Synergistic phenomena in polymer photostabilization

V. Ya. Shlyapintokh
1983 Pure and Applied Chemistry  
Investigation of the synergism between tJV-absor-bers (tWA) and antioxidants (A) for photostabilization of polydiene.s and PP has revealed that synergism can be attri-. buted to diffusion of A from the deeper-.lying layers of polyiner, protected from the action of light by UVA, towards surface layers where the photoreaction takes place. With PP, where additives are irregularly distributed in the amorphous phase, the mixture of the same stabilizers may lead to a synerism effect due to TWA
more » ... ng the excited electronic state of A, suppressing its photoinitiating effect. Also conidered is the synergism attributed to an increase in solubility and a change in stabilizers distribution pattern through introduction of low-molecular weight stabilizing or non-stabilizing additives into polymers. A study of A light protective function in the absence of UVA revealed that A according to their influence on the induction period of photooxidation (Tind) can be divided into groups by their absorption and photochemical activities. Typical experimental relationships between Tind and A for different groups of A are explained.
doi:10.1351/pac198355101661 fatcat:plnh5bkqv5allm6xykhfazvriq