ポリL-乳酸の固有複屈折度 Intrinsic Birefringence of Poly (L-lactic acid)
The intrinsic birefringence value of Poly (L-lactic acid) was estimated experimentally for the drawn and annealed fiber, in which almost all of the crystals involved are the a-form. The value 0.030 - 0.033 was obtained using Stein's formula by substituting the results of structural analysis for highly drawn and annealed samples. The extrapolated value 0.030 was also obtained by assuming the affine deformation. On the other hand, as the intrinsic birefringence value of the a-form crystal, -0.013 was also obtained by summation of bond polarizability using crystal structure data. The experimental value is more believable because the contribution of convalent bond alone was included in the calculation.
繊維学会誌 55(1), 21-27, 1999-01-10