Studying new wood composites through nano science and technology (NSC) will develop new compounding theory of wood, and accelerate the combination of new technology, wood science, material science and other discipline...Studying new wood composites through nano science and technology (NSC) will develop new compounding theory of wood, and accelerate the combination of new technology, wood science, material science and other disciplines. The compounding of wood and inorganic MMT on nanoscale molecular level has high potential to greatly improve the mechanical properties, fire retardance, abrasion resistance, decay resistance, dimensional stability and other properties of wood. Based on the great achievements of polymer/montmorillonite (MMT) nanocomposites, this paper reviewed nano intercalation compounding methods (i.e. in-situ intercalative polymerization and direct polymer intercalation), and discussed the structure, properties and modification of montmorillonite (MMT). According to the main chemical components and particular structure of wood, the authors discussed the liquefaction and plasticization of wood, compared the dissolvability and meltability between wood and polymer, and then systematically put forward the basic idea, technological processes and schematic diagram to prepare wood/MMT nanocomposites (WMNC). The key technology to prepare WMNC is either to introduce delaminated MMT nanolayers into wood with the help of some intermediate polymers, or to obtain liquefied wood or plasticized wood from the complicated natural composite. It is applicable and effective to realize wood/MMT nanoscale compounding with the help of proper intercalation agent and medium polymer through the proposed 搊ne-step?or 搕wo-step?impregnating processes.展开更多
For this study, an intercalation compounding method was used to prepare Chinese fir wood/Ca-montmorillonite （Ca-MMT） composite board to improve its properties such as surface mechanical properties, flame retardance ...For this study, an intercalation compounding method was used to prepare Chinese fir wood/Ca-montmorillonite （Ca-MMT） composite board to improve its properties such as surface mechanical properties, flame retardance and dimensional stability. By virtue of water-soluble phenolic resin （PF）, Chinese fir wood and Ca-MMT were mixed by pressure and vacuum impregnation. The optimum impregnation technology of Chinese fir wood/Ca-MMT composite board was obtained by using an orthogonal design and a single factor design of pressure and vacuum impregnation, using weight percent gain （WPG） as the basic index. The results are as follows： 1） On the basis of the orthogonal design and an actual experiment, the optimum preparation technology of Chinese fir wood/Ca-MMT composite board is 20% PF resin dispersion concentration （wt%）, 1.0 CEC amount of organic intercalation agent, 0.098 MPa vacuum degree, 5% concentration of Ca-MMT and 1.0 MPa pressure. 2） The WPG of the composite board samples of 450 mm length was much larger than that of the samples of 600, 750 and 900 mm length. Warm water extraction contributed little to WPG展开更多
With montmorillonite （MMT） organically modified as organophilic MMT （OMMT） and water-soluble phenol formaldehyde resin （PF） as intermediate, Chinese fir （Cunningharnia lanceolata） wood/MMT nanocomposites （WMN...With montmorillonite （MMT） organically modified as organophilic MMT （OMMT） and water-soluble phenol formaldehyde resin （PF） as intermediate, Chinese fir （Cunningharnia lanceolata） wood/MMT nanocomposites （WMNC） were prepared via nano intercalation compounding and characterized by XRD, SEM and FTIR. Results show that： 1） the preparation of OMMT is very successful; 2） the self-made PF can effectively intercalate into MMT to increase markably its gallery distance and even exfoliate its nano silicate laminae; 3） the XRD analysis indicates that some exfoliated MMT enters the non-crystallized region of microfibrils in wood cell walls and the crystallinity degree of wood in WMNC decreases; 4） the SEM graphs show that multiform MMT exists in WMNC. Some grains block in wood cell lumen, some layers adhere to the wood surface of the inner cell wall and some exfoliated nanolaminae even insert into wood cell walls; and 5） the FTIR analysis suggests that MMT and wood in WMNC perhaps interact via certain chemical bonding.展开更多
