A high-resolution solid-state NMR study on starch-clay nanocomposites and the effect of aging on clay dispersion

作者：Zhang Xiaoqing^*; Dean Katherine; Burgar Iko M

来源：Polymer Journal, 2010, 42(8): 689-695.

DOI：10.1038/pj.2010.48

• aging effect
• exfoliation
• solid-state NMR
• starch-clay nanocomposite

High-resolution solid-state nuclear magnetic resonance (NMR) was applied as a bulk analysis method to provide an indication of clay dispersion in starch-clay nanocomposites. The starch composite containing 2.5 wt% nano-clay appeared as an exfoliated system with an average distance between clay platelets (<<(D)over bar>>) of around 40 nm. Increasing the amount of nano-clay to 5.0 wt% reduced the <<(D)over bar>> value to around 20 nm. Aging displayed a minimal effect on the exfoliation of starch-clay nanocomposites. However, the <<(D)over bar>> value became much larger on introduction of 5 wt% polyvinyl alcohol (PVOH) into the systems because of the formation of aggregated structures, and the <<(D)over bar>> value increased further after aging. The motion of PVOH molecules during the aging period could function as a driving force toward a more stable interaction between PVOH chains and clay platelets, thus resulting in a reduction in the degree of clay exfoliation in the starch matrix. Polymer Journal (2010) 42, 689-695; doi: 10.1038/pj. 2010.48; published online 2 June 2010

• 出版日期2010-8
• 单位CSIRO