English

Cross-Linkable Yet Biodegradable Polymer Films

• Shuai Chen ^{1, 2,} ,
• Jianglei Qin ^{3, 4, ,} ,
• Jianzhong Du ^{1, 2, ,}

• 1.

  Department of Orthopedics, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai 200072, China.

• 2.

  Department of Polymeric Materials, School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.

• 3.

  College of Chemistry and Environmental Science, Hebei University, Baoding 071002, Hebei Province, China.

• 4.

  State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China

Corresponding author: Jianglei Qin, qinhbu@iccas.ac.cn Jianzhong Du, jzdu@tongji.edu.cn

• Received Date: 11 June 2020
  Accepted Date: 27 July 2020
  Revised Date: 27 July 2020
  Available Online: 15 August 2022
• Fund Project:

Abstract: Polymer films are widely used as biomaterials, electronic devices, food packaging materials and gas separation membranes. In practice, cross-linking is an effective method to enhance their stability and increase the strength of these films. However, conventional cross-linked polymer films cannot degrade under mild conditions. Herein, we fabricated two cross-linkable, yet biodegradable, polymer films of ~0.2 mm via solution casting using cinnamate-grafted polycaprolactones, namely: a poly((α-(cinnamoyloxymethyl)-1, 2, 3-triazol) caprolactone) (PCTCL₁₃₃) homopolymer and a poly(caprolactone-stat-CTCL) (P(CL₁₅₆-stat-CTCL₂₈)) copolymer. The successful syntheses of the polymers were confirmed via proton nuclear magnetic resonance (¹H NMR) spectroscopy, size exclusion chromatography (SEC), and Fourier transform infrared (FT-IR) spectroscopy. The PCTCL homopolymer appeared as a transparent film, owing to its side groups that impede its crystallinity; in contrast, the copolymer film appeared translucent, owing to its PCL segments that are easily crystallized. The cinnamate groups facilitated the cross-linking of the polymer films when irradiated by ultraviolet (UV) light; this is indicated by its insoluble character in tetrahydrofuran, which is a good solvent for both polymers. SEC analysis indicated that a fraction of the P(CL₁₅₆-stat-CTCL₂₈) film remained un-cross-linked after irradiation, owing to its crystalline structure. In contrast, UV irradiation caused the PCTCL homopolymer film to become homogeneously cross-linked, which exhibited a cross-linking density of 49% after 2 h as indicated by the ¹H NMR results. Thermogravimetric analysis (TGA) indicated that cross-linking of the PCTCL films caused a minimal change in thermal stability. Both the cross-linked polymer films were able to degrade upon the addition of a modest amount of concentrated hydrochloric acid, as confirmed by SEC and ¹H NMR. However, the degradation rate significantly decreased after cross-linking, thereby indicating its tunable character that can be altered by varying the cross-linking density. In addition, the rate of degradation can be adjusted upon varying the fraction of cross-linked PCTCL groups in the copolymer. In principle, treating the polymer films with sufficient amounts of acid could form degradation products with molecular weights less than 300 g∙mol⁻¹. To further explore the mechanical properties of such materials, we investigated the correlation between the initial concentration used for solution casting and the Young's modulus of the film by employing molecular dynamics simulations. These results indicate that tougher films are prepared when using more concentrated polymer solutions, owing to a higher degree of chain entanglement. In summary, the prepared films with tunable degradability are promising materials for biomedical applications. In principle, this platform could be utilized in hydrogels and coating materials for a broad scope of applications.

