Citation: Sheng Wang, Zheng-Hai Tang, Jing Huang, Bao-Chun Guo. Effects of Binding Energy of Bioinspired Sacrificial Bond on Mechanical Performance of cis-1,4-Polyisoprene with Dual-crosslink[J]. Chinese Journal of Polymer Science, ;2018, 36(9): 1055-1062. doi: 10.1007/s10118-018-2131-x shu

Effects of Binding Energy of Bioinspired Sacrificial Bond on Mechanical Performance of cis-1,4-Polyisoprene with Dual-crosslink

  • Corresponding author: Bao-Chun Guo, psbcguo@scut.edu.cn
  • Received Date: 19 December 2017
    Revised Date: 21 February 2018
    Accepted Date: 21 February 2018
    Available Online: 4 April 2018

  • Although bioinspired sacrificial bonds have been demonstrated to be efficient in improving the mechanical properties of polymer materials, the effect of binding energy of a specific dynamic bond on the ultimate mechanical performance of a polymer network with dual-crosslink remains unclear. In this contribution, diamine and sulfur curing package are introduced simultaneously into a sulfonated cis-1,4-polyisoprene to create dually-crosslinked cis-1,4-polyisoprene network with sulfonate-aminium ionic bonds as the sacrificial bonds. Three diamines (primary, secondary and tertiary) with the same spacer between the two nitrogen atoms are used to create the ionic bonds with different binding energies. Although the binding energy of ionic bond does not affect the glass transition temperature of cis-1,4-polyisoprene (IR), it exerts definite influences on strain-induced crystallization and mechanical performance. The capabilities of diamine in dissipating energy, promoting strain-induced crystallization and enhancing the mechanical performance are in the same order of secondary diamine > primary diamine > tertiary diamine. The variations in mechanical performances are correlated to the binding energy of the ionic bond, which is determined by p Ka values.
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    1. [1]

      Tanaka, Y. Structural characterization of natural polyisoprenes: solve the mystery of natural rubber based on structural study. Rubber Chem. Technol. 2001, 74(3), 355−375  doi: 10.5254/1.3547643

    2. [2]

      Hernandez, M.; Lopez-Manchado, M. A.; Sanz, A.; Nogales, A.; Ezquerra, T. A. Effects of strain-induced crystallization on the segmental dynamics of vulcanized natural rubber. Macromolecules 2011, 44(16), 6574−6580  doi: 10.1021/ma201021q

    3. [3]

      Amnuaypornsri, A.; Sakdapipanich, J.; Tanaka, Y. Green strength of natural rubber: the origin of the stress-strain behavior of natural rubber. J. Appl. Polym. Sci. 2009, 111(4), 2127−2133  doi: 10.1002/app.v111:4

    4. [4]

      Toki, S.; Sics, I.; Ran, S.; Liu, L.; Hsiao, B. S. New insights into structural development in natural rubber during uniaxial deformation by in situ synchrotron X-ray diffraction. Macromolecules 2002, 35(17), 6578−6584  doi: 10.1021/ma0205921

    5. [5]

      Toki, S.; Sics, I.; Hsiao, B. S.; Murakami, S.; Tosaka, M.; Poompradub, S.; Kohjiya, S.; Ikeda, Y. J. Structural developments in synthetic rubbers during uniaxial deformation by in situ synchrotron X-ray diffraction. J. Polym. Sci., Part B: Polym. Phys. 2004, 42(6), 956−964  doi: 10.1002/(ISSN)1099-0488

    6. [6]

      Kohjiya, S.; Tosaka, M.; Furutani, M.; Ikeda, Y.; Toki, S.; Hsiao, B. S. Role of stearic acid in the strain-induced crystallization of crosslinked natural rubber and synthetic cis-1,4-polyisoprene. Polymer 2007, 48(13), 3801−3848  doi: 10.1016/j.polymer.2007.04.063

    7. [7]

      Murakami, S.; Senoo, K.; Toki, S.; Kohjiya, S. Structural development of natural rubber during uniaxial stretching by in situ wide angle X-ray diffraction using a synchrotron radiation. Polymer 2002, 43(7), 2117−2120  doi: 10.1016/S0032-3861(01)00794-7

    8. [8]

      Trabelsi, S.; Albouy, P. A.; Rault, J. Stress-induced crystallization around a crack tip in natural rubber. Macromolecules 2002, 35(27), 10054−10061  doi: 10.1021/ma021106c

