Photodegradation of rigid PVC formulations. II. Spectral sensitivity to light‐induced yellowing by polychromatic light

Abstract

SynopsisT h e wavelength sensitivity of a compounded extruded rigid poly(viny1 chloride) formulation t o yellowing under exposure t o filtered xenon radiation is determined using a cut-on filter technique. Spectral sensitivity of the formulation in the absence and the presence of 2.5 phr of rutile titanium dioxide was examined, and the results were compared t o those previously reported for the yellowing of an identical vinyl formulation exposed to monochromatic light. Maximum in the activated spectrum for yellowing under exposure to filtered xenon radiation was found t o be in the wavelength region 300-320 nm for both types of samples. The results agreed qualitatively with those previously obtained in the study of the same material exposed to monochromatic light.

Photostabilizing Efficiency of Poly(vinyl chloride) in the Presence of Organotin(IV) Complexes as Photostabilizers

“…The IR spectrum of irradiated PVC shows three absorption bands due to formation of carbonyl, polyene and hydroxyl groups. These bands resonate at 1772 (C=O), 1604 (C=C) and 3500 cm −1 (OH), respectively [38]. The growth rate of such peaks related to a reference peak (1328 cm −1 ) could be considered as a measure for the photodegrading of PVC.…”

Photostabilizing Efficiency of PVC in the Presence of Schiff Bases as Photostabilizers

“…Polyvinyl chloride is the third-most widely produced synthetic plastic polymer after polyethylene and polypropylene and is widely used in several industries, including architecture, electronic, chemical engineering, packaging, and transportation [1][2][3][4]. However, the low photostability of PVC leads to hydrogen chloride loss, discoloration, and serious corrosion phenomena, accompanied by changes in the physical and chemical properties of PVC.…”

UV-induced acid–base chemistry within the PVC matrix

“…An equal amount of work has concentrated on understanding the mechanism of the process, where possibilities of (i) a radical, (ii) an ionic and (iii) an autocatalytic process have been discussed [6][7][8][9]. Photodegradation and photochemical modifications of PVC and the resulting polyenes have also been extensively studied for improving electrical conductivity of the films [10][11][12]. It was even claimed that dehydrochlorinated PVC gave polyacetylene-like material [13].…”