Fast-Track Crystallization of PB‑1 with Sorbitol-Based Nucleating Agent

Area of Science:

• Polymer Science
• Materials Chemistry

Background:

• Polybut-1-ene (PB-1) is a polymer with unique crystallization and phase transition behaviors.
• Nucleating agents (NA) are additives used to control polymer crystallization kinetics and morphology.
• Sorbitol-based nucleating agents are commonly used in polyolefins like polypropylene.

Purpose of the Study:

• To investigate the effect of a specific sorbitol-based nucleating agent (NA) on the crystallization and phase transition of polybut-1-ene (PB-1) homopolymer and random copolymer.
• To understand how NA influences the transition from the tetragonal form II to the trigonal form I in PB-1.
• To evaluate the impact of NA solubility on PB-1 crystallization behavior.

Main Methods:

• Studying the crystallization and phase transition of PB-1 homopolymer and copolymer with and without NA.
• Observing the transformation from tetragonal form II to trigonal form I over time at room temperature.
• Analyzing changes in crystallization temperature, peak width, melting behavior, and haze.

Main Results:

• NA significantly accelerates the phase transition in PB-1, especially in the homopolymer.
• In copolymers, NA increases crystallization temperature, narrows crystallization and melting peaks, indicating a more uniform structure.
• The addition of NA leads to increased haze, confirming the formation of a two-form structure.
• NA exhibits solubility in PB-1 melt at high temperatures, influencing crystallization.

Conclusions:

• Commercial sorbitol-based NA has a substantial impact on the crystallization and phase transition of both PB-1 homopolymer and copolymer.
• NA modifies PB-1 structure, leading to improved uniformity and altered phase transition kinetics.
• Understanding NA solubility is crucial for predicting its effect on PB-1 crystallization.