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The Effect of Plastic Deformation under High Pressure on the Thermal Effects in Polyacrylamide

“…The processes Figure 3. The dependences of the enthalpies (∆H) of hightemperature (1)(2)(3) and low-temperature (4)(5)(6) peaks on the anvil turn angle (α) for different polyacrylamide specimens deformed under a pressure of 1 GPa: 1, 4 -thermal specimen; 2, 5 -solid-phase specimen; 3, 6 -radical specimen © 2016 Smithers Information Ltd. T/23 occurring in the dielectric material should depend on the state of the plates of this capacitor, which can be either ground (which will promote charge draining) or insulated. All results set out earlier were obtained during the deformation of specimens on ground anvils.…”

“…In the process of plastic deformation under high pressure, carried out on a high-pressure apparatus of the Bridgman anvil type, the crystalline phase of amorphous-crystalline polyethylene and polypropylene breaks down to an ultradisperse state, when the size of the regions of coherent scattering amount to several nanometres [1,2]. Along with rearrangement of the crystalline phase, considerable changes were also found in the amorphous phase of the polyolefins.…”

“…In Zhorin [6] it was established that the flow stress of polyacrylamide obtained in solid phase is more than 30% higher than that of a polymer produced by radical liquid-phase polymerisation. In Zhorin et al [7] it was established that the enthalpy of dissolution of the solid-phase polymer depends strongly not only on the pressure under which the polymer was produced but also on the degree of conversion of the monomer during polymerisation. Thus, the properties of the polymer, determined by intermolecular interaction, depend considerably on the way in which the polymer is produced.…”