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A D V A N C E D M A T E R I A L S & P R O C E S S E S | F E B R U A R Y / M A R C H 2 0 1 9 2 5 and pestle. The powders were then sieved and the particles with -325 mesh size were stored in a plastic bag for fur- ther characterization. True density ( ρ T ) of the powders was determined by He pycnometer (Ultrapyc 1200e, Quanto- chrome Instruments, Boynton Beach, Fla.). For microscopy analysis, a small amount of dried and sieved pow- ders was studied. In addition, a small amount of dried and sieved powders was poured in the acetone media (ace- tone >99.9%, Sigma Aldrich). The result- ing suspension was sonicated (Branson 2800, Branson Ultrasonics, Danbury, Conn.) for 1 h. A few drops were also collected for microscopy analysis. A Rigaku diffractometer (Smart- Lab, Rigaku, Japan) was used for all XRD measurements at a scan rate of 4 o /min from 20 o to 50 o . A JEOL JSM- 6490LV scanning electron microscope (JEOL USA, Peabody, Mass.) was used to obtain secondary electron (SE) and backscattered electron (BSE) images of the synthesized MoAlB particulates. X-ray information was obtained via a thermo nanotrace energy dispersive x-ray detector with an NSS-300e acqui- sition engine [13] . All other images were taken by field emission scanning elec- tron microscope (FESEM) in SE and BSE mode by a JEOL JSM-7600F scanning electron microscope (JEOL USA). Ener- gy-dispersive spectroscopy information was acquired by using an UltraDry sili- con drift x-ray detector and NSS-212e NORAN System 7 x-ray microanalysis system (Thermo Fisher Scientific, Mad- ison, Wis.). An average of three EDS re- sults are reported for determining the chemical composition of a location based on the uniformity of the region in BSE. Note that this region represents a uniform microconstituent and it is not implied that it is a single phase. In addi- tion, it is difficult to quantify B by EDS, hence it is reported as B x . The theoretical densities of cel- lulose acetate (1.3 g/cc, average M n ~30,000, Sigma Aldrich) and ρ T of PE MoAlB particulates were used to cal- culate 0.5, 1, and 2 vol% PE MoAlB in cellulose acetate composites. For each composition, the calculated amount of PE MoAlB was poured into ~17.75 g of acetone (0.79 g/cc) in glass vials. The mixture was sonicated for 1 h. The cal- culated amount of CA was then poured into the glass vials. The slurry was mixed by a magnetic stirrer with a Tef- lon-coated stir bar for 24 h; thereaf- ter, ~4 g of suspension was poured in a Fig. 4 — Tensile stress versus displacement of CA composites with (a) 0.5 vol%; (b) 1 vol%; and (c) 2 vol%MoAlB based additives; and (d) summary of tensile strength of all composites designed in this study. (a) (b) (c) (d)