Role of compatibilizer in 3D printing of polymer blends

Abstract

For additive manufacturing interfacial adhesion (bead-bead) remains an important issue affecting uniformity of mechanical properties. The present work examined the role a compatibilizer would play when used in fused filament fabrication (FFF) printing. Poly(styrene-maleic anhydride) (SMA) compatiblizer was mixed in varying compositions in blends of polyamide/poly(acrylonitrile-butadiene-styrene) (PA/ABS) to improve interfacial adhesion. Both small and large-scale 3-D component properties were examined. The mechanical property anisotropy ratio, an indication of bead-bead adhesive strength (defined as a property measured along the z axis versus the x axis) is representative of adhesive strength. Large-scale (big area additive manufacturing, BAAM) tests (flexural properties) showed 62% improvement in the anisotropy ratio for modulus, 77% improvement in the anisotropy ratio of the strength, 56% improvement in the anisotropy ratio of elongation at break, and 55% improvement of the anisotropy ratio of the Charpy impact strength over the control PA values. Thus, use of compatibilized polymer blends can provide customized materials without the need for new chemistry. Addition of maleic anhydride-compatibilized ABS improved PA blend bead-bead adhesion.