Melt‐Intercalated Starch Acetate Nanocomposite Foams as Affected by Type of Organoclay

Abstract

Starch acetate nanocomposite foams with four organoclays (Cloisite 30B, 10A, 25A, and 20A) were prepared by melt‐intercalation methods. The structural properties, thermal behaviors, and mechanical properties were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetry analyses (TGA), and Instron universal testing machine. XRD results indicated that the intercalation of starch acetate into the nanoclay layers occurred for all four clays. The extent of intercalation depended on the type of organoclay and was exhibited in the sequence of Cloisite 30B >10A >25A >20A. SEM results indicated a decrease in cell size in the starch acetate foam matrix with the addition of nanoclay. Glass transition temperature (Tg) and onset temperatures of thermal degradation increased with the addition of organoclay into the starch acetate matrix. The incorporation of organoclays decreased significantly the compressibilities of starch acetate nanocomposites and did not substantially affect their spring indices.

Advanced Nano-biocomposites Based on Starch

“…-Oxygen barrier property: a higher oxygen barrier can be ascribed to the silicate layers inducing a higher tortuosity and longer diffusion pathways for oxygen molecules (Lilichenko et al 2008;Maksimov et al 2009;Zeppa et al 2009). -Thermal stability: improvement in the thermal stability can be due to several concomitant phenomena such as (a) the higher thermal stability of the inorganic phase (phyllosilicate) compared to the organic one (starch), (b) the phyllosilicate acting as a heat barrier which enhances the overall stability (Cyras et al 2008;Ibrahim 2011), (c) the increase in the tortuosity of the diffusion pathways for oxygen and the combustion (pyrolysis) gas (Alexandre and Dubois 2000;Chiou et al 2007;Chivrac et al 2010d;Cyras et al 2008;Namazi et al 2009;Xu et al 2005), and (d) the reorganization of the starch structure with less exposed hydroxyl groups and thus less susceptibility to degradation (Pandey and Singh 2005;Wang et al 2010b;Wilhelm et al 2003b). …”

“…To seek better performance, various chemically modified starches have also been experimented to develop nano-biocomposites Hassan Nejad et al 2011;Kvien et al 2007;Namazi et al 2009;Nejad et al 2010;Qiao et al 2005;Wilhelm et al 2003a;Xu et al 2005). Chemical modification can result in starch derivatives with varied properties such as the molecular chain length and hydrophilicity, which could affect the interactions with a phyllosilicate.…”

“…Furthermore, showed that this kind of materials could also be useful in the removal of a dye (safranine T) from an aqueous solution. Xu et al (2005) prepared starch acetate-based nano-biocomposite foams reinforced by different OMMTs by melt extrusion and found the nano-biocomposite foams showed a decrease in the cell size. The incorporation of OMMT also significantly decreased the compressibility of the nanobiocomposite foams but did not substantially affect their spring index (Xu et al 2005).…”

Nanocomposites of crosslinked starch phthalate and silane modified nanoclay: Study of mechanical, thermal, morphological, and biodegradable characteristics

“…Esterification is one of the methods to derivatize and replace the hydroxyl groups of starch, as esters behave as internal plasticizers [10]. Thus, starch acetate has been compounded with nanoclay and characterized by varying the type of organoclay [11]. Composites of mixed starch esters have been developed and reinforced with montmorillonite [12,13].…”

High Mechanical Properties of Polychloroprene/Montmorillonite Nanocomposites

“…Especially, researches on the subject of rubber nanocomposite have been attracted much interest. [10][11][12] Polychloroprene or chloroprene rubber, introduced by DuPont in 1931, was the first synthetic rubber developed that exhibited the elastomeric properties of natural rubber. It remains one of the most important speciality elastomers with an annual consumption of 300,000 tons worldwide.…”