Key words:
• Polymer film
•  /  Polycaprolactone
•  /  Photocross-linking
•  /  Degradability
•  /  Solution casting

• 1. [1]

     Cheng, C.; Sun, S. D.; Zhao, C. S. J. Mater. Chem. B 2014, 2, 7649. doi: 10.1039/c4tb01390e

  2. [2]

     Chen, X. Y.; Li, J. S. Mater. Chem. Front. 2020, 4, 750. doi: 10.1039/c9qm00717b

  3. [3]

     Tharanathan, R. N. Trends Food Sci. Technol. 2003, 14, 71. doi: 10.1016/S0924-2244(02)00280-7

  4. [4]

     Bao, Q. Y.; Braun, S.; Wang, C. F.; Liu, X. J.; Fahlman, M. Adv. Mater. Interfaces 2019, 6, 1800897. doi: 10.1002/admi.201800897

  5. [5]

     Pandey, P.; Chauhan, R. S. Prog. Polym. Sci. 2001, 26, 853. doi: 10.1016/S0079-6700(01)00009-0

  6. [6]

     Reddy, N.; Reddy, R.; Jiang, Q. R. Trends Biotechnol. 2015, 33, 362. doi: 10.1016/j.tibtech.2015.03.008

  7. [7]

     Rhim, J. W.; Ng, P. K. W. Crit. Rev. Food Sci. Nutr. 2007, 47, 411. doi: 10.1080/10408390600846366

  8. [8]

     Feng, C.; Huang, X. Y. Acc. Chem. Res. 2018, 51, 2314. doi: 10.1021/acs.accounts.8b00307

  9. [9]

     Xu, B. B.; Feng, C.; Hu, J. H.; Shi, P.; Gu, G. X.; Wang, L.; Huang, X. Y. ACS Appl. Mater. Interfaces 2016, 8, 6685. doi: 10.1021/acsami.5b12820

  10. [10]

      Xu, B. B.; Liu, Y. J.; Sun, X. W.; Hu, J. H.; Shi, P.; Huang, X. Y. ACS Appl. Mater. Interfaces 2017, 9, 16517. doi: 10.1021/acsami.7b03258

  11. [11]

      Sionkowska, A. Prog. Polym. Sci. 2011, 36, 1254. doi: 10.1016/j.progpolymsci.2011.05.003

  12. [12]

      Baroli, B. J. Biomed. Nanotechnol. 2010, 6, 485. doi: 10.1166/jbn.2010.1147

  13. [13]

      Chandra, R.; Rustgi, R. Prog. Polym. Sci. 1998, 23, 1273. doi: 10.1016/S0079-6700(97)00039-7

  14. [14]

      Kweon, H.; Yoo, M. K.; Park, I. K.; Kim, T. H.; Lee, H. C.; Lee, H. S.; Oh, J. S.; Akaike, T.; Cho, C. S. Biomaterials 2003, 24, 801. doi: 10.1016/S0142-9612(02)00370-8

  15. [15]

      陈灵珊, 洪苑秀, 贺石生, 范震, 杜建忠. 物理化学学报, 2020, 36, 1910059. doi: 10.3866/PKU.WHXB201910059Chen, L. S.; Hong, Y. X.; He, S. S.; Fan, Z.; Du, J. Z. Acta Phys. -Chim. Sin. 2020, 36, 1910059. doi: 10.3866/PKU.WHXB201910059

  16. [16]

      宋涛, 奚悦静, 杜建忠. 高分子学报, 2018, No. 1, 119. doi: 10.11777/j.issn1000-3304.2018.17229Song, T.; Xi, Y. J.; Du, J. Z. Acta Polym. Sin. 2018, No. 1, 119. doi: 10.11777/j.issn1000-3304.2018.17229

  17. [17]

      Lo, H. Y.; Kuo, H. T.; Huang, Y. Y. Artif. Organs 2010, 34, 648. doi: 10.1111/j.1525-1594.2009.00949.x

  18. [18]

      Shi, D. L.; He, T.; Tang, W. J.; Li, H. Z.; Wang, C.; Zheng, M. Z.; Hu, J.; Song, X. H.; Ding, Y. M.; Chen, Y. Y.; et al. Neurosci. Lett. 2019, 694, 161. doi: 10.1016/j.neulet.2018.12.006

  19. [19]

      Zhang, Q.; Jiang, Y.; Zhang, Y.; Ye, Z.; Tan, W.; Lang, M. Polym. Degrad. Stab. 2013, 98, 209. doi: 10.1016/j.polymdegradstab.2012.10.008

