Measuring effect of the blooming of chemical curatives on the rate of cyclic fatigue crack growth in natural rubber filled with a silanized silica nanofiller
journal contributionposted on 2017-09-15, 09:59 authored by Farhan Saeed, Ali Ansarifar, Robert J. Ellis, Yared Haile-Meskel
Two rubber compounds with different amounts of chemical curatives were prepared by mixing natural rubber with a high loading of a sulfur-bearing silanized precipitated amorphous white silica nanofiller. The chemical bonding between the filler and rubber was optimized via the tetrasulfane groups of the silane by adding a sulfenamide accelerator and zinc oxide. The rubber compounds were cured and stored at ambient temperature for 65 days before they were tested. One compound showed extensive blooming as a function of storage time. Thin tensile strips of the rubber vulcanizates containing an edge crack were repeatedly stressed at constant strain amplitude and test frequency at ambient temperature and crack length c was measured as a function of the number of cycles n. The cut growth per cycle, dc/dn, was calculated and plotted against the tearing energy, T. The blooming of the chemical curatives increased dc/dn by up to an order of magnitude at a constant T. This was due to the reagglomeration of the chemical curatives in the rubber and also within a thin layer approximately 15 to μm in size beneath the rubber surface. Under repeated stressing, cracks grew through the relatively weak agglomerated areas in the rubber and this caused the rate of crack growth to increase at a constant T.
- Aeronautical, Automotive, Chemical and Materials Engineering
Published inJournal of Applied Polymer Science
Pages1372 - 1383
CitationSAEED, F. ... et al., 2012. Measuring effect of the blooming of chemical curatives on the rate of cyclic fatigue crack growth in natural rubber filled with a silanized silica nanofiller. Journal of Applied Polymer Science, 124 (2), pp.1372-1383.
Publisher© John Wiley and Sons
- AM (Accepted Manuscript)
Publisher statementThis work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
NotesThis is the peer reviewed version of the following article: SAEED, F. ... et al., 2012. Measuring effect of the blooming of chemical curatives on the rate of cyclic fatigue crack growth in natural rubber filled with a silanized silica nanofiller. Journal of Applied Polymer Science, 124 (2), pp.1372-1383, which has been published in final form at: http://dx.doi.org/10.1002/app.34913. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.