Toughening of polyamide 12/nanoclay nanocomposites by incompatible styrene‐butadiene‐styrene rubber through tailoring interfacial adhesion and fracture mechanism

Abstract

AbstractThe main drawback of polyamide 12 (PA 12)/nanoclay nanocomposites in their wide range of potential engineering applications known as diminished toughness was overcome using incompatible styrene‐butadiene‐styrene block copolymer (SBS) rubber. Applying optimal processing parameters for co‐rotating twin‐screw extrusion resulted in strong interfacial adhesion of matrix and rubber and intercalated and delaminated nanoclay stacks confined in the matrix. The formulation of compatibilized PA 12/SBS/nanoclay nanocomposites was optimized by employing response surface Box–Behnken methodology. A combination of microscopic methods, that is, atomic force microscopy, transmission and scanning electron microscopy, and transmission optical microscopy, along with single‐edge‐double‐notch four‐point‐bending technique, was exploited to exhaustively explore the toughening mechanisms and microstructure. The findings verify that by tailoring the rubber/matrix interfacial strength and nanocomposite morphology, the Izod impact strength of PA 12/nanoclay nanocomposites is noticeably improved even by incorporating an incompatible rubber and tough fracture mechanisms including rubber particle cavitation and large‐scale shear yielding are attained.