Akademik Veri Yönetim Sistemi
9th Polymer Science and Technology Congress (PolymerTR), Ankara, Türkiye, 16 - 18 Eylül 2024, ss.17
In-situ self-reinforced PLA based structures were prepared by introduction of crystallites of a
semicrystalline polylactide (cPLA) in an amorphous PLA (aPLA) and its blends with poly (butylene
adipate-co-terephthalate) (PBAT). To ensure self-reinforcing, cPLA as a minor phase was blended with
aPLA and aPLA/PBAT at processing temperatures below the crystal melting peak of cPLA. Blending
process was first applied via injection molding (IM) to produce self-reinforced PLA (SR-PLA) at
various ratios of 100/0, 95/5, 90/10, 85/15, and 80/20 (wt/wt). Temperatures in the IM barrel and mold
had significant effects on maintaining the cPLA crystallites, which improved the mechanical properties
of SR-PLA. Then, PBAT was melt-blended with SR-PLA samples at different aPLA/cPLA weight
ratios of 100/0, 90/10, 80/20, and 70/30 (wt/wt) to create SR-PLA/PBAT at a specified ratio of 85/15
(wt/wt). These mixtures were first produced in an internal melt mixer (MM) to assess their rheological
characteristics. cPLA reinforcing efficiency was confirmed through the rheological analysis both in
aPLA and aPLA/PBAT. In order to investigate the mechanical and thermal properties of the SRPLA/PBAT
blends,
similar
blends
were
also
produced
through
IM
method.
The
notable
impact
of
cPLA
ratios
in
blends
resulted
in
remarkable
increases
in
toughness
and
strain
at
break
values.
This
resulted
from
the expanded crystallite network within the matrix, which further refined the PBAT droplets.
Morphological observations of the blends processed using MM and IM revealed further refinement of
PBAT droplets in the IM process. The cPLA crystallites could have been further stretched toward a
fiber-like structure as a result of the generated shear during molding, which could also have increased
matrix viscosity and refined PBAT droplets.