Dehydrochlorination of poly(vinyl chloride) modified with titanium dioxide/poly(ethylene oxide) based paint photocatalysts

Abstract

ABSTRACTThe dehydrochlorination of poly(vinyl chloride) (PVC) film samples modified with titanium dioxide (TiO2)/poly(ethylene oxide) (PEO) based paint photocatalysts [the addition of methyl linoleate (ML) or methyl oleate (MO)] was performed. After 24 h of UV photoirradiation, the sample with TiO2/PEO showed that there existed a structure with the longest polyene length, whereas that with TiO2/PEO/ML contained the most polyene structures. The chloroform‐soluble fraction of the sample with TiO2/PEO contained a poly(vinyl alcohol) (PVA) structure instead of a polyene one and showed a novel method of PVA production via PVC photodegradation. The molecular weight curve of the fraction shifted slightly to a lower molecular weight compared to that without the photocatalyst; this showed that slight polymer chain scission occurred. The 1H‐NMR and 13C‐NMR spectra showed that the content of PVA units was about 20%, and the PVA sequence was blocky. The fraction of the sample with TiO2/PEO/ML contained the highest methyl group content; this showed that the branch degree was highest as was the polyene content. These highest contents were due to the existence of the grafted ML. Pyrolysis gas chromatography/mass spectroscopy measurements suggested that there existed more polyene and graft units in the chloroform‐insoluble fractions of the samples with TiO2/PEO, TiO2/PEO/ML, and TiO2/PEO/MO, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40760.