Influence of blending and blend morphology on the thermal properties and crystallization behaviour of PLA and PCL in PLA/PCL blends

• Published in: Journal of materials science Vol. 51; no. 9; pp. 4670 - 4681
• Main Authors: Luyt, A. S., Gasmi, S.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-05-2016; Springer; Springer Nature B.V
• Subjects: Analysis; Annealing; Behavior; Blending; Blends; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Cold crystallization; Crystallization; Crystallography and Scattering Methods; Crystals; Materials Science; Mixtures; Morphology; Nucleation; Original Paper; Polymer Sciences; Size distribution; Solid Mechanics; Spherulites; Thermal properties; Thermodynamic properties; Two-dimensional analysis; Differential Scanning Calorimeter; PHBV; Differential Scanning Calorimeter Curve; Cold Crystallization Temperature; Cold Crystallization
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-016-9784-z

In this paper, we reported on the influence of PCL on the cold crystallization behaviour of PLA in different PLA/PCL blends, and on the influence of blending with PLA on the PCL crystallization behaviour and kinetics. The presence of PCL in the blends had a strong influence on PLA cold crystallization, and the extent of this influence was determined by the blend morphology. Successive self-nucleation and annealing (SSA) analysis of PCL crystallization in the blends showed that the presence and amount of PLA in the blends had a strong influence on the crystal size distribution in the main crystalline fraction of PCL. A kinetic analysis of the crystallization of neat PCL and PCL in the blends showed that the crystallization mechanism of the neat PCL changed from instantaneous/heterogeneous nucleation and two-dimensional growth to sporadic/homogeneous nucleation and two-dimensional growth with decreasing crystallization temperature, while for PCL in the blends, the mechanism over the whole crystallization temperature range was that of instantaneous/heterogeneous nucleation and three-dimensional growth into spherulites. PCL in the blends also crystallized significantly faster than neat PCL, but there was little difference between the crystallization rates of PCL in the different blends.