Compatibilizing and toughening of the styrene and acrylonitrile copolymer and core‐shell impact modifier obtained by agglomerate technologies

Abstract Particle size distribution and the compatibility of core‐shell impact modifiers play a crucial role in determining the mechanical properties of the resin. This study presents the synthesis of a core‐shell impact modifier, a copolymer of polybutadiene grafted with styrene and acrylonitrile (PBL‐g‐SAN), using emulsion polymerization to enhance the mechanical properties of SAN resin. Polymer agglomeration technologies were employed to increase the particle size of polybutadiene latex, resulting in particles approximately 300 nm in diameter. Moreover, the effects of core‐shell modifiers with different constitutions on the mechanical properties of ABS resin were investigated. By optimizing the grafting polymerization process, improvements in impact strength of ABS resin were observed. When the St/AN ratio of the core‐shell modifier is 75/25, with a core‐shell ratio of 60/40 and MMA content at 2.5%, the impact strength of ABS resin reaches its peak while maintaining high tensile strength. The incorporation of methyl methacrylate improved the dispersion of core‐shell modifiers in SAN resin. Compared to commercial ABS resins with the same SAN and rubber content, the modified resin demonstrated a nearly 20% improvement in impact performance, and significant reductions in both production time and costs due to the polymer agglomeration method. Highlights The 300 nm polybutadiene latex was synthesized by polymer agglomeration technology. The relationship between the composition of these core‐shell modifiers and the mechanical properties of ABS resin was explored. The ABS resin with impact strength exceeding 20% of commercial material is prepared.