Ethylene–propylene–diene terpolymer/silica compound modification with organosilane [bis(triethoxysilylpropyl)disulfide] and improved processability and mechanical properties

Abstract

Bifunctional silane [bis(triethoxysilylpropyl)-disulfide (TESPD)] was added to a silica-containing ethylene-propylene-diene terpolymer mold compound, and its effects with respect to the vulcanization properties, processability, and physical properties were investigated. The addition of TESPD caused reduced heat generation during mixing, low minimum torque, low drop temperature, and low extrusion pressure buildup in the extruder. It also caused a high vulcanization torque, high torque rise, high torque maximum, and high elongational modulus.

Developing ethylene-propylene-diene rubber compounds for industrial applications using a sulfur-bearing silanized silica nanofiller

“…Compounds 1 and 4; Table ). It is interesting that a similar behavior was also reported by Kim who showed major improvement in the mechanical properties of an EPDM rubber after adding precipitated silica and a sulfur‐bearing liquid silane similar to TESPT.…”

“…The bound rubber content also increased as a function of the silica loading though the increase was more significant when TESPT was present in the rubber. A similar study by Kim reported significant increases in the cross‐link density of an EPDM rubber when a bifunctional silane was added. The silane‐added compound showed a higher elongational modulus than the control one.…”

“…There is also a major concern about the cure systems in these compounds. For instance, in some EPDM vulcanizates where liquid TESPT and precipitated silica were used , the cure system consisted of 5 phr ZnO and 1 phr stearic acid (primary and secondary activators), 3.1 phr accelerators (primary and secondary), and 0.8 phr curing agents (sulfur substitute), adding up to 9.9 phr, which was too much. As this study has shown that the problems mentioned earlier were remedied when TESPT pretreated silanized silica was used and the chemical bonding between the rubber and filler was optimized via the tetrasulfane groups of TESPT by using TBBS and ZnO.…”

“…There are a number of fillers which can replace CB in EPDM because of their ability to improve the rubber properties. The most widely researched alternative fillers to CB are organoclays , synthetic silicas , white rice husk ash , kaolin , and quartz . However, silicas with surface areas ranging from 125 to 200 m 2 g −1 have shown to be very effective in improving the mechanical properties of rubber vulcanizates and have gained considerable importance in recent years .…”

Studies on Thermal and Morphological Behavior of 3- Aminopropyltriethoxysilane Grafted Epoxidized EthylenePropylene-Diene Terpolymer

“…Oxiranes are generally prepared using perbenzoic acid (9), chloroperbenzoic acid (10) and monoperphthalic acid (11). Performic acid is an extremely active organic peracid (12)(13)(14)(15)(16) used for the epoxidation, but, owing to its instability (17), it has to be prepared in situ.…”