Crystal structure, conformation and morphology of solution-spun poly(L-lactide) fibers

摘要: Depending on the spinning and drawing conditions, two crystal structures for solution-spun poly (L-lactide) are obtained. The pseudoorthorhombic a structure (a= 10.6, b= 6.1, and c= 28.8 A) con-tains two chains in the unit cell and is found at relatively low drawing temperatures and/or low hot-draw ratios. At higher drawing temperatures and/or higher hot-draw ratios a second so-called 0 structure appears. For this structure an orthorhombic unit cell is proposed (a= 10.31, b= 18.21, and c= 9.00 A) containing six chains. The chain …