The present study discusses structural aspects of nanocomposites and the ability of layered nanosilicates to alter the flow behaviour of poly(lactic acid) (PLA) melts. In addition, dynamic and static mechanical properties of PLA nanocomposites prepared from melt mixing method have been also discussed. A comparative study of nanocomposite properties has been conducted using two different nanoclays, natural montmorillonite modified with alkyl ammonium surfactant (OMMT), and commercially available organosilicate, Cloisite 30B, as reinforcements within the PLA matrix. Since OMMT has undergone better intercalation within the matrix, the corresponding nanocomposite showed superior mechanical and rheological characteristics than its C30B counterpart. 1. Introduction Environmental impact generated by accumulating petroleum based plastic wastes is one of the most pondering topics among the researchers and environmentalists today. In this view, renewable resource based completely biodegradable aliphatic polyesters like poly(lactic acid) (PLA) and poly(hydroxyalkanoates) (PHA), carbohydrate based materials like starch and cellulose are under the scrutiny as apt replacement for petroleum based plastics. But still processability and cost are major drawbacks of these materials to clinch their niche in the market for various specific applications including “disposable materials.” Researchers like Ray et al. reported about the improvements in processability and performance characteristics of PLA by reinforcing it with layered nanosilicates [1]. Also, nanocomposites of PHAs, starch, and petroleum based biodegradable materials like poly(butylene adipate-co-terephthalate) (PBAT) and poly(caprolactone) (PCL) with improved processability; mechanical and thermal characteristics also have been reported by various researchers. Among all, PLA is highly crystalline in nature with inherent biodegradability as well as enough life to maintain mechanical properties without rapid hydrolysis. As per the literature, mechanical and thermal properties of PLA show considerable improvement as a function of extent of intercalation/exfoliation of nanoclay layers within the matrix [2–5]. However, the relationship between structural features and rheological characteristics of PLA melts in its nanocomposites still demands detailed analysis through fundamental point of view to better understand the materials processability under a given set of parameters. In this view, the current study discusses the structural aspects of nanocomposites and the ability of layered nanosilicates to alter the flow
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