Effect of Chitin Nanocrystals on Crystallization and Properties of Poly(lactic acid)-Based Nanocomposites [Elektronisk resurs]

• The crystalline phase of poly(lactic acid) (PLA) has crucial eects on its own propertiesand nanocomposites. In this study, the isothermal crystallization of PLA, triethyl citrate-plasticizedPLA (PLA–TEC), and its nanocomposite with chitin nanocrystals (PLA–TEC–ChNC) at dierenttemperatures and times was investigated, and the resulting properties of the materials werecharacterized. Both PLA and PLA–TEC showed extremely low crystallinity at isothermal temperaturesof 135, 130, 125 ºC and times of 5 or 15 min. In contrast, the addition of 1 wt % of ChNCs significantlyimproved the crystallinity of PLA under the same conditions owing to the nucleation eect ofthe ChNCs. The samples were also crystallized at 110 ºC to reach their maximal crystallinity,and PLA–TEC–ChNC achieved 48% crystallinity within 5 min, while PLA and PLA–TEC required 40 min to reach a similar level. Moreover, X-ray diffraction analysis showed that the addition ofChNCs resulted in smaller crystallite sizes, which further influenced the barrier properties and hydrolytic degradation of the PLA. The nanocomposites had considerably lower barrier propertiesand underwent faster degradation compared to PLA–TEC110. These results confirm that the additionof ChNCs in PLA leads to promising properties for packaging applications. 

Ämnesord

Engineering and Technology  (hsv)

Industrial Biotechnology  (hsv)

Bio Materials  (hsv)

Teknik och teknologier  (hsv)

Industriell bioteknik  (hsv)

Biomaterial  (hsv)

Trä och bionanokompositer  (ltu)

Wood and Bionanocomposites  (ltu)

Genre

government publication  (marcgt)

Indexterm och SAB-rubrik

poly(lactic acid)

chitin nanocrystals

nanocomposites

liquid-assisted extrusion

crystallinity

barrier properties

hydrolytic degradation