Cross-linking Process, Mechanical Properties and EMI Absorption Shielding Efficiency of Composites Based on NBR | Chapter 2 | Current Approaches in Engineering Research and Technology Vol. 8

The rapid progress in industrialization and informatization of modern society has led to the generation of high amounts of environmental pollution, especially from electromagnetic radiation. Electromagnetic interference can be explained as the undesired disturbances in electronic appliances, which are caused by interference of multiple electromagnetic signals transmitting from neighboring devices. Acrylonitrile-butadiene rubber (NBR) is one of the most widely used specialty type rubber with a good correlation between cost and properties. Due to its polar character, it has good resistance to oils and non-polar solvents. Two types of composites were tested for electromagnetic interference absorption shielding performance, cross-linking process and physical-mechanical properties. Manganese-zinc ferrite, nickel-zinc ferrite, and both fillers in their mutual combinations were incorporated into acrylonitrile-butadiene rubber. The overall content of the filler, or fillers combinations was kept at 200 phr. Carbon black, or carbon fibres, respectively were incorporated into each rubber formulation in constant loading - 25 phr. The work was focused on the understanding of correlation between electromagnetic shielding parameters and electrical conductivity of composites in relation to their absorption shielding effectiveness. The absorption shielding ability of materials was evaluated within the frequency range from 1 MHz to 6 GHz. The study revealed a good correlation among permittivity, conductivity, and EMI absorption shielding. The higher the conductivity, the higher the permittivity, resulting in the lower absorption shielding performance. The higher the ratio of nickel-zinc ferrite in magnetic filler combinations, the lower the conductivity and permittivity and the higher the absorption shielding. The experimentally obtained data also revealed that the influence of the type of ferrite or ferrites combinations on curing parameters and physical-mechanical properties was negligible.

 

 

Author (s) Details

Ján Kruželák
Department of Plastics, Rubber and Fibres, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, 812 37 Bratislava, Slovakia.

 

Andrea Kvasnicakova
Department of Plastics, Rubber and Fibres, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, 812 37 Bratislava, Slovakia.

 

Michaela Džuganová
Department of Plastics, Rubber and Fibres, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, 812 37 Bratislava, Slovakia.

 

Rastislav Dosoudil
Department of Electromagnetic Theory, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology in Bratislava, Ilkovicova 3, 812 19, Bratislava, Slovakia.

 

Ivan Hudec
Department of Plastics, Rubber and Fibres, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, 812 37 Bratislava, Slovakia.

 

Please see the book here:- https://doi.org/10.9734/bpi/caert/v8/1885

 

Shifting Properties of Silica Reinforced Natural Rubber Based Truck Tire Tread Compounds by Small Amounts of Hybrid Fillers towards Better Overall Performance | Chapter 7 | Current Innovations in Chemical and Materials Sciences Vol. 5

Modern high-performance tire treads are presently commonly reinforced with silica as rubber fillers because they raise key tire performance criteria such as lower rolling resistance and higher wet grip compared to carbon black-filled rubber. The present work aims at a synergistic effect of silica with different additional fillers in order to shift tire performance with respect to wet grip and rolling resistance for safety and fuel savings, respectively towards a better abrasion resistance, all characterized by the dynamic mechanical properties of the vulcanized compounds. The use of small amounts of secondary fillers or hybrid fillers in silica-reinforced tire tread compounds has the potential to improve tire performance further. In the present work, two secondary fillers: organoclay nanofiller and N134 carbon black were added to silica-based natural rubber compounds at a proportion of silica/secondary filler of 45/10 phr. The compounds were prepared with variable mixing temperatures based on the procedure commonly used for silica-filled NR systems. The results of Mooney viscosity, Payne effect, cure behavior and mechanical properties imply that the silica hydrophobation and coupling reaction of the silane coupling agent between the silica and elastomer are significantly enhanced by organoclay due to an effect of its modifier: an organic ammonium derivative. This modifier has an effect on scorch safety and cure rate. The compounds where carbon black was added as a secondary filler do not show this improvement. They give inferior filler dispersion compared to the pure silica-filled compound, attributed to an inappropriate high mixing temperature and the large specific surface area of the carbon black used. The dynamic mechanical properties indicate that organoclay as a secondary filler has the potential to improve the wet traction and rolling resistance of a tire tread, while the use of carbon black in silica-filled NR does not change these properties.

Author(s) Details:

S. Sattayanurak,
Sustainable Elastomer Systems, Department of Mechanics of Solids, Surfaces & Systems, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands and Department of Rubber Technology and Polymer Science, Faculty of Science and Technology, Prince of Songkla University, Pattani Campus, Thailand and Department of Rubber and Polymer Engineering, Faculty of Engineering, Thaksin University, Phatthalung Campus, Thailand.

J. W. M. Noordermeer,
Noordermeer Rubber Consultancy, Nieuwstadt, The Netherlands.

K. Sahakaro,
Sustainable Elastomer Systems, Department of Mechanics of Solids, Surfaces & Systems, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands and Department of Rubber Technology and Polymer Science, Faculty of Science and Technology, Prince of Songkla University, Pattani Campus, Thailand.

W. Kaewsakul,
Sustainable Elastomer Systems, Department of Mechanics of Solids, Surfaces & Systems, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands.

A. Blume,
Sustainable Elastomer Systems, Department of Mechanics of Solids, Surfaces & Systems, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands.

W. K. Dierkes,
Sustainable Elastomer Systems, Department of Mechanics of Solids, Surfaces & Systems, Faculty of Engineering Technology, University of Twente, Enschede, The Netherlands.

Please see the link here: https://stm.bookpi.org/CICMS-V5/article/view/13187