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Thermal Aging Properties of NR Vulcanizates with Different Cure Systems  

Choi, Sung-Seen (Department of Applied Chemistry, Sejong University)
Park, Byung-Ho (Kumho Research and Development Center)
Publication Information
Elastomers and Composites / v.40, no.3, 2005 , pp. 181-187 More about this Journal
Abstract
Changes of physical properties or NR vulcanizates with different cure systems by thermal aging were investigated. Two sulfur cure systems and one resole cure system were employed, and total contents of the curatives were varied. For the NR vulcanizates with sulfur cure systems, hardness and modulus after the thermal aging at $90^{\circ}C$ for 3 days were increased, but elongation at break and tensile strength were decreased. For the NR vulcanizates with resloe cure system, the physical properties after the thermal aging were decreased. The change of physical properties by the thermal aging was explained with the crosslink density change. The crosslink densities or the NR vulcanizates with sulfur cure systems were increased after the thermal aging, but those with resole cure system were decreased. Influence of the migration of antidegradant on the changes of physical properties was also investigated. However, the changes of physical properties by the thermal aging were not explained sufficiently with the migration of antigradant.
Keywords
thermal aging; NR vulcanizate; crosslink density; migration of antidegradant; physical property;
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1 N. J. Morrison and M. Porter, 'Temperature effects on the stability of intermediates and crosslinks in sulfur vulcanization', Rubber Chem. Technol., 57, 63 (1984)
2 M. R. Krejsa and J. L. Koenig, 'Review of sulfur crosslinking fundamentals for accelerated and unaccelerated vulcanization', Rubber Chem. Technol., 66, 376 (1993)
3 E. Morita, 'Correlation analysis of curing agents', Rubber Chem. Technol., 57, 744 (1984)
4 M. S. Feldshtein, I. G. Chemomorskaya, E. N. Guryanova, and I. I. Eitingon, 'Accelerator activity of 2-benzothiazole sulfenamide additives and the exchange of benzyl thiyl radicals with radioactive 2-benzthiazyl disulfide', Rubber Chem. Technol., 35, 562 (1962)
5 S.-S. Choi, 'Bond dissociation of sulfur crosslinks in IR and BR vulcanizates using semi-empirical calculations', Kor. Polym. J, 5, 39 (1997)
6 S.-S. Choi, 'Resole-cured NR vulcanizates with thermally reacted p-t-octylphenol formaldehyde resole', J. Appl. Polym. Sci., 68, 1811 (1998)   DOI   ScienceOn
7 S.-S. Choi, 'Influence of thermally aged resoles on properties of resole-cured butyl rubber vulcanizates', Kor. Polym. J., 7, 30 (1999)
8 S.-S. Choi, B.-H. Park, S. G. Lee, and B. T. Kim, 'Binary cure systems of 1,6-bis(N,N-diben zylthiocarbamoyldithio )-hexane and benzothiazole sulfenamides in carbon black-filled natural rubber compounds', Bull. Kor. Chem. Soc., 23, 320 (2002)
9 S.-S. Choi, 'Structural characteristics of p-t- octylphenol formaldehyde resole resins using molecular simulation', Polym. Adv. Technol., 13, 94 (2002)   DOI   ScienceOn
10 S.-H. Chough and D.-H. Chang, 'Kinetics of sulfur vulcanization of NR, BR, SBR, and their blends using a rheometer and DSC', J. Appl. Polym. Sci., 61, 449 (1996)
11 S.-S. Choi, 'Influence of rubber composition on change of crosslink density of rubber vulcanizates with EV cure system by thermal aging', J. Appl. Polym. Sci., 75, 1378 (2000)   DOI   ScienceOn
12 D. S. Campbell, 'Structural characterization of vulcanizates 12. Efficient vulcanization using a sulfenamide-thiuram disulfide accelerator system', Rubber Chem. Technol., 45, 1366 (1972)
13 S.-S. Choi, 'Cure characteristics of carbon blackfilled rubber compounds composed of NR, SBR, and BR', Elastomer, 35, 215 (2000)
14 C. R. Parks and R J. Brown, 'Crosslink density of elastomers. A new gas-chromatographic method' Rubber Chem. Technol., 49, 233 (1976)
15 R. W. Layer, 'Recuring vulcanizates. I. A novel way to study the mechanism of vulcanization', Rubber Chem. Technol., 65, 211 (1992)
16 S. K. Chakraborty, A. K. Bhowmick, and S. K. De, 'Mixed crosslink systems in elastomers', J. Macromol. Sci.-Rev. Macromol. Chem., C21, 313 (1981-82)
17 M. van Duin and A. Souphanthong, 'The chemistry of phenol formaldehyde resin vulcanization of EPDM: Part I. Evidence for methylene crosslinks', Rubber Chem. Technol., 68, 717 (1995)
18 S.-S. Choi, 'Influence of thermal aging on change of crosslink density and deformation of natural rubber vulcanizates', Bull. Kor. Chem. Soc., 21, 628 (2000)
19 R. N. Datta, 'Dual function curative for NR', J. Appl. Polym. Sci., 37, 443 (1989)
20 C. H. Chen, J. L. Koenig, J. R. Shelton, and E. A. Collins, 'Characterization of the reversion process in accelerated sulfur curing of natural rubber', Rubber Chem. Technol., 54, 734 (1981)   DOI   ScienceOn
21 C. J. Hann, A. B. Sullivan, B. C. Host, and G. H. Kuhls, Jr., $^{11}Vulcanization$ chemistry, comparison of the new accelerator N-t-butyl-2-benzothiazole sulfenimide (TBSI) with N-t-butyl-2-benzothiazole sulfenamide (TBBS)', Rubber Chem. Technol., 67, 76 (1994)   DOI   ScienceOn