| Abstract
| - This is the first report on the analysis of random block polysulfide copolymers containingdifferent amounts of repeating units in the copolymer backbone, which has been studied by direct pyrolysismass spectrometry (DPMS) and by pyrolysis−gas chromatography/mass spectrometry (Py−GC/MS). Thehomopolymers such as poly(ethylene sulfide) (PES), poly(styrene sulfide) (PSS), and two randomcopolymers, viz., poly(ethylene sulfidex-co-styrene sulfidey) [copolymer I (x = y = 0.5) and copolymer II (x= 0.74, y = 0.26)] were investigated by both DPMS and Py−GC/MS (except copolymer II) techniques. Inthe case of copolymer I, the thermal degradation products of SE1, SE2, S2, and S2E (S = styrene sulfide,E = ethylene sulfide) were detected in DPMS, whereas the formation of SE1 and SE2 were observed byPy−GC/MS technique. However, for copolymer II, SE3 was also found along with SE1, SE2, S2, and S2Ein DPMS. The formation of additional product (SE3) observed in copolymer II could be due to an increasein the block length formed during copolymerization. Further, a comparative study on thermal degradationof PES, poly(ethylene disulfide) (PEDS), and poly(ethylene tetrasulfide) (PETS) were investigated byPy−GC/MS. The pyrolysis products detected by both DPMS and Py−GC/MS indicates that the thermaldecomposition of these polymers yield cyclic sulfides through an intramolecular exchange or by backbitingprocesses. The linear products with thiol and vinyl groups were also observed by Py−GC/MS along withthe cyclic products via carbon hydrogen transfer reaction.
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