Dominant formation of disulfidic linkages in the sulfur cross-linking reaction of isoprene rubber by using zinc stearate as an activator

Abstract

The bridging bidentate zinc/stearate complex, an intermediate for the sulfur cross-linking reaction, supposedly induces an abundance of disulfidic linkages in the rubber network.

Necessity of two-dimensional visualization of validity in the nanomechanical mapping of atomic force microscopy for sulphur cross-linked rubber

“…The 2D mapping image of the reliability index in the AFM nanomechanical mapping is demonstrated for a sulphur crosslinked rubber and its importance is emphasized for the rst time as far as we have concerned. The quantitative and reliable Young's modulus map will become an evidence to correctly support a new concept for the vulcanization mechanism which we found in the studies by small-angle neutron scattering (SANS) 28 and synchrotron X-ray absorption ne structure (XAFS) [29][30][31][32] The novel mechanism was expected to be a key to develop rubber science and technology as described in the ACS News Service Weekly PressPac in 2015. 33…”

Effect of fatty acids on the accelerated sulfur vulcanization of rubber by active zinc/carboxylate complexes

“…15 Without StH, the average Young's modulus of mesh network in the matrix of the sulfur cross-linked isoprene rubber was found to be very low, possibly attributed to the lack of intermediate of zinc/stearate complex inducing the mesh network formation. Furthermore, using a linear combination tting in sulfur K-edge X-ray absorption near edge structure measurements for the solvent extracted sulfur cross-linked isoprene rubber, the suldic linkage of a disuldic type was found to be dominant in the CBS-accelerated system when either zinc stearate 16 or a combination of ZnO and StH 17 were used as the activators. Importantly, the presence of the bridging bidentate zinc/stearate complex as an intermediate for the sulfur cross-linking reaction was suggested to induce the generation of abundant disuldic linkages in the rubber networks.…”

In situ generation of sulfur using silica as a carrier in the wet mixing of natural rubber latex

“…T 2 is the relaxation time, and a smaller T 2 indicates a smaller degree of freedom of the rubber molecular chain is. M c is the average relative molecular mass between two adjacent cross‐linking points 19–21 . It can be seen from Table 3 that M C and T 2 of in situ S‐Silica/NR composite are smaller because upon increasing the cross‐linking density, the movement of the rubber chains becomes more restricted, and the internal network structure of rubber becomes more compact and stable; thus, the distance between two adjacent cross‐linking points decreases, so M c decreases.…”