Control of the Structure of Core–Shell Elastomers for the Design of
MABS
Resin With Good Transparency and Toughness
Lu Xu, Yanxi Fu, Zimo Zhu, Chen Liang, Baijun Liu, Mingyao Zhang ABSTRACT
Achieving high transparency in methyl methacrylate‐acrylonitrile‐butadiene‐styrene (MABS) resins while maintaining excellent toughness remains a challenge, primarily due to light scattering at phase interfaces. Contrary to the conventional focus on matching the refractive index (RI) between the rubber core and the matrix, this work identifies the grafted shell layer as a critical, independent third phase governing optical properties. We systematically investigate two distinct refractive index matching schemes and demonstrate that optimal transparency is attained only when the RI of all three phases (rubber core, grafted shell, and matrix) is closely aligned. The independent existence of the shell phase is corroborated by two distinct loss peaks in dynamic mechanical analysis. Furthermore, we reveal that increasing shell thickness amplifies the impact of its RI on transparency, while an excessively thin shell compromises rubber particle dispersion, deteriorating both optical and mechanical performance. By adjusting the grafted monomer composition (St/MMA = 23/77) and core/shell mass ratio (70/30), we fabricate an MABS resin exhibiting an exceptional combination of properties: a high transmittance of 91.6%, a low haze of 2.7%, an impact strength of 166 J/m, and a tensile strength of 45 MPa.