The structure of crystallisable copolymers of l-lactide, ε-caprolactone and glycolide

• Main Authors: Channuan W., Siripitayananon J., Molloy R., Sriyai M., Davis F.J., Mitchell G.R.
• Format: Article
• Language: English
• Published: 2014
• Online Access: http://www.scopus.com/inward/record.url?eid=2-s2.0-33748921879&partnerID=40&md5=d1e685ed602336dd76f859ebd9f63375; http://cmuir.cmu.ac.th/handle/6653943832/4964
• Institution: Chiang Mai University

We apply a new X-ray scattering approach to the study of melt-spun filaments of tri-block and random terpolymers prepared from lactide, caprolactone and glycolide. Both terpolymers contain random sequences, in both cases the overall fraction of lactide units is ∼0.7 and 13C and 1H NMR shows the lactide sequence length to be ∼9-10. A novel representation of the X-ray fibre pattern as series of spherical harmonic functions considerably facilitates the comparison of the scattering from the minority crystalline phase with hot drawn fibres prepared from the poly(l-lactide) homopolymer. Although the fibres exhibit rather disordered structures we show that the crystal structure is equivalent to that displayed by poly(l-lactide) for both the block and random terpolymers. There are variations in the development of a two-phase structure which reflect the differences in the chain architectures. There is evidence that the random terpolymer includes non-lactide units in to the crystal interfaces to achieve a well defined two-phase structure. © 2005 Published by Elsevier Ltd.