Styrene-butadiene-styrene (SBS) modified bitumen crack filling material with organophilic montmorillonite (OCFM) was prepared by melt blending. X-ray diffraction analysis shows that the interlayer spacing of organ...Styrene-butadiene-styrene (SBS) modified bitumen crack filling material with organophilic montmorillonite (OCFM) was prepared by melt blending. X-ray diffraction analysis shows that the interlayer spacing of organophilic montmorillonite (OMMT) in OCFM is widened and an exfoliated structure may be formed. Thermal-oxidative aging behavior of OCFM and SBS modified bitumen crack filling material (SCFM) was investigated. The experimental results indicate that the rate of thermal-oxidative aging of OCFM is much slower than that of SCFM, which can be attributed to barrier of exfoliated structure of OCFM to oxygen.展开更多
The adsorptive removal of antimony (III) has been successfully obtained on montmorillonite (MMT) and modified MMT from synthetic solution. The adsorption behavior of the modified and unmodified MMT has been investigat...The adsorptive removal of antimony (III) has been successfully obtained on montmorillonite (MMT) and modified MMT from synthetic solution. The adsorption behavior of the modified and unmodified MMT has been investigated as a function of initial concentration of metal ion in the solution, pH of the solution and contact time using a batch extraction process. The optimized process can be applied for the adsorption, detection and estimation of antimony from 0.006 μg/ml (6.0 ppb) to 100.00 μg/ml (100.0 ppm) in aqueous solution. It has been observed that almost 99% of antimony (III) can be successfully extracted from a solution containing 100 μg/ml of the metal ion at pH 6.0 at 25?C ± 2?C. The investigation of the kinetics of sorption of antimony (III) on MMT/modified MMTshows intraparticle diffusion to be the rate limiting step during the initial stages of adsorption followed by chemisorption.展开更多
In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT conte...In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT content on properties of CRMA were studied.The rutting factor obtained by dynamic shear rheological(DSR)test was adopted to evaluate the high-temperature performance.The creep stiffness and m value determined by the bending beam rheometer(BBR)test were employed to evaluate the low-temperature performance.The softening point,ductility,rutting factor before and after rolling thin film ovens test(RTFOT)and pressure aging vessel test(PAV)were compared to characterize the aging properties.Moreover,the segregation test after being reserved for 48 h and 7 d was conducted,and the softening point and rutting factor of upper and lower layers of segregation pipe were adopted to evaluate the storage stability.The results indicated that the high-temperature performance and anti-aging performance were developed with the increasing content of OMMT,while the low-temperature performance deteriorated.The storage stability was improved with the increasing content of OMMT before the content exceeded 4%,after which the storage stability declined.Taking account of all factors,it is suggested that the optimum content of OMMT is 3%−4%.展开更多
The aim of the current study was to prepare organo-modified nano montmorillonite (OMNM) and to evaluate its chemopreventive effects against the hapatonephrotoxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OA)...The aim of the current study was to prepare organo-modified nano montmorillonite (OMNM) and to evaluate its chemopreventive effects against the hapatonephrotoxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OA) singly or in combination in rats. OMNM was prepared using Cetyltrimethylammoniumbromide (CTAB) as organic modifier. Eighty male Sprague Dawley were divided into 8 groups and treated for 8 weeks as follow: the control group;the group treated orally with AFB1 (80 μg/kg b.w.);the group treated with OA (100 μg/kg b.w.);the group treated with AFB1 plus OA, the group treated with OMNM (5 g/kg diet) and the groups treated with AFB1 and/or OA plus OMNM. At the end of treatment period, blood and tissue samples were collected from all animals for biochemical and histological analysis. The results revealed that the expansion in the basal spacing of the montmorillonite due to the intercalation of CTAB was 7.20?Å and the average particle size of OMNM was 120 nm. The in vivo results indicated that treatment with both AFB1 and OA singly or in combination resulted in a significant increase in liver and kidney function parameters, oxidative stress and tumor markers accompanied with a significant decrease in antioxidant enzyme activities and significant histological changes in liver and kidney tissues. These changes were severe in the group received the combined treatment of AFB1 and OA. OMNM alone did not show any toxic effect and it succeeded to prevent or at least diminish the toxic effects and the histological changes in liver and kidney. It can be concluded that treatment with AFB1 and OA has a synergistic toxic effects and OMNM is safe and it is a promise candidate as an additive to protect against the exposure to multi-mycotoxins in high risk population.展开更多
Poly (vinyl chloride)/ethylene-vinyl acetate/montmorillonite (PVC/EVA/OMMT) composites were prepared by melt blending method. Two kinds of montmorillonites were organically modified by trimethyloctadecyl ammonium and ...Poly (vinyl chloride)/ethylene-vinyl acetate/montmorillonite (PVC/EVA/OMMT) composites were prepared by melt blending method. Two kinds of montmorillonites were organically modified by trimethyloctadecyl ammonium and dimethyl bis (hydrogenated tallow) ammonium, respectively. The morphology and tensile properties of the resultant composites were discussed in terms of the modifier type and OMMT content. The PVC/EVA/OMMT composites have intercalated structure, which is independent of the polarity of the modifiers, while the tensile properties show strong dependence on the modifier type. The OMMT modified by polar modifier gives higher tensile ductile and strength of PVC/EVA/OMMT composites.展开更多
Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepar...Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction(XRD), fourier transformed infrared spectroscopy(FTIR) and transmission electron microscopy(TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results: In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria(Escherichia coli), gram-positive bacteria(Staphylococcus aureus), fungi(Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions: The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.展开更多
Unsaturated polyester resin (UPR)/acrylate-terminated polyurethane (ATPU)/organo-modified montmorillonite (OMMT) nanocomposites were prepared by the in situ intercalative polymerization method. Samples were prep...Unsaturated polyester resin (UPR)/acrylate-terminated polyurethane (ATPU)/organo-modified montmorillonite (OMMT) nanocomposites were prepared by the in situ intercalative polymerization method. Samples were prepared by the sequential mixing, i.e. mixture of the ATPU and styrene (S) and OMMT were prepared in the first step; UPR was then added to the pre-intercalates of ATPU/S/OMMT. Results indicate that the mechanical properties and thermal properties of UPR/ATPU/OMMT nanocomposites greatly depend on the amount of ATPU and OMMT. Results show that the addition of ATPU could increase the impact strength of UPR/ATPU composites, but the tensile strength, flexural strength and heat resistance of the materials are obviously decreased. When the weight ratio between UPR, ATPU and OMMT were 82:15:3, the impact strength and heat distortion-temperature of nanocomposite were greatly improved, meanwhile there was little change for other properties of the nanocomposites. The synergistic enhancement effects of ATPU and OMMT on the composites were observed. The structures and morphology of the composites were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy.展开更多
Different composites of organomodified montmorillonite(OMMT)/bitumen were prepared by melt blending with hexadecyl dimethyl benzyl ammonium modified montmorillonite(HBM) and double octadecyl dimethyl ammonium modified...Different composites of organomodified montmorillonite(OMMT)/bitumen were prepared by melt blending with hexadecyl dimethyl benzyl ammonium modified montmorillonite(HBM) and double octadecyl dimethyl ammonium modified montmorillonite(DOM).The structures of two kinds of montmorillonite modified bitumen were characterized by X-ray diffraction(XRD).The effects of different montmorillonites on the dynamic rheological properties of the modified bitumens were investigated by dynamic shear rheometer(DSR).The XRD results show that DOM modified bitumen forms an intercalated structure,whereas the HBM modified bitumen forms an exfoliated structure.DSR results indicate that OMMT modified bitumens exhibit higher complex modulus,lower phase angle than pristine bitumen,which means that the resistance to rutting at high temperatures of pristine bitumen is improved due to the introduction of OMMT.Compared with DOM modified bitumen,HBM modified bitumen shows better rutting resistance,which is contributed to the formation of exfoliated structure in HBM modified bitumen.展开更多
Nanocomposite membranes containing poly(m-phenylene isophthalamide)(PMIA) and organically modified montmorillonite(OMMT) were prepared by a combination of solution dispersion and wet-phase inversion methods, and...Nanocomposite membranes containing poly(m-phenylene isophthalamide)(PMIA) and organically modified montmorillonite(OMMT) were prepared by a combination of solution dispersion and wet-phase inversion methods, and the effects of OMMT addition on the properties and performance of fabricated nanofiltration membranes were investigated. The membranes were characterized by contact angle measurements, scanning electron microscopy(SEM), atomic force microscopy(AFM), thermogravimetric analysis, and zeta potential.The performance of the membranes was elucidated by the removal of perfluorooctane sulfonate(PFOS) at neutral p H. Increasing OMMT concentration improved the thermal stability and hydrophilicity of the membranes. The permeation and rejection of PFOS were significantly improved. The performance of fabricated nanofiltration membranes in removal of PFOS varied depending on the solute and membrane properties as well as solution conditions. Finally,a comparison between fabricated membranes and a commercial NF membrane(ESNA1-K1,Hydecanme) proved that the OMMT addition is a convenient procedure for producing nanocomposite membranes with superior properties and performance.展开更多
基金Funded by the National Natural Science Foundation of China (50773061)
文摘Styrene-butadiene-styrene (SBS) modified bitumen crack filling material with organophilic montmorillonite (OCFM) was prepared by melt blending. X-ray diffraction analysis shows that the interlayer spacing of organophilic montmorillonite (OMMT) in OCFM is widened and an exfoliated structure may be formed. Thermal-oxidative aging behavior of OCFM and SBS modified bitumen crack filling material (SCFM) was investigated. The experimental results indicate that the rate of thermal-oxidative aging of OCFM is much slower than that of SCFM, which can be attributed to barrier of exfoliated structure of OCFM to oxygen.
