Multiwalled carbon nanotubes cnts

Multiwalled carbon nanotubes (CNTs) with average diameter/length of 9.5 nm/1.5 μm, respectively, and carboxylic acid functionalization were purchased at Sigma-Aldrich S.r.l. (Milan, Italy). The –COOH functional groups present on carbon nanotubes allow to get a better dispersion in solution. A 2.5 wt. % dispersion of crystalline ZnO (hexagonal wurtzite) nanoparticles in isopropanol was supplied by Avantama AG (Stafa, Switzerland). The average diameter of the ZnO nanoparticles is about 15 nm.

Commercially obtained Epikote-1001 x-75% (2642) epoxy together with crayamid – 100% (2580) epoxy hardener was applied as pure epoxy resin; they were also used as obtained without additional purification. Epikote : crayamid (1 : 1) weight by weight was adjusted as exact mixing ratio for pure epoxy processing and fabrication. Spectroscopic grade chloroform was obtained from Sigma-Aldrich, and it was also used without any additional purification. Furthermore, multi-walled carbon nanotubes (CNTs) with an average diameter of 110.0–170.0 nm were purchased from Sigma-Aldrich, and they were used as received without any purification. More particularly, graphene nano-platelet (GNP) was also purchased from Sigma-Aldrich and used as received. Any other chemicals or materials used were of high purity and were also obtained from known sources; they were used as obtained without further purifications, including Spectroscopic grade chloroform from Sigma-Aldrich.

Multi-walled carbon nanotubes (CNTs) were purchased from Sigma-Aldrich (St. Louis, MO, USA) (product number: 791431, lot MKBT4011V) and used as received. Methyl 2-bromopropionate (MBP, Sigma-Aldrich (St. Louis, MO, USA), ≥99%), styrene (Sigma-Aldrich (St. Louis, MO, USA), ≥99%), N,N,N′,N′′,N′′-pentamethyldiethylenetriamine (PMDETA, Sigma-Aldrich(St. Louis, MO, USA), 99%), anisole (Sigma-Aldrich (St. Louis, MO, USA), 99.7%), glacial acetic acid, methanol, dioxane, tetrahydrofuran (THF), dimethylformamide (DMF), ethanol, ethyl acetate and 1,4-diazabicyclo[2.2.2]octane (Sigma-Aldrich, analytical grade) were used without any purification. Tert-butyl acrylate (Sigma-Aldrich (St. Louis, MO, USA), 98%) was purified over a column of basic aluminum oxide and stored under nitrogen before use. Copper(I)bromide (Sigma-Aldrich (St. Louis, MO, USA), 99%) and copper(I)chloride (Sigma-Aldrich (St. Louis, MO, USA), 99%) were stirred in glacial acetic acid for 5 h, filtered, washed with acetic acid, ethanol and ethyl acetate and dried under vacuum before use.

LDPE used in the composite films was procured from Qatar Petrochemical Company (QAPCO). Titanium (IV) oxide anatase nanopowder (TONPs) (particle size of 15 nm, 232033) and multi-walled carbon nanotubes (CNTs; outer diameter × length: 6–9 nm × 5 µm; bulk density of 0.22 kg/m³; <95% carbon; 724769-25G) were obtained from Sigma-Aldrich (Saint Louis, MO, USA). All materials were used without any treatment.