    9. [9]

      Liu, J.; Wu, S. W.; Tang, Z. H.; Lin, T. F.; Guo, B. C.; Huang, G. S. New evidence disclosed for networking in natural rubber by dielectric relaxation spectroscopy. Soft Matter 2015, 11(11), 2290−2299  doi: 10.1039/C4SM02521K

    10. [10]

      Liu, J.; Tang, Z. H.; Huang, J.; Guo, B. C.; Huang, G. S. Promoted strain-induced-crystallization in synthetic cis-1,4-polyisoprene via constructing sacrificial bonds. Polymer 2016, 97, 580−588  doi: 10.1016/j.polymer.2016.06.001

    11. [11]

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

    12. [12]

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

    13. [13]

      Toki, S.; Hsiao, B. S.; Amnuaypornsri, S.; Sakdapipanich, J. New insights into the relationship between network structure and strain-induced crystallization in un-vulcanized and vulcanized natural rubber by synchrotron X-ray diffraction. Polymer 2009, 50(9), 2142−2148  doi: 10.1016/j.polymer.2009.03.001

    14. [14]

      Amnuaypornsri, S.; Toki, S.; Hsiao, B. S.; Sakdapipanich, J. The effects of endlinking network and entanglement to stress-strain relation and strain-induced crystallization of unvulcanized and vulcanized natural rubber. Polymer 2012, 53(15), 3325−3330  doi: 10.1016/j.polymer.2012.05.020

    15. [15]

      Toki, S.; Che, J.; Rong, L. X.; Hsiao, B. S.; Amnuaypornsri, S.; Nimpaiboon, A.; Sakdapipanich, J. Entanglements and networks to strain-induced crystallization and stress-strain relations in natural rubber and synthetic polyisoprene at various temperatures. Macromolecules 2013, 46(13), 5238−5248  doi: 10.1021/ma400504k

    16. [16]

      Carretero-Gonzalez, J.; Verdejo, R.; Toki, S.; Hsiao, B. S.; Giannelis, E. P.; López-Manchado, M. A. Real-time crystallization of organoclay nanoparticle filled natural rubber under stretching. Macromolecules 2008, 41(7), 2295−2298  doi: 10.1021/ma7028506

    17. [17]

      Carretero-Gonzalez, J.; Retsos, H.; Verdejo, R.; Toki, S.; Hsiao, B. C.; Giannelis, E. P.; López-Manchado, M. A. Effect of nanoclay on natural rubber microstructure. Macromolecules 2008, 41(18), 6763−6772  doi: 10.1021/ma800893x

    18. [18]

      Wu, X.; Lin, T. F.; Tang, Z. H.; Guo, B. C.; Huang, G. S. Natural rubber/graphene oxide composites: effect of sheet size on mechanical properties and straininduced crystallization behavior. Express Polym. Lett. 2015, 9(80), 672−685

    19. [19]

      Nie, Y. J.; Huang, G. S.; Qu, L. L.; Wang, X. A.; Weng, G. S.; Wu, J. R. New insights into thermodynamic description of strain-induced crystallization of peroxide cross-linked natural rubber filled with clay by tube model. Polymer 2011, 52(14), 3234−3242  doi: 10.1016/j.polymer.2011.05.004

    20. [20]

      Bitinis, N.; Hernandez, M.; Verdejo, R.; Kenny, J. M.; Lopez-Manchado, M. A. Recent advances in clay/polymer nanocomposites. Adv. Mater. 2011, 23(44), 5229−5236  doi: 10.1002/adma.v23.44

    21. [21]

      Tang, Z. H.; Zhang, L. Q.; Feng, W. J.; Guo, B. C.; Liu, F.; Jia, D. M. Rational design of graphene surface chemistry for high performance rubber/graphene composites. Macromolecules 2014, 47(24), 8663−8673  doi: 10.1021/ma502201e

    22. [22]

      Kaang, S.; Gong, D.; Nah, C. Some physical characteristics of double-networked natural rubber. J. Appl. Polym. Sci. 1997, 65(5), 917−924  doi: 10.1002/(ISSN)1097-4628

    23. [23]

      Genesky, G. D.; Aguilera-Mercado, B. M.; Bhawe, D. M.; Escobedo, F. A.; Cohen, C. Experiments and simulations: enhanced mechanical properties of end-linked bimodal elastomers. Macromolecules 2008, 41(21), 8231−8241  doi: 10.1021/ma801065x

