Exfoliated clay nanocomposites of renewable long-chain aliphatic polyamide through in-situ polymerization

摘要

The current study was performed to synthesize a series of renewable polyamide 614/organoclay nanocomposites (PAC) with the improved structural, mechanical, and thermal properties via in-situ polymerization. The uniform dispersion and exfoliation of clay into the PA614 matrix, particularly at a lower loading of organoclay (less than 3%), confirmed via structural analyses (XRD, SEM, and TEM). Furthermore, the mechanical tests revealed remarkable improvement; namely, the tensile strength and storage modulus increased by 27% and 30%, respectively, in the sample contained 2% organoclay. Similarly, the TGA results showed a slight improvement in the thermal stability of the nanocomposite samples. Altogether, these improvements confirmed excellent compatibility between nanofiller and matrix and the organoclay homogenous dispersion into the PA matrix achieved by employing in-situ polymerization. Furthermore, all the samples illustrated a shear-thinning behavior over frequency attributed to the lack of time for the polymer chain to respond to the applied oscillation. Finally, the crystallinity of the samples diminished upon increasing the filler's content, which could be due to the decrease of free volume resulting from the presence of organoclay. To sum up, the current investigation supported the benefit of employing in-situ polymerization to synthesize renewable PA614/clay nanocomposites with enhanced physio-mechanical properties, which could be appropriate candidates for engineering applications.