3,4‐butanetetracarboxylic acid. To reduce the curing temperature of the reaction, catalysts such as sodium hypophosphite and cyanamide were used. We prepared nanoencapsulated polyester textile materials with increased adsorption capacity and with delayed release of volatile or active compounds. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

3.
BACKGROUND: Because of its high demand for use in pharmaceutical products, cosmetics, soil remediation technologies, etc., randomly methylated β‐cyclodextrin (RM‐β‐CD) is one of the most important cyclodextrin (CD) derivatives. The aim of this present work is to use a green and commercially available approach to obtain RM‐β‐CD. Compared with other methylated CDs, RM‐β‐CD with an asymmetric molecular structure has higher water solubility. When the degree of substitution (DS) is about 1.8, the solubility tends to increase with increasing temperature and is suitable for pharmaceutical applications. RESULTS: RM‐β‐CD was synthesized using a green approach with ideal DS equal to 1.79. The one step process of β‐cyclodextrin methylation by CH3Cl instead of (CH3)2SO4 at mild temperature (80 °C) and pressure (1.60 MPa) with a good yield (78%), is convenient and environmentally friendly. The mixture of RM‐β‐CD obtained contained five compounds with various DS, from which the main compound with a DS equal to 1.8 was separated by column chromatography. The compounds were carefully characterized by infra‐red, NMR and mass spectrometry. CONCLUSIONS: The one‐step process to RM‐β‐CDs with CH3Cl is more economical, more efficient and less noxious than the usual method using (CH3)2SO4. Moreover, this approach avoids some poisonous residual materials and meets the demand for protecting the environment. Copyright © 2009 Society of Chemical Industry  相似文献   

4.
A novel linear water‐soluble β‐cyclodextrin polymer has been prepared by grafting β‐cyclodextrin on poly[(methyl vinyl ether)‐alt‐(maleic anhydride)]. First, lithium hydride was used to obtain the mono‐alkoxide β‐CD. Grafting of β‐CD derivatives to the polymer backbone was then carried out by an esterification method. Using this method, polymers containing various amounts of β‐CD were synthesized. The resulting grafted polymers were characterized by two complementary methods, 1H NMR and IR spectroscopy. The first was used to calculate the degree of substitution for the low amounts of β‐CD. The second method was very useful to evaluate the degree of substitution and the molar ratio of CD especially for high amounts of grafting. Our results indicate good agreement between both methods for intermediate rates. Copyright © 2004 Society of Chemical Industry  相似文献   

5.
A novel star polymer with β‐cyclodextrin (β‐CD) core and polyacrylonitrile arms and its metal complexes (Cu2+, Zn2+, and Ag+) were synthesized and characterized by means of infrared spectra, ultraviolet, GPC, X‐ray photoelectron spectroscopy, differential scanning calorimetry, cyclic voltammetry, and electron spin resonance. The results indicate that the monomers of acrylonitrile were initiated by functionalized β‐CD. The thermal properties of star polymer were improved greatly after transitional metal ions were introduced into it. The novel star polymer metal complexes possess properties of metal ions, polymer, and β‐CD. Furthermore, it shows stable electrochemical activity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

6.
In this study, novel tumor targeting nanocarriers comprised of chitosan (CS)/β‐cyclodextrin (β‐CD) magnetic nanoparticles were prepared to improve the photodegradable stability and bioavailability of hydrophobic drug. Resveratrol (Res) with photodegradable and hydrophobic properties was selected as a model drug. The photodegradation rate of Res in Fe3O4 nanoparticles solution was 7.8 times lower than that in the ethanol solution. In addition, the value of the saturation magnetization of CS/β‐CD nanoparticles was found to be 19.56 emu/g with characteristic of superparamagnetism. Approximately 90% Res was entrapped into the CS/β‐CD magnetic nanoparticles with the size distribution ranging from 200 to 359 nm, and the nanoparticles were spherical in shape with high zeta potentials. Furthermore, the formation of CS/β‐CD nanoparticles showed a sustained release in vitro. These results indicated that the obtained CS/β‐CD magnetic nanoparticles were a promising magnetic targeting carrier for photodegradable and hydrophobic drugs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45076.  相似文献   

