尼龙612的等温结晶动力学

The Isothermal Melt Crystallization Kinetics of Nylon 612

用差示扫描量热（DSC）研究了尼龙612的等温结晶动力学。实验结果表明,在所研究的等温结晶温度范围内（184℃、186℃、188℃、190℃、192℃）,尼龙612达到最大结晶速率时的时间、半结晶期和动力学结晶速率常数分别为：0.12min、0.19 min、0.22 min、0.29 min、0.59 min;0.15 min、0.22 min、0.24 min、0.33 min、0.64 min和22.03 min-1、23.28min-1、8.85 min-1、5.15 min-1、1.93 min-1。等温结晶过程符合Avrmi方程,二次结晶现象不明显。在等温结晶过程中得到的Avrmi指数n在1.81~2.32之间,由理论分析可知,尼龙612等温结晶是一维生长和二维盘状生长。由Arrhe-nius方程求得尼龙612的等温结晶活化能ΔE=-209.5 kJ/mol。

The isothermal melt crystallization kinetics of nylon 612 was systematically studied using differential scanning calorimetry（DSC）.In the studied temperature range of isothermal crystallization（184 ℃ 186 ℃,188 ℃,190 ℃,192 ℃）,crystallization rate of nylon 612 reaches the maximum when the time for half-crystallization temperature and crystallization kinetic rate constants are 0.12 min, 0.19 min,0.22 min,0.29 min,0.59 min;0.15 min,0.22 min,0.24 min,0.33 min,0.64 min and 22.03 min-1,23.28 min-1,8.85 min-1,5.15 min-1,1.93 min-1 respectively.Isothermal crystallization process is in line with Avrami equation,the phenomenon of secondary crystallization is not obvious.The Avrami exponent is determined for nylon 612 as 1.81～2.32 approximately which implies that the isothermal crystallization is one or two-dimensional growth.The calculated activation energy is-209.5 kJ/mol for isothermal crystallization by Arrhenius equation.