【摘 要】
：
Starting with the L- and D,L-lactide copolymer (L:DL = 9:1) [P(L-DL)LA] of Mw = 32.1 × 104, rods were obtained through a two stage process: (1) melt-extrusion
【机 构】
：
Institute of Polymer Chemistry
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Starting with the L- and D,L-lactide copolymer (L:DL = 9:1) [P(L-DL)LA] of Mw = 32.1 × 104, rods were obtained through a two stage process: (1) melt-extrusion at 155℃, and (2) hot-drawing at 90℃ to various drawing ratios. The molecular weight of P(L-DL)LA fell to 9.3 × 104 as a consequence of the production process. The crystallization and molecular orientation of P(L-DL)LA developed as a result of the hot-drawing. The mechanical strengths of the rods increase with the drawing ratio. The maximum for tensile strength, bending strength, bending modulus, and shear strength are 329 Mpa, 237 Mpa, 8.8 Gpa, and 157 Mpa, respectively.``
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