Preparation Of Silsequioxane Hybrid Material From Rice Husk And Property Study

The resource of rice husk in China is very rich, but the utilization and recycle are still low-level and even it becomes polluted in some regions. The main characteristic of the rice husk is the high content of silicon. If we can make use of it to produce organic chemicals with high additive value, we would not only enlarge the scope of application of the rice husk but also solve the pollution problem. Therefore, it would produce significant benefits of economy and society.Organic/inorganic hybrid POSS(Polyhedral oligomeric silsesquioxanes) is cubical organic/inorganic hybrid materials. The structure of POSS is performed in formula of T_n (T=RSiO_1.5, n=1,2,…). The skeleton cage structure of POSS (which is described by (RSiO_1.5)₈ in this paper) has special functions. It can be integrate with other polymer with active groups. And this product has a good performance with modified effect.In this article, the premaration process of cage shape silsequioxane (SSO) was expounded primarily, in which rice husk was used as the base material. The rice husk ash (RHA) was produced by rice husk through the carbonization. Orthogonal experiment was designed to achieve an optimized condition. In this condition, active SiO₂ was extracted from the RHA and the tetramethyl-ammonium silicate was produced.The structure of POSS was attributed by Fourier transform infrared spectroscopy, Nuclear magnetic resonance and Mass Spectrography. And the result of the research on tetramethyl-ammonium silicate produced by the RHA was compared with the result by the tetraethoxy silane, we found that the core of POSS was hexhedral cages which were linked with Si-O-Si, each silicon vertex can accept one branch which has a Me₄N-, so POSS has eight branches.The structure of the product was analysed by Infrared Spectrometer(IR), mass spectrometry(MS), Gel Permeation Chromatographic(GPC) and nuclear magnetic resonance Spectrum Analysis (NMR). The molecular struction was verificated that the core of the structure unit was constituted by octahedron cage-type with Si-O-Si bond. Each Si atom was linked with a branch and there were eight branches in a structure unit. Every brance contains two active groups with hydroxyl. POSS with more hydroxyl can be polymerized with other polymer. Thus the polymer can be modified as the cage of POSS linked in its molecule. This paper studied on modification of epoxy with POSS. The thermal degradation process of the epoxy cured by POSS was analyzed with TG(thermogravimetry) method in air atmosphere. Studies of the nanoindentation and nanoscratch were performed on the modifying system to evaluate the effect of the fabrication processes on their mechanical properties(hardness, elastic modulus, fracture force, friction coefficient, etc).