Premium
A comparative study of poly( l ‐lactide)‐ block ‐poly( ϵ ‐caprolactone) six‐armed star diblock copolymers and polylactide/poly( ϵ ‐caprolactone) blends
Author(s) -
Konwar Debanga Bhusan,
Jacob Josemon,
Satapathy Bhabani K
Publication year - 2016
Publication title -
polymer international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.592
H-Index - 105
eISSN - 1097-0126
pISSN - 0959-8103
DOI - 10.1002/pi.5168
Subject(s) - materials science , copolymer , caprolactone , crystallinity , polymer chemistry , dynamic mechanical analysis , polymer , lactide , polymerization , melting point , polymer blend , miscibility , crystallite , composite material , chemical engineering , engineering , metallurgy
This paper deals with the synthesis of a series of six‐armed star diblock copolymers based on poly( l ‐lactide) ( PLLA ) and poly( ϵ ‐caprolactone) ( PCL ) by ring‐opening polymerization using stannous octoate as catalyst and the preparation of polylactide ( PLA )/ PCL linear blends using a solution blending technique, while keeping the PLA ‐to‐ PCL ratio comparable in both systems. The thermal, rheological and mechanical properties of the copolymers and the blends were comparatively studied. The melting point and the degree of crystallinity were found to be lower for the copolymers than the blends due to poor folding property of star copolymers. Dynamic rheology revealed that the star polymers have lower elastic modulus, storage modulus and viscosity as compared to the corresponding blends with similar composition. The blends show two‐phase dispersed morphology whereas the copolymers exhibited microphase separated morphology with elongated (worm‐like) microdomains. The crystalline structures of the copolymers were characterized by larger crystallites than their blend counterparts, as estimated using Sherrer's equation based on wide‐angle X‐ray diffraction data. © 2016 Society of Chemical Industry