Structural Transformations in the Bulk of Polypropylene upon Plasma Treatment

Substantial changes not only on the surface but in the bulk of a polypropylene film can be induced by its treatment in a low-frequency glow discharge, direct-current discharge, and high-frequency discharge. Changes in the phase composition, an increase in crystallinity, melting point elevation, growth of the molecular mass, broadening of the molecular mass distribution, and lowering of the polymer solubility are possible. It was assumed that short-wavelength ultraviolet plasma radiation is responsible for the observed changes in the structure and molecular mass of polypropylene.