Journal
BIOMACROMOLECULES
Volume 6, Issue 3, Pages 1789-1796Publisher
AMER CHEMICAL SOC
DOI: 10.1021/bm050098f
Keywords
-
Ask authors/readers for more resources
Poly(lactic acid), PLA, was blended with monomeric and oligomeric plasticizers in order to enhance its flexibility and thereby overcome its inherent problem of brittleness. Differential scanning calorimetry, dynamic mechanical analysis, transmission electron microscopy, and tensile testing were used to investigate the properties of the blends. Monomeric plasticizers, such as tributyl citrate, TbC, and diethyl bishydroxymethyl malonate, DBM, drastically decreased the T-g of PLA, but the blends showed no morphological stability over time since rapid cold crystallization caused a size reduction of the amorphous domains in PLA. Consequently, the ability of PLA to accommodate the plasticizer diminished with the increase in crystallinity and migration of the plasticizer occurred. Increasing the molecular weight of the plasticizers by synthesizing oligoesters and oligoesteram ides resulted in blends that displayed T-g depressions slightly smaller than with the monomeric plasticizers. The compatibility with PLA was dependent on the molecular weight of the oligomers and on the presence or not of polar amide groups that were able to positively interact with the PLA chains. Aging the materials at ambient temperature revealed that the enhanced flexibility as well as the morphological stability of the films plasticized with the oligomers could be maintained as a result of the higher molecular weight and the polar interactions with PLA.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available