An oligomer of 2-pyrrolidone was synthesized by the reaction of potassium pyrrolidonate with carbone dioxide in benzene 35℃. The anionic polymerization of 2-pyrrolidone with oligomer of 2-pyrrolidone as an initiator and potassium hydroxide as a catalyst was attempted in order to study their catalytic effect and physical properties of the resulting polymer. When the concentration of pyrrolidone potassium salt was 9 mole percent and CO₂/K mole ratio was changed, high conversion and high inherent viscosity (3.5dl/g) were obtained.

2-pyrrolidone의 oligomer를 합성하고 이것을 개시제로 하여 음이온 중합을 시도하여 oligomer의 개시제로서의 효과와 중합체의 물리적 성질을 조사하였다. 2-pyrrolidone K-salt의 농도를 거의 9 mole%로 일정하게 하고 CO₂/K mole ratio를 변화시켜 중합시킨 결과 CO₂/K mole ratio가 0.41일때 가장 좋은 conversion과 고유 점도(3.5 dl/g)을 얻었다. 중합 반응시간이 길어도 percent conversion과 고유 점도는 CO₂/K mole ratio에 무관하여 거의 일정하였다.