Optimization of Physical and Mechanical Properties of an Active Film of PLA/EEP by a Full Factorial Design

摘要

The objective of this work is to develop an active food packaging material based on poly (lactic acid) and ethanolic extracts propolis.Poly(lactic acid)/ethanolic extract propolis films are prepared by casting,using a three level full factorial design that allowed to study the parameters influencing Young's modulus and water absorption.Many experiments are carried out,with a suitable choice of two variables,leading to a mathematical model in the form of a first degree polynomial.The films are subjected to several analyzes: physical and mechanical properties and antibacterial activity.The results show that the optimal film is obtained with an amount of 14% w/w of ethanolic extracts propolis,giving an antimicrobial food packaging material with the following characteristics: amount of propolis extract: 0.14 g,Young's modulus: 1594.16 N mm~(-2),water absorption rate: 3%,breaking stress: 29.45% and elongation at break: 39.27%.