Biocarbon-based sustainable reinforcing system for technical polymers. The structure-properties correlation between polycarbonate (PC) and polybutylene terephthalate (PBT)-based blends containing acrylonitrile-butadiene-styrene (ABS)

The sustainable filler system consisting of biocarbon (BC) particles and short basalt (BF) and carbon (CF) fibers was used as the reinforcement for PC/ABS and PBT/ABS type blends. The melt blending procedure includes the preparation of hybrid composite samples, where part of the fibrous filler was replaced by biocarbon powder. Reference samples were prepared with BF and CF fibers. For all samples, the content of the fillers was 20 wt%. The prepared materials were manufactured using the injection molding technique, while during this procedure, different types of standard testing samples were molded, including application samples. For part of the samples, the thermo-oxidative heat aging procedure was applied. All samples were subjected to characterization procedures, including mechanical and thermomechanical tests and structure properties examination. The comparison of the modulus value for BF/BC composites shows a modulus increase of 100%, from 2.5 GPa to over 5.0 GPa for both types of composites (PC and PBT), and the stiffness for CF/BC samples exceeds 6.0 GPa. The increase in thermal resistance compared to the unmodified PBT/ABS matrix was 20 degrees C for the composite of the BF/ BC system and 10 degrees C for the CF/BC samples. The increase for hybrid samples based on PC/ABS did not exceed 12 degrees C. The obtained results confirmed that the presence of BC particles was not leading to thermal degradation of the matrix blend; however, the mechanical performance of the hybrid composites was slightly lower. As a result of the heat aging procedure, the properties deterioration was more significant for PC/ABS-based samples since the mechanical performance was reduced after 1000 h of thermo-oxidation. However, the thermal analysis and structure observations did not confirm any significant changes in the macromolecular structure of the prepared materials, which confirmed the possible use in demanding applications.