A.N. Lachinov1, S.N. Salazkin2, I.V. Alexandrov3, R.Z. Valiev3
--------------------------------------------------------------------------------------------------------------------------------
1 Institute of Molecules and Crystal Physics, Ufa Scientific Centre of Russian Academy of Sciences, Prospekt Oktyabrya 151, Ufa , Russia;
2 Institute of Elementorganic Compounds, Russian Academy of Sciences;
3 Institute of Physics of Advanced Materials, Ufa State Aviation Technical University, 12 K. Marx St., Ufa 450000, Russia.
___________________________________
The present work demonstrates results of experimental investigation of high pressure torsion (using P(6GPa) effect on electron properties and conduction of polyphthalidyldenbiphenililene (PDF). Interest to this material is aroused by sensor effects which can be observed in this polymer because of its unusual molecular structure characterized by two energy-persistent configurations.
The pressure ranged within 1-6 GPa and shear strain varied in the interval up to 180o. Influence of the noticed effects on electron properties of polymers was studied by ultraviolet and infrared spectroscopy, electron paramagnetic resonance, X-ray structural analysis, measurements of inductivity and dielectric loss tangent, conductivity measurements.
It has been revealed that large strain work leads to appearance of essential conductivity of polymer samples. Moreover, the conductivity preserved after de-processing. Anomalous increase of inductivity and dielectric loss tangent proceeded the increase of conductivity.
Analysis of optical spectrum in infrared and ultraviolet spectrums and electron paramagnetic resonance data was performed. The data obtained enabled to identify transformation of electron subsystem of polymer samples depending on external influence value, which implies subsequent regrouping of lateral phthalide fragment being responsible for the change in electron properties of the material. This conclusion was proved by quantum-chemical calculations of polymer structure.
The data obtained were compared with experimental results on deformation of polymethylmethacrylate and epoxide resin in case of high shear strain.
The present report suggests detailed discussions of transformation mechanisms of polymers electron structure and possibility to use the revealed effect of anomalous conductivity in sensor devices.
|