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1.
When β‐cyclodextrin was adopted as a dye catcher, the degree of dye migration onto adjacent fabrics as well as onto the coated surface was greatly reduced, while other physical properties, such as waterproofness and breathability, remained unaffected. When acetylation of β‐cyclodextrin was carried out, its solubility in an organic solvent, including methyl ethyl ketone and toluene, was greatly improved. Hence, it provided a smoother coated surface and an excellent antimigration effect in a direct‐coating system. These results confirm that β‐cyclodextrin is an effective dye catcher in a polyurethane‐based coating system, in which it prevents the migration of the dyes from coated polyester fabrics onto adjacent surfaces. The solubility of cyclodextrin can be optimised by a chemical modification of its cyclodextrin‐hydroxyl groups. Hence, this host–guest interaction demonstrates a universal and effective platform for antimigration coating systems.  相似文献   

2.
Attachment of β‐cyclodextrin (β‐CD) molecules on cotton textile provides hosting cavities that can include a large variety of guest molecules for specific functionality. Five different new and existing techniques were evaluated for connecting β‐CD and its derivatives to cotton surface. A comparison has been made in terms of maximum attachment of β‐CD on cotton surface. Novel chemical based crosslinking with homo‐bi‐functional reactive dye (C.I. reactive black 5) and grafting with reactive monochlorotriazinyl‐β‐cyclodextrin show maximum attachment to cotton surface. Innovative, enzymatic coupling of especially synthesized 6‐monodeoxy‐6‐mono(N‐tyrosinyl)‐β‐cyclodextrin was performed on cotton textile surface. Enzymatic coupling was also carried out in a homogeneous system and attachment confirmed by UV–vis spectroscopy. This tyrosinase mediated coupling is low temperature and very specific technique. A phenolphthalein based analytical method was partially modified to reliably measure the amount of attached β‐CD on cotton surface. Atomic force microscopy and scanning electron microscopy techniques were used for surface characterization of the treated and untreated cotton surfaces. Alteration in surface topography has been observed for β‐CD treated samples. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

3.
Supramolecular assemblies with a bottle‐brush structure are obtained by inclusion complexation between β‐cyclodextrin and adamantane. β‐cyclodextrin‐modified chitosan is synthesized via the aldimine condensation reaction between β‐cyclodextrin monoaldehyde and chitosan as the host. The guest is prepared through the esterification reaction between methoxypoly(ethylene glycol) and 1‐adamantanecarboxylic acid chloride. The supramolecular assemblies are formed through the inclusion of adamantane‐modified methoxypoly(ethylene glycol) into the β‐cyclodextrin cavity on the chitosan chain. Fourier transform infrared and 1H NMR spectra were used to prove that the host, guest and assemblies were successfully obtained. UV?visible spectra were employed to confirm the formation of assemblies. Furthermore, the size of the particles in the assembled solution, the change before and after self‐assembly, and the effect of the addition of competitive molecules were studied by dynamic light scattering measurements. The results indicate that supramolecular assemblies have formed successfully which might be used to realize the biomimetic structure of the articular cartilage proteoglycan. © 2014 Society of Chemical Industry  相似文献   

4.
Concentrated inverse emulsion polymerization was used for making chromatography columns (based on crosslinked polystyrene divinylbenzene (PS‐DVB)) with pore sizes less than 10 μm. According to DSC‐thermal gravimetry thermograms, it was confirmed that the residual monomer concentration after polymerization process is negligible. For application of these columns in chiral chromatography, the β‐cyclodextrin is chemically fixed on the PS‐DVB resin pore surface. The presence of hydroxyl groups in the PS‐DVB resin after chemical modification was confirmed by FTIR spectroscopy. By chemical modification of the PS‐DVB resin, thermal stability increased up to 446°C. The structure of columns was analyzed by scanning electron microscopy (SEM). SEM evaluations showed that the porous structure of PS‐DVB resin was maintained intact after the chemical modification with β‐cyclodextrin. According to X‐ray data, presence of the crystalline domain that is related to β‐cyclodextrin is confirmed.© 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 857–863, 2006  相似文献   

