Rubber blend composites

Presents current research activities on new rubbers, thermoplastic elastomers, nanocomposites, biomaterials, and smart polymers, as well as rubber blends, composites, and rubber ingredients... 

Chlorobutyl Rubber and Bromobutyl Rubbers (CIIR and BUR). The addition of chlorine or bromine to HR in an inert solvent (e.g., hexane) gives the facile attachment of one halogen atom per isoprene unit in the allylic position. Compared with HR, the halogenated butyl rubbers have certain advantages. The cure reactivity is increased to give faster vulcanization rates, greater extents of vulcanization, and reduced reversion. Also, the halo-genation improves the compatibility of the isoprene polymer with other types of rubber (e.g., NR) to make useful rubber-blend compositions possible. 

Non-linear Viscoelastic Behaviour of Rubber-Rubber Blend Composites and Nanocomposites Effect of Spherical, Layered and Tubular Fillers... 

Abstract This chapter deals with the non-linear viscoelastic behaviour of rubber-rubber blend composites and nanocomposites with fillers of different particle size. The dynamic viscoelastic behaviour of the composites has been discussed with reference to the filler geometry, distribution, size and loading. The filler characteristics such as particle size, geometry, specific surface area and the surface structural features are found to be the key parameters influencing the Payne effect. Non-Unear decrease of storage modulus with increasing strain has been observed for the unfilled vulcanizates. The addition of spherical or near-spherical filler particles always increase the level of both the linear and the non-linear viscoelastic properties. However, the addition of high-aspect-ratio, fiber-like fillers increase the elasticity as well as the viscosity. 

Non-linear Viscoelastic Behaviour of Rubber-Rubber Blend Composites and. 

The properties of rubber-rubber blend composites depend on the size and shape and concentration of nano particles and their interactions with the individual mbber matrix. The interaction between the filler and the matrix are improved by surface modification. In the mbber industry the uniform distribution of nano particles is considered to be important as it affects the mechanical properties and performance of the composite. For mbber-mbber blend composites fillers like carbon black prefer to migrate to less polar, less viscous mbber phase whereas silica and clay particles migrate to more polar mbber phase. CNTs mainly reside in the highly polar and non-polar mbbers but not in weakly polar ones. The Tg remain unaltered for a completely incompatible blend. In the case of partially compatible blends, the Tgs of the blend components are expected to shift towards each other as compared with the pure components. Shifting of Tg of polymers to lower or higher values in a blend depends on the polarity difference and the difference in the thermal expansion coefficient of the respective polymers in the blend. 

Das, A., Mahaling, R.N., Stdckelhuber, K.W., and Heinrich, G. (2011) Reinforcement and migration of nanoclay in polychloroprene/elhylene—propylene— diene-monomer rubber blends. Composites Science and Teclmology, 71 (3), 276, 7. 

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