Evaluation of New Thermal Stabilizers and Antifatigue Agents for Rubber Vulcanizates

Abstract

Seven organo-phosphorus compounds were synthesized and incorporated in natural rubber (NR) and styrene-butadiene rubber (SBR) mixes. The rheometric characteristics of the green rubber mixes were determined using the oscillating disc rheometer. The prepared compounds were evaluated as thermal stabilizers and antifatigue agents in NR and SBR vulcanizates. The results revealed that the prepared compounds were good antioxidants and antifatigue agents for rubber vulcanizates exceeding the commercial antioxidant 4-methyl-2,6-di-tert-butyl phenol, which is used in the rubber industry. In addition, the efficiency of such compounds depends on their chemical structure.

Keywords:

• Organo-phosphorus compounds
• Thermal stabilizer
• Antifatigue agents
• NR vulcanizates
• SBR vulcanizates

ACKNOWLEDGMENTS

The authors are grateful to SABIC, Saudi Basic Industries Corporation, for the financial support through thier Institute of Research & Consultation, King AbdulAziz University under grant number MS-7-47.

Notes

Where Phr: part per hundred parts of rubber; ML: minimum torque; MH: maximum torque; tc₉₀: optimum cure time; ts₂: scorch time; CRI: cure rate index; T.S: tensile strength; E: elongation at break; Q: equilibrium swelling.