In this work, a new analytical methodology is proposed to separate squalene from its by-products after vulcanization, using reverse phase liquid chromatography. Regarding previous methods described in literature, the separation between reaction products and their detection have been clearly improved. A light scattering detector has been coupled to the HPLC equipment substituting the traditional...

Two silane coupling agents were used for hydrolysis-condensation reaction modification of nanosilica surfaces. The surface characteristics were analyzed using Fourier transform infrared spectroscopy (FTIR). The vulcanization kinetics of natural rubber (NR) + silica composites was studied and compared to behavior of the neat NR using differential scanning calorimetry (DSC) in the dynamic scan mo...

The optimal process conditions for a high ratio of de-vulcanization to polymer degradation have been elaborated for tire rubbers: SBR, BR, NR and CIIR. These polymers all show their own particular breakdown characteristics, and the temperature dependence of the breakdown mechanism was investigated by measuring sol fractions and crosslink densities. For SBR and BR, the highest reduction in cross...

The Essay starts with an overview of the percolation approach and classical elasticity theory of the vulcanization transition of rubber, describing their assumptions and their limitations. Thereafter we discuss a third approach, the Vulcanization Theory (VT) which incorporates the effects of thermal fluctuations and quenched random disorder. The VT is an order parameter theory in the true Landa...

In this research sodium bicarbonate (NaHCO3) was introduced to generate carbon dioxide gas (CO2) to the existing nitrogen gas (N2) of elastomeric foam, to lower thermal conductivity (K). Various loadings of NaHCO3 (0 to 60 phr) were added into the azodicarbonamide (AZC)-containing compound and its properties were then determined. Two vulcanization methods, i.e., hot air and infrared (IR), were ...

2014 We consider a polymer melt, with polymerization index N and a fraction p of cross linked monomers, for values of p close to the gelation threshold (p = 03C1c + 039403C1). Using a Ginsburg argument, we find that (in three dimensions) the Flory theory is qualitatively correct whenever N > (03C1c/039403C1)3. For shorter chains the critical exponents are expected to be of the percolation ...