Crystallization and thermal properties of polylactide/palygorskite composites

Abstract

Polylactide palygorskite (fibrous clay) composites were prepared by solvent casting method. Both pristine and organically modified palygorskite were used for composite preparation. The detailed crystallization behavior, morphology, and thermal properties of neat polylactide and the corresponding composites were investigated by using differential scanning calorimetry, polarized optical microscopy, scanning electron microscopy and wide angle X‐ray diffraction techniques. The results showed that the crystallization and thermal characteristics of neat PLA were influenced significantly by the presence of palygorskite nanoparticles. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40414.

An overview of the recent advances in polylactide‐based sustainable nanocomposites

“…Pillai et al [ 51 ] prepared PLA/Paly nanocomposites by solvent casting in chloroform. Both pristine and organically modified palygorskite (Org‐paly) (prepared by cation exchange reaction between Paly with a quaternary ammonium salt di (hydrogenated tallow) dimethyl ammonium chloride) were used for nanocomposite preparation.…”

“…Among the nanofillers, nanoclays are the oldest and have attracted maximum interest among researchers [41] because of the significant enhancement in mechanical, barrier, and flame resistance properties, as well as accelerated biodegradation, which they help to achieve. [10,13] Though organically modified layered silicates (OMLS) are the most widely used clays, [3,[42][43][44][45][46] use of other clays with different morphologies, such as halloysite nanotubes (Hal or HNT), [24,47,48] sepiolite (a fibrous silicate having microporous channels running along the length of the fibers), [49,50] and palygorskite (Paly) (a fibrous silicate having needle like morphology) [51] has also been reported in literature. Due to its recyclability, anisotropic shape, biocompatibility, adjustable surface chemistry and the ability to impart superior, thermal, mechanical, and barrier properties, nanocellulose is another filler, which has gained significant interest in research on PLA-based nanocomposite.…”

“…PLA/OMMT nanocomposites with well-dispersed clay have been prepared by solvent casting method and characterized by several research groups. [109][110][111][112][113] Pillai et al [51] prepared PLA/Paly nanocomposites by solvent casting in chloroform. Both pristine and organically modified palygorskite (Org-paly) (prepared by cation exchange reaction between Paly with a quaternary ammonium salt di (hydrogenated tallow) dimethyl ammonium chloride) were used for nanocomposite preparation.…”

“…Reproduced with permission. [51] Copyright 2014, Wiley periodicals, Inc 12 for the nanocomposites containing 0.2 and 0 wt% o-PCL, respectively, both compositions containing 5 wt% OMMT. In addition to o-PCL, the use of various other polymers as compatibilizers and plasticizers, in the preparation of PLA/C18-MMT nanocomposites by melt blending, has been reported in the literature.…”

Evaluation of crystallinity and gas barrier properties of films obtained from PLA nanocomposites synthesized via “in situ” polymerization of l-lactide with silane-modified nanosilica and montmorillonite

“…This process is diffusion-controlled and requires long residence times under the pressure buildup, occurring inside the extruder; the drawback is that high residence times or high screw speeds may lead to polymer degradation, especially with polymers having low thermal stability, such as PLA [13,14]. Moreover, it has been found that clay exfoliation may not be a sufficient condition to obtain optimum properties; clay platelets dispersion and polymer-clay interaction need to be also taken into consideration to produce high performance nanocomposites [15][16][17]. Also nanosilica has been largely used to improve the properties of polymers such as PLA, to control rheological behavior or as a structural reinforcement [18][19][20]; as reported for clay particles, also with nanosilica it is important to obtain a very good dispersion of the mineral in the polymer matrix.…”