Stereocomplex Fiber

T. Kobayashi, M. Todoki, M. Fujii, T. Takeyama and H. Tanzawa, Permeability and structure of PMMA stereocomplex hollow fiber membrane for hemodialysis, in E. Drioli and M. Nakagaki (Eds.), Proc. Eur.-fpn Cong. Membr. Membr. Processes, Plenum, New York, NY, 1986, pp. 507-513. 

Tsuji, H. and Suzuki, M. (2001) In vitro hydrolysis of blends from enantiomeric poly(lactide)s. 2. Well-stereocomplexed fiber and films. Sen i Gakkaishi, 57,198-202. 

A high voltage in electro-spinning suppressed the formation of a-crystals, and helped to form PLLA/PDLA fibers with predominately stereocomplex crystals. ... 

The stereocomplex formed from complementary strands of isotactic and syndiotactic poly(methyl methacrylate)s (it- and st-PMMAs) with an it st-stoichiometry of 1 2 represents another class of unique, polymer-hased helical supramolecules suitable for AFM studies. Although this stereocomplex has heen known for half a century, the molecular basis of the stracture and the mechanism of complex formation are still under dehate. In 1989, Schomaker and Challa proposed a double-stranded helix model for the stereocomplex based on the wide angle X-ray scattering (WAXS) analysis of the stretched fiber, which is composed of a 9i it-PMMA helix (nine repeating MMA units per turn) strrrormded hy an 18i st-PMMA helix, resulting in a double-stranded helix with a helical pitch of 1.84 nm. To verify the stmcture of the PMMA stereocomplex by the AFM technique, Kumaki et al. prepared a mixed monolayer of it- and... 

Other thermal resistance improvement technologies that have been reported include the incorporation of plant fiber [6], glass fiber [7], and inorganic filler particles [8] into the PLA matrix and the application of a stereocomplex of PLLA and PDLA [9]. 

Ikada et al. [9] found that stereocomplexation or racemic crystallization takes place between PLLA and PDLA units in chloroform solution, and obtained fibers composed of the... 

The most common strategy to decrease the price or improve the properties of polylactide to fulfill the requirements of different applications is blending. Polylactide has been blended with degradable and inert polymers, natural and synthetic polymers, plasticizers, natural fibers and inorganic fillers. The most common blends include blends with other polyesters such as polycaprolactone or PLA/starch blends. Usually the compatibility between the two components has to be improved by addition of compatibilizers such as polylactide grafted with starch or acrylic acid (114,115). Recently a lot of focus was concentrated on the development of polylactide biocomposites, nanocomposites and stereocomplex materials. In addition various approaches have been evaluated for toughening of polylactide. 

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