Abstract: The amorphous orientation of poly (glycolide2co2L2lactide) fiber with 90 :10 mole ratio of glycolide
to L2lactide (PGLA910) was studied by differential scanning calorimeter (DSC) , wide angle X2ray diffraction
(WAXD) and the sonic velocity method. The crystallization in PGLA910 came only from PGA according to the
DSC and WAXD results of the drawn and annealed fiber. The sonic modulus was computed through
determining the sonic velocity of PGLA910 fiber with crystallinity from about 5 % to 30 % , and the intrinsic
transverse modul in the amorphous region and the crystalline region were E0
t , c = 9135 GPa and E0
t , am =
3. 21 GPa respectively obtained based on the two2phase model . The amorphous orientations of 7 drawn PGLA
fibers had a linear relationship with the thermo2shrinkages and indicated the characterization was reasonable.