Crystal forms of nylon 10 12 crystallized from melt and after solution casting

Nylon 10 12 samples prepared under different conditions, melt-crystallized, meta-cresol and trifluoroacetic acid cast, were studied by Fourier transform-infrared and wide angle X-ray diffraction. It was found that crystal forms are dependent on the approaches of sample preparation: α-form and γ-form crystals grown from melt-crystallized and trifluoroacetic acid solution cast samples, respectively. When meta-cresol cast was used, different crystal forms (including α-form, γ-form and the two forms mixture) can be obtained with different cast temperature.