Study on High Damping Rubbers. Part 1. Development of High Damping Rubbers by Structural Modification of Natural Rubber.

Shin-ichi INOUE; Tomonori TSUCHIYA; Yukio ONOUCHI; Hiroshi OKAMOTO

doi:10.2324/gomu.72.612

Cis-trans Isomerization in Polyisoprenes. Part VII. Double Bond Movement During Isomerization of Natural Rubber and Related Olefins

Rubber Chemistry and Technology ◽

10.5254/1.3539106 ◽

1967 ◽

Vol 40 (3) ◽

pp. 921-927

Author(s):

J. I. Cunneen ◽

G. M. C. Higgins ◽

R. A. Wilkes

Keyword(s):

Double Bond ◽

Sulfur Dioxide ◽

Natural Rubber ◽

Structural Modification ◽

Anaerobic Conditions ◽

Aerobic Conditions ◽

Trans Isomerization ◽

Acidic Compounds

Abstract When trans-3-methyl-2-pentene or trans-3-methyl-3-hexene is treated with butadiene sulfone, thiolbenzoic acid, and dibenzoyl disulfide under anaerobic conditions, the olefin undergoes only cis-trans isomerization. However, similar reactions in the presence of oxygen or peroxides also cause changes in the position of the double bond. The latter structural modification is probably caused by acidic compounds formed by oxidation of the isomerization reagents. With natural rubber the nonrubber substances prevent movement of the double bond, and cis-trans isomerization is the sole change, even when the reaction with sulfur dioxide is carried out under aerobic conditions.

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Solid State Carbon-13 NMR Studies of Vulcanized Elastomers. III, Accelerated Sulfur Vulcanization of Natural Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3536130 ◽

1987 ◽

Vol 60 (2) ◽

pp. 278-297 ◽

Cited By ~ 21

Author(s):

A. M. Zaper ◽

J. L. Koenig

Keyword(s):

Solid State ◽

Natural Rubber ◽

Nmr Spectra ◽

Structural Modification ◽

Main Chain ◽

Nmr Studies ◽

Structural Modifications ◽

Sulfur Vulcanization ◽

Chain Isomerization ◽

Cyclic Sulfide

Abstract In summary, the solid state C-13 NMR technique has proven to be a significant method for the detection of crosslinks and other structural modifications in accelerated sulfur-vulcanized NR systems. When the amount of accelerator is high in proportion to the amount of sulfur used, the network structure appears to be simpler with less crosslinking, less main chain structural modification, and fewer cyclic sulfide structures as observed in the C-13 NMR spectra. Polysulfidic crosslinks have been detected in addition to polysulfides terminated by accelerator residues. Cis-to-trans chain isomerization is also evident in these vulcanizates.

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Study on High Damping Rubbers. Part 2. Development of High Damping Rubbers by Structural Modification of Natural Rubber.

NIPPON GOMU KYOKAISHI ◽

10.2324/gomu.74.100 ◽

2001 ◽

Vol 74 (3) ◽

pp. 100-104

Author(s):

Shin-ichi INOUE ◽

Satoshi NAKAKITA ◽

Hiroshi OKAMOTO

Keyword(s):

Natural Rubber ◽

Structural Modification

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Effect of Monomers in the Structural Modification of Natural Rubber During Grafting with γ‐Ray Irradiation

Journal of Macromolecular Science Part B ◽

10.1081/mb-120029770 ◽

2004 ◽

Vol 43 (2) ◽

pp. 297-307

Author(s):

Md. Forhad Mina ◽

Tsutomu Asano ◽

Nirmal Chandra Dafader ◽

Feroza Akhtar ◽

Shinya Yoshida ◽

...

Keyword(s):

Natural Rubber ◽

Structural Modification ◽

Γ Ray

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Cristal-growth dynamics of n-doped gaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132352 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1544-1545

Author(s):

Pham V. Huong ◽

Stéphanie Bouchet ◽

Jean-Claude Launay

Keyword(s):

Crystal Growth ◽

Spatial Resolution ◽

Epitaxial Layer ◽

Outer Surface ◽

Gaas Substrate ◽

Structural Modification ◽

Growth Dynamics ◽

Argon Laser ◽

High Anisotropy ◽

Crystal Gaas

Microstructure of epitaxial layers of doped GaAs and its crystal growth dynamics on single crystal GaAs substrate were studied by Raman microspectroscopy with a Dilor OMARS instrument equipped with a 1024 photodiode multichannel detector and a ion-argon laser Spectra-Physics emitting at 514.5 nm.The spatial resolution of this technique, less than 1 μm2, allows the recording of Raman spectra at several spots in function of thickness, from the substrate to the outer deposit, including areas around the interface (Fig.l).The high anisotropy of the LO and TO Raman bands is indicative of the orientation of the epitaxial layer as well as of the structural modification in the deposit and in the substrate at the interface.With Sn doped, the epitaxial layer also presents plasmon in Raman scattering. This fact is already very well known, but we additionally observed that its frequency increases with the thickness of the deposit. For a sample with electron density 1020 cm-3, the plasmon L+ appears at 930 and 790 cm-1 near the outer surface.

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Extraction and identification of fillers and pigments from pyrolyzed rubber and tire samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163332 ◽

1996 ◽

Vol 54 ◽

pp. 174-175

Author(s):

P. Sadhukhan ◽

J. B. Zimmerman

Keyword(s):

Zinc Oxide ◽

Electron Microscope ◽

Carbon Black ◽

Natural Rubber ◽

Transmission Electron Microscope ◽

Rolling Resistance ◽

Synthetic Polymers ◽

Nitrogen Atmosphere ◽

Transmission Electron ◽

Curing Agents

Rubber stocks, specially tires, are composed of natural rubber and synthetic polymers and also of several compounding ingredients, such as carbon black, silica, zinc oxide etc. These are generally mixed and vulcanized with additional curing agents, mainly organic in nature, to achieve certain “designing properties” including wear, traction, rolling resistance and handling of tires. Considerable importance is, therefore, attached both by the manufacturers and their competitors to be able to extract, identify and characterize various types of fillers and pigments. Several analytical procedures have been in use to extract, preferentially, these fillers and pigments and subsequently identify and characterize them under a transmission electron microscope.Rubber stocks and tire sections are subjected to heat under nitrogen atmosphere to 550°C for one hour and then cooled under nitrogen to remove polymers, leaving behind carbon black, silica and zinc oxide and 650°C to eliminate carbon blacks, leaving only silica and zinc oxide.

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