Effect of the Ratio of Components in a Polyvinyl Alcohol-Chitosan Composite on the Temperature Range of its Inelasticity

α-Relaxation and Temperature–Frequency Inelasticity of the Polyvinyl Alcohol–Chitosan Composite

“…1b) in the region of α-relaxation in the system is characterized by an anomaly of various intensities in different temperature ranges. This anomaly is described as the defect of the modulus, which is determined by the range of the squares of the frequencies [16]. The changes in these characteristics of the studied samples (Table 1; Fig.…”

“…The changes in these characteristics of the studied samples (Table 1; Fig. 3) were calculated according to a procedure of calculating the physicochemical characteristics of relaxation processes, which manifest themselves as the peak of the dissipative loss in the spectrum [16]. For a qualitative analysis of the change in continuous relaxation time spectrum H(τ), it should be taken into account that any dissipative process of the relaxation nature is a local (in temperature manifestation in the mode of free damped torsional vibrations) inelasticity process, which gives rise to a positive defect ΔG of the shear modulus [19].…”

“…The use of the Maxwell function in the dynamic modes of external deforming actions was theoretically analyzed previously [16,24,25].…”

“…At temperatures T < T = 43°C, the main relaxing elements are PVA segments and, at T > 43°C, they are CS elements; i.e., the structural complex is a system of two interpenetrating noninteracting structural subsystems (components) in the bulk of the composite. A gradual change in the ratio between them [16] leads to a mutual reversible transition of the subsystems to the matrix and the support.…”

“…The PVA-CS composite system, in which the ratio between the components can vary from 0 to 100%, was reported [16] to be a promising system to produce biomedical materials. One of the conditions of using these materials is the possibility to obtain materials with different rigidities, i.e., with certain temperature ranges of the inelastic response to an external deforming action in both static and dynamic modes.…”