Improving stability of mechanical properties for nitrile butadiene rubber composite by carbon nanotube with antioxidant loading distribution

Abstract

Antioxidants are necessarily used in nitrile butadiene rubber (NBR) products to prolong their lifetimes. But blooming of antioxidants limits the anti‐aging efficiency. Herein, a novel solution was proposed to avoid such a blooming. Antioxidant, 3, 9‐bis‐{1, 1‐dimethyl‐2(β‐[3‐tert‐butyl‐4‐hydroxy‐5‐methylphenyl‐] propionyloxy) ethyl}‐2, 4, 8, 10‐tetraoxaspiro [5, 5]‐undecane (AO‐80) was loaded to carbon nanotubes (CNTs) by chemically grafting after shearing force and then physically melting to encapsulate. In the AO‐80 loaded CNTs (CNT‐AO80), physical loading amounts of antioxidants were 2.1% and strongly suppressed by those parts from chemically grafting (13.9%), developing a distribution around CNTs. CNT‐AO80 therefore maintained a high total loading efficiency of antioxidant and reduced its physical release amounts not to bloom. When 20 phr CNT‐AO80 were doped to NBR, they allowed a good dispersity and reinforcement for rubber matrix. After thermal‐oxidative aging at 70, 80, and 90°C for 60 days, the composite gave an extremely low deterioration of mechanical property. POLYM. COMPOS., 40:E1172–E1180, 2019. © 2018 Society of Plastics Engineers

Effect of hybrid carbon black/lignin on rheological, mechanical and thermal stability properties of NR/BR composites

“…The increasing M100 values of the samples after hot air aging was due to the phenolic structure of lignin, as shown in Figure 5, which protected the NR/BR from degradation due to hot aging. Generally, the chain scission of natural rubber happens due to a hot environment and the macro-radical reaction that occurs with the unsaturated double bonds (C = C), thus resulting in the deterioration of the strength characteristics [47]. Hence, the addition of lignin can act as a stabiliser in oxidative reactions and may contribute to more stability during the service life under heat.…”

“…The unsaturated backbone of the NR was easily broken down due to environmental stresses such as attack by oxygen molecules, especially at high temperatures [46]. This phenomenon led to scission of the long molecular chains and reduced the molecular weight of the rubber chains, thereby resulting in less entanglements [47]. Therefore, the ability of the rubber matrix to transfer stress was reduced, thus decreasing the rupture resistance.…”

Improving thermal‐oxidative stability of nitrile butadiene rubber composites by surface modification of zirconium phosphate

“…[10,11] However, most of the antioxidants currently being used are organic small molecules, which is easy to migrate away from rubber, leading to poor aging resistance, and also prone to cause environmental pollution. [12,13] Therefore, it is meaningful to prepare an efficient and green antioxidant filler for rubber.…”

Molecular dynamics simulations of defective carbon nanotubes on the aging and friction properties of nitrile butadiene rubber composites

“…[12,13] To reduce the migration of antioxidants within the rubber matrix while enhancing the aging and mechanical properties of NBR, CNTs have been incorporated in antioxidant/rubber composites. Zhang et al [14] studied the effect of CNTs with antioxidants on the aging properties of NBR composites by incorporating the antioxidant AO-80 into CNTs. The NBR composites containing CNT/AO80 exhibited good resistance to TOA.…”