Effect of mastic gum integration on improvement of polylactic acid biodegradable films

Aydogdu Emir A., Akgun M., Kirtil E.

Polymer Engineering and Science, vol.63, no.5, pp.1539-1550, 2023 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 63 Issue: 5
  • Publication Date: 2023
  • Doi Number: 10.1002/pen.26304
  • Journal Name: Polymer Engineering and Science
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, Applied Science & Technology Source, Biotechnology Research Abstracts, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.1539-1550
  • Keywords: dispersion, food packaging, mastic gum, PLA, tensile properties, WVP, XRD
  • Çanakkale Onsekiz Mart University Affiliated: Yes


Currently, 90% of all packaging films are composed of non-renewable, petroleum-based materials. However, these materials have a significant environmental footprint. Polylactic acid (PLA) is a well-known biodegradable thermoplastic polymer. However, the use of PLA poses some inherent challenges, like the brittleness of PLA films. For this study, with the objective of overcoming the shortcomings of PLA films, mastic gum (MG), which is an under-utilized hydrophobic polymer, was incorporated into PLA, and the resultant films were characterized for their chemical (x-ray diffraction [XRD], Fourier-transform infrared [FTIR]), thermal (thermogravimetric analysis [TGA], dynamic mechanical analysis [DMA]), optical (optical microscope, color, and opacity), and barrier properties (water vapor permeability [WVP]). MG addition yielded films with much higher opacities and decreased WVPs up to 80%. Optical microscope images revealed the presence of some defects for films with MG concentrations above 1% g/g solvent, which also decreased the film's tear resistance. Glass transition temperature (Tg) values are reduced with MG addition, resulting in less rigid films at room temperature. In the end, MG incorporation yielded more flexible films with much better water barrier properties. In addition, all other properties of the films were drastically modified with MG addition. Hence, MG/PLA is demonstrated to be a promising biopolymer combination for the preparation of biodegradable films as a food packaging material.