In this study,we compared the effect of n-pentane and ice-water bath on removing the thermal effect in the poly(p-phenylene terephthalamide)(PPTA) polymerization process.The results indicate that the n-pentane can help to transfer the reaction heat faster and better.Adding suitable amount of n-pentanes into the PPTA preparation process not only improve the heat transfer,but also reduce the motor power in the polymerization process.Moreover,the introduction of n-pentane properly does not result in decrease of the inherent viscosity(η_(inh)) of polymer.Instead,it leads to increased viscosity of polymer during the PPTA preparation process.The results indicate that n-pentane can effectively transfer the reaction heat and avoid overheating during the polymerization of PPTA. In this study, we compared the effect of n-pentane and ice-water bath on removing the thermal effect in the poly (p-phenylene terephthalamide) (PPTA) polymerization process. The results indicate that the n-pentane can help to transfer the reaction heat faster and better. Adding suitable amount of n-pentanes into the PPTA preparation process not only improve the heat transfer, but also reduce the motor power in the polymerization process. More over, the introduction of n-pentane properly does not result in decrease of the inherent viscosity (η_ (inh)) of polymer. Instead, it leads to increased viscosity of polymer during the PPTA preparation process. The results indicate that n-pentane can effectively transfer the reaction heat and avoid overheating during the polymerization of PPTA.