7.
The crystalline morphology and dynamical crystallization of antibacterial polypropylene composite and pure polypropylene were investigated via differential scanning calorimeter (DSC), wide angle X‐ray diffraction (WAXD), and real‐time hot‐stage optical microscopy (OM). The results reveal that the crystalline morphology of antibacterial PP composites changes with variations of the crystallization conditions and compositions. The crystalline phase consists of both α‐PP and β‐PP crystals. The content of β‐PP decreases with the increase in antibacterial agent content and cooling rate. With the addition of β‐nucleating agent, the morphologies of all dynamically crystallized antibacterial PP composites show no obvious spherulitic morphology, and the decrease of crystal perfection and the increase of nucleation density of antibacterial PP composite system could be observed. With the increase of antibacterial agent content, the overall crystallization rates of the antibacterial PP composite increase dramatically, while the content of β‐PP in all antibacterial PP composite decrease distinctly under given cooling conditions. These results can be explained by the interruptive effect of antibacterial agent on interactions of β‐nucleating agent components and the obstructing effect of antibacterial agent on the mobility of PP chains in melts. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

8.
Two new adsorbents [β‐cyclodextrin–chitosan (β‐CD–CTS) and β‐cyclodextrin‐6–chitosan (β‐CD‐6‐CTS)] were synthesized by the reaction of β‐cyclodextrin (β‐CD) with epoxy‐activated chitosan (CTS) and the sulfonation of the C‐6 hydroxyl group of β‐cyclodextrin with CTS, respectively. Their structures were confirmed by IR spectral analysis and X‐ray diffraction analysis, and their apparent amount of grafting was determined by ultraviolet spectroscopy. The adsorption properties of β‐CD‐CTS and β‐CD‐6‐CTS for p‐dihydroxybenzene were studied. The experimental results showed that the two new adsorbents exerted adsorption on the carefully chosen target. The highest saturated capacity of p‐dihydroxybenzene of β‐CD‐CTS and β‐CD‐6‐CTS were 51.68 and 46.41 mg/g, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 860–864, 2004  相似文献   

9.
10.
Novel acrylic monomers (β‐CD‐A and β‐CD‐6‐EA) containing β‐cyclodextrin (β‐CD) with different extent of substitution were prepared by using dicyclohexylcarbodiimide (DCC) as a condensation agent at room temperature. Two kinds of functional hydrogels were also synthesized by copolymerization of β‐CD‐A and β‐CD‐6‐EA with acrylic acid (AAc) using a redox initiator system in aqueous solution. The nuclear magnetic resonance (1H NMR), infrared spectroscopy (IR), thermogravimetric analysis (TGA) were employed to character the molecular structures of β‐CD modified monomers and their copolymers. The swelling experiments indicate that the hydrogels with different equilibrium swelling ratio (ESR) possess obvious pH‐sensitivity and distinct dynamic swelling behavior. Using an anti‐cancer drug, chlorambucil (CHL), able to form complexes with β‐CD in water, as a model compound, the controlled drug release behaviors of these hydrogels were investigated. The release behavior of CHL from two kinds of hydrogels synthesized reveals that the release rate of CHL can be effectively controlled by pH values, cross‐linking density, and β‐CD content. In addition, it is found that the β‐CD with the proper frame and concentration can increase release efficiency of CHL from the hydrogels. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

11.
The objective of this study was to identify a kind of molecular imprinting polymer (MIP) which was suitable for recognizing naringin (NG) in aqueous medium. Based on two crosslinkers (hexamethylene diisocyanate and epichlorohydrin) and two polymerization methods (solution polymerization and emulsion polymerization), four non‐covalent naringin‐β‐cyclodextrine (NG‐β‐CD) imprinted polymers were prepared by using β‐CD as a functional monomer and NG as a template molecule. The binding property and selectivity were evaluated by equilibrium binding experiments. These demonstrated that all the sites in the MIPs show good selective binding ability for NG from naringin dihydrochalcone, a structurally similar molecule. Of the four MIPs, rod‐like 3# MIP which was prepared by emulsion polymerization using hexamethylene diisocyanate as crosslinker exhibited the highest selectivity, its imprinting factor α being 1.53. Scatchard analysis of 3# MIP suggests that there are two classes of binding sites during the MIP's recognition of NG. Additionally, the 3# MIP could be used at least five times without any loss in sorption capacity. Copyright © 2011 Society of Chemical Industry  相似文献   

