Study on the effect of carbon fiber addition on the properties of rice straw-plastic composites

Abstract

Short carbon fiber (SCF), rice straw powder, and high-density polyethylene (HDPE) were melted, mixed, and compounded into composites by compression molding. The effects of carbon fiber content on the mechanical properties of rice straw-high density polyethylene composites (RHCs) were studied. The carbon fibers were characterized by a universal capability test machine (UCTM), scanning electron microscope (SEM), DMA dynamic mechanical analyzer, and a Fourier infrared spectrometer. The results showed that the addition of carbon fiber was beneficial to reduce the creep of RHCs. Meanwhile, the carbon fibers were broken after strength testing. The functional group types of rice straw WPC composites did not change, and the skeleton structure of WPC materials was still retained. When the content of carbon fibers was 9%, a large number of carbon fibers were surrounded by the HDPE matrix; the fibers were broken and rarely pulled out. The results showed that good interfacial bonding took place between the carbon fibers and the composites. The maximum tensile strength of the RHC/S9 was 15.15 MPa, which was 20.7% higher than that of default RHC, and the modulus of elasticity was 52.5% higher than that of default RHC. However, due to the large content of carbon fiber, the distribution of the carbon fibers was uneven in the matrix, and the toughness was reduced.