Hybrid composites of fillers and/or fibers reinforced polymer was generally produced by masterbatch dilution technique. In this work, the simplified preparation was introduced for the large volume production of 30 wt % short-fiber and talcum reinforced polymer hybrid composite by direct feeding into twin-screw extruder. Multifunctional epoxide-based terpolymer and/or maleic anhydride were selected as in situ reactive compatibilizers. The influence of fiber and talcum ratios and in situ reactive compatibilizers on mechanical, dynamic mechanical, morphological and thermal properties of hybrid composites were investigated. The morphological results showed the strong interfacial adhesion between fiber or talcum and Poly(lactic acid) (PLA) matrix due to a better compatibility by reaction of in situ compatibilizer. The reactive PLA hybrid composite showed the higher tensile strength and the elongation at break than non-compatibilized hybrid composite without sacrificing the tensile modulus. Upon increasing the talcum contents, the modulus and storage modulus of hybrid composites were also increased while the tensile strength and elongation at break were slightly decreased compared to PLA/fiber composite. Talcum was able to induce the crystallization of PLA hybrid composites.

Filament-wound composite has distinct interfaces differing from conventional metals, and the fracture at these interfaces (macroscopic fracture) causes a remarkable decrease in strength and stiffness.In this investigation, the behavior of macroscopic fracture (delamination) of filament-wound tubes was observed underr static lateral compression and the crack initiation at the end cross-sections of tubes was examined by the finite element method using the polar-anisotropy.The followings were revealed from the results.(1) The fracture behavior in filament-wound tubes under lateral compressive load was affected by winding-angle of reinforcement, and various fracture modes were observed for the specimens with variable winding-angles.(2) On the numerical analysis, the domains involving microscopic fracture were produced at different locations predictable from the anisotropic or isotropic properties. Therefore, for the design of filament-wound tubes the anisotropic effect should be taken into consideration.