Simultaneous Enhancement of Strength and Toughness of PLA Induced by Miscibility Variation with PVA

Abstract

The mechanical properties of poly (lactic acid) (PLA) nanofibers with 0%, 5%, 10%, and 20% (w/w) poly (vinyl alcohol) (PVA) were investigated at the macro- and microscale. The macro-mechanical properties for the fiber membrane revealed that both the modulus and fracture strain could be improved by 100% and 70%, respectively, with a PVA content of 5%. The variation in modulus and fracture strain versus the diameter of a single electrospun fiber presented two opposite trends, while simultaneous enhancement was observed when the content of PVA was 5% and 10%. With a diameter of 1 μm, the strength and toughness of the L95V5 and L90V10 fibers were enhanced to over 3 and 2 times that of pure PLA, respectively. The structural evolution of electrospun nanofiber was analyzed by differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Although PLA and PVA were still miscible in the concentration range used, the latter could crystallize independently after electrospinning. According to the crystallization behavior of the nanofibers, a double network formed by PLA and PVA—one microcrystal/ordered structure and one amorphous structure—is proposed to contribute to the simultaneous enhancement of strength and toughness, which provides a promising method for preparing biodegradable material with high performance.

Manufacturing and Characterization of Functionalized Aliphatic Polyester from Poly(lactic acid) with Halloysite Nanotubes

“…Above all these polymers, it is worthy to note the current interest of poly(lactic acid)—PLA, which can be obtained by starch fermentation and, subsequently, polymerization. PLA and its blends have gained a privileged position in the polymer industry as it shows balanced properties (mechanical, thermal, barrier, physical and so on) with an everyday most competitive price [29,30,31]. Today it is possible to find PLA in a wide variety of industrial applications that include automotive, construction and building, packaging, houseware and so on [32,33,34,35,36], Behera et al [37] proposed that by controlling the manufacturing process, the properties of PLA could be tailored e.g., by lowering M w and the glass transition temperature (T g ).…”

Polylactide/Polyvinylalcohol-Based Porous Bioscaffold Loaded with Gentamicin for Wound Dressing Applications

“…The two peaks around 1448 and 1373 cm −1 correspond to the methyl groups of the PLA-PVA bioscaffolds. Moreover, the high-intensity peak that is positioned at 3399 cm −1 corresponds to the stretching vibration of the oxygen-hydrogen bond (O-H) [ 12 , 42 , 43 ]. Figure 2 A, illustrates that the intensity and position of the absorption peak of the hydroxyl group changed with the addition of salts and thermal treatment.…”

“…PVA is a synthetic biocompatible polymer widely used in biomedical applications [ 11 ]. It is an excellent choice for improving the properties of PLA due to its nontoxicity, hydrophilicity, low cost, and ease of processing [ 12 , 13 ]. Ribba et al fabricated PLA-PVA films for wound dressing applications, which exhibited good stability over time, humidity control, and biocompatibility [ 14 ].…”

Effect of introduction of tetrabutylammonium bromide on properties of poly (L‐lactic acid) tubular scaffold prepared by electrospinning

“…However, the PLA fibres prepared by electrospinning have low crystallinity [6], which results in low mechanical strength that limits its application. Consequently, many researchers have focused on the improvement of the mechanical properties of electrospun PLA fibres, developing approaches such as addition of nanoparticles [7], GO nanosheets [8] or PVA [9] to the spinning solution or adjusting the spinning parameters. Stretching in the processing of polymers has been revealed as an effective method to enhance their mechanical properties.…”