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Melting behaviour of polytetra hydrofuran / cholesteryl palmitate blends investigated by two- dimensional infrared correlation spectroscopy

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: M. C. Popescu, C. Vasile

Editorial: Soft Materials, 8(4), p.386–, 2010.

Rezumat:

The melting behaviour and miscibility of the PTHF/CP blends, was investigated by FT-IR and generalized two-dimensional infrared (2D IR) correlation spectroscopy. Temperature-dependent spectral variations during the melting process in the C–H stretching (3100–2600 cm−1), C=O stretching (1800–1600 cm−1), and C–O–C stretching (1330–900 cm−1) bands regions were monitored. In the crystalline state, where the molecules form an ordered structure, the dipole-dipole coupling or intermolecular hydrogen bond interactions between the C=O and CH3 groups take place, which have been evidenced by crystalline band at 1715 cm-1 and it shift towards lower frequency. Data analysis during the heating process, indicates that the structural adjustment of the PTHF occurs faster than that of the CP, the former (PTHF) forming an amorphous phase more easily.

Cuvinte cheie: 2D correlation spectroscopy, semicrystalline polymers, liquid crystals, melting, blends