文摘The adsorptive removal of antimony (III) has been successfully obtained on montmorillonite (MMT) and modified MMT from synthetic solution. The adsorption behavior of the modified and unmodified MMT has been investigated as a function of initial concentration of metal ion in the solution, pH of the solution and contact time using a batch extraction process. The optimized process can be applied for the adsorption, detection and estimation of antimony from 0.006 μg/ml (6.0 ppb) to 100.00 μg/ml (100.0 ppm) in aqueous solution. It has been observed that almost 99% of antimony (III) can be successfully extracted from a solution containing 100 μg/ml of the metal ion at pH 6.0 at 25?C ± 2?C. The investigation of the kinetics of sorption of antimony (III) on MMT/modified MMTshows intraparticle diffusion to be the rate limiting step during the initial stages of adsorption followed by chemisorption.
基金Projects(51838001,51878070,51908069)supported by the National Natural Science Foundation of China。
文摘In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT content on properties of CRMA were studied.The rutting factor obtained by dynamic shear rheological(DSR)test was adopted to evaluate the high-temperature performance.The creep stiffness and m value determined by the bending beam rheometer(BBR)test were employed to evaluate the low-temperature performance.The softening point,ductility,rutting factor before and after rolling thin film ovens test(RTFOT)and pressure aging vessel test(PAV)were compared to characterize the aging properties.Moreover,the segregation test after being reserved for 48 h and 7 d was conducted,and the softening point and rutting factor of upper and lower layers of segregation pipe were adopted to evaluate the storage stability.The results indicated that the high-temperature performance and anti-aging performance were developed with the increasing content of OMMT,while the low-temperature performance deteriorated.The storage stability was improved with the increasing content of OMMT before the content exceeded 4%,after which the storage stability declined.Taking account of all factors,it is suggested that the optimum content of OMMT is 3%−4%.
文摘The aim of the current study was to prepare organo-modified nano montmorillonite (OMNM) and to evaluate its chemopreventive effects against the hapatonephrotoxicity induced by aflatoxin B1 (AFB1) and ochratoxin A (OA) singly or in combination in rats. OMNM was prepared using Cetyltrimethylammoniumbromide (CTAB) as organic modifier. Eighty male Sprague Dawley were divided into 8 groups and treated for 8 weeks as follow: the control group;the group treated orally with AFB1 (80 μg/kg b.w.);the group treated with OA (100 μg/kg b.w.);the group treated with AFB1 plus OA, the group treated with OMNM (5 g/kg diet) and the groups treated with AFB1 and/or OA plus OMNM. At the end of treatment period, blood and tissue samples were collected from all animals for biochemical and histological analysis. The results revealed that the expansion in the basal spacing of the montmorillonite due to the intercalation of CTAB was 7.20?Å and the average particle size of OMNM was 120 nm. The in vivo results indicated that treatment with both AFB1 and OA singly or in combination resulted in a significant increase in liver and kidney function parameters, oxidative stress and tumor markers accompanied with a significant decrease in antioxidant enzyme activities and significant histological changes in liver and kidney tissues. These changes were severe in the group received the combined treatment of AFB1 and OA. OMNM alone did not show any toxic effect and it succeeded to prevent or at least diminish the toxic effects and the histological changes in liver and kidney. It can be concluded that treatment with AFB1 and OA has a synergistic toxic effects and OMNM is safe and it is a promise candidate as an additive to protect against the exposure to multi-mycotoxins in high risk population.
