# CROSSLINKING BY PEROXIDE AND SULPHUR VULCANIZATION: CHEMICAL MECHANISMS AND REACTION KINETIC DETERMINATION - A Comprehensive Numerical Model

### Gabriele Milani, Federico Milani

#### Abstract

The work presents a comprehensive numerical model to optimize mechanical properties of thick rubber vulcanized items, comprising medium and high voltage electric cables and 3D devices. Several vulcanization systems are considered, including peroxides and accelerated sulphur. In the case of peroxides, both a genetic algorithm (GA) with zooming and elitist strategy and an alternating tangent (AT) approach are adopted to determine the optimal final mechanical properties (tensile strength) of 2D and 3D rubber items. The use of a mixture of peroxides is also taken into account, demonstrating that it helps in reducing the curing time and/or in increasing the optimal tensile strength in both core and skin of thick devices. For sulphur vulcanization, a mathematical kinetic model is presented to accurately predict the crosslinking density of vulcanized rubber. It bases on the actual reactions occurring in practice and allows to estimate the overall degree of vulcanization of real manufactured items.

#### References

- ASTM D 2084-81 and ASTM D 5289, Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers.
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- Milani, G., Milani, F., 2008. Genetic algorithm for the optimization of rubber insulated high voltage power cables production lines. Computers & Chemical Engineering, 32: 3198-3212.
- Milani, G., Milani, F., 2009. Optimization of power cable production lines for EPM/EPDM elastomers by Genetic Algorithm with different peroxides. Journal of Applied Polymer Science, 111(1): 482-507.
- Milani, G., Milani, F., 2010b. Optimal vulcanization of 2D-3D EPM/EPDM thick elements through peroxidic mixtures. Journal of Mathematical Chemistry 47(1), pp. 229-267.
- Milani, G., Milani, F., 2010a. A new simple numerical model based on experimental scorch curve data fitting for the interpretation of sulphur vulcanization. Journal of Mathematical Chemistry, 48: 530-557.
- Milani, G., Milani, F., 2011a. A three function numerical model for the prediction of vulcanization-reversion of rubber during sulphur curing. Journal of AppliedPolymer Science, 119(2), pp. 419-437.
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#### Paper Citation

#### in Harvard Style

Milani G. and Milani F. (2011). **CROSSLINKING BY PEROXIDE AND SULPHUR VULCANIZATION: CHEMICAL MECHANISMS AND REACTION KINETIC DETERMINATION - A Comprehensive Numerical Model** . In *Proceedings of 1st International Conference on Simulation and Modeling Methodologies, Technologies and Applications - Volume 1: SIMULTECH,* ISBN 978-989-8425-78-2, pages 87-92. DOI: 10.5220/0003543000870092

#### in Bibtex Style

@conference{simultech11,

author={Gabriele Milani and Federico Milani},

title={CROSSLINKING BY PEROXIDE AND SULPHUR VULCANIZATION: CHEMICAL MECHANISMS AND REACTION KINETIC DETERMINATION - A Comprehensive Numerical Model},

booktitle={Proceedings of 1st International Conference on Simulation and Modeling Methodologies, Technologies and Applications - Volume 1: SIMULTECH,},

year={2011},

pages={87-92},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0003543000870092},

isbn={978-989-8425-78-2},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of 1st International Conference on Simulation and Modeling Methodologies, Technologies and Applications - Volume 1: SIMULTECH,

TI - CROSSLINKING BY PEROXIDE AND SULPHUR VULCANIZATION: CHEMICAL MECHANISMS AND REACTION KINETIC DETERMINATION - A Comprehensive Numerical Model

SN - 978-989-8425-78-2

AU - Milani G.

AU - Milani F.

PY - 2011

SP - 87

EP - 92

DO - 10.5220/0003543000870092