Water absorption and its effect on the tensile properties of tapioca starch/polyvinyl alcohol bioplastics

Innovation in Polymer Science and Technology 2016

材料科学;化学

Judawisastra, H.^1 ; Sitohang, R.D.R.^2 ; Marta, L.^2 ; Mardiyati^1

Materials Science and Engineering Research Groups, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Ganesha 10, Bandung

40132, Indonesia^1

Alumni of Materials Science and Engineering Study Program, Institut Teknologi Bandung, Bandung, Indonesia^2

关键词: Gelatinization temperature;    In-water absorption;    Poly (vinyl alcohol) (PVA);    Solution-casting method;    Tensile properties degradation;    Water absorption behavior;    Water immersion;    Water saturations;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/223/1/012066/pdf
DOI  :  10.1088/1757-899X/223/1/012066

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Tapioca is one of the largest sources of starch and makes it suitable to be used for bioplastic material. Addition of polyvinyl alcohol (PVA) has been shown to successfully reduce the brittleness of starch bioplastic. This study aims to investigate the influence of PVA addition to water absorption behavior and its effect on the tensile properties of tapioca starch/PVA bioplastics, which are still not yet fully understood until now. The bioplastics were prepared by solution casting method at gelatinization temperature, with PVA addition from 0 to 29 wt%. Examinations were carried out by means of water absorption test, tensile test and Fourier Transform Infrared (FTIR) Spectroscopy. Increasing content of PVA, up to 29 wt%, was found to decrease the water absorption of the bioplastics, with the lowest water saturation point of 251%. This is due to the interaction between starch and PVA which reduces the free OH groups in the resulting bioplastics. Consequently, this led to a decrease in water absorption-related deterioration, i.e. tensile properties degradation of the bioplastics. The addition of 29 wt% resulted into the lowest degradation in tensile strength (6%) and stiffness (30%), while accompanied with the highest elongation increase (39%) after water immersion.