Control of properties of PLA-PFPE-PLA triblock copolymers using stereocomplex between l-LA and d-LA sequences

• Published in: Molecular Crystals and Liquid Crystals 2016-09, Vol.636 (1), p.128-133
• Main Authors: Lee, Hak Yong, Kim, Yeong Woo, Park, Chan Young, Lee, Chang-Han, Kim, Seong-Soo, Lee, Won-Ki
• Format: Article
• Language: English
• Subjects: Biodegradability; Biodegradation; Blends; Block copolymers; Chemical synthesis; Copolymerization; Copolymers; Formations; perfluoro polyether; poly(d-lactide); poly(l-lactide); stereocomplex; Stereocomplexes; Surface properties; Synthesis (chemistry)
• ISSN: 1542-1406; 1563-5287; 1527-1943
• DOI: 10.1080/15421406.2016.1201394

Two type of triblock copolymers [poly(l-lactide)-b-perfluoro polyether-b-poly(l-lactide) (fluoro l-PLA) and poly(d-lactide)-b-perfluoro polyether-b-poly(d-lactide) (fluoro d-PLA)] (fluoro PLAs) were synthesized by ring-opening polymerization. The synthesized triblock copolymers showed more hydrophobic properties than pristine l-PLA due to the perfluoro polyether (PFPE). To control the surface properties, the blends were prepared by mixing fluoro PLAs with l-PLA. The degradation rates of the fluoro PLAs/l-PLA blends were retarded due to the surface segregation of PFPE which has lower surface energy. In case of the fluoro d-PLA/l-PLA blends, however, the stereocomplex formation between the l-lactide and d-lactide sequences enhanced the thermal and enzymatic stabilities of l-PLA. As a result, the biodegradability of l-PLA can be controlled by copolymerization or the formation of a stereocomplex.