Decomposition of Peroxides in Polystyrene and Some Solid Arenes

Abstract

ABSTRACT:In order to cinnamoyloxylate polystyrene, cinnamoyl peroxide was decomposed in polystyrene film. The rates and products of the decomposition were determined. Products were cinnamoyloxypolystyrene, cinnamic acid, and a mixture of cinnamic acid esters (mainly styryl cinnamate). It was found that 0.11 mol cinnamoyloxy group per mol of cinnamoyl peroxide was attached to the polystyrene nuclei. The results were compared with those for the decomposition of benzoyl peroxide in polystyrene. The rates of decomposition of peroxides in some solid aromatics were then studied. The decompositions in solid biphenyl were slow, but those in phenanthrene were very fast. The results were interpreted in terms of the ionization potentials of the aromatics.KEY WORDS Cinnamoyl Peroxide I Benzoyl Peroxide 1 Polystyrene I Decomposition in Solids I Cinnamoyl groups are light-sensitive, and the introduction of Ph-CH=CH-COO-groups into polystyrene is of interest since the polymers thus formed are expected to cross-link upon irradiation with light. A convenient method for the introduction of cinnamoyloxy groups into polystyrene appeared to be the decomposition of cinnamoyl peroxide in polystyrene. Such an investigation has been carried out, and the results are described in this paper. Decompositions of benzoyl peroxide in polystyrene, phenanthrene and biphenyl have also been investigated, and the results are compared. EXPERIMENTAL MaterialsPolystyrene was prepared by the emulsion polymerization of styrene at looc with a redox system of polyamine-iron-hydroperoxide. 1 Viscosity-average molecular weight was 126,000.Cinnamoyl peroxide was prepared by the method described by Sana, Nandi, and Palit. [P 0] are the concentrations of peroxide at time t and time 0), the plots were on a straight line at least until 50-% decomposition. Haas determined the rates of decomposition of benzoyl peroxide in polystyrene films by iodometry, 3 and then by infrared spectrophotometry, 4 and the results of the two methods were in fair agreement. The rates of decomposition of many peroxides yielding some acids and esters as products were determined by infrared spectrophotometry. 5

Fluorescence sensing of microcracks based on cycloreversion of a dimeric anthracene moiety

“…It was reported that BPO decomposes below 100 C in the film and the rate and product of decomposition vary depending on the structure of the matrix material. 32 In this study, a transparent film of Poly-AC (or Poly-AA) containing BPO was prepared and subjected to heating at 85 C for 4 h in an oven. After the thermal treatment of the film, BPO almost decomposed (see Fig.…”