Changes in the structure of polymethyl methacrylate caused by irradiation with millisecond laser pulses

Changes in the molecular structure of polymethyl methacrylate caused by irradiation with laser pulses of different powers were investigated by x-ray diffractometry methods. An analysis was made of the position and half- width of a halo in x-ray diffractograms. Coherent scattering regions and the distributions of the moduli of the interatomic vectors were determined. Action of laser radiation on this transparent dielectric induced molecular structure changes associated with an increase in the molecular order in the amorphous matrix and with the formation of clusters at certain specific laser radiation energies.