Nucleation Role of Basalt Fibers during Crystallization of Poly(ε-caprolactone) Composites

The crystallization behavior of the basalt fibers (BF)-filled poly(epsilon-caprolactone) (PCL) composites was studied. Both the pristine BF and the treated one have a remarkable nucleation effect on the crystallization of PCL, and the latter has a higher nucleation activity than the former. However, the PCL chain diffusion is restrained by the physical barrier effect of BF and the increased system viscosities. Yet nucleation dominates the overall kinetics because composites have far higher crystallization rates than neat PCL. The presence of BF does not alter lamellar structure, but favors the formation of the nuclei with a denser fold surface, especially in the treated BF -filled composite. The reinforcing effect of BF, together with the increased PCL crystallinity, results in increased mechanical strength of the composite system. This work can provide useful information on the structure and property control of novel PCL/BF composites.