INVARIANCE OF LONG SPACING-CRYSTALLIZATION TEMPERATURE-DEPENDENCE OF POLYAMIDES PRECIPITATED FROM SOLUTION

The authors reexamined the lamellar thickness of solution-grown polyamide (nylon 6. 6) crystals in relation to crystallization conditions, with crystallization temperature T//c as the main variable. Over a very wide range of T//c the lamellar thickness was invariant; a notable increase could be produced only at the highest T//c. The existence of this minimum invariant value raises important questions concerning the applicability of the current kinetic theories over such a wide range of supercoolings. Several other polyamides also revealed invariant long spacings after crystallization from solution.