Development and Assessment of Polyester Reinforced with Sansevieria Cylindrica/Zawa Flour Composites

Abstract

ABSTRACT. This paper zero in on preparation of hybrid composites in which Polyester matrix filled with Sanseveria cylindrica fiber (SCF) and Zawa flour. SCF fiber was taken 10% volume constantly in all the samples. Camera ready samples were prepared using hand layup technique in which filler constituent proportions were taken by using rule of hybrid mixture (RoHM). The mail aim of the composites is to increase the tensile flexural, and impact strengths, TGA, DSC results by incorporating the filler. It was observed that, tensile strength was linearly increased up to 4wt.% zawa after that sudden falling was observed. On other hand, tensile modulus was increased linearly up to 5wt.% was the clear indication of addition of zawa imparts more stiffness to the composites. Flexural strength was increased up 3wt.% zawa flour after than it starts depreciating suddenly. Flexural modulus was increased linearly up to 3wt.% zawa four composites after that decreases. Impact strength was optimised at 4wt.% zawa flour after that it starts going down. In DSC analysis, for 3wt.% zawa flour composite registered good performance than the 2wt.%,whereas in TGA analysis 3wt.% composite was having good performance than 2wt.% zawa flour composites. Reasons attributed for increased glass transition temperature was due to the less moisture content or due to the deprived of void due to the good bonding strength. INTRODUCTIONHybridization with two or more than two fibers in a single matrix leads to the development of hybrid composites. Usually a combination of two fillers proves to be useful in practice as it leads to achieve a balance between properties of single fiber reinforced composites. Till mid-1990s only glass, carbon and aramid fiber systems were worked upon. Bunsel, Harris, summer scales and Short and several other scientists have shown the characteristics of hybrid effects in the case of various glass and carbon fiber systems but the work on short fibers is limited. Scientists have explained in all these systems negative and positive hybrid effects in terms of mechanical properties. Short fiber composites are attractive structural materials for their relatively easy processability depending on resulting flow field and cooling conditions, a complex microstructure may result in different fiber orientations at different points of molded piece. Microstructure characteristics can only explain the local mechanical properties of short fiber composites. In a hybrid system various mechanical properties like stiffness strength and fracture toughness depend on the characteristics of constituent fibers like fiber length and fiber volume fraction. When fiber length is smaller than critical fiber length fiber pull out takes place but if fiber length is more than critical fiber length breaking of fiber occurs thus fracture mechanisms can be identified with the knowledge of critical fiber length. Polypropylene possess outstanding properties like low density, high softening point, good flex life,