화학공학소재연구정보센터
Molecular Crystals and Liquid Crystals, Vol.445, 57-63, 2006
Stereocomplexation effects induced by mixtures of enantiomeric polylactides on hydrolytic behaviors and surface structure
The effects of stereocomplexation of enantiomeric polylactide ( PLA) mixture films, ( l-PLA/d-PLA), on hydrolytic behaviors and surface structure were investigated by Langmuir technique and X-ray photoelectron spectroscopy, respectively. The alkaline hydrolysis rate of stereocomplexed monolayers from equimolar l-PLA and d-PLA was much slower than those of their homopolymers. The ( l-PLA-b-PDMS-b-l-PLA/l-PLA, 50/50 by wt.%) mixture film showed the surface segregation of PDMS at the surface layer while the surface composition of PDMS in ( l-PLA-bPDMS-b-l-PLA/d-PLA, 50/50 by wt.%) was similar to its bulk composition. These are likely due to strong interaction between d- and l-lactide unit sequences, which prevents the penetration of water into the bulk and surface segregation of PDMS.