Some New Aspects of Ozone and Its Reactions with Diene Rubbers

2013 ◽  
pp. 1-29
Author(s):  
G Zaikov ◽  
S Rakovsky ◽  
M Anachkov ◽  
E Pearce ◽  
G Kirshenbaum
Keyword(s):  
Diene Rubbers

Network evolution based on general-purpose diene rubbers/sulfur/TBBS system during vulcanization (I)

Polymer ◽  
2010 ◽  
Vol 51 (1) ◽  
pp. 257-263 ◽  
Author(s):  
Ping Zhang ◽  
Fei Zhao ◽  
Yuan Yuan ◽  
Xinyan Shi ◽  
Shugao Zhao
Keyword(s):  
General Purpose ◽  
Network Evolution ◽  
Diene Rubbers

IR spectroscopic study of the molecular structure of highly filled systems of low molecular diene rubbers

1978 ◽  
Vol 20 (5) ◽  
pp. 1269-1275
Author(s):  
N.V. Ionina ◽  
Ye.Ye. Avstriiskaya ◽  
A.P. Berezkina ◽  
K.V. Nel'son
Keyword(s):  
Molecular Structure ◽  
Spectroscopic Study ◽  
Diene Rubbers ◽  
Ir Spectroscopic

Halogenation of Ethylene Propylene Diene Rubbers

1971 ◽  
Vol 44 (4) ◽  
pp. 1025-1042 ◽  
Author(s):  
R. T. Morrissey
Keyword(s):  
Natural Rubber ◽  
Double Bonds ◽  
Optimum Amount ◽  
Ethylene Propylene ◽  
Rubber Compounds ◽  
Rubber Part ◽  
Curing Agents ◽  
Diene Rubbers ◽  
Curing Systems

Abstract The ethylene propylene diene rubbers (EPDM) have been modified by halogenation. The reaction has been considered as one mainly of addition to the double bonds of the diene portion of the rubber. Dehydrohalogenation may occur to varying degrees, depending on the conditions of the reaction and the diene present in the rubber. Part of the halogen is believed to be in the allylic position. The halogenated EPDM may be vulcanized by sulfur as well as many of the curing agents used for other halogen-containing polymers. Both types of curing systems can function in the same compound. Therefore, the halogenated EPDM rubbers can be covulcanized with the highly unsaturated elastomers such as natural rubber, cis polybutadiene, and the SBR rubbers. The excellent properties, resistance to ozone, and flexing, of the halogenated EPDM can be imparted to these elastomers using standard curing systems. Also, the uncured tack of halogenated EPDM can be improved by increasing amounts of natural rubber. In addition, other advantages are adhesion of these blends to other rubber compounds and metal. It has been shown that the cure compatibility properties of the halogenated EPDM can be varied as the halogen is increased in the rubber. Evidence has been presented which shows there is an optimum amount of halogen necessary for the best properties in mixtures with other elastomers.

Ketonization of a nitrile-butadiene rubber by nitrous oxide: Comparison with the ketonization of other type diene rubbers

2009 ◽  
Vol 45 (12) ◽  
pp. 3355-3362 ◽  
Author(s):  
Sergey V. Semikolenov ◽  
Konstantin A. Dubkov ◽  
Dmitry P. Ivanov ◽  
Dmitry E. Babushkin ◽  
Mikhail A. Matsko ◽  
...  
Keyword(s):  
Nitrous Oxide ◽  
Butadiene Rubber ◽  
Nitrile Butadiene Rubber ◽  
Diene Rubbers

Tensile Stress—Strain Measurements for Characterization of Gum Elastomers and Filled Compounds

1990 ◽  
Vol 63 (4) ◽  
pp. 624-636 ◽  
Author(s):  
N. Nakajima ◽  
M. H. Chu ◽  
R. Babrowicz
Keyword(s):  
Shear Modulus ◽  
Tensile Stress ◽  
Shear Deformation ◽  
Tensile Modulus ◽  
Nonlinear Behavior ◽  
Material Behavior ◽  
Structural Constraints ◽  
Stress Strain ◽  
Strain Measurements ◽  
Diene Rubbers

Abstract For a gum elastomer in its amorphous, isotropic state, shear modulus and tensile modulus are related with a factor of three. This relation is maintained in the range of temperature and time scale defining the rubbery region of the material behavior. When a large deformation is imposed, for example, in tensile stress—strain measurements, the above relation may still be preserved, if the nonlinear behavior can be linearized. The strain—time correspondence principle is the linearization scheme of this work. When a gum elastomer contains various structural constraints, the factor three relation does not apply, even after the application of the above linearization scheme. Example of constraints are excessive amounts of long branches, gel, molecular associations, and reinforcing fillers. These constraints usually make the factor larger than three. This is because the constraints make the large, elongational deformation more difficult to achieve compared to shear deformation. An example of gum elastomer in this work is a polyethylacrylate containing a significant amount of gel. With this polymer, both the presence of gel and the molecular association act as the constraints. However, when 50 phr of carbon blacks are added, the fillers do not act as strong constraints as they do when they are in the diene rubbers. This is because the polyethylacrylate is known to have a weaker affinity to carbon black compared to the diene rubbers. Triblock copolymers, styrene—isoprene—styrene, were examined according to the above treatment; 25% polystyrene copolymer exhibited crosslink-like behavior by the polystyrene domains. However, 14% polystyrene copolymers acted as if they are no crosslinks. When these copolymers are diluted to 44% with an addition of 56% tackifier, the ratio of tensile to shear modulus became less than three. The styrene domains must have effective crosslinks at the small shear deformation, but at large tensile deformations such crosslinks must not be present.

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