Impacts of rice husk ash filler loading on curing, morphological characteristics and tensile properties of natural rubber/ethylene propylene rubber blends

The rheometer curing curves of neat natural rubber (NR) and neat chloroprene rubber (CR) with maleide F (MF) exhibit considerable crosslinking torque at 180 °C. This indicates that MF can crosslink both these rubbers via Alder-ene reactions. Based on this knowledge, MF has been introduced as a co-crosslinking agent for a 50/50 blend of NR and CR in conjunction with accelerated sulfur. The delta (Δ) torque obtained from the curing curves of a blend with the addition of 1 phr MF was around 62% higher than those without MF. As the content of MF increased to 3 phr, the Δ torque was further raised to 236%. Moreover, the mechanical properties, particularly the tensile strength of the blend with the addition of 1 phr MF in conjunction with the accelerated sulfur, was around 201% higher than the blend without MF. The overall tensile properties of the blends cured with MF were almost retained even after ageing the samples at 70 °C for 72 h. This significant improvement in the curing torque and the tensile properties of the blends indicates that MF can co-crosslink between NR and CR via the Diels–Alder reaction.

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Effect of rice husk (treated/untreated) and rice husk ash on fracture toughness of epoxy bio-composite

Journal of the Mechanical Behavior of Materials ◽

10.1515/jmbm-2020-0018 ◽

2020 ◽

Vol 29 (1) ◽

pp. 177-185

Author(s):

Neeraj Bisht ◽

Prakash Chandra Gope

Keyword(s):

Fracture Toughness ◽

Epoxy Resin ◽

Rice Husk ◽

Rice Husk Ash ◽

Matrix Material ◽

Secondary Reinforcement ◽

Filler Loading ◽

Particle Reinforcement ◽

Pure Epoxy ◽

Fibre Treatment

AbstractPresent work studies the effect of particle reinforcement on fracture toughness of bio-composites. The filler used has been taken as rice husk. Epoxy resin has been taken as matrix material. Composites with varying filler loading of 10, 20, 30 and 40 wt.% were fabricated. The fracture toughness was seen to be increasing with increase in filler loading. However beyond 20% there was a decrease in fracture toughness with increase in filler loading. The effect of fibre treatment on toughness was also observed. Rice husk fibres pre-treated with NaOH were used. It was observed that fracture toughness further improved due to treatment. The increase in fracture toughness was significant. Fracture toughness increased from 1.072 to 2.7465 MPa√mm for 20% reinforcement and after treatment it increased to 2.876 MPa√mm. It was observed that concentration of treatment media also affects the fracture toughness. Further the effect of hybridization was observed by addition of rice husk ash as a secondary reinforcement. The fracture toughness of the resulting composites was remarkably higher than that of pure epoxy.

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Thermal oxidative stabilization of radiation-crosslinked polyethylene-ethylene propylene rubber blends

Journal of Polymer Science Polymer Symposia ◽

10.1002/polc.5070570109 ◽

2007 ◽

Vol 57 (1) ◽

pp. 73-80 ◽

Cited By ~ 2

Author(s):

G. Kammel ◽

R. Wiedenmann

Keyword(s):

Oxidative Stabilization ◽

Ethylene Propylene ◽

Rubber Blends ◽

Ethylene Propylene Rubber

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Tensile Properties and Dynamic Mechanical Behaviour of Natural Rubber Compound Filled with Rice Husk Silica Produced via Solvent-Thermal Extraction Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.947.195 ◽

2019 ◽

Vol 947 ◽

pp. 195-199

Author(s):

Zainathul Akhmar Salim Abdul Salim ◽

Aziz Hassan ◽

Hanafi Ismail ◽

Nor Hafizah Che Ismail

Keyword(s):

Natural Rubber ◽

Tensile Properties ◽

Rice Husk ◽

Mechanical Behaviour ◽

Extraction Method ◽

Silica Content ◽

Rice Husk Silica ◽

Dynamic Mechanical ◽

Thermal Extraction ◽

Rubber Filler

This study highlighted the effect of incorporation of rice husk silica (RHS) on the tensile properties and dynamic mechanical behaviour of natural rubber (NR) compounds. High purity RHS was synthesised by solvent-thermal extraction method, which was inspired by TAPPI T204 cm-97 and TAPPI T264 cm-97 standards with some modifications. The extraction method had successfully produced RHS with 99.9% of silica content and surface area of 234.25 m2/g. The incorporation of RHS in NR showed increment in tensile properties compared to unfilled NR. Further improvement was recorded by surface modification of RHS with 1 wt. % bis (triethoxysilylpropyl) tetrasulfide (TESPT). The modification of RHS with TESPT increased the rubber-filler interaction between RHS and NR matrix, hence enhancing the strength-related properties. The modified RHS-NR also recorded highest storage modulus, and the presence of RHS in the NR compound had slightly shifted the glass transition temperature (Tg) to a higher value. This confirmed that the strong rubber-filler interaction had increased the rigidity of the compounds and restricted the mobility of the rubber chains.

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