5.
A new triphenylphosphane based on a β‐cyclodextrin skeleton (PM‐β‐CD‐OTPP) was synthesized. This ligand can be dispersed in water by using the nanoprecipitation method. Transmission electron microscopy and NMR spectroscopy showed that PM‐β‐CD‐OTPP is aggregated in water and forms a stable dispersion. Its aqueous solubility can be dramatically increased in the presence of selected water‐soluble guests by formation of inclusion complexes. Associated to a rhodium precursor, PM‐β‐CD‐OTPP is able to generate soluble rhodium species in water. In addition, NMR experiments showed that the cyclodextrin cavity remains accessible for a guest even when PM‐β‐CD‐OTPP is coordinated to rhodium. Finally, this ligand was efficient for rhodium‐catalyzed hydrogenation and hydroformylation performed in aqueous medium.  相似文献   

6.
Hydrophobically modified chitosan containing β‐cyclodextrin (CD) units was synthesized by using tosylated β‐CD. The final product was characterized by Fourier transform infrared (FTIR) spectroscopy, elemental analysis and TGA, and rheometry. The polymer bearing β‐CD moieties was used to obtain crosslinked microparticles by spray‐drying which could then be used in a controlled release system for drugs. FTIR confirmed the formation of an amide linkage between cyclodextrin and chitosan. As fluorescence spectroscopy demonstrated, hydrophobic microenvironments were formed by chitosan bearing cyclodextrin in solution at lower concentrations than for chitosan. Rheometry and FTIR showed the crosslinking of the new polymer using genipin, a molecule of natural origin. Microspheres (MS) obtained by spray‐drying showed narrow size distribution when β‐CD was grafted onto chitosan and ξ‐potential of MS was slightly lower although it remained positive. In conclusion, β‐CD linked chitosan polymer can be considered as a very promising controlled drug delivery system for drugs. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

7.
Surfactant adsorption onto solid surfaces is problematic in some industrial processes, such as in surfactant flooding for enhanced oil recovery. In this work, it was hypothesized that the use of a surfactant delivery system could prevent surfactant adsorption onto solid surfaces. Therefore, the encapsulation of sodium dodecyl sulfate (SDS) into the hydrophobic core of β‐cyclodextrin (β‐CD) to generate a surfactant delivery system (SDS/β‐CD) was evaluated in this work. This complexation was characterized using optical and scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT‐IR). Dynamic adsorption evaluation was applied to determine the effectiveness of the complexation in inhibiting surfactant adsorption onto a variety of solid adsorbents including sand, and mixtures of sand–kaolin and sand–shale. Surfactant adsorption was also evaluated applying the quartz crystal microbalance technology (QCM‐D). The formation and morphology of the complexation was confirmed by optical microscopy, SEM, and FT‐IR. Dynamic adsorption tests demonstrated the effectiveness of the surfactant delivery approach in preventing the adsorption of surfactant (up to 74 % adsorption reduction). The QCM‐D technology confirmed these observations. Several mechanisms were proposed to explain the inhibition of surfactant adsorption including steric hindrance, self‐association of inclusion complexes, hydrophilicity increase, and disruption of hemimicelles formation.  相似文献   

8.
Porous silica beads were coated with a crosslinked β‐cyclodextrin polymer by in situ polymerization/crosslinking of 2‐hydroxypropyl β‐cyclodextrin with 1,6‐hexamethylenediisocyanate in anhydrous dimethylsulfoxide. This method was developed for the preparation of reversed‐phase high performance liquid chromatography stationary phases. The mass of polymer immobilized onto the silica surface was controlled by the amount of coupling agent, 1,6‐hexamethylenediisocyanate, added during the coating process. The influence of the polymer coating on the physical features of the beads was investigated by means of nitrogen adsorption/desorption methods, scanning electron microscopy and energy dispersion X‐ray analysis. The column lifetime was found to be primarily dependent on the extent of crosslinking of the stationary phase. Moreover, it was demonstrated that the synthesis of highly crosslinked stationary phases with a reasonable column lifetime gave rise to a phase separation of the β‐cyclodextrin polymer. To prove their usefulness as reversed‐phase packing materials, they were used to separate mixtures of nitrophenol positional isomers, four pesticides, and drugs. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1419–1426, 2004  相似文献   

