Abstract

Thermoplastic poly(ester−urethanes) were polymerized in a two-step process: a condensation copolymerization of lactic acid (LA) and e-caprolactone (CL), using stannous octoate as catalyst, followed by an increase in the molecular weight through urethane linking. The use of 1,4-butanediol results in oligomer molecules with hydroxyl functionality at both ends. The effect of comonomer ratio on the thermal and mechanical properties of the poly(ester−urethane) was investigated. SEC, FTIR, and 13C NMR were used to confirm the formation and structure of the polymer; a random sequence distribution of the comonomer units was concluded along the polymeric chains. All poly(ester−urethanes) were amorphous, with Tg varying from 53 to −45 °C. Poly(ester−urethanes) with a small amount of CL units were rigid, having a tensile modulus of 1700−2100 MPa, maximum stress of 36−47 MPa, and maximum strain of 4−7%. CL-rich poly(ester−urethanes) were highly elastomeric with maximum stress of 9 MPa and with maximum strain over 10...

Full Text
Paper version not known

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 call

Disclaimer: 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.