Development of lightweight hybrid polymeric composites reinforced with cellulose microfillers derived from linseed oil cake

Abstract By focusing on the natural cellulose microfiller derived from leftover cakes in the oil mills, researchers have the opportunity to develop and investigate novel materials that can potentially revolutionize the field of lightweight structures. This research work focuses on the development of lightweight hybrid polymeric composites using a combination of novel materials derived from linseed oil cake biomass waste and unidirectional flax fibers with epoxy polymeric matrices. It also explores the potential of linseed oil cake biomass waste as a valuable source of cellulose fillers for reinforcement in polymer composites, providing an alternative to traditional synthetic fillers. In this work, the extracted cellulose was made into a composite using a polymeric matrix (epoxy resin), and its mechanical as well as acoustical characteristics were studied to determine its suitability for various applications. The primary aim was to enhance the mechanical properties and reduce the weight of the composites for potential applications in lightweight structures, including automotive components, aerospace structures, and other industries where weight reduction is crucial without compromising the mechanical performance. Evidence of cellulose crystallinity and α‐cellulose was apparent, as indicated by the higher intensity peaks observed at 2θ = 22.10°, corresponding to the 002 crystallographic planes. The thermogravimetric analysis showed a minimum mass loss of 4.12% occurring at 309.16°C. The sample with 7.5 wt% linseed oil cake cellulose in the flax composite exhibited the highest values for various properties, including a tensile strength of 77.62 MPa, a flexural strength of 115.62 MPa, and an impact strength of 35.5 kJ/m². For hardness and sound absorption properties, the sample with 10 wt% linseed oil cake cellulose in the flax composite exhibited the highest values (approximately 102 S_d) and a noise reduction coefficient value of 0.329. These findings suggest that combining cellulose with unidirectional flax fibers can make them suitable for various applications, such as structural components in the automotive industry, building materials, and biodegradable and eco‐friendly products. Highlights Researchers used linseed oil cake cellulose for lightweight composites. Novel materials hybridized linseed oil cake cellulose and flax fibers. The material is a potential alternative to synthetic fillers in polymer composites. The material can enhance mechanical properties for automotive, aerospace use. The material has yielded promising results in tensile, flexural, impact strength, and sound absorption.