Effect of thermomechanical impacts on the deformation of thin polyimide films at uniaxial tension

Thermomechanical studies of the dependence of deformation on time (t) and temperature (T) for various static stresses in polyimide under uniaxial tension were carried out. Temporal deformation curves for static stresses in the range from 75 to 110 MPa consist of two stages: 1 - increase; 2 - exit to saturation, which is associated with a change in the nature of structural transformations of macromolecules, due to the action of the static stresses. An increase in temperature and voltage leads to an increase in the dependence e (Т). This is due to the intensification of the processes of structuring macromolecules with increasing temperature and are supplemented by processes of breaking bonds between macromolecules, which increase the strain rate. Experimental data are described in terms of exponential and linear models

Investigation of Mechanical Properties of Polyimide- Polyethyl-eneterephthalate System

The study of the physico-mechanical properties of new composite materials based on polyimide (PI) and polyethyleneterephthalate (PET) was carried out. Dependences of σ from ε for different concentrations of the second component and irradiation doses were measured. The experimental data are described satisfactorily by the exponential cascadeprobabilistic model

Catastrophic models of materials destruction

The effect of concentration and type of fillers on mechanical properties of composite material based on polyimide were studied. Polyethylene terephthalate (PET, polyester), polycarbonate (PCAR) and montmorillonite (MM) were used as the fillers. The samples were prepared by mechanically blending the polyimide-based lacquer solutions with different concentrations of the second component. The concentration of filler and its class, especially their internal structure and technology of synthesis determine features of physical and mechanical properties of obtained materials. Models of catastrophic failure of material satisfactorily describe the main features depending on tension ct from deformation e

Study of the influence of the electron irradiation dose on the deformation of Mylar films taking into account the processes of destruction and crosslinking

Experimental studies of the dependence of the deformation [epsilon] on the dose of electron irradiation D taking into account the processes of destruction and crosslinking for films of the Mylar type have been carried out. It was obtained that the dependence of [epsilon] on D for the process of cross-linking is described by a linear and destruction by an exponential function

Study of the influence of the electron irradiation dose on the deformation of Mylar films taking into account the processes of destruction and crosslinking

Experimental studies of the dependence of the deformation [epsilon] on the dose of electron irradiation D taking into account the processes of destruction and crosslinking for films of the Mylar type have been carried out. It was obtained that the dependence of [epsilon] on D for the process of cross-linking is described by a linear and destruction by an exponential function