A polyethylene packaging film modified by thermoplastic starch and cloisite 30B

This study investigates the effects of incorporating thermoplastic starch (TPS) and organomodified montmorillonite (Cloisite 30B) on the performance of linear low-density polyethylene (LLDPE) films produced via the film blowing process for packaging applications. LLDPE was blended with different TPS contents (30–50 phr) and Cloisite 30B loadings (1–5 phr) to evaluate their influence on printability, optical transparency, oxygen permeability, water vapor transmission rate, and water absorption. Increasing TPS content reduced optical transparency due to light scattering and increased oxygen and water vapor permeability as well as water absorption owing to the hydrophilic nature of starch. The incorporation of Cloisite 30B improved oxygen barrier properties by creating tortuous diffusion pathways, while simultaneously increasing moisture sensitivity. Printability assessments using polar (water-based) and non-polar (solvent-based) inks revealed weak ink adhesion on TPS-containing films, with only marginal improvement observed upon addition of Cloisite 30B. X-ray diffraction analysis indicated partial exfoliation of Cloisite 30B platelets at low loadings (1 and 3 phr), whereas higher loading (5 phr) led to agglomeration and deterioration of film properties. Among the studied formulations, the film containing 40 phr TPS and 3 phr Cloisite 30B exhibited the most balanced combination of barrier performance and printability. The findings clarify the potential and limitations of TPS- and Cloisite 30B-modified LLDPE blown films for packaging applications.