| Polymer/Montmorillonite (MMT) intercalation nanocomposite is one of the most widely studied and most promising composites. China is rich in Ca-MMT mineral resources. Due to its particular intercalation chemistry and nanoscale layers with very high aspect ratio and high strength, ion-exchangeable and swellable MMT play an important role in producing high-performance intercalation nanocomposites. The intercalation nano-compounding of wood and MMT is creative thinking and practice, which has important scientific significance and attractive application prospect. The intercalation compounding of organic wood and inorganic MMT on nanoscale molecular level is a pioneer study to improve or modify wood. In this paper, for the first time, the technology way to compound wood and MMT on nanoscale is systematically put forward. First, Na-transformation and organic modification of Ca-MMT are comprehensively studied and organic MMT is successfully obtained. Second, Water-soluble PF/MMT intercalation nanocomposite is prepared. Then with PF as compounding intermediate wood/MMT intercalation nanocomposite is prepared. This exploring research provides a new idea to modify wood and a new approach to prepare wood/inorganic composite.In this study, calcium cations (Ca2+) in Ca-MMT are first exchanged with sodium cations (Na+) which are easier to be substituted by organic cations; and the hydrophilic Na-MMT is modified by organic reagent to be hydrophobic and be compatible with polymer; then by virtue of water-soluble phenol formaldehyde (PF) resin wood and MMT are compounded on nanoscale through vacuum-impregnation. In this way wood/MMTintercalation nanocomposite (WMNC) is prepared. With the analyses of scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer-differential thermal analyzer (TG-DTA) and other measures, the following results are obtained.(1) With Na+ substituted for Ca2+, the swell capacity, swell value and cation-exchange capacity (CEC) of MMT are greatly improved. Compared with Ca-MMT, Na-MMT has bigger interlayer distance (JooiX lower crystallinity, better colloid properties and higher activity. The optimum parameters to transform Ca-MMT into Na-MMT are: MMT dispersion concentration in water, 15%; the addition amount of sodium carbonate, 4%; reaction temperature, 60 C; reaction time Ih.(2) The organic modification of MMT has great effect on the preparation of MMT nanocomposite. The interlayer distance of organic MMT (OMMT) is remarkably enlarged, and some MMT sheets exfoliate to be single nanolayers and disperse freely. The hydrophilic layer surface is modified to be organophilic. The thermal-stability of OMMT is greatly improved. So the organic modification of MMT in this study is very successful. The optimum technology is: organic intercalation agent, CIS; MMT grain granularity, 200 mesh; aged time in water, 24h; MMT dispersion concentration in water, 5%; intercalation agent concentration, 0.3mol/L; intercalation agent amount, exceeding 50% CEC; the pH value of medium, 4; proton donor, vitriol (H2SO4); reaction temperature, 80 C; reaction time, 1.5-2h; vacuum-drying; drying temperature, <120 C; moisture content, l%-3%. The main factors in an order of influence are: addition amount of intercalation agent > MMT water dispersion concentration > reaction time > the acidity or alkalinity of medium (pH value) > reaction temperature.(3) The organically modified MMT has good compatibility with self-synthesized water-soluble PF resin. Partially intercalated and partially exfoliated PF/MMT nanocomposites (PMNC) are easy obtained. PF compounded with OMMT has improved thermal properties. There may be some strong linking effect between MMT and PF which is relative to oxygen atom. If phenol, formaldehyde and OMMT are compoundedsimultaneously, it is called one-step method. One-step way is affected by many factors and the reaction is very complicated, so its investigation is very difficult. If the PF resin is synthesized in advance befo...
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