Isothermal and non-isothermal crystallization of isotactic polypropylene nucleated with 1,3,5-benzenetricarboxylic acid tris(cyclohexylamide)

• 1,3,5-Benzenetricarboxylic acid tris(cyclohexylamide) was a highly effective nucleating agent for iPP.
• Addition of 1,3,5-benzenetricarboxylic acid tris(cyclohexylamide) could shorten half crystallization time (t1/2) and greatly increased the crystallization rate of iPP.
• Addition of 1,3,5-benzenetricarboxylic acid tris(cyclohexylamide) could decrease the crystallization activation energy of iPP.

Isothermal and non-isothermal crystallization kinetics of isotactic polypropylene (iPP) nucleated with 1,3,5-benzenetricarboxylic acid tris(cyclohexylamide) (BTCA-TCHA) were investigated by differential scanning calorimetry (DSC). The classical Avarmi equation and the Mo method were used to analyze the experimental data. The results showed the Avrami equation and the Mo method described the isothermal and non-isothermal crystallization processes of iPP accurately, respectively. During isothermal crystallization, addition of BTCA-TCHA shortened half crystallization time (t1/2) and increased crystallization rate of iPP greatly. In addition, addition of BTCA-TCHA decreased the crystallization activation energy ΔE from 370 kJ/mol of virgin iPP to 312 kJ/mol. During non-isothermal crystallization, half time of the crystallization (t1/2) of virgin iPP was larger than that of nucleated iPP under the same cooling rate and the required cooling rate of virgin iPP to reach the same relative crystallinity was higher than that of nucleated iPP, indicating that addition of BTCA-TCHA increased the crystallization rate obviously.