Mechanical properties improvement of thermoplastic corn starch and polyethylene-grafted-maleicanhydride blending by Na⁺ions neutralization of carboxymethyl cellulose

• Main Authors: Kittisak Jantanasakulwong, Somchai Wongsuriyasak, Pornchai Rachtanapun, Phisit Seesuriyachan, Thanongsak Chaiyaso, Noppol Leksawasdi, Charin Techapun
• Format: Journal
• Published: 2018
• Subjects: Biochemistry, Genetics and Molecular Biology
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85052147281&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/58198
• Institution: Chiang Mai University

© 2018 Elsevier B.V. Corn starch was melt-blended with glycerol (70/30) to prepare thermoplastic starch (TPS) at 140 °C for 10 min. The TPS was melt-blended with polyethylene grafted with maleic anhydride (PE-MAH) and carboxymethyl cellulose (CMC) to improve the properties of the TPS. Phase determination analysis and SEM images demonstrated that the morphology of the TPS/PE-MAH/CMC blend consisted of PE-MAH particles dispersed in the TPS matrix. The tensile strength and elongation were found to have improved with the addition of CMC 5 wt%. Adhesion between the polymers was observed by the asymmetric double-cantilever beam (ADCB) method. The PE-MAH/(TPS + CMC) sample showed high fracture toughness (Gc), which is related to the adhesion energy between the two polymers. This is suggestive of interactions between the MAH groups of PE-MAH and CMC. FT-IR results indicated that the neutralization and aggregation were formed by Na+ions of CMC and the MAH of PE-MAH, which increased the interfacial adhesion between TPS and PE-MAH blend. The improvement in the mechanical properties of the TPS/PE-MAH/CMC blend is concluded to be because of the increase in the interfacial adhesion between TPS and PE-MAH by these neutralization and aggregation processes.