The degradation of unstabilised and HAS-stabilised polystyrene (PS) films is described. The films have been exposed to accelerated weathering in a Xenotest Alpha apparatus to mimic outdoor conditions ( 300nm). Fourier transform infrared spectroscopy (FT-IR) and gel permeation chromatography (GPC) have been used to investigate the changes of the chemical structure and X-ray-photoelectron spectroscopy (XPS) to study the surface photo-oxidation. Mechanical properties (i.e. stress at the breaking point (b), strain at the breaking point (b)) were found to be very sensitive to the degree of surface oxidation. The stabilising action of the HAS interested both the bulk and the surface.
|Titolo:||A study on chemical modifications, mechanical properties and surface photooxidation of films of polystyrene (PS) stabilized by hindered amines(HAS)|
|Data di pubblicazione:||2004|
|Appare nelle tipologie:||1.1 Articolo in rivista|