Understanding the Coupling Effect between Lignin and Polybutadiene Elastomer

Abstract

From an environmental and economic viewpoint, it is a win–win strategy to use materials obtained from renewable resources for the production of high-performance elastomer composites. Lignin, being a renewable biomass, was employed as a functional filler material to obtain an elastomer composite with a higher degree of mechanical performance. In the presence of a suitable coupling agent, an elevated temperature was preferred for the reactive mixing of lignin with polybutadiene rubber (BR). It is quite fascinating that the mechanical performance of this composite was comparable with carbon black-filled composites. The extraordinary reinforcing behavior of lignin in the BR matrix was understood by an available model of rubber reinforcement. In rubber composite preparation, the interfacial interaction between polybutadiene rubber and lignin in the presence of a coupling agent enabled the efficient dispersion of lignin into the rubber matrix, which is responsible for the excellent mechanical properties of the rubber composites. The rubber composites thus obtained may lead to the development of a sustainable and cost-effective end product with reliable performance. This novel approach could be implemented in other type of elastomeric materials, enabling a genuine pathway toward a sustainable globe.

Mechanical Properties and Equilibrium Swelling Characteristics of Some Polymer Composites Based on Ethylene Propylene Diene Terpolymer (EPDM) Reinforced with Hemp Fibers

“…It can be observed that the value of parameter a is twice the value of parameter b , making evident the good interaction between rubber and the reinforcing agent. As can be observed from Figure 4 , the combination of the high values of a with lower values of b leads to strong filler–EPDM rubber interactions [ 32 , 63 ], which is in agreement with the results obtained using the Kraus relation.…”

“…The value of m can be obtained from the slope of V ro /V rf as a function of Φ/(1−Φ). The interaction constant between rubber and filler, C, can be estimated from Equation (9) [ 32 ]. …”

“…The extent of interactions between EPDM rubber and hemp fibers can be analyzed using the Lorenz–Park Equation (10) [ 32 , 61 , 62 ]. where z is the weight fraction of fiber in the polymer, a and b are constants, Q f and Q s represent the amount of solvent absorbed per unit weight of rubber and filled material, respectively, and they are obtained using Equation (11) [ 32 ]. where m s and m d are the swollen and dried weight of the compound.…”

“…The volume fraction of rubber in the swollen sample V ro for rubber composites that do not contain reinforcing agent can be estimated by the Equation (3) [ 31 , 32 ]. where ρ s represents the solvent density, ρ r is rubber sample density and ( m s −m d ) is the weight of solvent in the swollen rubber.…”

A Review of Rubber Biocomposites Reinforced with Lignocellulosic Fillers

“…Additionally, some examples are described in more detail in Table 8. Other studies also used BR [170][171][172], SR [173][174][175][176][177], EPDM [178,179] and EVA [180], as well as rubber blends such as NR/SBR [181][182][183][184][185][186], NR/NBR [187], NR/SBR/BR [188,189], NR/BR [190], NR/EVA [191] and SBR/NBR [192] as a matrix for lignocellulosic-based rubber composites.…”