| Shell has compolicated structure and element.This paper studies pyrogenation of freshwater breeding nacre and mussel,and discusses the influence of shell on the pyrogenation process of macromolecule material.Observation on vertical section of shell through SEM shows there are two cracks in shell at 280℃ for 10min and microfabric of prismatic layer and nacre of having calcined shell transforms. The pyrogenation process of organic and inorganic compounds of pearl shell breeding in freshwater are studied by Fourier transform infrared spectroscopy (FTIR),X-Ray Diffraction (XRD) and thermogravimetric analysis at different temperature. The experiments show that one portion of amino organic compounds in the shell is changed to the volatilizable amine and the other portion is transformed to the involatile nitrate after pyrogenation.The organic compounds disappear completely at 600℃.They also show that the aragonite phase of calcium carbonate in pearl shell chang with temperature;the aragonite phase transforms to calcite at 500℃, but some of organic compounds is still residual;and calcium carbonate begins to decompose to calcium oxide at 600℃.This paper also studied pyrogenation of composites which are made up of three polymer(polyvinylchloride,ethylene-vinyl acetate copolymer and nylon12) and the shell at different temperature through analysed pyrolysis mechanism.The study shows:the calcined shell has different effect on resin at different temperature, nylon 12 having amido and shell calcined for two hours at 600℃ can form the material which has resemblance in the structure of shell,so the pyrolysis speed of this composite is slower than pure nylonl2,but the effect is unideal.The pyrolysis speed of other composites which are made up of resin and shell quicken.Therefore,the pyrolysis temperature of shell having calcium carbonate is very high but the shell inappositely act as the stabilizer of polymer. This is instructing meaning to study additive and assistant of shell in the future.
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