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Chitosan and starch rich source of inexpensive, biocompatible, biodegradable, but it is also a renewable resource. So for their product development, especially for disposable products, such as food packaging and medical products, is to solve the current problem of environmental pollution an effective way. But in the course, chitosan and starch products, the biggest problem is the strong hydrophilicity, once placed in a humid environment, they decreased stability of the product. Moreover, the relatively poor mechanical properties, and thermal stability of the barrier also limits the range of their use. Therefore, chitosan and starch products in order to improve overall performance, we made the following studies: (1) the functional groups with different (-COOH,-SO3H,-NO2) zirconium phosphonate (org-ZrP) as the shell chitosan (CS) fillers studied org-ZrP types of functional groups on chitosan structure, morphology and properties. IR results showed that the organic phosphonic acid, zirconium (org-ZrP) and chitosan (CS) to the strong interface, thereby enhancing the mechanical properties of the chitosan membrane, wherein the sulfonated benzene phosphonic acid, the enhanced effect of the zirconium good. Different effects may be enhanced by the phase interface caused by different modes of action. The stronger interfacial interaction, enhance the better. In addition, the CS / org-ZrP-n value absorbent composite film (Mu) were also tested. The results showed that, CS / ZrNP best moisture barrier composite film, which may be due ZrNP itself weak adsorption of water molecules caused. (2) successfully prepared chitosan / titanium phosphate (CS / TiP-n) composite film, and by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal gravimetric analysis (TGA) were used to investigate titanium phosphate adding chitosan membrane structure, morphology and properties. Infrared (FTIR) The results show that the composite membrane and matrix CS TiP formed between the strong hydrogen bonds, thereby increasing the interface compatibility. The SEM picture can be observed, when the content is relatively came TiP, TiP particles can be well dispersed in the chitosan, but with the increase of the content of the composite membrane appears in section TiP particle agglomeration. Mechanical test results showed that adding 0.4 wt% of TiP can make chitosan membrane tensile strength (σb) and elongation at break (εb) increased by 35.1%, 37.0%. Moisture barrier tests show that adding 0.8wt% TiP, chitosan membrane moisture value (Mu) decreased 41.7%. Meanwhile, compared to films of pure CS, CS / TiP thermal stability of the composite film has also been improved. (3) first preparing a functional group having a-COOH glycine-N, N-bis-methylene phosphonic acid, titanium (TGDMP), infrared spectroscopy (FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM) and other methods be characterized. Followed by a series prepared by tape casting TGDMP containing different amounts of chitosan / organic acid titanium (CS / TGDMP) nanocomposite films. Experimental results show that, TGDMP accession of chitosan mechanical properties, thermal stability and moisture resistance are increased. In addition, we studied the environmental moisture content on the mechanical properties of the composite membrane. The results showed that the greater the relative humidity environment, the tensile strength of the composite film is smaller, the larger the elongation at break. (4) prepared by casting a series of pea starch / graphene oxide (PS / GO-n) complex membrane, using infrared spectroscopy (FTIR), X-ray diffraction (XRD), atomic force microscopy (AFM), Thermal gravimetric analysis (TGA), UV - visible (UV-vis) methods such as its structure, morphology and properties were characterized. Experimental results show that the filler and the matrix PS GO form strong hydrogen bonds between, so that the compatibility between the two is improved. When the GO content was 2.0 wt%, the starch film tensile strength (σb) and Young's modulus (E) respectively, from 4.56 MPa, 0.11 GPa increased to 13.79 MPa, 1.05 GPa, and the elongation at break down from 36.06% to 12.11%. Furthermore, GO adding starch film also improves moisture barrier and thermal stability, while reducing the transmission of ultraviolet light.
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