    24. [24]

      Becker, N.; Oroudjev, E.; Mutz, S.; Cleveland, J. P.; Hansma, P. K.; Hayashi, C. Y.; Makarov, D. E.; Hansma, H. G. Molecular nanosprings in spider capture-silk threads. Nat. Mater. 2003, 2, 278−283  doi: 10.1038/nmat858

    25. [25]

      Degtyar, E.; Harrington, M. J.; Politi, Y.; Fratzl, P. The mechanical role of metal ions in biogenic protein-based materials. Angew. Chem. Int. Ed. 2014, 53(45), 12026−12044  doi: 10.1002/anie.201404272

    26. [26]

      Fantner, G. E.; Hassenkam, T.; Kindt, J. H.; Weaver, J. C.; Birkedal, H.; Pechenik, L.; Cutroni, J. A.; Cidade, G. A.; Stucky, G. D.; Morse, D. E.; Hansma, P. K. Sacrificial bonds and hidden length dissipate energy as mineralized fibrils separate during bone fracture. Nat. Mater. 2005, 4(8), 612−616  doi: 10.1038/nmat1428

    27. [27]

      Wang, W. Y.; Elbanna, A. Crack propagation in bone on the scale of mineralized collagen fibrils: role of polymers with sacrificial bonds and hidden length. Bone 2014, 68, 20−31  doi: 10.1016/j.bone.2014.07.035

    28. [28]

      Fullenkamp, D. E.; He, L. H.; Barrett, D. G.; Burghardt, W. R.; Messersmith, P. B. Mussel-inspired histidine-based transient network metal coordination hydrogels. Macromolecules 2013, 46(3), 1167−1174  doi: 10.1021/ma301791n

    29. [29]

      Rose, S.; Dizeux, A.; Narita, T.; Hourdet, D.; Marcellan, A. Time dependence of dissipative and recovery processes in nanohybrid hydrogels. Macromolecules 2013, 46(10), 4095−4104  doi: 10.1021/ma400447j

    30. [30]

      Luo, F.; Sun, T. L.; Nakajima, T.; Kurokawa, T.; Zhao, Y.; Sato, K.; Ihsan, A. B.; Li, X.; Guo, H.; Gong, J. P. Oppositely charged polyelectrolytes form tough, self-healing, and rebuildable hydrogels. Adv. Mater. 2015, 27(17), 2722  doi: 10.1002/adma.v27.17

    31. [31]

      Gold, B. J.; Hovelmann, C. H.; Weiss, C.; Radulescu, A.; Allgaier, J.; Pyckhout-Hintzen, W.; Wischnewski, A.; Richter, D. Sacrificial bonds enhance toughness of dual polybutadiene networks. Polymer 2016, 87, 123−128  doi: 10.1016/j.polymer.2016.01.077

    32. [32]

      Luo, M. C.; Jian, Z.; Fu, X.; Huang, G. S.; Wu, J. R. Toughening diene elastomers by strong hydrogen bond interactions. Polymer 2016, 106, 21−28  doi: 10.1016/j.polymer.2016.10.056

    33. [33]

      Tang, Z. H.; Huang, J.; Guo, B. C.; Zhang, L. Q.; Liu, F. Bioinspired engineering of sacrificial metal-ligand bonds into elastomers with supramechanical performance and adaptive recovery. Macromolecules 2016, 49(5), 1781−1789  doi: 10.1021/acs.macromol.5b02756

    34. [34]

      Liu, J.; Wang, S.; Tang, Z. H.; Guo, B. C.; Huang, G. S. Bioinspired engineering of two different types of sacrificial bonds into chemically cross-linked cis-1,4-polyisoprene toward a high performance elastomer. Macromolecules 2016, 49(22), 8593−8604  doi: 10.1021/acs.macromol.6b01576

    35. [35]

      Faul, C. F. J.; Antonietti, M. Ionic self-assembly: facile synthesis of supramolecular materials. Adv. Mater. 2003, 15(9), 673−683  doi: 10.1002/adma.200300379

    36. [36]

      Malmierca, M. A.; GonzalezJimenez, A.; MoraBarrantes, I.; Posadas, P.; Rodriguez, A.; Ibarra, L.; Nogales, A.; Saalwachter, K.; Valentin, J. L. Characterization of network structure and chain dynamics of elastomeric ionomers by means of 1H low-field NMR. Macromolecules 2014, 47(16), 5655−5667  doi: 10.1021/ma501208g