9.
It has been demonstrated that surfaces coated with poly(ethylene glycol) (PEG) are capable of reducing protein adsorption, bacterial attachment, and biofilm formation. In this communication cold‐plasma–enhanced processes were employed for the deposition of PEG‐like structures onto stainless steel surfaces. Stainless steel samples were coated under 1,4,7,10‐tetraoxacyclododecane (12‐crown‐4)–ether and tri(ethylene glycol) dimethyl ether (triglyme)–radio frequency (RF)–plasma conditions. The chemistry and characteristics of plasma‐coated samples and biofilms were investigated using electron spectroscopy for chemical analysis (ESCA), atomic force microscopy (AFM), and water contact angle analysis. ESCA analysis indicated that the plasma modification resulted in the deposition of PEG‐like structures, built up mainly of –CH2? CH2? O– linkages. Plasma‐coated stainless steel surfaces were more hydrophilic and had lower surface roughness values compared to those of unmodified substrates. Compared to the unmodified surfaces, they not only significantly reduced bacterial attachment and biofilm formation in the presence of a mixed culture of Salmonella typhimurium, Staphylococcus epidermidis, and Pseudomonas fluorescens but also influenced the chemical characteristics of the biofilm. Thus, plasma deposition of PEG‐like structures will be of use to the food‐processing and medical industries searching for new technologies to reduce bacterial contamination. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3425–3438, 2001  相似文献   

10.
The natural antibacterial agent allyl isothiocyanate (AITC) encapsulated in either α‐ or β‐cyclodextrin (CD) has previously been evaluated as a slow‐release additive in polylactide‐co‐polycaprolactone (PLA–PCL) films designed for use in cheese packaging. In the research described in this article, thermogravimetric analysis (TGA) and thermogravimetric analysis in tandem with mass spectrometry (TGA–MS) were used to explore the thermal properties of CD‐encapsulated AITC complexes as well as those of PLA–PCL films containing these complexes. To our knowledge, this is the first reported application of the TGA–MS technique to explore the thermal stability of CD‐entrapped AITC and the first study to report differences in thermal stability of AITC in α‐and β‐CD cavities in the solid state. Observed differences in the thermal degradation profile of films containing the CD complexes can be explained if AITC binds more strongly to β‐CD than to α‐CD. This hypothesis has been reinforced by gas chromatography (GC) and high performance liquid chromatography (HPLC) studies, the results of which suggest that a new covalently bound AITC–CD complex may be formed when incorporating the β‐CD complex of AITC in PLA–PCL films but not when incorporating the α‐CD complex of AITC. This finding means that the α‐CD complex of AITC would be preferred in situations where adequate long‐term controlled release of AITC from polymer films is required, as for example in the case of active packaging applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

11.
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   

12.
Polymer‐cyclodextrin (CD) composite nanofibers, by virtue of the hollow cavities and abundant hydroxyl groups present in CDs, have tremendous potential in a variety of biomedical applications. However, in most cases, especially in aliphatic polyesters, polymer chains thread readily into CD cavities, therefore its potential has not yet been fully realized. Herein, we report the formation of poly(ε‐caprolactone) (PCL)/β‐CD functional nanofibers by electrospinning their mixture from chloroform/N,N‐dimethylformamide (60 : 40). The fiber diameters of the neat PCL and β‐CD functionalized fibers were measured from the images obtained from a scanning electron microscope and were found to be about 500 nm. The efficiency of wound odor absorbance by these composite fibers was studied using a simulated wound odor solution, consisting of butyric and propionic acids in ethanol. Immersion tests indicated that even under less than ideal test conditions, the nanofibers containing β‐CDs were very efficient in masking the odor. The odor masking capability of the β‐CD functionalized PCL nanofibers were further confirmed by thermogravimetric analyses and GC observations, with the former method showing unique degradation patterns. The PCL/β‐CD nanocomposites, by virtue of having their β‐CD cavities free and unthreaded by PCL, could potentially be an ideal substrate for removing wound odors through formation of inclusion compounds with odorants, while providing an ideal environment for the wound to heal. These results suggest tailoring polymer‐CD nanostructures for specific applications in wound odor absorbance, surface grafting of chemical moieties, and vehicles for drug delivery, as examples. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42782.  相似文献   

