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Polyelectrolyte complexes (Polyelectrolyte complexes, PEC) are an important class of multi-component polymer materials. The low concentration of the the PEC dispersion liquid in the field of genes and DNA transfer, controlled drug release, microcapsules, flocculation and paper enhancement has been widely applied. Solid-state PEC general insoluble, however, does not melt, it is difficult to process, this shortcoming severely limits its versatility advantage play. Therefore, so far, the material structure of PEC body - the nature and applied research is scarce. In this paper, acid protection - to protect \Charged PEC layers of preparation and application of self-assembled multilayer films, first discovered PEC fractal self-assembly. Selection of poly diallyl dimethyl ammonium chloride (PDDA), poly-methacryloxyethyl trimethyl ammonium chloride (PDMC) and chitosan (CS) is a cationic polyelectrolyte, carboxymethyl cellulose anionic polyelectrolyte, sodium (CMCNa) proposed the the acid protection - to protect the \Hydrochloric acid concentration of the critical value of 0.001 ~ 0.03M. Using IR, elemental analysis, differential scanning calorimetry instrument, thermogravimetric and wide-angle X-ray diffraction studies PEC solid nature, found the PEC amorphous, no glass transition. Viscosity, zeta potential, and light scattering, scanning electron microscopy, transmission electron microscopy and atomic force microscopy to study the dispersion properties of PEC, the basic structural unit of the internal cross-linking, the negatively charged needle / rod-PECA nanoparticle aggregates. Further study the the PEC dispersion of self-assembly found to be the formation of dendritic fractal pattern (fractal tree). The studied fractal tree structure, formation and regulation. Found that the fractal tree pattern by PECA particles self-assemble to form a thickness of approximately 400-600nnm dimension in between 1.75-1.81. The PEC dispersion of self-assembly process meets the diffusion limited aggregation model, negatively charged PEC nanoparticles between the masking effect is the key to the formation of the fractal tree. Increased the PEC dispersion liquid concentration, solvent evaporation temperature and reduce the pH of the dispersion liquid, the organic solvent is added to the dispersion and change the the PEC chemical structure are destroyed the formation of fractal tree \The solution cast film method, the polysulfone base film prepared PDDA-CMCNa, CS-CMCNa PDMC-CMCNa the three homogenization PEC membrane pervaporation isopropanol dehydration performance. Found that the the PEC film on the water - isopropanol dehydration radiate high selectivity (through the liquid water content gt; 99.1 wt% of) and ultra permeability. , PDMC-CMCNa HPECM0.46 at 70 ℃ to 10 wt% water - isopropanol dehydration flux of up to 4.2 kg/m2h, respectively 4 and 5 times the raw material CMCNa film and commercialization of polyvinyl alcohol film . The proposed water channel structure model to explain the the PEC membrane ultra-high pervaporation performance. By the degree of complexation is 0.28 the the PDDA-CMCNa PEC0.28 and the polyvinyl alcohol obtained in a blend film (weight ratio 1:1) 70 ° C for a 10 wt% water - isopropanol dehydration through amounted 1.35 kg/m2h, more commercial polyvinyl alcohol film about 1 times. Proposed in situ ion complexation prepared containing silica and multi-walled carbon nanotubes PEC nanohybrid film. Found that below the critical content of 5 wt% and 7 wt%, silica and carbon nanotubes in the PEC base body of good dispersibility. When the best carbon nanotubes content (7 wt%), PDDA-CMCNa PEC / MWCNT nanohybrid film tensile strength, modulus and elongation at break 65Mpa, 2.8 Gpa and 3.4%, respectively, for the pure PEC film 2.7,2.3 and 1.8 times. The pervaporation experiments showed that the dispersed silica and carbon nanotubes of PDDA-CMCNa PEC, nanohybrid membrane maintained excellent permeability and selectivity of the PEC substrate. Charged the PDDA-CMCNa PEC nanoparticles as new layers of self-assembled primitives to build on the success of the quartz plate, polyacrylonitrile porous bottom film and fiber multilayers. PECA particles as an assembled unit can speed up the assembly process. Example, the (PDDA CMCNa PECA-/PDDA-PSS by PECA) 10 multilayers growth rate up to each of the double-layer 200 nm on a quartz plate. The growth rate of the multilayer film with the PEC nano particles complexation increases, the pH of the assembled liquid is reduced and the applied concentration increased. Assembled in a multilayer film of the a polyacrylonitrile porous substrate film 50 ° C for a 10 wt% water - isopropanol dehydration, there is a higher permeation flux (1.39 kg/m2h). Assembly of the pH of the multilayer film on the optical fiber sensor has higher sensitivity (0.5nm/pH) and in response to the advantages of shorter time (48s).
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