Using Factorial Design Methodology to Assess PLA-g-Ma and Henequen Microfibrillated Cellulose Content on the Mechanical Properties of Poly(lactic acid) Composites

M Dzul-Cervantes,A Valadez-Gonzalez,T Tábi,P J Herrera-Franco

doi:10.1155/2017/4046862

Abstract

In this work, a 22 factorial design was used to study the effect of microfibrillated henequen cellulose fibers (HENCEL) and PLA-g-MA coupling agent contents on the tensile, flexural, and impact mechanical properties and the heat deflection temperature (HDT) of biodegradable PLA composites. The results show that the principal effects of HENCEL and MA are statistically significant for the tensile, flexural, HDT, and impact strength properties of PLA composites. Regarding the interactions between the principle effects, MA-HENCEL, there are differences with respect to the mechanical property; for example, for tensile and flexural mechanical properties, there is a synergistic effect between MA and HENCEL, whereas for HDT and impact strength there is not any. The micromechanical analysis shows an excellent agreement between the measured and the estimated values for both the composite tensile strength and the elastic modulus and only slight deviations were noticed for high microfibrillated cellulose fibers content. The morphological analysis via SEM indicated that the addition of PLA-g-MA improved the fiber-matrix adhesion because of the HENCEL unbounding and pull-out decreases from the PLA matrix. The use of appropriate values of matrix strength and stiffness and considering the improved fiber-matrix adhesion of the coupling agent yield a good agreement between experimental and estimated values.

Highlights

Nowadays, most polymeric materials are made from monomers derived from petroleum; this is a nonrenewable resource
Regarding the interaction between the principle effects, Maleic anhydride (MA)-henequen cellulose (HENCEL), there are differences with respect to the mechanical property; for example, for tensile and flexural mechanical properties, there is a synergistic effect between MA and HENCEL, whereas for heat deflection temperature (HDT) and impact strength there is not any statistical evidence of synergistic effect between both factors
A 22 factorial design was used to study the effect of microfibrillated henequen cellulose (HENCEL) and Poly(lactic acid) (PLA)-g-MA coupling agent contents on the tensile, flexural, and impact mechanical properties and the heat deflection temperature (HDT) of biodegradable PLA composites

Summary

Introduction

Most polymeric materials are made from monomers derived from petroleum; this is a nonrenewable resource. The disposal of items derived from petroleum, such as fast food utensils, containers for packaging, and garbage bags, has created major environmental problems [1, 2]. To solve these problems, the recycling of materials made from petroleum and the development of new materials with more friendly features to the environment are an attractive alternative, such as being biodegradable and, ideally, made from renewable sources [3]. In order to be competitive with the petroleum derived polymers, biopolymers need to have acceptable prices and to be processed using similar methods to those used for the processing of synthetic plastics [7, 8]

Methods

Results

Conclusion