Effect of addition of finely divided radiation-crosslinked polyethylene on thermomechanical properties of polyethylene

The properties of polymer plates molded from finely divided powders prepared by cryogenic dispersion of polyethylene (PE) and radiation-crosslinked polyethylene (RPE) and the plates molded from the 1 : 1 blend of these powders were studied by thermomechanical analysis (TMA). It was shown that the strain of electron beam-irradiated PE plates in TMA, and the effective number concentration of three-dimensional network points are enhanced by increasing the radiation dose. However, increasing the pressure in the TMA of RPE produced the reverse effect on these characteristics. It was found that at a load of 0.05 MPa, the thermomechanical curve of the composite material is close to that of the initial polyethylene, and the indentation is significantly higher than follows from the additivity rule. The effective concentration of network points turned out to be three orders of magnitude smaller than in RPE.