Effect of Phenolic Compounds and Resin Acids on the Polymerization of Styrene in the Coexistence of Inhibitors

Abstract

禁止物質共存下のスチレン重合における, フェノール性化合物と樹脂酸の影響を, ディラトメーターを使用して検討し, 次の結果を得た。1. ヒドロキノン存在下では, ケルセチンとプロトカテク酸エチルが, 重合遅延の相乗効果を示した。2. ヒドロキノンとピロカテコール存在下では, フェノール性化合物の添加により禁止時間は, 余り増加しない。3. ヒドロキノンとピロカテコール存在下では, 特に樹脂酸のビペリジン塩フラクションが, 禁止時間を短縮する拮抗作用を示し共役二重結合を持つアビエチン酸が原因であろう。4. 非共役樹脂酸であるクリプトピマール酸は, ヒドロキノンの重合遅延に対し, 相乗作用を示した。

The purpose of this paper is to investigate the synergistic and competitive effects of phenolic compounds and resin acids on the polymerization of styrene in the coexistence of inhibitors, and the results obtained are as follows: 1. Quercetin or ethyl protocatechuate exhibits a synergistic effect of retardation on the polymerization in the presence of hydroquinone. 2. In the presence of hydroquinone or pyrocatechol the induction period does not increase significantly with the addition of phenolic compounds. 3. In the presence of hydroquinone or pyrocatechol total resin acids, specially piperidine salt fraction, exhibit the competitive effect which reduces the induction period. It is considered that abietic acid which has the conjugated double bond takes part in the effect. 4. Cryptopimaric acid which has not the conjugated double bond retards the polymerization remarkably in the presence of hydroquinone.