13.
Cyclodextrins (CD) are produced from starch by the action of cyclodextrin glycosyltransferase (CGTase) enzyme. Structurally, cyclodextrins consist of 6, 7, or 8 (α, β, and γ cyclodextrins, respectively) D‐glucopyranosyl units connected by α‐(1,4) glycosidic linkages. Having polar and hydrophilic outer sides and hydrophobic cavitation gives cyclodextrins a chance to form inclusion complexes with dyes in hydrophilic mediums. In this research, the equalizing effect of β‐cyclodextrins in dyeing of polyamide 6,6 woven fabrics with 6 different acid dyes were investigated. From the experimental results, it was determined that the β‐cyclodextrin shows a retarding and equalizing effect in dyeings carried out with the dyes that show interaction with β‐CD. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2660–2668, 2007  相似文献   

14.
BACKGROUND: Endocrine disruptors in the aquatic environment and their potential adverse effects are currently issues of concern. One of these endocrine disruptors is 2,2‐bis(4‐hydroxy‐3‐methylphenyl)propane (BPP). In this work the molecular recognition interaction of BPP with β‐cyclodextrin (β‐CD) was studied using IR spectroscopy and steady state fluorescence spectroscopy, and the photocatalytic degradation behaviour of BPP based on molecular recognition interaction was investigated in a TiO2/UV–visible (λmax = 365 nm) system. This might provide a new method for the treatment of some organic pollutants in wastewater. RESULTS: β‐CD reacts with BPP to form a 1:1 inclusion complex, the formation constant of which is 4.94 × 103 L mol?1. The photodegradation rate constant of BPP after molecular recognition by β‐CD showed a 1.42‐fold increase in the TiO2/UV–visible (λmax = 365 nm) system. The photodegradation of BPP depended on the concentration of β‐CD, the pH value, the gaseous medium and the initial concentration of BPP. The photodegradation efficiency of BPP with molecular recognition was higher than that without molecular recognition. After 100 min of irradiation the mineralisation efficiency of BPP after molecular recognition by β‐CD reached 94.8%, whereas the mineralisation efficiency of BPP before molecular recognition by β‐CD was only 40.6%. CONCLUSION: The photocatalytic degradation of BPP after molecular recognition by β‐CD can be enhanced in the TiO2/UV‐visible (λmax = 365 nm) system. This enhancement is dependent on the enhancement of the adsorption of BPP, the moderate inclusion depth of BPP in the β‐CD cavity and the increase in the frontier electron density of BPP after molecular recognition. Copyright © 2008 Society of Chemical Industry  相似文献   

15.
The inclusion complex formed by β‐cyclodextrin (β‐CD) with the cationic surfactant hexadecyltrimethylammonium chloride (HTAC) was studied by viscometry using poly(ethylene oxide) (PEO)–HTAC aggregates as a viscosity indicator. The relative viscosity of β‐CD in aqueous PEO–HTAC solution profiles shows that the formation of the β‐CD/HTAC inclusion complex causes HTAC molecules to be stripped off the PEO chains, resulting in a decrease of aqueous solution viscosity as a result of the decrease in electrostatic repulsion between polymer‐bound HTAC micelles. The viscosity minimum at Cβ‐CD/CHTAC = 0.5 indicates that the molecular ratio of host molecule to guest molecule is 1:2 in the β‐CD/HTAC inclusion complex.  相似文献   

16.
Cyclodextrins are cyclic oligosaccharides. Cyclodextrin molecules can form inclusion complexes with a large number of organic molecules. The properties of cyclodextrins enable them to be used in a variety of different textile applications. Cyclodextrins can act as auxiliaries in washing and dyeing processes, and they can also be fixed onto different fiber surfaces. Because of the complexing abilities of cyclodextrins, textiles with new functional properties can be prepared. Poly(carboxylic acid)s such as 1,2,3,4‐butane tetracarboxylic acid (BTCA) are well‐known non‐formaldehyde crosslinking reagents. BTCA has four carboxylic acid groups, which can react with hydroxyl groups of cellulose and form stable ester bonds. We crosslinked β‐cyclodextrin molecules on hydroxyl groups of cellulose via BTCA. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1323–1328, 2005  相似文献   

