Development of PLA/EPDM/SiO2 blended polymer for biodegradable packaging

Herein, we developed a blended polymer of polylactic acid (PLA) and ethylene propylene diene (EPDM) for cosmetic packaging using dihydrogenated tallow-treated nanosilica to improve the compatibility between PLA and EPDM, which are immiscible. The PLA/EPDM ratio was maintained at 95/5, and the loading rates of the modified nanosilica powder were set at 0, 3, and 5 phr. Fourier-transform infrared spectroscopy demonstrated that the nanosilica particles adsorbed the cationic surfactant solution onto their surfaces. Scanning electron microscopy showed that the EPDM domain sizes within the PLA matrix reduced with increasing modified nanosilica amounts. Moreover, the modified nanosilica improved the compatibility between the PLA and EPDM phases. The tensile strength and elongation at break of the PLA/EPDM/SiO2 (95/5/5) polymer were 50.39 MPa and 32.8%, respectively. The degradation behavior of the polymer in water and a sodium lauryl ether sulfate (SLES) solution was evaluated. The decomposition rate of the polymer was higher in SLES with low polarity and was determined to be approximately 3.4 x 10(-8) s(-1). Moreover, during a disintegration test (ISO 16929:2019), the polymer exhibited a disintegration rate of 100%, degrading completely in 28 days.

Automated summary

In this study, a blended polymer of PLA and EPDM was developed for cosmetic packaging. The compatibility between PLA and EPDM was improved using modified nanosilica. The results showed that the modified nanosilica decreased the domain sizes of EPDM within the polymer matrix, leading to an increase in tensile strength and elongation at break of the polymer.