Initiation of the polymerization of alkenylaromatic monomers in the 120–200°c fraction of tars obtained by oxidative pyrolysis of gasoline

Conclusions

• 1. We have studied the initiated polymerization of the alkenylaromatic fractions boiling at 120–200°C and distilled from gas pyrolysis tar or from tar obtained by oxidative pyrolysis of gasoline; the polymerization was initiated by various initiators and binary initiator mixtures.

• 2. It has been shown that at 80–120°C, 0.1–2% initiator concentration and reaction times of 40–70 h, the degree of conversion of the alkenylaromatic monomers in a 120–200°C fraction varies from 50–75 %. The polymers thus obtained are characterized by a molecular weight of 20,000–34,000 and a melting point of 130–150°C, which corresponds to a softening point of 150–170°C according to the “ring and sphere” method.

• 3. It has been found that utilization of binary initiator mixtures (tert-butyl peroxide and isopropylbenzene hydroperoxide etc.) and batch-wise addition of the initiator to the system speeds up the polymerization and favors a higher degree of conversion (95%) of the alkenylaromatic monomers in the starting material.