Orientational order in polymer surface layers

Mechanisms of heat transfer on polyvinylchloride and poly(vinyl butyral)

“…This is due to the fact that the number of structural elements that reach an energy level sufficient for rupture of bonds with neighboring particles and for diffusion migration to the surroundings of other kinetic elements increases as a consequence of fluctuation processes [15]. However, the nature of fluctuation processes in block flexible-chain polymers has not been completely investigated [18]. At the same time, we emphasize that a few mechanisms of energy transfer have already been studied in condensed media: electron, photon, phonon, exciton, resonance, and other mechanisms [19].…”

“…The mechanism of heat transfer in this case is fundamentally different from those considered above, since it characterizes the total effect of interaction between phonons and photons [4]. There are several forms of it, such as infrared interaction (the photon gives rise to a transverse optical phonon) [8], optical interaction (photon scattering in the region of optical frequency interval) [9], x-ray interaction (structural x-ray scattering) [1], γ radiation [21], neutron interaction [18], and others [31]. In these cases the unusual behavior of polymers manifests itself in the fact that the structural elements of a substance can be excited in a certain region of actions of energy fields [29].…”

“…It has been established [17] that in the range of small γ lat values, the major contribution to λ is made by phonons, whereas the most probable configuration of polymeric structure formations is an extended chain [13]. The diffusion mechanism of heat transfer is predominant when 2 < γ t < 6 (8 < γ lat < 14) [18]. The quantity γ n is evaluated from experimental data [9] as…”

“…Interpreting the diffusion of the excited atoms (H, C, Cl) as the result of their jumps to a distance equal to the intrinsic effective diameter a i [27] over the period τ = τ 0 exp (A i ⁄ kT), we determine ∂M i ⁄ ∂T from Eq. (18). The carried-out investigations show that in the case of H atoms the value of v i is equal to 2.0⋅10 3 m⋅s −1 .…”

Orientational order and evolution of the properties of biomolecules in anisotropic media

“…For statistically uniaxial macromolecules with the longitudinal axis l, the tensor γ is characterized by the longitudinal (γ l ) and transverse (γ t ) components or by the mean value = (γ l + 2γ t )/3 and anisotropy Δγ = γ l -γ t . For bio molecules in anisotropic media, and Δγ were deter mined using the quantity [8,9] (1) for (where = (ε || + 2ε ⊥ )/3), isotropic tensor f V = ( + 2)/3 [8,9], or components L j = 1/3 [10,11]. These models predetermine and Δγ values and are responsible for unphysical consequences from spectral data [5].…”