Figure 6 - TGA/DTG curves of clays: (a, b) natural and organo Bofe clay and (c, d) Chocolate clay, respectively. 3.2.2 PLA biocomposites Biocomposite thermal properties showed no significant changes with preparation method, indicating stability at normal storage temperatures. Thermal decomposition occurred in three stages, similar to natural bentonites. Casting films and extrusion sheets exhibited comparable degradation rates, suggesting processing methods don't impact thermal stability. 3.3 Differential scanning calorimetry - DSC DSC data (Figure 7a) shows neat PLA with a Tg of ~54°C, Tc of ~103°C, Tm of ~175°C, and Xc of ~12%, consistent with PLA cast films [Lima ET AL., 2019]. The addition of organoclay shifted PLA transition temperatures (Tg, Tc, Tm) to higher values and increased crystallinity, suggesting that montmorillonite layers act as nucleation sites for PLA crystallization [Chang ET AL., 2016]. The affinity of PLA for silicate and organosilicate layers shifted the melting temperature to higher values [Rabelo ET AL., 2022], indicating that the clay influences the crystalline structure of PLA. However, the PLA/Organo Bofe sample exhibited divergent DSC and XRD results, suggesting that Organo Bofe clay reduced PLA crystallinity. This may be due to altered PLA chain packing, disrupting crystallization via physical interactions [Crawford and Mekonnen, 2025]. In contrast, Organo Chocolate clay enhanced PLA crystallinity, as confirmed by XRD and DSC analyses. The increased melting and crystallization temperatures suggest that the clay's nucleation effect promoted the formation of highly organized PLA crystals [Gao and Masato, 2024]. Organo Bofe clay decreased Tg and Tm, suggesting poor nucleation, while Organo Chocolate clay maintained Tg and promoted PLA crystallization, indicating a nucleation effect [Gorrai ET AL., 2013]. Extruded PLA/organoclay samples (Figure 7b) showed altered Tg and Tm. Organo Bofe clay increased Tg, decreased Tm and Xc, whereas Organo Chocolate clay had the opposite effect, increasing Tm and Xc, and decreasing Tg. The addition of organoclay impacted PLA crystallization. Organo Chocolate clay reduced Tg, likely due to clay aggregation and PLA-clay adhesion. Organo Chocolate clay increased Tm and Xc, acting as a nucleation agent. Both clays reduced cold crystallization, likely due to exfoliated clays' high surface energy, creating nucleation sites [Alves ET AL., 2019]. The decrease in Xc of the PLA/Organo Bofe sample may result from adequate interfacial adhesion [Kim ET AL., 2010]. Organo Bofe clay increased Tg, suggesting that organoclay particles restrict PLA amorphous chain mobility [Perelomov ET AL., 2021]. In summary, Organo Bofe clay
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