Properties of polyvinyl alcohol/halloysite nanotubes biocomposite films
Loading...
Date
2019-05
Authors
Tew Maei Nee
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
In this study, polyvinyl alcohol (PVA)/halloysite nanotube (HNT) biocomposite film was prepared by using solution casting method in the presence of glycerol as plasticizer and glutaraldehyde as crosslinking agent. The effect of HNT addition on the film was studied based on the tensile properties, water absorption, water vapour transmission properties and biodegradability. Initially, the HNT content added to the PVA matrix was varied from 1 g to 4 g. The tensile strength and elongation at break of film increased to optimum with the incorporation of 2 g HNT to PVA matrix, then decreased with continous addition of HNT. This was primarily due to the poor interfacial adhesion arising from fillers agglomeration. Besides that, the 2 g HNT filled PVA blend film showed higher water barrier properties. The soil burial test revealed that the incorporation of HNT enhanced the film’s biodegradability since substantial losses in weight and tensile properties especially at higher HNT loading with the presence of microbes had been found in the buried blend film. Secondly, HNT was partial replaced by silica in PVA matrix to form ternary blend system. The PVA/HNT/silica blend film exhibited lower tensile properties and higher water barrier properties with the increasing of silica content which were attributed to the dense network structure formed between silica particles and PVA matrix. After subjected to one month soil burial, PVA/HNT/silica film experienced a reduction in tensile strength and elongation at break with increasing of silica content. Meanwhile, the weight loss of buried PVA/HNT/silica film was lower than that of buried PVA/HNT film and this results was supported by FESEM micrograph as there was no severe crack found on the PVA/HNT/silica film’s surface, indicating that the microorganism was unfavourable toward silica filled film. Lastly, eggshell powder (ESP) was used to replace the HNT gradually in order to study the effect of hybrid fillers on the properties of PVA/HNT/ESP film. The blend film showed lower tensile properties yet higher water barrier properties with the increasing of ESP content. This was because of the lower hydrophilicity of ESP as compared to the HNT. Additionally, throughout the soil burial degradation test, ESP had been found successfully improved the biodegradability of the blend film. This result had been supported by obvious reduction of tensile properties, significant weight loss and severe holes found on the buried PVA/HNT/ESP films.