Dynamic mechanical properties of chlorinated butyl rubber blends

Blending of rubber is an important route to modify properties of individual elastomeric components in order to obtain optimum chemical, physical, and mechanical properties. In this study, a novel modification of styrene butadiene rubber (SBR) is made by employing acrylic rubber (ACM) to obtain blends of outstanding mechanical, dynamic, and oil resistance properties. In order to achieve those properties, we used a unique vulcanizing system that improves the crosslink density between both polymers and enhances the dynamic mechanical properties as well as its resistance to both motor and break oils. Static mechanical measurements, tensile strength, elongation at break, and hardness are improved together with dynamic mechanical properties investigated using dynamic mechanical analyses. We also proposed a mechanism for the improvement of crosslink density and consequently oil resistance properties. This opens new opportunities for using SBR/ACM blends in oil sealing applications that requires rigorous mechanical and dynamic mechanical properties.

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Study of Utilization of Ground EVA Waste as Filler in NBR Vulcanizates

Polymers and Polymer Composites ◽

10.1177/096739110201000505 ◽

2002 ◽

Vol 10 (5) ◽

pp. 381-390 ◽

Cited By ~ 1

Author(s):

Viviane Xavier Moreira ◽

Bluma Guenther Soares

Keyword(s):

Mechanical Properties ◽

Ethylene Vinyl Acetate ◽

Dynamic Mechanical Properties ◽

Elongation At Break ◽

Rubber Blends ◽

Dynamic Mechanical ◽

Footwear Industry ◽

Wide Range ◽

Acetate Copolymer ◽

Ethylene Vinyl Acetate Copolymer

Rubber blends containing nitrile rubber (NBR) and ground ethylene-vinyl acetate copolymer waste (EVAW) from the footwear industry have been prepared over a wide range of composition (up to 90 phr of waste component). The ground EVAW had particle size in the range of 100-350 mm and a gel content of 60±5%. The effect of different amounts of EVA waste on the tensile strength, elongation at break, hardness, tear strength and dynamic mechanical properties was studied. EVAW had a good reinforcing effect on the NBR matrix. A combination of optimum tensile properties, resistance to solvent penetration and dynamic mechanical properties, such as storage modulus and loss tangent was achieved by introducing 50 phr of EVAW in the NBR matrix. This composition also presents a more uniform morphology, as indicated by scanning electron microscopy.

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Dynamic Mechanical Properties of a Number of Elastomers and Related Polymers from 4 to 250° K

Rubber Chemistry and Technology ◽

10.5254/1.3542884 ◽

1972 ◽

Vol 45 (4) ◽

pp. 1033-1042

Author(s):

R. J. Morgan ◽

L. E. Nielsen ◽

R. Buchdahl

Keyword(s):

Mechanical Properties ◽

Low Temperature ◽

Bond Angle ◽

Dynamic Mechanical Properties ◽

Molecular Packing ◽

Butyl Rubber ◽

Monomeric Unit ◽

Dynamic Mechanical ◽

Young’S Moduli ◽

Cis And Trans

Abstract Young's modulus and mechanical damping have been measured down to 4° K for cis- and trans-polybutadienes, cis- and trans-polyisoprenes, butyl rubber, and random SBR copolymers. Trans-polybutadiene has two large damping peaks below Tg, trans-polyisoprene one peak, while the cis-polymers and butyl rubber show either no damping peaks or only very small ones below Tg. The low-temperature damping peaks of the trans-polymers might be explained by a type of crankshaft motion and by a special motion of the trans-monomeric unit which involves a simultaneous vibration and bond angle deformation. The high Young's moduli of the polybutadienes compared to the polyisoprenes and the SBR copolymers are explained by the good molecular packing of the polybutadienes.

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