Effect of the crystallinity on the barrier properties of PLA based nanocomposites

J. Trifol, C. Mericer, D. Plackett, C. Sillard, M. Minelli, O. Hassager, A. E. Daugaard, J. Bras, M. Giacinti, P. Szabo

Tutkimustuotos: Artikkeli kirjassa/konferenssijulkaisussaKonferenssiesitysScientificvertaisarvioitu

Abstrakti

Nanocomposites with cellulose nanofibers and/or commercially available nanoclay (Cloisite™ 30B) were prepared and evaluated for use in food packaging. Cellulose nanofibers were extracted from sisal fibers using an optimized three-step chemical protocol. In sequence, the steps were strong alkali treatment, a bleaching process, and finally an acetylation step. Nanocomposite films were prepared by solvent casting using an optimized method for each nanofiller or nanofiller combination. The combination of nanocellulose and nanoclay within a PLA matrix decreased dramatically the oxygen barrier properties (the PLA/CNF/C30B 1% 1% showed a) 63% of decrease on the oxygen transmission rate (OTR and the PLA/CNF/C30B 5% 5% showed a 88%), water barrier properties (the PLA/CNF/C30B 1% 1% showed a 57% of decrease on the water vapour barrier properties WVTR and the PLA/CNF/C30B 5% 5% a 75%), enhanced the thermomechanical properties and crystallization kinetic (the addition of 1% CNF and 1% of C30B reduced the half crystallization time of the PLA from 25 to 5 minutes) without a significant reduction on transparency. It was found that the addition of nanofillers to the matrix was leading to reduced water diffusion than the neat PLA but the nanocomposites with CNF showed also slightly higher water absorption than neat PLA and PLA/C30B. Moreover it was also found that bigger spherulite size leads to a higher decrease on diffusivity but also to slight increase in water sorption, the smaller spherulite size was leading to a reduction in both parameters. Finally the fully crystallized PLA/C30B/CNF 1% 1% nanocomposite showed a 45% of decrease on WVTR if compared with fully crystallized PLA meaning that the presence of both nanofillers even at low load can enhance the barrier properties of PLA.

AlkuperäiskieliEnglanti
TilaJulkaistu - 2015
OKM-julkaisutyyppiEi oikeutettu
TapahtumaINTERNATIONAL CONFERENCE ON COMPOSITE MATERIALS - Copenhagen, Tanska
Kesto: 19 heinäk. 201524 heinäk. 2015
Konferenssinumero: 20

Conference

ConferenceINTERNATIONAL CONFERENCE ON COMPOSITE MATERIALS
LyhennettäICCM
Maa/AlueTanska
KaupunkiCopenhagen
Ajanjakso19/07/201524/07/2015

Sormenjälki

Sukella tutkimusaiheisiin 'Effect of the crystallinity on the barrier properties of PLA based nanocomposites'. Ne muodostavat yhdessä ainutlaatuisen sormenjäljen.

Siteeraa tätä