12.
Polyaniline (PANI) salts doped with hydrochloric acid were prepared by using solid‐state polymerization in the presence of β‐cyclodextrin (β‐CD) at room temperature. The fourier transform infrared (FTIR) spectra, ultraviolet‐visible absorption spectra, X‐ray diffraction patterns were used to characterize the molecular structures of these polymers. Cyclic voltammetry study and conductivity measurements were done to investigate their electrochemical behaviors. The morphology of polymers was studied by the scanning electron microscopy and transmission electron microscopy. The results showed that PANI salts prepared in the presence of β‐CD had different physicochemical characteristics compared with PANI salt prepared in the absence of β‐CD. When the molar ratio of aniline to β‐CD was 80/20, the obtained PANI salt displayed higher crystallinity, conductivity and electrochemical properties. However, these properties were opposite on condition that the molar ratio of aniline to β‐CD was 50/50. The results also revealed that the morphology of PANI salt was affected by β‐CD, especially at aniline/β‐CD molar ratio in the feed of 50/50, in which PANI salt displayed rodlike structure morphology with a diameter of near 80–100 nm. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

13.
14.
Efficient one‐step syntheses of α,β‐ and β,β‐dihaloenones were achieved by ruthenium(II)‐catalyzed reactions between cyclic or acyclic diazodicarbonyl compounds and oxalyl chloride or oxalyl bromide in moderate to good yields. This methodology offers several significant advantages, which include ease of handling, mild reaction conditions, one‐step reaction, and the use of an effective and non‐toxic catalyst. The synthesized compounds were further transformed into highly functionalized novel molecules bearing aromatic rings on the enone moiety using the Suzuki reaction.

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15.
Two novel cyclodextrin‐modified anthraquinone dyes were synthesized and investigated for their complexation behaviour and formation of superstructures. Therefore, 1‐fluoro‐4‐N‐(propargylamino)anthraquinone and 1,4‐bis(propargyloxy)anthraquinone were prepared via nucleophilic aromatic displacement and subsequently covalently ‘click‐coupled’ in a copper(I)‐catalysed azide–alkyne cycloaddition with β‐cyclodextrin monoazide. Both the propargyl‐modified precursor and the click‐coupled anthraquinone dyes were evaluated as hosts and guests, respectively, in β‐cyclodextrin interactions. The anthraquinone dye bearing two cyclodextrins, 1,4‐bis((1‐β‐cyclodextrin‐1H‐1,2,3‐triazol‐5‐yl)methoxy)anthraquinone, enables the reversible formation of supramolecular crosslinked poly[(N,N‐dimethyl acrylamide)‐co‐(N‐(ferrocenoylmethyl)acrylamide)] ( 11 ), whereas the monofunctionalized compound 1‐fluoro‐4‐(((1‐β‐cyclodextrin‐1H‐1,2,3‐triazol‐5‐yl)methyl)amino)anthraquinone can be supramolecularly linked to 11 resulting in coloured polymers. These features of β‐cyclodextrin‐linked anthraquinone dyes can be verified with either 1H 1H NMR rotating frame nuclear Overhauser effect spectroscopy or the naked eye. © 2016 Society of Chemical Industry  相似文献   

16.
Water pollution problems pose a serious threat to the health of humans and other living organisms due to the increasing global contamination of various water resources by organic micropollutants, such as plastic components, dyes and pesticide intermediates. It has been a challenging problem to remove these organic micropollutants, despite various attempts. Here, we report a novel, cost‐effective and water‐insoluble crosslinked β‐cyclodextrin polymer for the efficient removal of various organic micropollutants from wastewaters with excellent adsorption capacity, large removal rate, robust performance and reusability. This polymer can remove 93% of bisphenol A within 1 min with an equilibrium uptake of 38 mg g?1 and a maximum adsorption capacity at equilibrium of 139 mg g?1. This is the fastest removal performance that has been reported so far, showing a bright future towards practical applications. © 2019 Society of Chemical Industry  相似文献   

