|
Title
Enhanced thermal behavior mechanical properties and UV shielding of polylactic acid (PLA) composites reinforced with nanocrystalline cellulose and filled with nanosericite
Authors
CHIH-PING CHANG I-CHEN WANG YUAN-SHING PERNG
Received
September 3, 2011
Published
Volume 47 Issue 1-2 January-February
Keywords
polylactic acid, nanocrystalline cellulose, nanosericite, thermal gravimetric analysis, UV shielding
Abstract
The objectives of this study were to utilize nanocrystalline cellulose (NCC) and nanosericite (NS) as reinforcing and
functional filling agents compounded in a polylactic acid (PLA) substrate for forming novel nanocomposite materials,
and subjecting the composites to field-emission electron microscopy (FE-SEM), tensile strength, thermomechanical
analyses, thermal gravimetric analysis and UV-Vis spectroscopic analyses; so as to investigate the effect of the
modifications achieved by incorporating the nanomaterials on the surface properties, tensile strength, glass transition
temperature (Tg), storage modulus, thermal gravimetric loss and shielding efficacy against UV light of different
wavelengths. The results indicated that adding suitable quantities of NS and/or NCC to a PLA substrate could improve
the overall thermal stability, mechanical strength and UV shielding capacity of the resulting nanocomposites. The
shortcoming of weak bonding between NS and PLA could be ameliorated with the addition of NCC. The simultaneous
addition of NS and NCC to the composite substrate exerted a greater contribution to the enhancement of the overall
functionalities, compared to either bipartite compounds. Based on our results, at a 3% NS and 7% NCC addition rate to
the PLA substrate, the most optimal tensile strength was obtained. At temperatures <250 °C, the nanocomposites
exhibited good thermal stability and could effectively block about 65% of UVB and UVC irradiation. In the future, the
formulations might be applied as a biodegradable UV shielding coating film, or alone, as a medical wrapping material
or packaging material.
Link
|