The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the...The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the nanocomposites of Chinese fir （Cunningharnia lanceolata） wood and montmorillonite （MMT） were prepared via three impregnation methods, i.e. normal pressure, once and twice vacuum methods. Based on the weight percent gain （WPG） of impregnated wood, the effects of compounding wood and MMT in terms of concentration, impregnating temperature and time, wood moisture content and wood extraction treatments, on sapwood and heartwood are discussed. Results show that： 1） the optimum MMT concentration in the impregnation solution is 3% for sapwood and 5% for heartwood; 2） room temperature is suitable in practice; 3） treatment pressure should be set at a high enough value in order to ensure sufficient permeation; 4） the effects of different impregnation methods on sapwood and heartwood are different, the heartwood extractives affect WPG significantly; cell wall permeability of sapwood is better than that of heartwood; 5） the cold water, hot water and benzene-ethanol solution extractions can all greatly improve the permeability of heartwood, hot water can dissolve some hemicellulose of low aggregation and hot water extraction improves wood cell wall permeability; 6） with an increase in wood moisture content, the permeable space in wood is reduced, but with a certain amount of water, instantaneous spaces are created and the permeation dynamic increases. This effect is especially apparent for difficult impregnating situations in heartwood and impregnation under normal pressure.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
Polyaniline-intercalated montmorillonite( PANI-MMT)was prepared via in-situ intercalative polymerization and used as the adsorbent for the removal of reactive green 19( RG-19) dye from water. The structure,composition...Polyaniline-intercalated montmorillonite( PANI-MMT)was prepared via in-situ intercalative polymerization and used as the adsorbent for the removal of reactive green 19( RG-19) dye from water. The structure,composition and specific surface area of asprepared composite were characterized using Fourier transform infrared spectroscopy( FT-IR),X-ray diffraction( XRD) and surface area analyzer. The adsorption of RG-19 by PANI-MMT was investigated as a function of contact time,temperature and pH. The results indicated the adsorption kinetics of RG-19 onto PANI-MMT followed the pseudo second-order model best among the pseudo firstorder,pseudo second-order and Elovich kinetic models. The equilibrium data fitted the Langmuir model better than the Freundlich model. Moreover,the maximum adsorption capacity for RG-19 decreased with the increase of initial solution pH. It can be concluded that the PANI-MMT can be a potential adsorbent for RG-19 removal from water.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 30271055)
文摘Studying new wood composites through nano science and technology (NSC) will develop new compounding theory of wood, and accelerate the combination of new technology, wood science, material science and other disciplines. The compounding of wood and inorganic MMT on nanoscale molecular level has high potential to greatly improve the mechanical properties, fire retardance, abrasion resistance, decay resistance, dimensional stability and other properties of wood. Based on the great achievements of polymer/montmorillonite (MMT) nanocomposites, this paper reviewed nano intercalation compounding methods (i.e. in-situ intercalative polymerization and direct polymer intercalation), and discussed the structure, properties and modification of montmorillonite (MMT). According to the main chemical components and particular structure of wood, the authors discussed the liquefaction and plasticization of wood, compared the dissolvability and meltability between wood and polymer, and then systematically put forward the basic idea, technological processes and schematic diagram to prepare wood/MMT nanocomposites (WMNC). The key technology to prepare WMNC is either to introduce delaminated MMT nanolayers into wood with the help of some intermediate polymers, or to obtain liquefied wood or plasticized wood from the complicated natural composite. It is applicable and effective to realize wood/MMT nanoscale compounding with the help of proper intercalation agent and medium polymer through the proposed 搊ne-step?or 搕wo-step?impregnating processes.
