Laser irradiation effects on the thermal and structural properties of PM-555 nuclear track detector

The effect of infrared pulsated laser on the thermal and structural properties of copolymers of methacrylic esters and olefins, PM-555 solid state nuclear track detector (SSNTD) was investigated. Non-isothermal studies were carried out using thermogravimetric analysis (TGA) to obtain the thermal activation energy of decomposition for PM-555 detector. The results of TGA indicate that the PM-555 samples decompose in two main breakdown stages. Samples from 300 μ m thickness sheets were exposed to laser pulses in the dose range 0.5-15 J/cm2 . The variation of transition temperatures with the laser dose has been determined using differential thermal analysis (DTA). The results indicate that the irradiation with laser in the dose range 5.1-15 J/cm2 decreases the melting temperature of the PM-555 samples and this is most suitable for applications requiring the molding of this polymer at lower temperatures. In addition, structural property studies using x-ray diffraction measurements were performed on the non irradiated and irradiated PM-555 samples.the results indicate that the absorbance and the degree of ordering of PM-555 polymer are dependent on the laser energy fluence