Fly ash particles and precipitated silica as fillers in rubbers. I. Untreated fillers in natural rubber and styrene-butadiene rubber compounds

In recent years, automotive hose and belt specifications have changed, requiring longer product life in terms of swelling, wear and heat ageing. Diene-based rubbers, such as natural rubber (NR) and styrene-butadiene rubber (SBR), have been widely used in diverse industries. However, some apparent defects such as limited ageing resistance and large compression set, have been demonstrated in some rubbers cured by sulfur or peroxides. In the making of general and industrial rubber goods, short production and sufficient scorch time is crucial especially by using an injection moulding. In this work, blend of Epoxidised Natural Rubber (ENR 25) and Butadiene was developed with two types of curing systems namely Conventional and Efficient Vulcanisation system. The aim of the study is to produce a satisfactory heat resistance rubber compounds and adequate process safety for rubber manufacturing. Results showed that curing system applied significantly affected thermal stability property of the compounds. Modulus and hardness of the blends appeared to decrease progressively with ageing. However, greater thermal stability especially ageing at 100°C for 200h was observed with compound containing efficient curing system compared to conventional curing system which corresponded to the cross link density attributed by the torque value and dynamic mechanical analysis. The results on stiffness however was effected by the curing system applied. The influence of cure temperature on the chemical crosslink density on both cure systems are being investigated. The network results will be correlated with the technical properties.

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Influence of Mixing Procedure on Properties of Silica Filled Epoxidised Natural Rubber Compounds

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1024.175 ◽

2014 ◽

Vol 1024 ◽

pp. 175-178

Author(s):

Mazlina Mustafa Kamal ◽

Dayang Habibah Abang Asmawi

Keyword(s):

Natural Rubber ◽

Rolling Resistance ◽

High Viscosity ◽

Raw Material ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Precipitated Silica ◽

Rubber Compounds ◽

Dispersion Agent ◽

Mooney Viscosity

Since the introduction of the so-called Green Tyre concept, in the early 90ies, the use of silica as reinforcing fillers has spread and grown worldwide. The general advantages of silica as reinforcing filler over carbon black filler are better rolling resistance by achieving at least equal wet traction while tread wear should not be adversely affected. One way to obtain both low rolling resistance and high wet traction is indeed, to use precipitated silica together with solution polymers in tyre treads. The benefits of reinforcement by silane coupled silicas, in certain blends of solution styrene –butadiene rubber (SBR) and butadiene rubber (BR), were recognized by major tyre manufacturer. However, the use of silica compounds entails considerable disadvantages in terms of raw material costs and processability (before vulcanization). These difficulties include higher compound Mooney Viscosity (ML1+4) that increases upon storage, short scorch time and environmental problems related to alcohol evolution. The high viscosity and poor processability in silica filled rubber compounds are believed to be associated with silica reaggregation (self aggregation) after rubber compounding. The study has been made of the effect of increased mixing stage and dispersion agent in rubber on uncured properties of the Silica Filled Epoxidised Natural Rubber Compounds. In this experiment, two orders of mixing were considered (1) Two Stages Mixing and (2) Three Stages Mixing. Results showed that filler dispersion, Mooney Viscosity and Payne Effect was influenced by the degree of mixing. The incorporation of dispersion agents in the compounds also resultant in the similar manner. It is believed that the dispersion agent could coat the silica surfaces as they are being broken down during the mixing and then stabilize the dispersed structure by stearically preventing silica reagglomeration.

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Use of natural rubber prophylactics waste as a potential filler in styrene-butadiene rubber compounds

Journal of Applied Polymer Science ◽

10.1002/(sici)1097-4628(19960912)61:11<2035::aid-app19>3.0.co;2-7 ◽

1996 ◽

Vol 61 (11) ◽

pp. 2035-2050 ◽

Cited By ~ 33

Author(s):

George Mathew ◽

R. P. Singh ◽

R. Lakshminarayanan ◽

Sabu Thomas

Keyword(s):

Natural Rubber ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Rubber Compounds ◽

Styrene Butadiene

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Investigation of correlation between rheological properties of rubber compounds based on natural rubber/styrene-butadiene rubber with their thermal behaviors

International Journal of Industrial Chemistry ◽

10.1186/2228-5547-4-16 ◽

2013 ◽

Vol 4 (1) ◽

pp. 16 ◽

Cited By ~ 7

Author(s):

Fereshteh Motiee ◽

Saeed Taghvaei-Ganjali ◽

Mercedeh Malekzadeh

Keyword(s):

Natural Rubber ◽

Rheological Properties ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Thermal Behaviors ◽

Rubber Compounds ◽

Styrene Butadiene

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CURE CHARACTERISTICS AND CROSSLINK DENSITY OF NATURAL RUBBER/STYRENE BUTADIENE RUBBER BLENDS

Jurnal Teknik Kimia USU ◽

10.32734/jtk.v3i4.1644 ◽

2015 ◽

Vol 3 (4) ◽

pp. 1-5

Author(s):

Indra Surya ◽

Syahrul Fauzi Siregar

Keyword(s):

Natural Rubber ◽

Crosslink Density ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Blend Ratio ◽

Rubber Blends ◽

Cure Characteristics ◽

Rubber Compounds ◽

Cure Time ◽

Styrene Butadiene

By using a semi-efficient vulcanization system, the cure characteristics and crosslink density of natural rubber/styrene butadiene rubber (NR/SBR) blends were studied with a blend ratio from 0 to 100% rubber. The scorch time, optimum cure time, and torque difference value of the blended rubber compounds were determined by using the Moving-Die Rheometer (MDR 2000). The crosslink density was determined by the Flory—Rehner approach. Results indicate that the scorch and cure times, ts2 and t90, of the NR/SBR blends increased with increasing the SBR content. Whilst, the maximum values of torque difference and crosslink density were performed by the NR/SBR blend with a blend ratio of 75/25.

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Hybrid Silica-Based Fillers in Nanocomposites: Influence of Isotropic/Isotropic and Isotropic/Anisotropic Fillers on Mechanical Properties of Styrene-Butadiene (SBR)-Based Rubber

Polymers ◽

10.3390/polym13152413 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2413

Author(s):

Mariapaola Staropoli ◽

Vincent Rogé ◽

Enzo Moretto ◽

Joffrey Didierjean ◽

Marc Michel ◽

...

Keyword(s):

Mechanical Properties ◽

Silica Nanoparticles ◽

Synergetic Effect ◽

Mechanical Analysis ◽

Rubber Matrix ◽

Styrene Butadiene Rubber ◽

Butadiene Rubber ◽

Precipitated Silica ◽

Scanning Transmission ◽

Styrene Butadiene

The improvement of mechanical properties of polymer-based nanocomposites is usually obtained through a strong polymer–silica interaction. Most often, precipitated silica nanoparticles are used as filler. In this work, we study the synergetic effect occurring between dual silica-based fillers in a styrene-butadiene rubber (SBR)/polybutadiene (PBD) rubber matrix. Precipitated Highly Dispersed Silica (HDS) nanoparticles (10 nm) have been associated with spherical Stöber silica nanoparticles (250 nm) and anisotropic nano-Sepiolite. By imaging filler at nano scale through Scanning Transmission Electron Microscopy, we have shown that anisotropic fillers align only in presence of a critical amount of HDS. The dynamic mechanical analysis of rubber compounds confirms that this alignment leads to a stiffer nanocomposite when compared to Sepiolite alone. On the contrary, spherical 250 nm nanoparticles inhibit percolation network and reduce the nanocomposite stiffness.

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