Morphological investigation of cellulose acetate/cellulose nanocrystal composites obtained by melt extrusion

作者:Ferreira Leite Liliane Samara; Battirola Liliane Cristina; Escobar da Silva Laura Caetano; Goncalves Maria do Carmo
来源:Journal of Applied Polymer Science, 2016, 133(44): 44201.
DOI:10.1002/app.44201

摘要

Composites were prepared from cellulose acetate (CA) and cellulose nanocrystals (CNC) by melt extrusion using two methods for the introduction of CNC: direct mixing and predispersion in CA solution. CNC were isolated using hydrochloric acid to increase thermal stability allowing the composites to be processed above 150 degrees C. The effect of CNC dispersion on the composites morphology, thermal, and mechanical properties was investigated. Field emission scanning electron microscopy and transmission electron microscopy results indicated that the predispersion method allows better CNC dispersion and distribution when compared to the direct mixture method. In addition, predispersion promotes preferential CNC orientation in relation to the injection flow. The predispersion method also showed a 14% Young's modulus increase in composites containing 15 wt % CNC while no significant change was observed when using the direct mixing. The results obtained in this work show that, to achieve the percolation threshold, nanoparticle distribution is as important as their content.

  • 出版日期2016-11-20