Crystallization from the melt of trans-l,4-polyisoprene was followed using Fourier-transform infra-red spectroscopy. The spectral subtraction factor versus time was obtained at the crystallization temperature and after cooling to 25°C for fractions and for the parent material. Crystallization of the/? crystal form was followed at 36 and 43°C and of the ~ form at 43 and 51 °C. Samples crystallized at 25°C and subsequently annealed at 43°C were also monitored. The amorphous fraction for prenucleated melt-crystallized :~-form-containing samples increased with molecular weight at the crystallization temperature and after cooling to 25°C. Samples containing the /~ crystal form showed a molecular-weight dependence at a crystallization/annealing temperature of 43°C that disappears upon cooling the sample to 25°C. The results are discussed in terms of lamellar surface disorder and lamellar thickness distribution.
Посилання на статтю:
Infra-red spectroscopic investigation of bulk-crystallized trans-l,4-polyisoprene / Nadarajah Vasanthan, Joseph P. Corrigan and Arthur E. Woodward* // Polymer. – 1993. – Vol 34. – P. 2270-2276.