The bottom layer of the microparticles would crumble intofine
powder when pressed by hand and could be dissolved into
ethyl acetate as a clear solution, showing no sign of CNF
presence. The PDLLA-CNF sheets were removed from the
cakes and were compression-molded using stainless-steel
picture-frame molds (1.4 mm thick) on a Carver Laboratory
Press (Carver Inc., Wabash, IN) at 105°C and 90 psi (0.6
MPa). Three composites were prepared. Their actual weight
contents were calculated to be 8, 15, and 32% by dividing the
dry weight of the loaded CNF by the weight of the molded
composites. The 8 and 15 wt % samples were prepared by
molding six andfive layers of sheets stacked together. Because a
higher CNF content led to a higher amount of microparticles
retained in the cellulose gel formed during thefiltration and, in
turn, a thicker PDLLA-CNF sheet obtained, the 32 wt %
composite was molded from just one sheet. A control sample
was made byfiltering a PDLLA suspension and compression
molding using the same procedure.