Silica‐filled NR compounds prepared by dry and wet masterbatches with different mixing times

Abstract

Silica‐filled NR compounds are prepared by mixing rubber with organic‐networked silica and additives such as curatives, processing and coupling agents, and stabilizer in a dried state (dry‐mixed NR, DNR) and mixing a silica‐NR wet masterbatch prepared in liquid phase with the additives (wet‐mixed NR, WNR). The effects of mixing method and time of DNR and WNR compounds on their cure, process, tensile, and dynamic properties are investigated. The mixing of DNR crushes silica aggregates to smaller ones, but also forms occasionally large ones, while the mixing of WNR produces small aggregates without forming larger ones because silica aggregates are already covered with rubber. The high silica dispersion, suppressed silica aggregation, low Payne effect, and low‐loss modulus of the WNR compounds prepared by mixing for a sufficient time result in their low viscosity, high scorch safety, and low rolling resistance without sacrificing other rubber properties.

Effects of cellulose nanocrystals on the vulcanization of natural rubber/cellulose nanocrystals nanocomposite and corresponding regulating strategies

“…ρ 1 is 0.865 g/cm 3 , V 1 is 106.3 cm 3 /mol, and the interaction parameter (χ) of NR with toluene is 0.413. 34 3 | RESULTS AND DISCUSSION As indicated in the FTIR spectrum of CNCs (Figure 1(B)), the typical characteristic peaks at 3370, 1641, and 813 cm À1 are corresponding to the stretching vibration of hydroxyl groups, the bending vibration of hydroxyl groups and the vibration of sulfonate, respectively. 35 The existence of these characteristic peaks indicates that CNCs have strong hydrophilicity.…”

Naturally occurring halloysite nanotubes for enhanced durability of natural rubber/ethylene propylene diene monomer rubber vulcanizate

“…This is because a fairly low CRI formulation provides sufficient time to conduct the necessary mixing without the risk of precuring. [34] The belated vulcanization of rubber by incorporation of natural [22,25,55,56] Abbreviations: GNP, graphene nanoparticles; NC, nanoclay; R-PET: recycled polyethylene terephthalate.…”

Preparation of Natural Rubber Composites with High Silica Contents Using a Wet Mixing Process

“…Recently, Ryu et al prepared a 50 phr nanosilica/rubber composite. The effects of the mixing time in a dry mixer were the main focus of that study . The addition of a second filler was applied in the wet mixing process by Wang et al who studied a 50 phr silica-filled natural rubber, using nanosilica modified with reduced graphene oxide.…”

“…Therefore, an appropriate method is necessary for dispersing the silica prior to mixing with the rubber latex. In the laboratory scale, an agitator bead mill and an ultrasonic dispersion machine are often used to prepare silica dispersions. ,,, However, these devices are not suitable for industrial-scale production because of high operating costs and difficulties in scale-up. Ball milling, in contrast, is easily scaled up to industrial size.…”