| Non-renewable energy exhausting and environment pollution brought a series of problems which influence the health of human and sustainable development in recent years. Therefore, sources, environment friendly, safe, nontoxic and renewable nature polymer composites materials become the research focus. Cellulose is the most abundant biomass resources on the earth, it can construct the environment friendly materials through physical method. For another, polyaniline (PANI) is one of the most potential applications of conducting polymers. Therefore, construction of the cellulose and conductive polyaniline composite materials will build a new approach of multifunctional composite materials, which would be in optical, electrochemical, biomedical and other fields have potential application prospects.Utilizing cellulose, aniline and polyaniline as raw materials, novel functional materials were fabricated directly from solutions through non covalent bond interaction, which were dissolved in alkli/urea aqueous solutions at low temperature, respectively. Meanwhile, the structure and properties of materials were characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), mechanical testing, solid state 13C NMR, solid state 31P NMR, UV-vis spectroscopy (UV) and N2 adsorption. The correlation between structure and properties was studied. Especially, the potential application in energy storage fields was also evaluated by electrochemical performance test, and the potential application in biomedical fields was also evaluated by biological experiments.The innovation of this work was listed as follows:(1) The nanoporous structure of cellulose hydrogel is used as template to in-situ synthesize PANI via the limited interfacial polymerization method, leading to one conductive side in the polyaniline/cellulose composite hydrogels at first time, and proved that they can promote nerve regeneration; (2) Constructed nanoporous structure of cellulose microspheres by using the cellulose solution and emulsion method. Using the nanoporous structure as a micro reactor, constructed of the polyaniline/cellulose composite microspheres in the presence of phytic acid, and it could be as the high efficient supercapacitor materials; (3) The hierarchical N/S-codoped carbon microspheres (NSC-SP) were fabricated facilely by pyrolyzing the cellulose/PANI composite microspheres containing dodecyl benzene sulfonic acid as dopant, which were constructed through the method of emulsion, as an anode for sodium-ion batteries (SIBs) exhibited superior rate capability and long cycle life; (4) N/P doped carbon materials were fabricated facilely by pyrolyzing the nanoporous polyaniline/PA/cellulose composite microspheres, as a supercapacitor material, show good cycle stability; (5) Based on the hydrogel bonding between the MMT and cellulose matrix, forming high strength cellulose/MMT composite films, the hexadecylpyridine bromide was fixed well in the cellulose/MMT matrix through cation exchange, leading to the excellent antibacterial activities against The primary contents and conclusions of this work can be divided into five parts:In order to construct the scaffold materials of nerve repair, the cellulose hydrogel is used as template to in-situ synthesize PANI via the limited interfacial polymerization method via U tube, leading to one conductive side in the composite hydrogels. PANI nanoparticles size and shape are controllable by adjusting the polymerization time and concentration of oxidant. The 3-D network structure of cellulose as micro reactor of aniline monomer polymerization, and also provides a frame fixed micro-nano-structure of polyaniline. The hydrophobic PANI nanoparticles are immobilized in the hydrophilic cellulose via the phytic acid as"bridge" at presence of water through hydrogen bonding interaction. The PANI/cellulose composite hydrogels exhibited good mechanical properties and biocompatibility as well as excellent guiding capacity for the sciatic nerve regeneration of adult Sprague-Dawley rats after 3 month without any extra treatment. On the basis of that the pure cellulose hydrogel is an inert material for the neural repair, PANI play an indispensable role on the peripheral nerve regeneration. The hierarchical micro-nano-structure and electrical conductivity of PANI could remarkably induce the adhesion and guiding extension of neurons, showing its great potentials in biomedical materials.To resolve the problem of the pulverization and rapid capacity fading of polymer electrodes, novel electrode materials were constructed from polyaniline/cellulose microspheres (PANI/CM), which were fabricated via in situ synthesis of PANI on cellulose matrix by using phytic acid (PA 10%) as a "bridge", for the first time. The PAN I/PA/CM successfully resolved the problem of the pulverization as electrode materials of PANI. In our findings, the PANI subparticles with nanomesh structure were dispersed homogeneously in the cellulose microspheres from inside to outside, as a result of the firm connection between the hydrophobic PANI and the hydrophilic cellulose through the PA "bridge" to create micro- and nano-porous architecture. Meanwhile, the other parts of PANI deposited on the surface of the microspheres to form a loose coralline structure, leading to the ion channels for the electrolyte penetration. The PANI/PA/CM composite electrodes exhibited excellent cycling stability and high rate capability, showing great potential for use in energy-storage devices.The hierarchical N/S-codoped carbon microspheres (NSC-SP) were fabricated facilely by pyrolyzing the cellulose/PANI composite microspheres containing dodecyl benzene sulfonic acid as dopant via a "green" and low cost route. The doped nitrogen and sulfur heteroatoms could induce the defects, narrow the band gap and expand the interlayer of NSC-SP, leading to the significant enhancement of Na adsorption capability, mobility and electronic conductivity of NSC-SP. And it makes carbon layer spacing expand from 0.37 nm to 0.41 nm. First principles calculation results show that the N/S co-doping make sodium ion diffusion barrier decreased from 203 to 158 meV, significantly reducing sodium ion diffusion resistance. The experimental results indicated that NSC-SP as anode materials of sodium-ion batteries (SIBs) exhibited high capacity (30 mA g-1～280 mA h g-1), superior rate capability (10 A g-1～130 mA h g-1), and long cycle life of more than 3400 cycles. This work provides a new method for constructing sodium ion battery anode carbon material, and it is more economic for preparation of large-scale energy storage materials which use renewable resources through environmental friendly method.N/P doped carbon materials were fabricated facilely by pyrolyzing the nanoporous polyaniline/phytic/cellulose composite microspheres. In order to find out the factors of influence the electrochemical properties, different carbonization conditions were studied. The capacitance value is small under the two electrode system, it is not reach expected target of industrial application. The carbon material have good stability and cycle stability after carbonization at 900℃. Therefore, it need to modify the materials, improve the capacity value while maintaining good cycle stability.The transparent cellulose composite films with antibacterial activities were constructed by dispersing montmorillonites (MMT) into cellulose solution through a simple and low cost method. The cellulose/MMT composite films were characterized by SEM、TEM、FTIR, the results revealed that MMT was dispersed well in the cellulose matrix, and formed the high strength organic/inorganic composite films. It was observed that hexadecyl pyridine bromide (HB) was fixed well in the cellulose/MMT matrix through cation exchange. When the bacteria contact RCM5-HB composite films, HB released from the composite films, and adsorption on the surface of bacteria, then diffuse through the cell walls of bacteria in the body, so bacteria were killed, which make composite films have good antibacterial activity. It is important in their application of anticorrosion packaging materials.This thesis developed a series of polyaniline/cellulose functional materials by using alkali/urea aqueous solvents at low temperature or in situ synthesis of polyaniline in cellulose base. Thus, construct a series of cellulose/polyaniline composite functional materials, and research the structure and function relationship of structure-property. These polyaniline/cellulose composite materials would find wide application in electrochemical energy storage, tissue engineering scaffold material, and other fields. These basic researches provide a new "green" method for the design and development of conductive polymer, and construct environment friendly materials by renewable cellulose, which are in accordance with national sustainable strategy. Therefore, this thesis exhibits scientific significance and application prospect. |
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