The equation of polymerization rate of L-alanine NCA initiated by n-butylamine in acetonitrile was determined by measuring the CO₂ evolved in the reaction. Though the reaction was heterogeneous as acetonitrile was nonsolvent for poly-L-alanine, the rate of polymerization could be represented as second order rate equation which was first order with respect to monomer and initiator concentrations, respectively. The polymerization rate of L-alanine NCA proceeded fast in early step from initiation until about 70 minutes but slow in the next step, and in each step, the reaction rate constants were obtained at temperature range from 0℃ to 35℃. The activation energies in fast and slow rate step were 3.7 kcal/mole and 4.1 kcal/mole, respectively.

Acetonitrile중에서 n-butylamine에 의해 개시되는 L-alanine NCA의 중합반응속도를 반응중 발생하는 CO₂량을 측정함으로서 구하였다. Acetonitrile이 polypeptide의 용매가 아니어서 불균일반응계이지만 중합속도는 모노머와 개시제의 농도에 각각 1차로 표시되었다. 이 반응은 속도가 빠른 단계와 속도가 느린 단계인 이단계반응속도곡선을 나타냈으며 각 경우의 속도정수를 0~35℃에서 구하였다. 또한 속도가 빠른 단계에서의 활성화에너지는 3.7kcal/mole이었고 속도가 느린 단계에서의 활성화에너지는 4.1kcal/mole이었다.

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