    37. [37]

      Basu, D.; Das, A.; Stockelhuber, K. W.; Jehnichen, D.; Formanek, P.; Sarlin, E.; Vuorinen, J.; Heinrich, G. Evidence for an in situ developed polymer phase in ionic elastomers. Macromolecules 2014, 47(10), 3436−3450  doi: 10.1021/ma500240v

    38. [38]

      Sun, J. Y.; Zhao, X. H.; Illeperuma, W. R. K.; Chaudhuri, O.; Oh, K. H.; Mooney, D. J.; Vlassak, J. J.; Suo, Z. G. Highly stretchable and tough hydrogels. Nature 2012, 489(7414), 133−136  doi: 10.1038/nature11409

    39. [39]

      Makowski, H. S., Lundberg, R. D. and Singha, G. H., 1975, U.S. Pat., 3,870,841.

    40. [40]

      Zheng, L. Z.; Eisenberg, A. Dynamic mechanical properties of sulfonated cyclized cis-1,4-polyisoprene. Appl. Polym. Sci. 1982, 27(2), 657−671  doi: 10.1002/app.1982.070270229

    41. [41]

      Zhang, L.; Kucera, L. R.; Ummadisetty, S.; Nykaza, J. R.; Elabd, Y. A.; Storey, R. F.; Cavicchi, K. A.; Weiss, R. A. Supramoleclar multiblock polystyrene-polyisobutylene copolymers via ionic interactions. Macromolecules 2014, 47(13), 4387−4396  doi: 10.1021/ma500934e

    42. [42]

      Mohammed, O. F.; Pines, D.; Dreyer, J. Sequential proton transfer through water bridges in acid-base reactions. Science 2005, 310(5745), 83−86  doi: 10.1126/science.1117756

    43. [43]

      Yount, W. C.; Loveless, D. M.; Craig, S. L. Small-molecule dynamics and mechanisms underlying the macroscopic mechanical properties of coordinatively cross-linked polymer networks. J. Am. Chem. Soc. 2005, 127(41), 14488−14496  doi: 10.1021/ja054298a

    44. [44]

      Yount, W. C.; Loveless, D. M.; Craig, S. L. Strong means slow: dynamic contributions to the bulk mechanical properties of supramolecular networks. Angew. Chem. Int. Ed. 2005, 44(18), 2746−2748  doi: 10.1002/(ISSN)1521-3773

    45. [45]

      Meyers, M. A.; Mckittrick, J.; Chen, P. Y. Structural biological materials: critical mechanics materials connections. Science 2013, 339(6121), 773−779  doi: 10.1126/science.1220854

    46. [46]

      Fu, X.; Huang, G. S.; Xie, Z. T.; Wang, X. New insights into reinforcement mechanism of nanoclay-filled isoprene rubber during uniaxial deformation by in situ synchrotron X-ray diffraction. RSC Adv. 2015, 5(32), 25171−25182  doi: 10.1039/C5RA02123E

    47. [47]

      Wu, S. W.; Qiu, M.; Tang, Z. H.; Liu, J.; Guo, B. C. Carbon nanodots as high-functionality cross-linkers for bioinspired engineering of multiple sacrificial units toward strong yet tough elastomers. Macromolecules 2017, 50(8), 3244−3253  doi: 10.1021/acs.macromol.7b00483

    48. [48]

      Weng, G. S.; Huang, G. S.; Qu, L. L.; Nie, Y. J.; Wu, J. R. Large-scale orientation in a vulcanized stretched natural rubber network: proved by in situ synchrotron X-ray diffraction characterization. J. Phys. Chem. B 2010, 114(21), 7179−7188  doi: 10.1021/jp100920g

    49. [49]

      Ren, Y. H.; Zhao, S. H.; Yao, Q.; Li, Q. Q.; Zhang, X. Y.; Zhang, L. Q. Effects of plasticizers on the strain-induced crystallization and mechanical properties of natural rubber and synthetic polyisoprene. RSC Adv. 2015, 5(15), 11317−11324  doi: 10.1039/C4RA13504K

    50. [50]

      Qu, L. L.; Huang, G. S.; Zhang, Z. P.; Nie, Y. J.; Weng G. S.; Wu, J. R. Synergistic reinforcement of nanoclay and carbon black in natural rubber. Polym. Int. 2010, 59(10), 1397−1402  doi: 10.1002/pi.v59:10

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