Effects of branches on the isothermal crystallization of copolymers based on poly(-caprolactone)

NINAGO, MARIO; REDONDO, FRANCO LEONARDO; DE FREITAS, AUGUSTO G. O.; GIACOMELLI, CRISTIANO; CIOLINO, ANDRÉS E.; VILLAR, MARCELO A.

MACROMOLECULAR SYMPOSIA

WILEY

Lugar: New York; Año: 2019 vol. 383 p. 1700082 - 1700082

1022-1360

A linear poly(-caprolactone), PCL, and grafted copolymers based on poly(2-hydroxyethylmethacrylate) and poly(-caprolactone) were used to study the effect of branches on PCL crystallization process. Copolymers were synthetized by a combination of ring opening polymerization and reversible addition fragmentation chain transfer polymerization, showing molar masses between 32,000 and 46,000 g mol-1 with Mw/Mn lower than 1.19. Isothermal crystallization kinetic was performed by Differential Scanning Calorimetry combining Avrami and Hoffman-Weeks theories. Regarding to Avrami parameters, copolymers exhibited half-life crystallization times 42 times higher than PCL homopolymer and two-dimensional crystallization growth. Copolymers? growing rate values were 51 times higher than PCL values according to Hoffman-Weeks equation. These results suggest that the interaction of grafted chains could hinder the rearrangement of PCL by reducing their final crystallization capacity.