Polímeros: Ciência e Tecnologia
Polímeros: Ciência e Tecnologia
Original Article

Tensile and structural properties of natural rubber vulcanizates with different mastication times

Nabil Hayeemasae; Siriwat Soontaranon; Mohamad Syahmie Mohamad Rasidi; Abdulhakim Masa

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Mastication reduced the molecular weight of natural rubber (NR). This would affect the tensile properties and strain-induced crystallization of the rubber vulcanizates due to the structural changes of the rubber molecules. In this study, influences of mastication time on tensile response, deformation-induced crystallization, and structural effects of crosslinked NR were investigated. The crystallization behavior and structural changes during stretching were studied by means of wide angle X-ray scattering (WAXS) and small angle X-ray scattering (SAXS). Increased mastication time significantly affected modulus at specified strain and upturn point of strain-induced crystallization of the crosslinked samples while the tensile strength was influenced slightly by mastication. During stretching, degree of crystallinity at given strain was found to decrease with increasing mastication time, while the crystallite size was reduced. Moreover, the size of crosslinked network structures induced by crosslinking also decreased slightly with increasing mastication time, as suggested by SAXS measurement.



mastication, natural rubber, strain-induced crystallization, tensile properties


1 Smitthipong, W., Suethao, S., Shah, D., & Vollrath, F. (2016). Interesting green elastomeric composites: silk textile reinforced natural rubber. Polymer Testing, 55, 17-24. http://dx.doi.org/10.1016/j.polymertesting.2016.08.007.

2 Noordermeer, J. W. M. (1998). Recent developments in rubber processing leading to new applications such as the “Green Tire”. Macromolecular Symposia, 127(1), 131-139. http://dx.doi.org/10.1002/masy.19981270118.

3 Fries, H., & Pandit, R. R. (1982). Mastication of rubber. Rubber Chemistry and Technology, 55(2), 309-327. http://dx.doi.org/10.5254/1.3535880.

4 Flory, P. J. (1946). Effects of molecular structure on physical properties of butyl rubber. Industrial & Engineering Chemistry, 38(4), 417-436. http://dx.doi.org/10.1021/ie50436a023.

5 Kok, C. M. (1985). The effect of molecular weight on the physical properties of U.V. degraded natural rubber. European Polymer Journal, 21(1), 37-40. http://dx.doi.org/10.1016/0014-3057(85)90062-X.

6 Ono, K., Kato, A., & Murakami, K. (1985). Unusual stress-strain properties of natural rubber vulcanizates with high primary molecular weight. Polymer Bulletin, 13(1), 29-33. http://dx.doi.org/10.1007/BF00264237.

7 Huneau, B. (2011). Strain-induced crystallization of natural rubber: A review of x-ray diffraction investigations. Rubber Chemistry and Technology, 84(3), 425-452. http://dx.doi.org/10.5254/1.3601131.

8 Ehabe, E. E., Bonfils, F., Sainte-Beuve, J., Collet, A., & Schue, F. (2006). High-temperature mastication of raw natural rubber: changes in macrostructure and mesostructure. Polymer Engineering and Science, 46(2), 222-227. http://dx.doi.org/10.1002/pen.20433.

9 Hayeemasae, N., Waesateh, K., Soontaranon, S., & Masa, A. (2020). The effect of mastication time on the physical properties and structure of natural rubber. Journal of Elastomers and Plastics. http://dx.doi.org/10.1177/0095244320928566.

10 Dick, J. S. (2003). Basic rubber testing: selection methods for a rubber testing program. Pennsylvania: ASTM International. http://dx.doi.org/10.1520/MNL39-EB.

11 Khang, T. H., & Ariff, Z. M. (2012). Vulcanization kinetics study of natural rubber compounds having different formulation variables. Journal of Thermal Analysis and Calorimetry, 109(3), 1545-1553. http://dx.doi.org/10.1007/s10973-011-1937-3.

12 Flory, P. J., & Rehner, J. Jr (1943). Statistical mechanics of crossLinked polymer networks II. swelling. The Journal of Chemical Physics, 11(11), 521-526. http://dx.doi.org/10.1063/1.1723792.

13 Tosaka, M., Murakami, S., Poompradub, S., Kohjiya, S., Ikeda, Y., Toki, S., Sics, T., & Hsiao, B. S. (2004). Orientation and crystallization of natural rubber network as revealed by WAXD using synchrotron radiation. Macromolecules, 37(9), 3299-3309. http://dx.doi.org/10.1021/ma0355608.

14 Ikeda, Y., Yasuda, Y., Hijikata, K., Tosaka, M., & Kohjiya, S. (2008). Comparative study on strain-induced crystallization behavior of peroxide cross-linked and sulfur cross-linked natural rubber. Macromolecules, 41(15), 5876-5884. http://dx.doi.org/10.1021/ma800144u.

15 Somani, R. H., Yang, L., Zhu, L., & Hsiao, B. S. (2005). Flow-induced shish-kebab precursor structures in entangled polymer melts. Polymer, 46(20), 8587-8623. http://dx.doi.org/10.1016/j.polymer.2005.06.034.

16 Roe, R. J. (2000). Methods of x-ray and neutron scattering in polymer science. New York: Oxford University Press.

17 Lee, C. H., Saito, H., Inoue, T., & Nojima, S. (1996). Time-resolved small-angle x-ray scattering studies on the crystallization of poly(ethylene terephthalate). Macromolecules, 29(22), 7034-7037. http://dx.doi.org/10.1021/ma951828m.

18 Masa, A., Saito, H., Sakai, T., Kaesaman, A., & Lopattananon, N. (2017). Morphological evolution and mechanical property enhancement of natural rubber/polypropylene blend through compatibilization by nanoclay. Journal of Applied Polymer Science, 134(10), 44574. http://dx.doi.org/10.1002/app.44574.

