Comparative study of physical, mechanical, heat transfer and morphological properties of goose down and wood fiber reinforced polypropylene biocomposites

Petroleum-derived polymer materials such as polypropylene/polyethylene and composites produced with these polymers have a wide range of uses in today's industry, but the harmful effects of petroleum-derived polymers and unnatural additives, their unsustainability, and the recent increase in environmental awareness have resulted in "biocomposites (composites containing biomaterials)" scientific studies and researches on the subject are increasing. It is considered necessary to reduce the use of materials or increase the efficiency of use due to reasons such as waste problems after use of these polymers, which are used extensively in the automotive industry, packaging and insulation industries. On the other hand, due to their low weight, good mechanical properties, ease of processing, insulation properties, and acoustic properties, biocomposites are used in many areas such as household appliances, automotive and aerospace industries and can be preferred instead of non-natural material-reinforced composite materials or polymers. In addition, biocomposites produced with polypropylene (PP) and natural reinforcement materials have the capacity to be an alternative to many common engineering materials and many polymer products used in the industry, due to their good mechanical properties and common usage areas. Goose down is a natural material that is used in textiles due to its high filling and good insulation properties. In this study, biocomposites reinforced with PP matrix, goose down and larch wood with high insulating properties were produced and their mechanical properties and insulation properties were also investigated. With the production of biocomposite materials formed with these two reinforcing products, it is aimed to develop an alternative material with better insulation properties, improved mass performance and pure polymers in the industrial field. Biocomposites reinforced with larch wood and goose feathers were processed at different rates and compared with each other. Biocomposite materials were produced with a 40 L/D twin screw extruder, and test samples were prepared by injection. Tensile and bending tests were carried out to determine the mechanical properties of the produced biocomposite materials. Density, thickness increase and water uptake tests were performed to determine the physical properties of the produced biocomposite materials, TGA analysis to determine their thermal properties, FTIR analysis for chemical characterization, sound absorption coefficient measurement for insulation properties and thermal conductivity coefficient tests were performed. As a result, apart from the tensile strength of the composite reinforced with 5% wood flour, it was found that the flexural and tensile strengths of biocomposites using both goose down and wood flour increased significantly up to 15%. It was determined that the tensile modulus increased with the use of reinforcement in the variations containing both wood flour and goose down. As a result of the thermal conductivity coefficient measurement, it was found that the samples containing wood were similar when compared with PP, the samples containing goose down showed a low conductivity coefficient compared to PP, and in the sound absorption coefficient test, the samples containing both wood flour and goose down had a higher sound absorption coefficient at high frequency. . With this information, it was observed that the water absorption and swelling rates of the samples containing wood flour were higher due to the hygroscopic chemical structure of the cellulosic material. With this study, environmentally friendly biocomposite materials with relatively good insulation properties, supported by relatively cheaper reinforcing materials, were produced.