文摘Poly (vinyl chloride)/ethylene-vinyl acetate/montmorillonite (PVC/EVA/OMMT) composites were prepared by melt blending method. Two kinds of montmorillonites were organically modified by trimethyloctadecyl ammonium and dimethyl bis (hydrogenated tallow) ammonium, respectively. The morphology and tensile properties of the resultant composites were discussed in terms of the modifier type and OMMT content. The PVC/EVA/OMMT composites have intercalated structure, which is independent of the polarity of the modifiers, while the tensile properties show strong dependence on the modifier type. The OMMT modified by polar modifier gives higher tensile ductile and strength of PVC/EVA/OMMT composites.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201403047)Science Technology Department of Zhejiang Province(2015C02022)
文摘Background: A series of modified montmorillonites(Mt) including zinc-loaded Mt(Zn-Mt), copper-loaded Mt(Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio(Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction(XRD), fourier transformed infrared spectroscopy(FTIR) and transmission electron microscopy(TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.Results: In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria(Escherichia coli), gram-positive bacteria(Staphylococcus aureus), fungi(Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.Conclusions: The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.
基金This research was supported by the Science and Technology Key Project of Guangdong(A1070203).
文摘Unsaturated polyester resin (UPR)/acrylate-terminated polyurethane (ATPU)/organo-modified montmorillonite (OMMT) nanocomposites were prepared by the in situ intercalative polymerization method. Samples were prepared by the sequential mixing, i.e. mixture of the ATPU and styrene (S) and OMMT were prepared in the first step; UPR was then added to the pre-intercalates of ATPU/S/OMMT. Results indicate that the mechanical properties and thermal properties of UPR/ATPU/OMMT nanocomposites greatly depend on the amount of ATPU and OMMT. Results show that the addition of ATPU could increase the impact strength of UPR/ATPU composites, but the tensile strength, flexural strength and heat resistance of the materials are obviously decreased. When the weight ratio between UPR, ATPU and OMMT were 82:15:3, the impact strength and heat distortion-temperature of nanocomposite were greatly improved, meanwhile there was little change for other properties of the nanocomposites. The synergistic enhancement effects of ATPU and OMMT on the composites were observed. The structures and morphology of the composites were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy.
基金Projects(50773061) Funded by the National Natural Science Foundation of China
文摘Different composites of organomodified montmorillonite(OMMT)/bitumen were prepared by melt blending with hexadecyl dimethyl benzyl ammonium modified montmorillonite(HBM) and double octadecyl dimethyl ammonium modified montmorillonite(DOM).The structures of two kinds of montmorillonite modified bitumen were characterized by X-ray diffraction(XRD).The effects of different montmorillonites on the dynamic rheological properties of the modified bitumens were investigated by dynamic shear rheometer(DSR).The XRD results show that DOM modified bitumen forms an intercalated structure,whereas the HBM modified bitumen forms an exfoliated structure.DSR results indicate that OMMT modified bitumens exhibit higher complex modulus,lower phase angle than pristine bitumen,which means that the resistance to rutting at high temperatures of pristine bitumen is improved due to the introduction of OMMT.Compared with DOM modified bitumen,HBM modified bitumen shows better rutting resistance,which is contributed to the formation of exfoliated structure in HBM modified bitumen.
基金financially supported by the National Natural Science Foundation of China(Nos.21176245,21476248)the National Science and Technology Support Program of China(Nos.2012BAJ25B02,2012BAJ25B06)the special fund of the State Key Joint Laboratory of Environment Simulation and Pollution Control(No.12L02ESPC)
文摘Nanocomposite membranes containing poly(m-phenylene isophthalamide)(PMIA) and organically modified montmorillonite(OMMT) were prepared by a combination of solution dispersion and wet-phase inversion methods, and the effects of OMMT addition on the properties and performance of fabricated nanofiltration membranes were investigated. The membranes were characterized by contact angle measurements, scanning electron microscopy(SEM), atomic force microscopy(AFM), thermogravimetric analysis, and zeta potential.The performance of the membranes was elucidated by the removal of perfluorooctane sulfonate(PFOS) at neutral p H. Increasing OMMT concentration improved the thermal stability and hydrophilicity of the membranes. The permeation and rejection of PFOS were significantly improved. The performance of fabricated nanofiltration membranes in removal of PFOS varied depending on the solute and membrane properties as well as solution conditions. Finally,a comparison between fabricated membranes and a commercial NF membrane(ESNA1-K1,Hydecanme) proved that the OMMT addition is a convenient procedure for producing nanocomposite membranes with superior properties and performance.