THE SECONDARY STRUCTURE AND MOLECULAR CHAIN ORIENTATION OF POLY-γ-METHYL- d -GLUTAMATE CAST FROM SOLUTION IN DICHLOROACETIC ACID

The β-form, which is completely free from other secondary structures, has been newly observed in the case of the solid poly-γ-methyl-d-glutamate film cast from solution in dichloroacetic acid. The a-and c-axes lie on the plane parallel to the film surface and the molecules are packed parallel with a helical twist relative to one another about the b-axis which is perpendicular to the film surface. When the solid film is stretched, the c-axis orients along the drawing direction by rotating about the b-axis, showing double orientation.