Influence of modifying organoclay on the properties of natural rubber/organoclay nanocomposites

Abstract

Montmorillonite nanoclay was modified with octadecylamine and compounded with natural rubber by the melt mixing method. Influence of the modification on the properties of natural rubber/organoclay nanocomposites was investigated. Furthermore, structures of the natural rubber/clay nanocomposites were characterized by X-ray diffraction and scanning electron microscopy. It was found that organoclay was well dispersed in the natural rubber matrix. Curing characteristics of the rubber compound indicated that octadecylamine modification accelerated the vulcanization reaction of natural rubber and caused a higher degree of crosslinking. The storage modulus (E′) of the natural rubber vulcanizates was higher with the modified clay than with unmodified montmorillonite (Na-MMT). The effects on the storage modulus are more pronounced at temperatures above the melting temperature of octadecylamine. The low thermal stability of this modifying agent does not affect the thermal stability of the natural rubber/organoclay nanocomposite.

Keywords

Natural rubber sodium montmorillonite organoclay activation energy nanocomposites

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References

López-Manchado

Herrero

Arroyo

. Organoclay–natural rubber nanocomposites synthesized by mechanical and solution mixing methods. Polym Int 2004; 53: 1766–1772.

Yahaya

Adebowale

Menon

ARR

. Mechanical properties of organomodified kaolin/natural rubber vulcanizates. Appl Clay Sci 2009; 46: 283–288.

Gao

Song

. Octadecylammonium montmorillonite/natural rubber/cis-1,4-polybutadiene nanocomposites. Appl Clay Sci 2010; 50: 143–147.

Tabsan

Wirasate

Suchiva

. Abrasion behavior of layered silicate reinforced natural rubber. Wear 2010; 269: 394–404.

Carli

Roncato

Zanchet

. Characterization of natural rubber nanocomposites filled with organoclay as a substitute for silica obtained by the conventional two-roll mill method. Appl Clay Sci 2011; 52: 56–61.

Magaraphan

Thaijaroen

Lim-ochakun

. Structure and properties of natural rubber and modified montmorillonite nanocomposites. Rubber Chem Technol 2003; 76: 406–418.

Song

Liu

. Preparation and properties of organo-montmorillonite/cis-1, 4-polybutadiene rubber nanocomposites by solution intercalation. Appl Clay Sci 2009; 45: 50–53.

Soares

De Oliveira

Zaioncz

. Nitrile rubber/organomontmorillonite nanocomposites produced by solution and melt compounding: effect of the polarity of the quaternary ammonium intercalants. J Appl Polym Sci 2010; 119: 505–514.

Wang

Zhang

. Rubber–pristine clay nanocomposites prepared by co-coagulating rubber latex and clay aqueous suspension. Compos Sci Technol 2005; 65: 1195–1202.

10.

Valadares

Leite

CAP

Galembeck

. Preparation of natural rubber–montmorillonite nanocomposite in aqueous medium: evidence for polymer–platelet adhesion. Polymer 2006; 47: 672–678.

11.

Jia

Wang

. Enhanced interfacial interaction of rubber/clay nanocomposites by a novel two-step method. Compos Sci Technol 2008; 68: 1050–1056.

12.

Wang

. Preparation, structure, performance, industrialisation and application of advanced rubber/clay nanocomposites based on latex compounding method. Plast Rubber Compos 2010; 39: 33–42.

13.

Bala

Samantaray

Srivastava

. Organomodified montmorillonite as filler in natural and synthetic rubber. J Appl Polym Sci 2004; 92: 3583–3592.

14.

Zheng

Zhang

Peng

. Influence of clay modification on the structure and mechanical properties of EPDM/montmorillonite nanocomposites. Polym Test 2004; 23: 217–223.

15.

Das

Costa

Wagenknecht

. Nanocomposites based on chloroprene rubber: effect of chemical nature and organic modification of nanoclay on the vulcanizate properties. Eur Polym J 2008; 44: 3456–3465.

16.

Arroyo

López-Manchado

Herrero

. Organo-montmorillonite as substitute of carbon black in natural rubber compounds. Polymer 2003; 44: 2447–2453.

17.

López-Manchado

Arroyo

Herrero

. Vulcanization kinetics of natural rubber–organoclay nanocomposites. J Appl Polym Sci 2003; 89: 1–15.

18.

Avalos

Ortiz

Zitzumbo

. Effect of montmorillonite intercalant structure on the cure parameters of natural rubber. Eur Polym J 2008; 44: 3108–3115.

19.

Carretero-González

Retsos

Verdejo

. Effect of nanoclay on natural rubber microstructure. Macromolecules 2008; 41: 6763–6772.

20.

Hernández

Carretero-González

Verdejo

. Molecular dynamics of natural rubber/layered silicate nanocomposites as studied by dielectric relaxation spectroscopy. Macromolecules 2010; 43: 643–651.

21.

Ghosh

Katare

Patkar

. Sulfur vulcanization of natural rubber for benzothiazole accelerated formulations: from reaction mechanisms to a rational kinetic model. Rubber Chem Technol 2003; 76: 592–693.

22.

Ding

Leonov

Coran

. A study of the vulcanization kinetics of an accelerated-sulfur SBR compound. Rubber Chem Technol 1996; 69: 81–91.