Characterization of the poly(vinyl alcohol)/cellulose whisker gel spun fibers

The current work reports the preparation and characterization of the nanocomposites reinforced with highly oriented cellulose whiskers (CWs) in a polymer matrix. The nanocomposites were prepared using polyvinyl alcohol (PVA) and a stable suspension of CWs prepared from cotton. The macroscopically homogeneous PVA-CW suspensions were gel spun. The produced fibers exhibited a high orientation of CWs in a direction parallel to the fiber axis. A DSC study of the PVA-CW fibers showed no crystallization exotherm during cooling after PVA melting due to the transformation of PVA to a polyene structure caused by the surface sulfate groups of the CWs. Storage modulus (E') of the composite fibers showed outstanding enhancement with increasing CW content, even with a small amount of CWs (5 wt.% of solid PVA). This is attributed to the favorable interaction between PVA and the CWs through hydrogen bonding and effective stress transfer from PVA to the CWs. (C) 2011 Elsevier Ltd. All rights reserved.