  20. [20]

      Sun, H. F.; Mei, L.; Song, C. X.; Cui, X. M.; Wang, P. Y. Biomaterials 2006, 27, 1735. doi: 10.1016/j.biomaterials.2005.09.019

  21. [21]

      Zou, Y. J.; He, S. S.; Du, J. Z. Chin. J. Polym. Sci. 2018, 36, 1239. doi: 10.1007/s10118-018-2156-1

  22. [22]

      Liu, G. J.; Ding, J. F.; Hashimoto, T.; Kimishima, K.; Winnik, F. M.; Nigam, S. Chem. Mater. 1999, 11, 2233. doi: 10.1021/cm990184k

  23. [23]

      廖雨瑶, 范震, 杜建忠. 物理化学学报, 2020, 36, 1912053. doi: 10.3866/PKU.WHXB201912053Liao, Y. Y.; Fan, Z.; Du, J. Z. Acta Phys. -Chim. Sin. 2020, 36, 1912053. doi: 10.3866/PKU.WHXB201912053

  24. [24]

      袁康, 周雪, 杜建忠. 物理化学学报, 2017, 33, 656. doi: 10.3866/PKU.WHXB201701162Yuan, K.; Zhou, X.; Du, J. Z. Acta Phys. -Chim. Sin. 2017, 33, 656. doi: 10.3866/PKU.WHXB201701162

  25. [25]

      Xiao, Y. F.; Sun, H.; Du, J. Z. J. Am. Chem. Soc. 2017, 139, 7640. doi: 10.1021/jacs.7b03219

  26. [26]

      Groschel, A. H.; Schacher, F. H.; Schmalz, H.; Borisov, O. V.; Zhulina, E. B.; Walther, A.; Muller, A. H. E. Nat. Commun. 2012, 3, 710. doi: 10.1038/ncomms1707

  27. [27]

      Du, J. Z.; Chen, Y. M.; Zhang, Y. H.; Han, C. C.; Fischer, K.; Schmidt, M. J. Am. Chem. Soc. 2003, 125, 14710. doi: 10.1021/ja0368610

  28. [28]

      Qin, J. L.; Jiang, X. B.; Gao, L.; Chen, Y. M.; Xi, F. Macromolecules 2010, 43, 8094. doi: 10.1021/ma101639w

  29. [29]

      Peng, B.; Liu, Y.; Shi, Y.; Li, Z. B.; Chen, Y. M. Soft Matter 2012, 8, 12002. doi: 10.1039/c2sm26638e

  30. [30]

      Pitt, C. G.; Hendren, R. W.; Schindler, A.; Woodward, S. C. J. Controlled Release 1984, 1, 3. doi: 10.1016/0168-3659(84)90016-6

  31. [31]

      Shen, J. Y.; Pan, X. Y.; Lim, C. H.; Chan-Park, M. B.; Zhu, X.; Beuerman, R. W. Biomacromolecules 2007, 8, 376. doi: 10.1021/bm060766c

  32. [32]

      Gunatillake, P. A.; Adhikari, R. Eur. Cells Mater. 2003, 5, 1. doi: 10.22203/ecm.v005a01

  33. [33]

      Kamada, J.; Koynov, K.; Corten, C.; Juhari, A.; Yoon, J. A.; Urban, M. W.; Balazs, A. C.; Matyjaszewski, K. Macromolecules 2010, 43, 4133. doi: 10.1021/ma100365n

  34. [34]

      Tsarevsky, N. V.; Matyjaszewski, K. Macromolecules 2005, 38, 3087. doi: 10.1021/ma050020r

  35. [35]

      Jiang, X. B.; Chen, Y. M.; Xi, F. Macromolecules 2010, 43, 7056. doi: 10.1021/ma101460n

  36. [36]

      Wiltshire, J. T.; Qiao, G. G. Macromolecules 2006, 39, 9018. doi: 10.1021/ma0622027

