摘要：

It has been reported that there is a special side chain—side chain interaction between the right-handed and left-handed α-helices in the racemic mixture of poly(γ-benzyl glutamate). In this paper physical properties of mixtures of poly(γ-benzyl-L-glutamate) and poly(γ-benzyl-D-glutamate) are studied. From X-ray diffraction measurements, the reflection characteristic of the regular arrangement of the benzyl group at the end of the side chain was shown to disappear on heating at 97°C and to appear on cooling at 73°C. This reversible change was also observed in viscoelastic, thermal and dilatometric measurements and was ascribed to the breakdown and formation of stacks of benzene rings. In the case of samples cast from benzene solution, it was found that the formation of stacks is hampered by the preferable super helix formation.

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