Electromagnetic interference properties of carbon nanofiber–reinforced acrylonitrile–styrene–acrylate/natural graphite composites

Abstract

Acrylonitrile–styrene–acrylate/natural graphite/carbon nanofiber composites (ASA/NG/CNF) were prepared using a melting blending method. The effects of CNFs on the morphology, rheological properties, dynamical mechanical properties, electrical resistivity, and electromagnetic interference shielding effectiveness (EMI SE) were studied using a scanning electron microscope, a rotational rheometer, and dynamic mechanical analysis (DMA). The addition of CNFs changed the oriented and laminated structure of the ASA/NG composite. The flexural strength of the ASA composite reached a maximum at 6% CNF, and then it began to decrease. The addition of CNFs did not alter the glass‐transition temperature of ASA, but it largely increased the storage modulus of the composite in DMA tests. In the rheological measurements, the complex viscosity and storage modulus of the composite increased as CNF content increased, and the resistance to creep of the composites was significantly increased by the addition of CNFs. The electrical resistivity of the ASA composites decreased from 49.8 Ω cm to 2.3 Ω cm as the CNF content was increased from 0 to 12%. At the same time, the EMI properties of the composites rose from 15 dB to 30 dB in the frequency range 30–1500 MHz. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45455.

Effects of hybrid fillers on the electrical conductivity, EMI shielding effectiveness, and flame retardancy of PBT and PolyASA composites with carbon fiber and MWCNT

“…Therefore, it is thought that higher content of CF can be easily damaged by the increased collision between the fillers of the composite . The longer CF length may affect the formation of electrical pathway and consequently result in the increased electrical conductivity of the polymer/ CF composite …”

“…Song et al . 's study of poly(acrylonitrile‐co‐styrene‐co‐acrylate) (PolyASA) with graphite (40 wt %) and carbon nanofiber composite reported the EMI SE of 15–30 dB when the carbon nanofiber content was increased from 0 to 12 wt %, respectively.…”

“…Polymer/conductive filler composites are known as electromagnetic shielding materials . Hwang's study of poly(butylene terephthalate) (PBT)/carbon fiber ( CF ) (30 wt %) composite reported the electrical conductivity and electromagnetic interference shielding effectiveness (EMI SE) to be 1.7 × 10 −4 S cm −1 and 11.1 dB at the frequency of 1.1 GHz, respectively.…”

Effects of carbon fiber modification with multiwall CNT on the electrical conductivity and EMI shielding effectiveness of polycarbonate/carbon fiber/CNT composites

“…As the use of electronic devices increases, research into electromagnetic wave shielding polymer composites is becoming more active . This is because the electromagnetic wave causes malfunctions of electronic devices, and harmful influences on the human body .…”

“…This is because the electromagnetic wave causes malfunctions of electronic devices, and harmful influences on the human body . There are three main types of electromagnetic shielding materials, which are metals, conductive polymers, and polymer composites . The metals block the electromagnetic wave by plating or backscattering, but they are poor to process, easy to oxidize, and heavy .…”