*Article* **Nanocomposite Materials Based on TMDCs WS<sup>2</sup> Modified Poly(L-Lactic Acid)/Poly(Vinylidene Fluoride) Polymer Blends**

**Mohammed Naffakh**

**Citation:** Naffakh, M.

Nanocomposite Materials Based on TMDCs WS<sup>2</sup> Modified Poly(L-Lactic Acid)/Poly(Vinylidene Fluoride) Polymer Blends. *Polymers* **2021**, *13*, 2179. https://doi.org/10.3390/ polym13132179

Academic Editors: José Miguel Ferri, Vicent Fombuena Borràs and Miguel Fernando Aldás Carrasco

Received: 14 June 2021 Accepted: 28 June 2021 Published: 30 June 2021

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Escuela Técnica Superior de Ingenieros Industriales, Universidad Politécnica de Madrid (ETSII-UPM), José Gutiérrez Abascal 2, 28006 Madrid, Spain; mohammed.naffakh@upm.es

**Abstract:** Novel multifunctional biopolymer blend nanocomposites composed of poly(vinylidene fluoride)(PVDF) and tungsten disulfide nanotubes (INT-WS<sup>2</sup> ) that are layered transition metal dichalcogenides (TMDCs) were easily prepared by applying an economical, scalable, and versatile melt processing route. Furthermore, their synergistic effect to enhance the properties of poly(L-lactic acid) (PLLA) matrix was investigated. From morphological analysis, it was shown that the incorporation of 1D (INT)-WS<sup>2</sup> into the immiscible PLLA/PVDF mixtures (weight ratios: 80/20, 60/40, 40/60, and 20/80) led to an improvement in the dispersibility of the PVDF phase, a reduction in its average domain size, and consequently a larger interfacial area. In addition, the nanoparticles INT-WS<sup>2</sup> can act as effective nucleating agents and reinforcing fillers in PLLA/PVDF blends, and as such, greatly improve their thermal and dynamic-mechanical properties. The improvements are more pronounced in the ternary blend nanocomposites with the lowest PVDF content, likely due to a synergistic effect of both highly crystalline PVDF and 1D-TMDCs nano-additives on the matrix performance. Considering the promising properties of the developed materials, the inexpensive synthetic process, and the extraordinary properties of environmentally friendly and biocompatibe 1D-TMDCs WS<sup>2</sup> , this work may open up opportunities to produce new PLLA/PVDF hybrid nanocomposites that show great potential for biomedical applications.

**Keywords:** TMDCs-WS<sup>2</sup> ; PLLA; PVDF; nanomaterials; morphology; crystallization; dynamicmechanical properties
