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
<span style="font-family:Verdana;">Aminoethanoic acid undergoes condensation with 1,4-benzenedicarboxaldehyde</span><span><span><span style="font-family:""><sp...<span style="font-family:Verdana;">Aminoethanoic acid undergoes condensation with 1,4-benzenedicarboxaldehyde</span><span><span><span style="font-family:""><span style="font-family:Verdana;"> to form an O, N, N, O donor Schiff base, </span><i><span style="font-family:Verdana;">N,N'</span></i><span style="font-family:Verdana;">-di(carboxymethylene)</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">terephthalaldehyde, Ligand L. Coordination compounds of this Schiff base us</span><span><span style="font-family:Verdana;">ing Ni (II), Cu (II), </span><span style="font-family:Verdana;">VO</span><span style="font-family:Verdana;"> (IV) and Co (II) were then obtained </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;">. The</span></span><span style="font-family:Verdana;"> Schiff base and the complexes were evaluated for their antimicrobial and DNA binding abilities. Molecular docking studies of the ligand and synthesized compounds were also carried out. Evidence for the formation of the Schiff base coordination compounds and the coordinating atoms was obtained from </span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;">H NMR, infrared and ultraviolet spectral data, EDX, EDTA complexometric titration and magnetic susceptibility measurement. The results obtained are consistent with octahedral geometry for Ni (II) complex</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> the metal ion coordinating to one molecule of Ligand L</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> and</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> with additional coordination with two oxygen atoms of two molecules of the solvent. A square-planar geometry was suggested for both Co (II), and Cu (II) complexes and a five-coordinate, square pyramidal geometry for the VO (IV) complex. The results further indicated that the carboxylic acid of Ligand L was not deprotonated both in the free base and also the complexes. In addition, the results showed that Compound 2 elicited the best antimicrobial activity potential. Generally, the compounds exhibited considerable good affinity to CT-DNA.</span></span></span>展开更多
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
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
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<span style="font-family:Verdana;">Aminoethanoic acid undergoes condensation with 1,4-benzenedicarboxaldehyde</span><span><span><span style="font-family:""><span style="font-family:Verdana;"> to form an O, N, N, O donor Schiff base, </span><i><span style="font-family:Verdana;">N,N'</span></i><span style="font-family:Verdana;">-di(carboxymethylene)</span></span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">terephthalaldehyde, Ligand L. Coordination compounds of this Schiff base us</span><span><span style="font-family:Verdana;">ing Ni (II), Cu (II), </span><span style="font-family:Verdana;">VO</span><span style="font-family:Verdana;"> (IV) and Co (II) were then obtained </span><i><span style="font-family:Verdana;">in-situ</span></i><span style="font-family:Verdana;">. The</span></span><span style="font-family:Verdana;"> Schiff base and the complexes were evaluated for their antimicrobial and DNA binding abilities. Molecular docking studies of the ligand and synthesized compounds were also carried out. Evidence for the formation of the Schiff base coordination compounds and the coordinating atoms was obtained from </span><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;">H NMR, infrared and ultraviolet spectral data, EDX, EDTA complexometric titration and magnetic susceptibility measurement. The results obtained are consistent with octahedral geometry for Ni (II) complex</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> the metal ion coordinating to one molecule of Ligand L</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> and</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> with additional coordination with two oxygen atoms of two molecules of the solvent. A square-planar geometry was suggested for both Co (II), and Cu (II) complexes and a five-coordinate, square pyramidal geometry for the VO (IV) complex. The results further indicated that the carboxylic acid of Ligand L was not deprotonated both in the free base and also the complexes. In addition, the results showed that Compound 2 elicited the best antimicrobial activity potential. Generally, the compounds exhibited considerable good affinity to CT-DNA.</span></span></span>
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.
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.
