Study On The Preparation And Properties Of Camellia Oleifera Abel.Fruit Shells Based Wood Composite Materials

Camellia Oleifera Abel, fruit shells (C. Oleifera fruit shells) are the main oil residue of camellia plants, which is one of the important edible oil plants in China. And it has the characteristics of cheap, renewable, abundant and concentrated production. Wood-based composite material is a kind of environmental material, because of excellent performance and can instead of partly wood resources, it attracts domestic and international attention.This thesis based on the premise that characteristics of C. Oleifera fruit shells were analysed in depth, explored the effects of adhesive type, particle size and alkali treated C. Oleifera fruit shells on physical and mechanical properties of particleboard by the methods of total divisor experiment. The effects of grain size and mass fraction of C. Oleifera fruit shells and dosage of KH550 on physical and mechanical properties of C. Oleifera fruit shell powder(CA)/PP composite materials by orthogonal test. Then the effects of alkali treatment on properties of composite materials and effect and adding 5% boric acid on improvement of flame retardancy of composites were studied on, analysed and represented the properties of CA/PP composites by using Scanning Electron Microscope(SEM), Fourier Transform Infrared Spectroscopy(FTIR), thermogravimetric(TG) and cone calorimeter.Firstly, the basic physical and chemical properties of C. Oleifera fruit shells were studied in this thesis. C. Oleifera fruit shells and general wood materials with similar performance while also existed obvious differences. In C. Oleifera fruit shells, including 2.69% ash and 8.59% benzene alcohol extractive and 37.84% hemicellulose, which were all generally higher than the other two kinds of woods; but it had lower cellulose content. Compared with Cunninghamia Lanceolata and poplar, the results of thermal stability and combustion performance showed that both of C. Oleifera fruit shells should be improved through some methods. Concentration of NaOH 1% treated C. Oleifera fruit shells at room temperature, 1h, it could improve the wetting property of C. Oleifera fruit shells, which provided method for improving the interface compatibility. Comprehensive analysis of the results, C. Oleifera fruit shells can be applied for preparing wood-based composites.The experiment of preparing C. Oleifera fruit shells particleboard indicated, the mechanical performances all did not meet the requirements of the National Standard for particle board, but it may be produced panel with low mechanical strength requirements.The experiment of preparing CA/PP composites indicated, under the conditions of hot-pressing temperature 180℃, pressure about 4MPa, pressing time 15min, powder size 60-80mesh, the mount of C. Oleifera fruit shells powder 40wt%, the content of KH550 3wt%, the mechanical performances of CA/PP composites were ideal.Comparison the mechanical performances of CA/PP composites and poplar powder/PP composites at the optimal technology, the impact strength and MOR was same, while MOE of the former needed to be improved. By the analysis of Fourier Transform Infrared Spectroscopy(FTIR) and thermogravimetric(TG), the interfacial compatibility between C. Oleifera fruit shells and PP was not good, and the thermal stability of CA worse than poplar, but the thermal stability of CA and PP multiple system was better than poplar powder and PP multiple system.It was found that after alkali treatment, MOE of CA/PP composites were improved obviously. FTIR analysis showed that molecular structure of hemicellulose, cellulose and lignin happened different degree changes. Thermal gravimetric analysis indicated that although thermal stability of C. Oleifera fruit shells was destroyed but that of multiple system was improved.After adding 5% boric acid, the mechanical performances of CA/PP composites mechanical properties turned worse, because of the unsatisfactory dispersion effect, the existence of boric acid had a bad effect on interface compatibility between C. Oleifera fruit shells and PP. On heating, Boric was decomposed into B2O3 crystal then it covered on the surface of board, which could delay the thermolysis of materials, and conducive to form the temperature gradient and reduce the generation of the harmful gas such as CO rate and yield, it indicated that adding boric acid could improve the flame retardant and smoke suppression effect of CA/PP composites.