Preparation of poly (styrene-methyl methacrylate)@grafted halloysite microspheres and the properties of its composite fibers

It has become a hotspot that microfibrils with a high aspect ratio have a good reinforcement effect on the composite fibers. To prepare the micro-fibrillation composite fibers with excellent performance and good dispersity, poly (styrene-methyl methacrylate)@grafted halloysite nanotubes(PSM@PMHNTs) microspheres were prepared by suspension polymerization method, and the PSM@PMHNTs reinforced composite fibers were prepared by simple blending with polymethylmethacrylate (PMMA). The structure and mechanical properties of the composite fibers were studied by transmission electron microscopy, scanning electron microscopy, dynamic thermo-mechanical analysis, and universal material testing machine. The results showed that polystyrene grafted halloysite nanotubes (PMHNTs) had good hydrophobicity and were successfully embedded in poly (styrene-methyl methacrylate) (PSM). The mechanical performance of microfibril composite fiber with PSM@PMHNTs is better when compared that with PMHNTs and PSM, and the elongation at break of the composite fiber has dramatically increased by 120.90% compared to that of pure PMMA. In addition, the mechanical properties of the composite fibers were increased firstly and then decreased with the increase of PMHNTs contents and draft ratios, while the glass transition temperature of the composite fibers had no obvious changes. The composite fiber has the best mechanical properties when the content of PMHNTs is 1.0 wt% and the draft ratio is 6, and the tensile strength and elongation at break were 26.94% and 256.36% higher than that of pure PMMA, respectively.