Development and Characterization of PLA Composites with High Contents of a Brazilian Refractory Clay and Improved Fire Performance

Fabrication of a PLA/PVA-BIO-HA Polymeric Membrane by the Electrospinning Technique

“…The thermograms of the electrospun membranes of PLA, PVA-BIO-HA, and PL PVA-BIO-HA are shown in Figure 6. Figure 6a shows the thermogram of the PLA me brane, where a degradation step is observed, with a Tonset of 332 °C, attributed to the bre ing of bonds in the polymer structure leading to the release of gaseous products, such cyclic oligomers, acetaldehyde, lactide, and carbon monoxide [40], with a residue of 0 wt% at 1000 °C. The thermogram of PVA-BIO-HA membrane (Figure 6b) shows two gions of weight loss: the first from room temperature to 278 °C, attributed to the loss water or solvent residues, and the second within the interval 278-440 °C [41], wit The thermograms of the electrospun membranes of PLA, PVA-BIO-HA, and PLA/ PVA-BIO-HA are shown in Figure 6.…”

“…The thermogram of PVA-BIO-HA membrane (Figure 6b) shows two gions of weight loss: the first from room temperature to 278 °C, attributed to the loss water or solvent residues, and the second within the interval 278-440 °C [41], wit The thermograms of the electrospun membranes of PLA, PVA-BIO-HA, and PLA/ PVA-BIO-HA are shown in Figure 6. Figure 6a shows the thermogram of the PLA membrane, where a degradation step is observed, with a T onset of 332 • C, attributed to the breaking of bonds in the polymer structure leading to the release of gaseous products, such as cyclic oligomers, acetaldehyde, lactide, and carbon monoxide [40], with a residue of 0.77 wt% at 1000 • C. The thermogram of PVA-BIO-HA membrane (Figure 6b) shows two regions of weight loss: the first from room temperature to 278 • C, attributed to the loss of water or solvent residues, and the second within the interval 278-440 • C [41], with a residue of 4.92% at 1000 • C. The analysis of the thermal stability of the composite membrane PLA/PVA-BIO-HA shows a gradual decomposition process in four stages, as illustrated in Figure 6c. In the first stage, which takes place at temperatures below 100 • C, the loss is attributed to the elimination of absorbed moisture and solvents present in the membrane [39].…”

“…The second stage, which is in the range of 190 to 270 • C, is associated with the loss of low-molecular-weight substances, such as residual acetate groups, unconjugated polyenes, and water. The third stage corresponds to the loss of the main functional groups of the polymer, occurring in the range of 350 • C [40][41][42]. The fourth and final stage, at a temperature of 400 • C, includes the chemical elements that make up BIO-HA.…”

“…of the polymer, occurring in the range of 350 °C [40][41][42]. The fourth and final stage, at a temperature of 400 °C, includes the chemical elements that make up BIO-HA.…”

PLA Films Containing Montmorillonite Nanoclay–Citronella Essential Oil Hybrids for Potential Active Film Formulation

“…In this way, adding essential oil reduced the interaction betwe Regarding the second DSC heating ramp, the PLA melting temperature (Tm) curve indicates the presence of two stereoisomers of PLA, L-and D-lactic acid. The L (levogyre) and D (dextrogyre) form due to their polarized light effect [32,33]. Thus, the DSC curves, presented in Table 2, show the Tm values for each lactic acid in one of the chiral molecules; the melting temperature (Tm) PLLA is between 130 and 180 • C and that for PDLA is between 190 and 230 • C [31].…”