Reinforcing effect of polyurethane sizing on properties of acrylonitrile–butadiene–styrene composites involving short carbon fiber

In this study, we present the influence of sizing layer of short carbon fiber (CF) to the basic properties of CF reinforced acrylonitrile–butadiene–styrene (ABS) composites. Composite samples are prepared with four different loading ratio of 5, 10, 15 and 20% by weight using melt-compounding. Surface topography, elemental analysis and surface functionality of CF samples are confirmed by atomic force microscopy (AFM), energy-dispersive X-ray (EDX) and infrared (FTIR) spectroscopy techniques, respectively. Characterizations of composites are performed based on mechanical, thermo-mechanical, melt-flow (MFI) and morphological performances of composites. According to test results, mechanical properties of ABS are enhanced with CF additions. Polyurethane (PU) sized CF containing composites display higher tensile strength, modulus and hardness compared to desized ones. CF additions lead to increase in glass transition temperature of ABS copolymer. MFI values of composites are found to be in narrow range, hence CF additions cause no effect for processing conditions of ABS. According to SEM analysis, CF surfaces are covered by polymer matrix thanks to PU sizing layer of CF, whereas debondings are formed for desized CF-filled ABS matrix. Results indicate that PU-sizing is suitable for ABS/CF composite system.