Abstract
AbstractABCBA type pentablock copolymers, in which the A, B and C blocks are poly (p‐Dioxanone) (PPDO), poly (L‐Lactide) (PLLA), and polyethylene glycol (PEG), respectively, were synthesized via a two‐step ring‐opening polymerization in bulk using stannous octoate as the catalyst. PLA‐b‐PEG‐b‐PLA Triblock copolymer was synthesized at first and then p‐Dioxanone monomers as the other blocks were added to it. In the first step, poly ethylene glycol and, in the second step, triblock copolymer acts as the macro initiator. The obtained copolymers were identified by ⊃1&/sup;H&/I;, ⊃13&/sup;CNMR&/I; and IR&/I; spectroscopy. The intrinsic viscosity of copolymers was measured in chloroform/phenol (3/1 v/w) solution. The thermal properties, such as melting point, melting enthalpy and crystallinity, were studied. From the results of differential scanning calorimetry and thermal gravimetric analysis, it was observed that the PPDO blocks show similar crystallization behavior like homopolymer and also melting temperature of two PPDO end blocks raise with an increase in DON content in copolymer.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
