Preparation of Poly(Styrene-co-Acrylonitrile)-Grafted Attapulgite via Simultaneous Reverse and Normal Initiation Atom Transfer Radical Polymerization (SR&NI ATRP) and Its Effect on Polycarbonate/Acrylonitrile-Butadiene-Styrene Terpolymer Ternary Composites

To further improve the comprehensive properties of polycarbonate/acrylonitrile-butadiene-styrene terpolymer blends (PC/ABS), in this work, styrene-acrylonitrile copolymer [P(St-co-An)] was grafted on the surface of attapulgite particles (ATP) by simultaneous reverse and normal initiation ATRP (SR&NI ATRP) to yield ATP@P(St-co-An) hybrid particles. Then a series of PC/ABS/ATP@P(St-co-An) composites were prepared via the melt blending method. The effects of ATP@P(St-co-An) content on the morphological, mechanical, thermal and rheological properties of the composites were investigated in detail. The core-shell ATP@P(St-co-An) hybrid particles with the polymer layer thickness of 20-40 nm were synthesized successfully according to the results of X-ray photoelectron spectrometer (XPS), Fourier transform infrared spectrometer (FTIR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). The improvement in mechanical properties, reduced glass transition temperature (Tg) difference between PC and ABS and micromorphology changes of the composites proved the compatibilization, strengthening, and toughening effect of the ATP@P(St-co-An). Compared with the PC/ABS blend, with strength and toughness of 50.8 MPa and 56.3 kJ/m(2), when the ATP@P(St-co-An) content was 4 wt%, a reasonable balance (85.8 MPa and 86.2 kJ/m2) between strength and toughness was achieved with substantially enhanced thermal stability. Moreover, the composite showed more remarkable non-Newtonian behavior, and its processability was also improved. We believe this work provides an effective approach to optimize the compatibility and comprehensive properties of PC/ABS blends.