1 research outputs found
Highly Biodegradable and Tough Polylactic Acid–Cellulose Nanocrystal Composite
Poly(l-lactide) cellulose
nanocrystals-filled nanocomposites
were fabricated by blending of cellulose nanocrystals-<i>g</i>-rubber-<i>g</i>-poly(d-lactide) (CNC-rD-PDLA)
and commercial PLLA, in which CNC-<i>g</i>-rubber was synthesized
by ring opening polymerization (ROP) of d-lactide and a ε-caprolactone
mixture to obtain CNC-P(CL-DLA), followed by further polymerization
of d-lactide to obtain CNC-rD-PDLA. X-ray diffraction (XRD),
nuclear magnetic resonance (NMR), and solubility tests confirmed successful
grafting of the rubber segment and the PDLA segment onto CNC. Stereocomplexation
between CNC-rD-PDLA nanofillers and PLLA matrix was confirmed by FT-IR,
XRD, and differential scanning calorimetry (DSC) characterization.
The PLLA/CNC-rD-PDLA nanocomposites exhibited greatly improved tensile
toughness. With 2.5% CNC-rD-PDLA loading, strain at break of PLLA/CNC-rD-PDLA
was increased 20-fold, and the composite shows potential to replace
poly(ethylene terephthalate). SEM and small-angle X-ray scattering
(SAXS) investigations revealed that fibrillation and crazing during
deformation of PLLA/CNC-rD-PDLA nanocomposites were the major toughening
mechanisms in this system. The highly biodegradable and tough cellulose
nanocrystals-filled PLLA nanocomposites could tremendously widen the
range of industrial applications of PLA