*Article* **Modification of Polylactide Nonwovens with Carbon Nanotubes and Ladder Poly(silsesquioxane)**

**Mariia Svyntkivska, Tomasz Makowski \*, Ewa Piorkowska, Marek Brzezinski, Agata Herc and Anna Kowalewska**

> Centre of Molecular and Macromolecular Studies Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland; mariiasv@cbmm.lodz.pl (M.S.); epiorkow@cbmm.lodz.pl (E.P.); mbrzezin@cbmm.lodz.pl (M.B.); asherc@cbmm.lodz.pl (A.H.); anko@cbmm.lodz.pl (A.K.) **\***

Correspondence: tomekmak@cbmm.lodz.pl

**Abstract:** Electrospun nonwovens of poly(L-lactide) (PLLA) modified with multiwall carbon nanotubes (MWCNT) and linear ladder-like poly(silsesquioxane) with methoxycarbonyl side groups (LPSQ-COOMe) were obtained. MWCNT and LPSQ-COOMe were added to the polymer solution before the electrospinning. In addition, nonwovens of PLLA grafted to modified MWCNT were electrospun. All modified nonwovens exhibited higher tensile strength than the neat PLA nonwoven. The addition of 10 wt.% of LPSQ-COOMe and 0.1 wt.% of MWCNT to PLLA increased the tensile strength of the nonwovens 2.4 times, improving also the elongation at the maximum stress.

**Keywords:** polylactide nonwovens; electrospinning; reinforced fibers; MWCNT; linear ladder-like poly(silsesquioxane)

**Citation:** Svyntkivska, M.; Makowski, T.; Piorkowska, E.; Brzezinski, M.; Herc, A.; Kowalewska, A. Modification of Polylactide Nonwovens with Carbon Nanotubes and Ladder Poly(silsesquioxane). *Molecules* **2021**, *26*, 1353. https:// doi.org/10.3390/molecules26051353

Academic Editors: Dimitrios Bikiaris, Marek Brzezi ´nski and Małgorzata Ba´sko

Received: 1 February 2021 Accepted: 21 February 2021 Published: 3 March 2021

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