抄録
An attempt was made to elucidate the effects of an anionic surfactant, sodium dodecyl sulfate (SDS), on the fine structure and mechanical properties of Nylon-6 films heat treated or stretched uniaxially in the surfactant aqueous solutions.
Sample films were unoriented low crystalline Nylon-6 film and those uniaxially stretched under free width by dry-process at 120°C. The concentrations of SDS solutions were 0-0.30 wt. %.
The wet-mechanical properties of the films heat treated in SDS aqueous solutions, such as tensile strength, elongation at break and Young's modulus, were measured in the same solutions at the same temperature. The dynamic viscoelasticity, i.e. the temperature dependencies of dynamic loss modulus E″ and dynamic loss tangent tan δ, were measured at 100Hz using a Viscoelastic Junior Spectrometer. The relation between the crystallization of the film and the addition of surfactantwas investigated by comparing densities and X-ray diffraction patterns. The molecular orientation was studied by measurements of birefringence and X-ray diffraction.
The following results were obtained;
(1) The addition of SDS in the wet-process lowered the wet-mechanical properties of unoriented low crystalline Nylon-6 film.
(2) SDS promoted the diffusion of water into the amorphous region of Nylon-6 film, and suppressed the growth of the crystallite size in the crystallization by the heat-treatment.
