| The new green material and new green energy become the propulsion of the economic development in China with global warming.Al/H2O based fuel is one kind of new high-energy fuels, which adopts H2O as the oxidant and Al as the fuel. The energy density of Al/H2O based fuel is quite large. In addition, Al/H2O based fuel is one kind of green fuels, whose combustion products have low pollution and are very friendly to the surroundings.As an alternative resource, biomass has been attracted a lot of attention recently for its potential application in both regenerated energy and substitutes for petroleum product. Cellulose and chitosan are the major component of the biomass and the most affluent biopolymer in the world, and they are also a potential feedstock for preparing different kinds of novel polymers and material which are environmentally friendly and biocompatible.The dissertation can be logically divided into two parts. Part I pays much attention to experimental investigations of Al/H2O based fuel. The influences of some other addition agents, including nano amorphous state B-Co alloy, CL-20, HMX, MMA, etc., were studied, and some basic parameters were obtained. At 300 oC, 450 oC, 600 oC, the flash pyrolysis of the key addition agent polyacrylamide were carried out in argon, respectively. Moreover, the formation mechanism for liquid and gas products, as well as the effects on improving the characteristics of Al/H2O propellant were discussed. Part II focuses on the preparation of cellulose/graphite oxide composites, chitosan/graphite oxide composites and all-cellulose composites. The morphology of the prepared composites were investigated, and the special properties of these composites were examed.The findings obtained from the above researches are summarized as following.(I) Research progresses on Al/H2O based fuels and biomass, including some basic properties, the combustion behaviors, the improvement methods for fuels'characteristics, the structure and treatment for the biomass, and so forth, were reviewed.(II) A variety of experimental methods were employed to study Al/H2O based fuels detailed. Nano amorphous state B-Co alloy was prepared. B-Co alloy was used as an addition agent for basic Al/H2O based propellant. The addition of PAM evidently improved the energy release and burning rate of propellants, as well as decreased the pressure exponent. Besides, HMX addition not only had better effect in increasing the temperature of burning surface but also made Al powders burn much thoroughly, compared with CL-20 addition.(III) At 300 oC, 450 oC and 600 oC, the flash pyrolysis investigation of polyacrylamide (PAM) solution was carried out in an off-line furnace-type pyrolyzer with Ar as the carrier gas. There were a few flammable small molecules, which were believed to favor the combustion of the propellants and improved the energy release. (IV) Regenerated cellulose (RC)/graphite oxide (GO) blend films and fibers were prepared in 6wt%NaOH/4wt%urea aqueous solution via a simple and low cost pathway. The results revealed a certain miscibility, good thermostability and mechanical properties of the regenerated-cellulose composites blending with less than 7.5 wt% of GO. All the results demonstrated that GO was well-dispersed in the cellulose matrix, and there were strong H-bonding between hydroxy groups of the cellulose and hydroxy groups of the GO. The obtained composites own higher mechanical strength than the pure regenerated cellulose film, especially at high temperature.(V) Chitosan/graphite oxide composite films and Hydrogel have been prepared in which graphite oxide (GO) is used as filler and diluted acetic acid is used as solvent for dissolving and dispersing chitosan and GO, respectively. The results revealed that chitosan and graphite oxide mixed with each other homogeneously and the mechanical properties were improved significantly compared with the pure chitosan. Interestingly, with an increase ratio of chitosan to GO from 1.5/0.1 (wt/wt) to 1.5/0.3 (wt/wt), the tensile strength of the films at dry and wet states increased from 80.3 to 137.5MPa and 14.6 to 43.9 MPa, respectively. All the results demonstrated that GO was crosslinker in the composites, and there were strong H-bonding between hydroxy groups of the chitosan and hydroxy groups of the GO. The obtained composited films owned higher mechanical strength than the pure chitosan film, especially at wet state.(VI) PEG/NaOH aqueous solution, a recently reported solvent system for cellulose was utilized to prepare an all-cellulose composite. The composite was produced from commercial filter paper by converting a selective dissolved fiber surface into a matrix. When the filter paper was immersed in the pre-cooling solution more than six hours, the all-cellulose composites are molding. Such composite has possessed a nice interface between the remaining fibers and the surrounding matrix from the selectively dissolved and re-solidified fiber surface, which results in an excellent bonding, a high mechanical performance and an optical transparency. In addition, the all-cellulose composite is totally composed of sustainable cellulosic resources, so it is biodegradable after service.
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