Formation of spherulities in polyamides. IV. Even–odd polyamides and poly(ω‐aminocarboxylic acids)

Isothermal and nonisothermal spherulitic crystallization in even–odd and poly(ω‐aminocarboxylic acids) has been studied for a range of fusion conditions and solidification temperatures. The variety of spherulites so formed are classified mainly by optical microscopy. It is found that polyamides with similar types of repeat units generally exhibit similar morphological features under corresponding crystallization conditions. The basic patterns are illustrated in the text. Changes in spherulitic birefringence with temperature are also discussed. In some cases, at temperatures not far below the polymer melting point, platelet‐like crystalline aggregates are formed in thin film preparations. These platelets exhibit properties characteristic of single crystals.