The polymerization reactions of monomers such as styrene and methyl methacrylate using phthalyl polyperoxide (PPO) as an initiator in the absence or presence of carbon black have been examined in comparison with those of benzoyl peroxide. Using a polystyrene prepared at 45°C in bulk with PPO, the determination of the molecular weight of the polymer has also been carried out by viscosity measurement in comparison with that of the saponified polymer. Moreover, the amounts of peroxide combined with polystyrene have been determined.
As the result, it was found that a decrease in molecular weight of polystyrene caused by the saponification is not remarkable. Although it is generally believed that PPO is decomposed to give diradicals, it may be concluded that the active site formed by the decomposition of peroxide link takes mainly the form of monoradical to initiate polymerization and most initiator fragments exist at the end of the polymer. Furthermore, in the presence of carbon black, it was found that growing polymer radical formed during the polymerization reaction attaches itself to the carbon surface and no carbon-gel is formed.

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After the thermal degradation of polyether based urethane-foam prepared with polyether polyol and toluene diisocyanate (TDI) in diethylene glycol (DEG) at 200°C, analyses were made on the compositions of the viscous liquid and the gas generated in this process.
Starting material polyol recovered by the transesterification (supposedly the main reaction) and DEG consumed in the same reaction were determined by gaschromatography. TDI-DEG adduct (1:2 mole ratio) formed at the same time was identified by thin-layer chromatography.
It was found that, although diethanol amine used as amine catalyst raised the recovery rate of polyol, it enhanced side-reactions, thereby increasing the amount of by-products, i, e, carbon dioxide and amines.
It was also found that the air flow more enhanced side reactions than the nitrogen flow.

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