2017 Annual Meeting

(196ac) Role of Compatibilizer in 3D Printed Objects

Authors

Spreeman, M. - Presenter, Tennessee Technological University
Stretz, H. A., Tennessee Technological University
Over the past twenty years, 3D printing has made strides from purely the interests of hobbyists and inventors to the mainstream of industrial and commercial interests. This is because of additive manufacturing’s allowance of customization, and it has spurred large grants and funding to improve the technology towards scaling for industrial use and production. The present research examines the mechanical properties of 3D printed parts, asking what is the process for knowing which materials and properties provide the best properties for scaling up to Big Area Additive Manufacturing (BAAM) developed at Oak Ridge National Lab (ORNL). Acrylonitrile-Butadiene-Styrene (ABS) and nylon are two common printing materials in the world of 3D printing, and the addition of Styrene-Maleic-Anhydride (SMA) to the ABS can compatibilized the blend. Blends and their controls were tested as ASTM D638 dogbones printed on a Makerbot Replicator 2X (small scale) in two separate orientations. Tensile testing of the small-scale samples showed that 5% (w/w) mixture of SMA in ABS compounded with a 60% nylon 40% ABS (w/w) showed a 60% increase in break strength in the x-axis versus ABS alone. The modulus of the 5% (w/w) mixture had increased by 68% over Nylon and 8% over ABS printed in the same orientation. BAAM-scale tests were done as ASTM D6272, printed at ORNL’s Blue Gantry. Initial tests have shown 76% improvement in the Z/X ratios of nylon in break strength with addition of ABS/SMA compatibilization mixtures. The breaking strength of the x-orientation 4-point bend samples were not statistically different between the 3 materials. The samples’ break surface from 4-point bend analysis were analyzed by photomicrograph using ImageJ image analysis software. Analysis of the surfaces showed that the addition of a compatbilizer reduced the void space by 53% in the x-orientation samples and 83% in the z-orientation samples. Based on the observed results, there appears to be a positive correlation between the addition of a compatibilizing agent and improvement in the z-orientation breaking strength.