Chemistry Reference
In-Depth Information
X-ray analysis of the films was carried out using transmission tech-
nique with a diffractometer Bruker Advance D8 (Cu Kα). IR spectra of
deuterated films were recorded on a spectrophotometer Bruker IFS 48
with a Fourier transform at a resolution of 2 cm
-1
.
2.2
X-RAY AND DSC STUDIES
In this chapter it was shown by X-ray technique (WAXS) that the original
samples of PHBV are characterized by high crystallinity. In their diffrac-
tion patterns at least 5 reflections of the orthorhombic lattice with char-
acteristics
a
= 5.74 Å,
b
= 13.24 Å and
c
= 5.98 Å were determined that
well conform with the earlier studies [11, 12]. In Fig. 2.1, the WAXS dif-
fractograms are presented as asset of curves belonging to initial PHBV
(
1
), PHBV treated by water at 40 °C (
2
), PHBV/SPEU blend with compo-
nent ratio 40/60 (
3
), the same blend treated by water at 70 °C (
4
), and the
PHBV/SPEU (60/40) blend also treated by water at 70 °C (
5
). The SPEU
presence in the system leads to an amorphous hallo in the range 22° (cf.
curves
1
and
3
), its intensity is increased with the SPEU content.
FIGURE 2.1
WAXS diffractograms for initial PHB (
1
), PHB after water treatment at
318 K (
2
), initial blend PHB-SPEU 40:60 (
3
), blend PHB-SPEU 40:60 after water treatment
at 343 K (
4
), and PHB-SPEU blend 60:40 after water treatment at 343 K.
The impact of the water medium causes noticeable changes in the crys-
tal structure, namely an increase in the crystallinity degree, the crystallite
