A Study of the Mechanical Properties in Composite Materials with a Dammar Based Hybrid Matrix and Reinforcement from Crushed Shells of Sunflower Seeds.

Marius Marinel Stănescu,Alexandru Bolcu

doi:10.3390/polym14030392

Abstract

The production of composite materials through the reuse of waste or by-products from the agri-food industry will be a challenge for environmental protection. This study focuses in that direction. In the first stage, composites were made with the hybrid resin matrix (with three major volume proportions of natural Dammar resin and epoxy resin) and the reinforcing from shredded shells of sunflower seeds. Based on the tensile and compressive stresses, the stress–strain and strain–strain diagrams were obtained. The surface area of the rupture was investigated with stereo-microscopic analysis, and the absorption/loss of water was studied with a high precision balance. The vibration behavior was investigated experimentally, determining the damping coefficient and its own frequency. In the second stage, the study of these materials was extended. Sandwich composites were made with the same type of hybrid matrix as in the first stage. The core was made of shredded shells of sunflower seeds and the outer faces of linen fabric. These composites were applied to the bend (in three points), being obtained the force-deformation diagrams. The determined mechanical properties allow the complete or partial realization of these composites of some furniture components or of some equipment used in the field of constructions.

Highlights

IntroductionSociety’s development has led to the widespread use of plastic due to the possibility of obtaining cheap finished products
Shredded sunflower seed shells are “waste from the production process” of oil factories and the amount obtained is significant. This waste can be an alternative to “wood sawdust”, which is becoming more expensive and more difficult to find due to environmental protection measures
The mechanical behavior of the studied composites depends on the proportion of natural Dammar resin in the hybrid resin used as a matrix

Summary

Introduction

Society’s development has led to the widespread use of plastic due to the possibility of obtaining cheap finished products. This has led to a continuous increase in the amount of waste that is difficult to recycle and has harmful effects on the environment [1]. Reducing the use of petroleum derivatives is one of the current concerns of polymer science [2,3]. The production of composite materials based on natural resins and fibers reduces the use of non-biodegradable polymeric materials and creates environmentally friendly alternatives. Obtaining high-performance composites involves the use of long natural fibers that usually require specific procedures that lead to additional energy consumption [8]

Methods

Results

Conclusion