19 Dimier, F., Vergnes, B., & Vincent, M. (2004). Relationships between mastication conditions and rheological behavior of a natural rubber. Rheologica Acta, 43(2), 196-202. http://dx.doi.org/10.1007/s00397-003-0342-7.

20 Smitthipong, W., Tantatherdtam, R., Rungsanthien, K., Suwanruji, P., Klanarong, S., Radabutra, S., Thanawan, S., Vallat, M. F., Nardin, M., Mougin, K., & Chollakup, R (2013). Effect of non-rubber components on properties of sulphur crosslinked natural rubbers. Advanced Materials Research, 844, 345-348. http://dx.doi.org/10.4028/www.scientific.net/AMR.844.345.

21 Kongkaew, C., Intiya, W., Loykulnant, S., & Sae-oui, P. (2017). Effect of protein crosslinking by maillard reaction on natural rubber properties. KGK. Kautschuk, Gummi, Kunststoffe, 5, 37-41.

22 Karaagac, B., Cengiz, S. C., Bayram, T., & Sen, M. (2018). Identification of temperature scanning stress relaxation behaviors of new grade ethylene propylene diene elastomers. Advances in Polymer Technology, 37(8), 3027-3037. http://dx.doi.org/10.1002/adv.21973.

23 Ray, S., & Cooney, R. P. (2018). Thermal degradation of polymer and polymer composites. In M. Kutz (Ed.), Handbook of environmental degradation of materials (pp. 185-206). Oxford: William Andrew Publishing. http://dx.doi.org/10.1016/B978-0-323-52472-8.00009-5.

24 Bueche, F. (1958). Mechanical properties of natural and synthetic rubbers. Rubber Chemistry and Technology, 31(1), 1-18. http://dx.doi.org/10.5254/1.3542259.

25 Tosaka, M. (2007). Strain-induced crystallization of crosslinked natural rubber as revealed by x-ray diffraction using synchrotron radiation. Polymer Journal, 39(12), 1207-1220. http://dx.doi.org/10.1295/polymj.PJ2007059.

26 Tosaka, M., Senoo, K., Kohjiya, S., & Ikeda, Y. (2007). Crystallization of stretched network chains in cross-linked natural rubber. Journal of Applied Physics, 101(8), 084909. http://dx.doi.org/10.1063/1.2716382.

27 Trabelsi, S., Albouy, P. A., & Rault, J. (2003). Crystallization and melting processes in vulcanized stretched natural rubber. Macromolecules, 36(20), 7624-7639. http://dx.doi.org/10.1021/ma030224c.

28 Chenal, M., Chazeau, L., Guy, L., Bomal, Y., & Gauthier, C. (2007). Molecular weight between physical entanglements in natural rubber: A critical parameter during strain-induced crystallization. Polymer, 48(4), 1042-1046. http://dx.doi.org/10.1016/j.polymer.2006.12.031.

29 Klug, H. P., & Alexander, L. E. (1974). X-ray diffraction procedures: For polycrystalline and amorphous materials. New York: Wiley.

30 Che, J., Burger, C., Toki, S., Rong, L., Hsiao, B. S., Amnuaypornsri, S., & Sakdapipanich, J. (2013). Crystal and crystallites structure of natural rubber and synthetic cis-1,4-polyisoprene by a new two dimensional wide angle x-ray diffraction simulation method, I, strain-induced crystallization. Macromolecules, 46(11), 4520-4528. http://dx.doi.org/10.1021/ma400420k.

31 Che, J., Burger, C., Toki, S., Rong, L., Hsiao, B. S., Amnuaypornsri, S., & Sakdapipanich, J. (2013). Crystal and crystallites structure of natural rubber and peroxide-vulcanized natural rubber by a two-dimensional wide-angle x-ray diffraction simulation method, II, strain-induced crystallization versus temperature-Induced crystallization. Macromolecules, 46(24), 9712-9721. http://dx.doi.org/10.1021/ma401812s.

32 Salgueiro, W., Somoza, A., Torriani, I. L., & Marzocca, A. J. (2007). Cure temperature influence on natural rubber - a small angle x-ray scattering study. Journal of Polymer Science. Part B, Polymer Physics, 45(21), 2966-2971. http://dx.doi.org/10.1002/polb.21293.

33 Masa, A., Soontaranon, S., & Hayeemasae, N. (2020). Influence of sulfur/accelerator ratio on tensile properties and structural inhomogeneity of natural rubber. Polymer, 44(4), 519-526. http://dx.doi.org/10.7317/pk.2020.44.4.519.

34 Weng, G., Huang, G., Lei, H., Qu, L., Nie, Y., & Wu, J. (2011). Crack initiation and evolution in vulcanized natural rubber under high temperature fatigue. Polymer Degradation & Stability, 96(12), 2221-2228. http://dx.doi.org/10.1016/j.polymdegradstab.2011.09.004.

35 Karino, T., Ikeda, Y., Yasuda, Y., Kohjiya, S., & Shibayama, M. (2007). Nonuniformity in natural rubber as revealed by small-angle neutron scattering, small-angle X-ray scattering, and atomic force microscopy. Biomacromolecules, 8(2), 693-699. http://dx.doi.org/10.1021/bm060983d. PMid:17243766.

36 Ikeda, Y., Higashitani, N., Hijikata, K., Kokubo, Y., Morita, Y., Shibayama, M., Osaka, N., Suzuki, T., Endo, H., & Kohjiya, S. (2009). Vulcanization: new focus on a traditional technology by small-angle neutron scattering. Macromolecules, 42(7), 2741-2748. http://dx.doi.org/10.1021/ma802730z.

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