Production and characterization of plant waste/grapehene/mineral reinforced polylactic acid composites

Polymers have a wide range of uses in our lives due to their superior mechanical and thermal properties. However, most of the polymers in use are petroleum-based and remain undegraded in nature for a long time. With the increase in environmental awareness, the tendency towards biocomposites produced using waste materials has increased. With this orientation, both waste materials are utilized and environmental pollution is reduced. In this thesis, biocomposite materials were produced by twin screw extruder and hot press methods using poly(lactic acid) (PLA) obtained from natural resources as an alternative to petroleum-based polymers, graphene as additive material, peach kernel shell as agricultural waste and huntite-hydromagnesite as mineral reinforcement. The effects of the produced biocomposite materials on physical, mechanical, thermal and morphological properties were investigated. The characterization results were evaluated comparatively with the control sample of pure PLA. SEM analysis revealed the presence of peach pits and huntite-hydromagnesite in the biocomposite samples. As a result of FTIR analysis, an increase in the absorbance level was observed in the bonds belonging to the carbonyl group of peach kernel. It was determined that the density values of PLA decreased with the reinforcement of peach pits and increasing the reinforcement ratio. However, an increase in these density values was observed with huntite-hydromagnesite reinforcement. When the mechanical test results are examined, the mechanical strength of peach pits and huntite-hydromagnesite containing mechanical strength decreases compared to pure PLA. When the biocomposite samples produced as a result of DSC analysis were compared with pure PLA, the addition of peach pits decreased the crystallization temperature and increased the degree of crystallization. Increasing the peach seed ratio increased the crystallization temperature and decreased the degree of crystallization. The addition of huntite-hydromagnesite minerals caused a significant decrease in crystallization temperature and a significant increase in the degree of crystallization. When the thermal deflection temperature values are examined, the thermal deflection temperatures decrease with peach kernel supplementation, while huntitehydromagnesite supplementation increases.