Hybrid poly(lactic acid)/nanocellulose/nanoclay composites with synergistically enhanced barrier properties and improved thermomechanical resistance

Abstract

(2016). Hybrid poly(lactic acid)/nanocellulose/nanoclay composites with synergistically enhanced barrier properties and improved thermomechanical resistance. Polymer International, 65(8) Keywords:Cellulose nanofibres (CNF), nanoclay, polylactic acid (PLA), nanocomposites, barrier properties, thermomechanical properties Abstract:Poly(lactic acid) (PLA)-based hybrid nanocomposites (PLA, nanoclay and nanocellulose) were prepared by reinforcing neat PLA with commercially available nanoclay (Cloisite C30B) and nanocellulose, in the form of either partially acetylated cellulose nanofibres (CNF) or nanocrystalline cellulose (CNC).Composites with 1 or 5 wt% of nanocellulose, in combination with 1, 3 and 5 wt% of nanoclay, were prepared, and their barrier properties were investigated. It was found that the combination of clay and nanocellulose clearly results in synergistic behaviour in terms of the oxygen transmission rate (OTR) through a reduction of up to 90% in OTR and a further reduction in the water vapour transmission rate (WVTR) of up to 76%. In addition, the nanocomposite films showed improved thermomechanical resistance and improved crystallisation kinetics while maintaining high film transparency. This makes hybrid PLA/CNF/C30B nanocomposites a very promising material for food packaging applications.

Structure-properties relationships in melt reprocessed PLA/hydrotalcites nanocomposites

“…For this purpose, the study of thermo-mechanical degradative phenomena associated to its re-processing [20,22,23] is of great concern in order to assess the possibility of recycling PLA-based nanocomposites. To enhance some properties of PLA, such as mechanical and gas barrier properties and to extend its use in food packaging applications, small amounts of nanoparticles can be loaded in the matrix [24]. For this purpose, in this work, we used hydrotalcites (HT) as nanofiller.…”

Nanocellulose as a green and sustainable emerging material in energy applications: a review

“…Numerous studies have been dedicated to the hydrophobic surface of nanocellulose to improve the compatibility between nanocellulose and hydrophobic characteristics of polylactic acid . For example, nanocellulose has been hydrophobized using dodecanoic acid in an esterification reaction, resulting in more interaction, good distribution, and good wettability with polylactic acid . The series of improvement in reinforcing properties of polylactic acid by NCC could be explained by the good dispersion of NCC in the polylactic acid matrix.…”

“…[68] For example, nanocellulose has been hydrophobized using dodecanoic acid in an esterification reaction, resulting in more interaction, good distribution, and good wettability with polylactic acid. [69] The series of improvement in reinforcing properties of polylactic acid by NCC could be explained by the good dispersion of NCC in the polylactic acid matrix. The good dispersion of NCC within the polylactic acid matrix provides a strong, tough, and more optically transparent composite material.…”

Nanocellulose reinforced as green agent in polymer matrix composites applications

“…The biodegradable properties of green polymeric composites imply the degradation of a polymer in natural environment that includes changes to the chemical structure, the loss of mechanical and structural properties, and conversion into other compounds that are beneficial to the environment . Green polymeric composites have been used effectively in many applications, including mass produced consumer products with short life cycles or products intended for one use or short period prior to disposal . Indeed, it could also be used for indoor applications and remain in use for several years.…”

“…For green polymeric composites design, the modification of the cellulose as reinforcement agent and polymer matrices is regarded as an important step in improving the interfacial adhesion between the different components. This would consequently enhance the macroscopic properties, such as the mechanical, barrier, and resistance properties . Generally, surface modification is usually performed by chemical treatment such as dewaxing, alkali treatment, graft copolymerization, silane treatment, etherification, acetylation, peroxide treatment, and isocyanates grafting …”