[[PHI].sub.CS] is the real weight percent of CS in PBCSs. The molecular weights of a CS unit and a BS unit are 226 and 172, respectively.
PBCSs granules were placed between two aluminum Hat molds at I40[degrees]C and compressed for 2 min to produce a thin sheet with 0.5 mm in thickness, and then they were quickly cooled to room temperature by the water circulation in the compression mold.
XRD was used to measure the crystalline structures of PBCSs at room temperature.
Figure 2 shows stress-strain curves of PBS, PCS, and PBCSs, which were subjected to a crosshead speed of 5 mm/ min.