Enhancing interface compatibility in high-filled coal gangue/polyethylene composites through silane coupling agent-mediated interface modification

This study investigates the profound impact of surface modification using the silane coupling agent KH550 on Coal Gangue (CG)-Polyethylene (PE) composites. The aim was to enhance the properties of composites while addressing waste material accumulation concerns. Comprehensive analyses elucidated the mechanism of interface formation and the subsequent influence on composite properties. Surface modification of CG with KH550 demonstrated pronounced effects on physical, mechanical, and thermal properties of the resulting composites. Notably, the coupling agent facilitated covalent bonding with CG, preventing particle agglomeration and enhancing dispersion stability. The introduction of KH550 contributed to heterogeneous nucleation, augmenting composite crystallinity and interfacial bonding with the resin, thereby improving overall compatibility. Mechanical tests revealed substantial enhancements in tensile and bending strengths with optimal KH550 content. However, excess KH550 led to diminishing returns, highlighting the critical balance required for effective modification. Thermal stability assessments demonstrated improved properties owing to KH550 modification, validating its role in safeguarding the composite matrix from thermal degradation. Microstructural analyses, including SEM, FTIR, DSC, and XRD, provided insights into the interface morphology, chemical composition, crystalline behavior, and structure of the composites. The SEM micrographs elucidated a progressive shift from clear interface boundaries to more homogenously blended states with increasing KH550 content, indicative of enhanced interaction between CG and PE. This comprehensive study demonstrates that KH550 modification offers a strategic approach to optimize CG-PE composites, showcasing potential applications in the automotive and construction industries. Those findings underscore the significance of surface modification techniques in enhancing composite properties and utilizing waste resources efficiently.