Effect of MWCNTs Functionalization on Thermal, Electrical, and Ammonia-Sensing Properties of MWCNTs/PMMA and PHB/MWCNTs/PMMA Thin Films Nanocomposites

Abstract

Partially biodegradable polymer nanocomposites Poly(3-Hydroxybutyrate) (PHB)/MultiwalledCarbon Nanotubes (MWCNTs)/Poly(Methyl Methacrylate) (PMMA)and non-biodegradable nanocomposites (MWCNTs/PMMA) were synthesized, and their thermal, electrical, and ammonia-sensing properties were compared. MWCNTs were chemically modified to ensure effective dispersion in the polymeric matrix. Pristine MWCNTs (p-MWCNTs) were functionalized with –COOH (a-MWCNTs) and amine groups (f-MWCNTs). Then, PHB grafted multiwalled carbon nanotubes (g-MWNTs) were prepared by a ‘grafting to’ technique. The p-MWCNTs, a-MWCNTs, f-MWCNTs, and g-MWCNTs were incorporated into the PMMA matrix and PMMA/PHB blend system by solution mixing. The PHB/f-MWCNTs/PMMA blend system showed good thermal properties among all synthesized nanocomposites. Results from TGA and dTGA analysis for PHB/f-MWCNTs/PMMA showed delay in T5 (about 127°C), T50 (up to 126°C), and Tmax (up to 65°C) as compared to neat PMMA. Higher values of frequency capacitance were observed in nanocomposites containing f-MWCNTs and g-MWCNTs as compared to nanocomposites containing p-MWCNTs and a-MWCNTs. This may be attributed to their excellent interaction and good dispersion in the polymeric blend. Analysis of ammonia gas-sensing data showed that PHB/g-MWCNTs/PMMA nanocomposites exhibited good sensitivity (≈100%) and excellent repeatability with a constant response. The calculated limit of detection (LOD) is 0.129 ppm for PHB/g-MWCNTs/PMMA, while that of all other nanocomposites is above 40 ppm.

Designing New Material Based on Functionalized Multi-Walled Carbon Nanotubes and Cu(OH)2–Cu2O/Polypyrrole Catalyst for Ethanol Oxidation in Alkaline Medium

“…The peak observed at 2366 cm −1 corresponds to the elongation vibration of the strongly hydrogenated -OH bond of the carboxylic groups (─COOH) as mentioned by Oularbi et al during the preparation of nanocomposites consisting of bismuth particles, polypyrrole, and multi-walled carbon nanotubes (Oularbi et al, 2019). Our results are in good agreement with those of the previous works in the literature confirming that the treated MWCNTs have been successfully oxidized with new functional groups on their surface (De et al, 2017;Adewoye et al, 2021;Qazi et al, 2021).…”

Structurally Stable, High-Strength Graphene Oxide/Carbon Nanotube/Epoxy Resin Aerogels as Three-Dimensional Skeletal Precursors for Wave-Absorbing Materials

“…Functionalized carbon nanotubes (FCNTs) were manufactured from carbon nanotubes (CNTs) [ 44 , 45 ]. 750 mL of concentrated H 2 SO 4 and 250 mL of HNO 3 were put into a three-necked flask containing 8 g of CNTs to stir with ultrasonic for 15 min, and then reflux at 100 °C for 8 h. After the reaction, the mixture was washed with deionized water until the pH was 7, and then functionalized carbon nanotubes (FCNTs) were obtained by freeze-drying.…”

Sensitive Cr3+ sensor based on novel poly(luminol-co-1,8-diaminonaphthalene)/CeO2/MWCNTs nanocomposites

“…This result suggests that the nanoller improved the thermal stability of the copolymer. 57,[73][74][75] Table 1 presents a comprehensive comparison of T 10 , T 25 , and T 50 , illustrating thermal decomposition at 10%, 25%, and 50%, respectively. The T 10 , T 25 , and T 50 values indicated a pattern performance controlled by the amount of MWCNTs loaded.…”