17.
The poly(ethylene glycol) (PEG)‐grafted styrene (St) copolymer, which was formed as a nanosphere, was used as an agent to modify the surface of poly(ethylene terephthalate) (PET) film. The graft copolymer was dissolved into chloroform and coated onto the PET film by dip–coating method. The coated amount depends on the content ratios of PEG and St, the solution concentration, and the coating cycles. The graft copolymers having a low molecular weight of PEG‐ or St‐rich content was fairly stable on washing in sodium dodecyl sulfate (SDS) aqueous solution. It was confirmed that the PET surface easily altered its surface property by the coating of the graft copolymers. The contact angles of the films coated with the graft copolymers were very high (ca. 105–120°). The coated film has good antistatic electric property, which agreed with PEG content. The best condition of coating is a one‐cycle coating of 1% (w/v) graft copolymer solution. The coated surface had water‐repellency and antistatic electric property at the same time. The graft copolymer consisted of a PEG macromonomer; St was successfully coated onto PET surfaces, and the desirable properties of both of PEG macromonomer and PSt were exhibited as a novel function of the coated PE film. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1524–1530, 1999  相似文献   

18.
Chitosan‐graft‐β‐cyclodextrin (CS‐g‐β‐CD) copolymer was synthesized by conjugating β‐cyclodextrins to chitosan molecules through click chemistry. The copolymer structure was characterized by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). CS‐g‐β‐CD/CMC nanoparticles were prepared by a polyelectrolyte complexation process in aqueous solution between CS‐g‐β‐CD copolymer and carboxymethyl chitosan (CMC), which was used to load anticancer drug (Doxorubicin hydrochloride, DOX·HCl) with hydrophobic group. The particle size, surface charge, zeta potential, and morphology of the nanoparticles were characterized with dynamic light scattering. The drug loading efficiency and in vitro release of DOX·HCl of the nanoparticles were measured by ultraviolet spectrophotometer. The results demonstrated that the size, surface charge and drug loading efficiency of the nanoparticles could be modulated by the fabrication conditions. The drug loading efficiency of CS‐g‐β‐CD/CMC nanoparticles was improved from 52.7% to 88.1% because of the presence of β‐CD moieties with hydrophobic cavities, which can form inclusion complexes with the drug molecules. The in vitro release results showed that the CS‐g‐β‐CD/CMC nanoparticles released DOX·HCl in a controlled manner, importantly overcoming the initial burst effect. These nanoparticles possess much potential to be developed as anticancer drug delivery systems, especially those drugs with hydrophobic group. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41034.  相似文献   

19.
Based on a combination of poly(N‐isopropylacrylamide), which could respond to an external temperature, and β‐cyclodextrin (β‐CD), which could form a molecular inclusion complex, a novel hydrogel, having both thermal and pH sensitivities and containing β‐CD and N‐isopropylacrylamide (NIPA) segments, was synthesized. For the incorporation of β‐CD into the polymer network, a macromonomer was prepared first by the reaction of a β‐CD‐based polymer with maleic anhydride in dimethylformamide and then by copolymerization with NIPA in an aqueous solution. Elemental analysis, IR spectroscopy, differential scanning calorimetry, and swelling measurements were employed for the characterization of the hydrogel chain structure and its physical properties. With methyl orange as a model compound in inclusion tests, it was found that the hydrogel not only possessed a remarkable supramolecular inclusion ability (with respect to that of the small molecule cyclodextrin) but also could sensitively respond to various external stimuli, including the temperature, pH, and ionic strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 361–367, 2003  相似文献   

20.
A novel selective separation method for organic compounds, especially thermosensitive substances, has been proposed using unsubstituted β‐cyclodextrin (β‐CD) as a host and some alcohols and aldehydes as model guests in aqueous solution. The separation factors were evaluated from the extraction of an equimolar mixture of alcohol and aldehyde compounds. The inclusion equilibrium constants for several alcohols and aldehydes over β‐CD have been calculated through their UV‐vis spectra. The Gibbs free energy changes of β‐CD/substrates complexes (ΔG) have been calculated combined B3LYP/6‐31G(d)//ONIOM2(B3LYP/6‐31G(d):PM3) with semicontinuum solvation model. The difference of Gibbs free energy changes (ΔΔG) for the inclusion complexes formed via the intermolecular weak interactions e.g., hydrogen bond and electrostatic interaction was the reason why alcohol and aldehyde compounds could be selectively separated. © 2010 American Institute of Chemical Engineers AIChE J, 2011  相似文献   

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