Polybutadiene Rubber/Graphene Nanocomposites Prepared via In Situ Coordination Polymerization Using the Neodymium-Based Ziegler–Natta Catalyst

Abstract

In the present study, we report the fabrication of polybutadiene rubber (PBR)/graphene nanosheet (GNS) nanocomposites using in situ polymerization. For the catalyst system, we chose neodymium versatate (NdV3) as the catalyst, triethylaluminum as the cocatalyst or activator, and ethylaluminum sesquichloride as the chloride donor in the presence of GNSs. The effects of GNSs on the activity of the catalyst, chain microstructure, structural, morphological, and thermal properties of the nanocomposites have been investigated. The morphology, structural properties, and the state of dispersion of graphene nanoplatelets in the PBR matrix have been characterized by X-ray diffraction spectroscopy, scanning electron microscopy, and transmission electron microscopy which showed dispersion of the individual layers (highly exfoliated) of graphene in the PBR matrix. Thermal properties of nanocomposites have been studied by differential scanning calorimetry (DSC) and thermogravimetric analysis. DSC results indicated that the addition of small amounts of well-dispersed graphene significantly increased the glass transition temperature (T g) owing to restricted motion of rubber chains physically adsorbed or wrapped to graphene surfaces because of π–π and CH−π interactions. The incorporation of GNSs enhanced the thermal stability and char yield of the nanocomposites. Based on these results, in situ polymerization mainly paves the way to prepare graphene-based nanocomposites of rubbers with good properties and high performance.

The Impacts of Polyisoprene Physical Interactions on Sorting of Single‐Wall Carbon Nanotubes

“…This phenomenon could be attributed to the -stacking between the PI double bond and SWCNTs aromatic ring. [15,25] Additionally, as shown in Raman analysis (Figure 5d), the G-band peaks at 1583 cm −1 for the pristine SWCNTs and at 1605 cm −1 for PFO 12k -b-PI sample were shifted to a different frequency at 1589 cm −1 in the SWCNTs-PFO 12k -b-PI sample that is related to -interactions between the PFO and PI segment to benzene rings of SWCNTs. Furthermore, SWCNTs-PFO 12k sample displays small G-band peak shifting (1583-1584 cm −1 ), unlike the SWCNTs-PFO 12k -b-PI sample (1583-1589 cm −1 ) indicating the effect of PI interaction.…”

“…Furthermore, SWCNTs-PFO 12k sample displays small G-band peak shifting (1583-1584 cm −1 ), unlike the SWCNTs-PFO 12k -b-PI sample (1583-1589 cm −1 ) indicating the effect of PI interaction. [15] However, the -stacking from the PI chain is not strong enough to efficiently bind SWCNT as evidenced by awful performance of PI in the sorting process. Therefore, these results in FTIR and Raman spectroscopies were found very consistent for verifying the participation of the PI physical bond in assisting for stronger binding of diblock polymer-based PFO 12k toward SWC-NTs.…”

“…Polyisoprene (PI), a major constituent of the natural rubber, may form physical crosslinking especially through VDW, [14] and -stacking [15] with other carbon materials, [14c,16] and due to inheritance of pure hydrocarbon with longer chain-length in its structure, PI can be a viable candidate in potentially generating stronger VDW interaction with dispersed nanotubes than normal alkyl side chains of the conjugated polymers. This is especially possible since SWCNTs had been shown to form VDW with other materials.…”

Graphene in rubber formulations: a comprehensive review and performance optimization insights

“…63,86,158 Recently, researchers have actively introduced graphene as a filler in the tire formulation to improve the life span, abrasion resistance, and heat buildup in the tire to reduce the unrecyclable tire waste that will pollute the environment. 65,69,135,159…”

“…Thermogravimetric analysis indicates that the degradation temperature of graphene nanosheet/polybutadiene rubber increased by ∼10% owing to the well-dispersed graphene nanosheet with high barrier properties to hinder the access of hot gas. 159…”