Nylon Brill transition

Many aliphatic poly(amides), more commonly known as nylons, exhibit an unusual phase transition below their melting point. First noted by Brill [122], the phenomenon has been studied extensively [128-131]. It is observed for instance in nylon (6,6) at a temperature of about 210°C, when the stable low-temperature triclinic oc phase of the crystalline polymer changes to a pseudo-hexagonal phase. 

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