54
V. Demchenko et al.
Fig. 3.2 Wide-angle X-ray
diffractograms of (1) the
IPEC pectin–P4VP, (2) the
IMC pectin–Ag + –P4VP, and
(3) the IPEC–Ag
nanocomposite
10
20
30
40
50
0
2
4
6
11.0
o
(200)
(111)
3
2
1
~
I, rel. units.
2q, deg
The revealed peculiarities and changes in structures while transiting from the
IPEC to IMC and IPEC–Ag nanocomposites form the basis for the further study of
their structural heterogeneity.
Analyzing the profiles of small-angle X-ray scattering of the polymer systems,
presented in [19, 20], as dependences of ˜
I on q (Fig. 3.3) and s 3 ˜
I on s 3 , where ˜
I is the
intensity of scattering without the collimation correction and q = (4π/λ)sinθ = 2πs,
all these systems have heterogeneous structure, i.e., contrast electron densities ρ
(ρ = ρ–<ρ>, where ρ and <ρ> are the local and average values of the electron
density, respectively) are present in their volumes. This result means that in the
IPEC, IMC, and the nanocomposites based on the IPEC and Ag, there are at
least two types of regions of heterogeneity with different values of local electron
density ρ.
As one can see, scattering intensity and thus ρ value are increasing for
these systems in the following rank: IPEC pectin P4VP → IMC pectin–Ag + –
P4VP → nanocomposite IPEC–Ag (Fig. 3.3, curves 1–3). However, the absence of
the interference peak in the all profiles indicates the stochastic nature of the location
of various types of heterogeneity areas in a space.
In order to assess semi-quantitatively the value of the relative level of structural
heterogeneity of these polymer systems, their Porod invariants Q were compared [21]:
Q
=
∞
0
q ˜
I (q)dq,
V. Demchenko et al.
Fig. 3.2 Wide-angle X-ray
diffractograms of (1) the
IPEC pectin–P4VP, (2) the
IMC pectin–Ag + –P4VP, and
(3) the IPEC–Ag
nanocomposite
10
20
30
40
50
0
2
4
6
11.0
o
(200)
(111)
3
2
1
~
I, rel. units.
2q, deg
The revealed peculiarities and changes in structures while transiting from the
IPEC to IMC and IPEC–Ag nanocomposites form the basis for the further study of
their structural heterogeneity.
Analyzing the profiles of small-angle X-ray scattering of the polymer systems,
presented in [19, 20], as dependences of ˜
I on q (Fig. 3.3) and s 3 ˜
I on s 3 , where ˜
I is the
intensity of scattering without the collimation correction and q = (4π/λ)sinθ = 2πs,
all these systems have heterogeneous structure, i.e., contrast electron densities ρ
(ρ = ρ–<ρ>, where ρ and <ρ> are the local and average values of the electron
density, respectively) are present in their volumes. This result means that in the
IPEC, IMC, and the nanocomposites based on the IPEC and Ag, there are at
least two types of regions of heterogeneity with different values of local electron
density ρ.
As one can see, scattering intensity and thus ρ value are increasing for
these systems in the following rank: IPEC pectin P4VP → IMC pectin–Ag + –
P4VP → nanocomposite IPEC–Ag (Fig. 3.3, curves 1–3). However, the absence of
the interference peak in the all profiles indicates the stochastic nature of the location
of various types of heterogeneity areas in a space.
In order to assess semi-quantitatively the value of the relative level of structural
heterogeneity of these polymer systems, their Porod invariants Q were compared [21]:
Q
=
∞
0
q ˜
I (q)dq,