基金the National Natural Science Foundation of China (Grant No.30271055)
文摘For this study, an intercalation compounding method was used to prepare Chinese fir wood/Ca-montmorillonite （Ca-MMT） composite board to improve its properties such as surface mechanical properties, flame retardance and dimensional stability. By virtue of water-soluble phenolic resin （PF）, Chinese fir wood and Ca-MMT were mixed by pressure and vacuum impregnation. The optimum impregnation technology of Chinese fir wood/Ca-MMT composite board was obtained by using an orthogonal design and a single factor design of pressure and vacuum impregnation, using weight percent gain （WPG） as the basic index. The results are as follows： 1） On the basis of the orthogonal design and an actual experiment, the optimum preparation technology of Chinese fir wood/Ca-MMT composite board is 20% PF resin dispersion concentration （wt%）, 1.0 CEC amount of organic intercalation agent, 0.098 MPa vacuum degree, 5% concentration of Ca-MMT and 1.0 MPa pressure. 2） The WPG of the composite board samples of 450 mm length was much larger than that of the samples of 600, 750 and 900 mm length. Warm water extraction contributed little to WPG
文摘With montmorillonite （MMT） organically modified as organophilic MMT （OMMT） and water-soluble phenol formaldehyde resin （PF） as intermediate, Chinese fir （Cunningharnia lanceolata） wood/MMT nanocomposites （WMNC） were prepared via nano intercalation compounding and characterized by XRD, SEM and FTIR. Results show that： 1） the preparation of OMMT is very successful; 2） the self-made PF can effectively intercalate into MMT to increase markably its gallery distance and even exfoliate its nano silicate laminae; 3） the XRD analysis indicates that some exfoliated MMT enters the non-crystallized region of microfibrils in wood cell walls and the crystallinity degree of wood in WMNC decreases; 4） the SEM graphs show that multiform MMT exists in WMNC. Some grains block in wood cell lumen, some layers adhere to the wood surface of the inner cell wall and some exfoliated nanolaminae even insert into wood cell walls; and 5） the FTIR analysis suggests that MMT and wood in WMNC perhaps interact via certain chemical bonding.
基金This study was financially supported by the National Natural Science Foundation of China （Grant No. 30271055）.
文摘The nano intercalation compounding of wood and MMT has important implications for the modification of wood and for the development of new materials. With water-soluble phenol formaldehyde resin as an intermediary, the nanocomposites of Chinese fir （Cunningharnia lanceolata） wood and montmorillonite （MMT） were prepared via three impregnation methods, i.e. normal pressure, once and twice vacuum methods. Based on the weight percent gain （WPG） of impregnated wood, the effects of compounding wood and MMT in terms of concentration, impregnating temperature and time, wood moisture content and wood extraction treatments, on sapwood and heartwood are discussed. Results show that： 1） the optimum MMT concentration in the impregnation solution is 3% for sapwood and 5% for heartwood; 2） room temperature is suitable in practice; 3） treatment pressure should be set at a high enough value in order to ensure sufficient permeation; 4） the effects of different impregnation methods on sapwood and heartwood are different, the heartwood extractives affect WPG significantly; cell wall permeability of sapwood is better than that of heartwood; 5） the cold water, hot water and benzene-ethanol solution extractions can all greatly improve the permeability of heartwood, hot water can dissolve some hemicellulose of low aggregation and hot water extraction improves wood cell wall permeability; 6） with an increase in wood moisture content, the permeable space in wood is reduced, but with a certain amount of water, instantaneous spaces are created and the permeation dynamic increases. This effect is especially apparent for difficult impregnating situations in heartwood and impregnation under normal pressure.
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Industrial Research Project of Shaanxi Science and Technology Department,China(No.2014K08-35)
文摘Polyaniline-intercalated montmorillonite( PANI-MMT)was prepared via in-situ intercalative polymerization and used as the adsorbent for the removal of reactive green 19( RG-19) dye from water. The structure,composition and specific surface area of asprepared composite were characterized using Fourier transform infrared spectroscopy( FT-IR),X-ray diffraction( XRD) and surface area analyzer. The adsorption of RG-19 by PANI-MMT was investigated as a function of contact time,temperature and pH. The results indicated the adsorption kinetics of RG-19 onto PANI-MMT followed the pseudo second-order model best among the pseudo firstorder,pseudo second-order and Elovich kinetic models. The equilibrium data fitted the Langmuir model better than the Freundlich model. Moreover,the maximum adsorption capacity for RG-19 decreased with the increase of initial solution pH. It can be concluded that the PANI-MMT can be a potential adsorbent for RG-19 removal from water.