  37. [37]

      Wiltshire, J. T.; Qiao, G. G. Macromolecules 2006, 39, 4282. doi: 10.1021/ma060712v

  38. [38]

      Deng, G. H.; Tang, C. M.; Li, F. Y.; Jiang, H. F.; Chen, Y. M. Macromolecules 2010, 43, 1191. doi: 10.1021/ma9022197

  39. [39]

      Imato, K.; Nishihara, M.; Kanehara, T.; Amamoto, Y.; Takahara, A.; Otsuka, H. Angew. Chem., Int. Ed. 2012, 51, 1138. doi: 10.1002/anie.201104069

  40. [40]

      Haraguchi, K.; Uyama, K.; Tanimoto, H. Macromol. Rapid Commun. 2011, 32, 1253. doi: 10.1002/marc.201100248

  41. [41]

      Du, H.; Zha, G. Y.; Gao, L. L.; Wang, H.; Li, X. D.; Shen, Z. Q.; Zhu, W. P. Polym. Chem. 2014, 5, 4002. doi: 10.1039/c4py00030g

  42. [42]

      Atzet, S.; Curtin, S.; Trinh, P.; Bryant, S.; Ratner, B. Biomacromolecules 2008, 9, 3370. doi: 10.1021/bm800686h

  43. [43]

      Darwis, D.; Mitomo, H.; Yoshii, F. Polym. Degrad. Stab. 1999, 65, 279. doi: 10.1016/S0141-3910(99)00017-8

  44. [44]

      Defize, T.; Riva, R.; Raquez, J.-M.; Dubois, P.; Jérôme, C.; Alexandre, M. Macromol. Rapid Commun. 2011, 32, 1264. doi: 10.1002/marc.201100250

  45. [45]

      Riva, R.; Schmeits, S.; Stoffelbach, F.; Jérôme, C.; Jérôme, R.; Lecomte, P. Chem. Commun. 2005, No. 42, 5334. doi: 10.1039/b510282k

  46. [46]

      Chiu, F. C.; Wang, S. W.; Peng, K. Y.; Lee, R. S. Polymer 2012, 53, 3476. doi: 10.1016/j.polymer.2012.06.004

  47. [47]

      Gupta, P.; Trenor, S. R.; Long, T. E.; Wilkes, G. L. Macromolecules 2004, 37, 9211. doi: 10.1021/ma048844g

  48. [48]

      Rochette, J. M.; Ashby, V. S. Macromolecules 2013, 46, 2134. doi: 10.1021/ma302354a

  49. [49]

      Belsito, D.; Bickers, D.; Bruze, M.; Calow, P.; Greim, H.; Hanifin, J. M.; Rogers, A. E.; Saurat, J. H.; Sipes, I. G.; Tagami, H. Food Chem. Toxicol. 2007, 45, S1. doi: 10.1016/j.fct.2007.09.087

  50. [50]

      Chen, S.; Qin, J. L.; Du, J. Z. Macromolecules 2020, 53, 3978. doi: 10.1021/acs.macromol.0c00252

  51. [51]

      Lenoir, S.; Riva, R.; Lou, X.; Detrembleur, C.; Jérôme, R.; Lecomte, P. Macromolecules 2004, 37, 4055. doi: 10.1021/ma035003l

  52. [52]

      Chen, J. C.; Liu, M. Z.; Gong, H. H.; Huang, Y. J.; Chen, C. J. Phys. Chem. B 2011, 115, 14947. doi: 10.1021/jp208494w

  53. [53]

      Cintas, P.; Barge, A.; Tagliapietra, S.; Boffa, L.; Cravotto, G. Nat. Protoc. 2010, 5, 607. doi: 10.1038/nprot.2010.1

  54. [54]

      Ge, T.; Pierce, F.; Perahia, D.; Grest, G. S.; Robbins, M. O. Phys. Rev. Lett. 2013, 110, 098301. doi: 10.1103/PhysRevLett.110.098301

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