Rubber Gives Thermal Insulation

Carbon black represents the most commonly employed elemental pigment used in PVC and perhaps the entire plastics and rubber industry. While more ofien employed as a reinforcement in elastomers, carbon blacks of a wide variety and source are excellent colorants for PVC. Three main classifications of carbon black are channel blacks, furnace blacks and thermal blacks (21). Channel blacks give very good UV stability (63,64), furnace blacks are recommended for electrical insulation (65), and thermal blacks are lowest in cost... 

The improvement in thermal stability of the nanocomposites compared to the neat EVA/natural rubber is due to the barrier effect and insulating properties of organoclay. The well dispersed plate-like silicate layers form a tortuous path in the polymer matrix which gives a barrier effect and inhibits the diffusion of volatile degradation product from the inside of the polymer matrix. Moreover the well-dispersed silicate layers restrict the movement of polymeric chains, hence reducing the free volume for diffusion of volatile degradation products. Other researchers also confirm that organoclay tends to form a compact char-like residue on the surface of the nanocomposites when it is burnt. This char-like structure is incombustible and acts as an insulator which inhibits heat transfer to the inside of the nanocomposites. At 8 phr... 

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