Preparation And Characterization Of Novel Thermoplastic Starch Biocomposites

The Novel ThermoplasticStarch Biocomposites(TPS)was successful prepared by research of processing conditions of cassava starch and incorporation of bacterial cellulose(BC)nanofibers and PBAT(Ecoflex).The mesh structure of original BC and oxidation BC nanofiberswere observed by TEM;and the oxidation BC nanofibers were thinner than original BC fiber.From the SEM analysis it could be found that the granule structure of nature starch molecules wasdisappeared after being plasticized and gelatinized by the high temperature and strong mechanical forces for a long time.WAXD pattern of corn starch specimens appears four obvious diffraction peaks which are corresponding to the typical A-type crystallization.The original A-type crystallization peaks of starch disappear and only a weak diffraction peaks corresponding to the VH-type crystallization peaks appear in the TPS specimens.From the result of DSC thermal analysis of the TPS and TPS100BCx series specimens,a wide range but weak endothermic peak was found which was corresponding VH-type of starch crystallization melting.After blending BC nanofibers in TPS during their gelatinization processes,the tensile strength(af)values of TPS100BCxspecimens improved significantlyand reached a maximal value,as their PVA contents approach an optimum content.After incorporation of Ecoflex during processes of TPS100BCx,their moisture content was improved obviously.