17.
In this work, the pyromellitic dianhydride (PMDA)‐grafted β‐cyclodextrin (β‐CD) microspheres have been prepared for the removal of lead and cadmium metal ions in aqueous solution by a batch‐equilibration technique. The effects of the pH of the solution, contact time, and initial metal concentration were studied. The adsorption capacities for the two metal ions increase significantly as a large number of carboxyl groups are present on the microspheres surface. The equilibrium process is better described by the Langmuir isotherm than the Freundlich isotherm. The maximum adsorption capacities are 135.69 and 92.85 mg g?1 for Pb(II) and Cd(II), respectively. Kinetic studies show good correlation coefficients for a pseudosecond‐order kinetic model, confirming that the sorption rate is controlled by chemical adsorption. The regeneration of the adsorbent can be carried out by treating the loaded microspheres with 0.2 (mol L?1) HCl obtaining high desorption rate for the two metal ions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

18.
Because of low aqueous solubility and slow dissolution rate, cantharidin has a low oral bioavailability. Our research aims to prepare the inclusion complex of cantharidin and β‐cyclodextrin (β‐CD) and accomplish characterization, in vitro and in vivo evaluation. CA‐β‐CD inclusion complex was prepared by saturated solution method. The CA was demonstrated by HPLC in vitro experiment and by GC‐MS in vivo experiment. CA‐β‐CD inclusion complex was characterized by differential scanning calorimetry (DSC), X‐ray diffractometry (XRD), and nuclear magnetic resonance (NMR). Through complexation with β‐CD, the solubility of CA in neutral aqueous solution was improved significantly. CA‐β‐CD inclusion complex also shows a significantly improved dissolution rate in comparison with free CA. Comparison of the pharmacokinetics between CA‐β‐CD inclusion complex and free CA was performed in rats. The in vivo results show that CA‐β‐CD inclusion complex has earlier tmax, higher Cmax, and higher bioavailability than free CA after oral dosing. By comparing the AUC0–t of CA and CA‐β‐CD inclusion complex, the relative bioavailability of CA‐β‐CD inclusion complex to free CA was 506.3%, which highlighted the evidence of significantly improved bioavailability of formulation of CA with β‐CD. Thus, this β‐CD‐based drug delivery system should be an effective oral dosage form to improve oral bioavailability of CA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

19.
Nicotinic acetylcholine receptors (nAChRs) play an important role in many central nervous system disorders such as Alzheimer’s and Parkinson’s diseases, schizophrenia, and mood disorders. The α4β2 subtype has emerged as an important target for the early diagnosis and amelioration of Alzheimer’s disease symptoms. Herein we report a new class of α4β2 receptor ligands characterized by a basic pyrrolidine nucleus, the basicity of which was properly decreased through the insertion of a fluorine atom at the 3‐position, and a pyridine ring carrying at the 3‐position substituents known to positively affect affinity and selectivity toward the α4β2 subtype. Derivatives 3‐(((2S,4R)‐4‐fluoropyrrolidin‐2‐yl)methoxy)‐5‐(phenylethynyl)pyridine ( 11 ) and 3‐((4‐fluorophenyl)ethynyl)‐5‐(((2S,4R)‐4‐fluoropyrrolidin‐2‐yl)methoxy)pyridine ( 12 ) were found to be the most promising ligands identified in this study, showing good affinity and selectivity for the α4β2 subtype and physicochemical properties predictive of a relevant central nervous system penetration.  相似文献   

20.
In the present study the derivatization of two water‐soluble synthetic polymers, α,β‐poly(N‐2‐hydroxyethyl)‐DL ‐aspartamide (PHEA) and α,β‐polyasparthylhydrazide (PAHy), with glycidyltrimethylammonium chloride (GTA) is described. This reaction permits the introduction of positive charges in the macromolecular chains of PHEA and PAHy in order to make easier the electrostatic interaction with DNA. Different parameters affect the reaction of derivatization, such as GTA concentration and reaction time. PHEA reacts partially and slowly with GTA; on the contrary the reaction of PAHy with GTA is more rapid and extensive. The derivatization of PHEA and PAHy with GTA is a convenient method to introduce positive groups in their chains and it permits the preparation of interpolyelectrolyte complexes with DNA. © 2000 Society of Chemical Industry  相似文献   

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