Natural rubber latex-clay nanocomposite: use of montmorillonite clay as an alternative for conventional CaCO3

Abstract

Natural rubber (NR) latex-clay nanocomposite (NRLCN) synthesized with montmorillonite (MMT) clay aqueous dispersion was evaluated for reinforcement and barrier properties. The physio-mechanical properties of the NRLCN were compared with the conventional NR latex composites containing CaCO 3. The NRLCN structure was characterized with X-ray diffraction and scanning electron microscope techniques. The X-ray diffraction data showed that, with a lower concentration of clay, a highly exfoliated clay structure was achieved whilst the clay aggregation gradually resulted in a higher concentration of clay. The crosslink density as computed based on the solvent absorption data of the latex nanocomposite films was increased with the increase of clay concentration. As a result of nanoscale dispersion of the montmorillonite clay and higher crosslink density of the latex nanocomposite films, the resistance to permeation of small molecules through the NRLCN was significantly enhanced in comparison to conventional NR latex-CaCO 3 composites. Solid state mechanical properties of NRLCNs showed a significant reinforcement effect of dispersed clay platelets but without significantly reducing the elastic properties. The higher mechanical properties and improved barrier resistance indicated that NR latex nanocomposites containing montmorillonite clay is a potential replacement for conventional NR latex composites containing CaCO 3 .

New approach for preparation of dry natural rubber nanocomposites through acid‐free co‐coagulation: Effect of organoclay content

“…However, M L decreases with increase of OMMT‐C loading due to enhancement of plasticizing effect caused by the cationic surfactant, CTAB. Increase of M H and decrease of M L occurred with the addition of OMMT‐C into NR resulting in the increase in M H ‐M L. It was reported that an increase of M H –M L due to increased crosslink density in rubber–nanoclay composites having clay structures with higher inter gallery spaces . Aggregation or de‐intercalation of clay layers at higher OMMT‐C loadings could also influence towards increase in M H –M L, without increase in crosslink density.…”

“…Compared to the Control, an increase of 20% of crosslink density was showed by the vulcanizate at OMMT‐C loading of 2 phr, and is due to formation of more crosslinks in the presence of additional zinc–amine complexes. Higher degree of exfoliation at lower OMMT‐C loadings improves the barrier resistance and reduces the degree of swelling, which causes a higher crosslink density . A blend of exfoliated clay structures and “separated clay structures” in the rubber matrix formed at lower OMMT‐C loadings imparts synergistic contribution to the barrier resistance and may improve the crosslink density .…”

“…Organoclay in solid state can also be incorporated into rubber using conventional dry rubber compounding techniques. However, obtaining uniform clay dispersions in rubber compounds is still a challenge …”

The Influence of Bleached Jute Fiber Filler on the Properties of Vulcanized Natural Rubber

“…The dispersion of the fibers in the composites, however, remains challenging because they tend to agglomerate 5 . For nanoparticle dispersions in natural rubber composites, an effective method for the dispersion of particles in latex has already been demonstrated 1,[18][19][20] . The objective of this work was to incorporate and disperse treated jute fibers in latex and to evaluate the mechanical, dynamic mechanical, and morphological properties of the vulcanized composite materials.…”

Preparation and Properties of Organokaolin Natural Rubber Latex Base Vulcanisate

“…Additionally, incorporation of chemicals (ingredients) in the latex stage, followed by further processing, definitely has the unique advantage of excellent dispersion and less molecular weight reduction [17]. There is however, scant information in literature on the use of organoclays in latex elastomers [8,18,19]. The layered clay usually preferred has been montmorillonites.…”