Sains Malaysiana 44(6)(2015): 811–818

Self-healing of Poly(2-hydroxyethyl methacrylate) Hydrogel through Molecular Diffusion

(Swa-Pemulihan Hidrogel Poli(2-hidroksietil metakrilat) melalui Penyusupan Rawak Molekul)

N.A. SIRAJUDDIN & M.S. MD JAMIL*

Faculty of Science and Technology, Universiti Kebangsaan Malaysia

43600 Bangi, Selangor Darul Ehsan, Malaysia

Diserahkan: 15 Januari 2014/Diterima: 15 November 2014

ABSTRACT

Synthetic materials that are capable of healing upon damage are being developed at a rapid pace because of their many potential applications. Here, new healing chemically cross-linked hydrogel of poly(2-hydroxyethyl methacrylate) (pHEMA) was prepared. The healing hydrogel was achieved by heating above its glass transition (Tg). The intermolecular diffusion of dangling chain and the chain slippage led to healing of the gel. The peaks in attenuated total reflectance (ATR) confirmed that hydrogel was formed while rheological studies had determined the minimum for healing temperature is 48.5oC. The results showed that ratio stress of the healable hydrogel can reach until 92 and 91% of first and second healing cycle, respectively. The morphology of the sample was carried out to evaluate the self-property of hydrogel.

Keywords: Chain slippage; intermolecular diffusion; self-healing hydrogel; temperature

ABSTRAK

Keupayaan swa-pemulihan pada bahan sintetik banyak digunakan dalam aplikasi perubatan serta aplikasi-aplikasi yang berkaitan. Suatu hidrogel baharu iaitu poli(hidrosietil metakrilat) telah disediakan melalui tindak balas kimia. Swa-pemulihan hidrogel berlaku apabila diberikan haba melebihi suhu peralihan kaca (Tg) dan gel yang telah dipotong bercantum semula melalui proses penyusupan rawak molekul dan penggelinciran rantai. Puncak spektrum yang ditunjukkan dalam ATR mengesahkan proses taut silang yang berlaku dalam hidrogel tersebut. Suhu pemulihan minimum pula telah ditentukan oleh kajian reologi. Hasil ujian tensil membuktikan kekuatan hidrogel pemulihan berupaya mencapai sehingga 92% pada kitaran pertama dan 91% pada kitaran kedua. Ujian morfologi telah dijalankan bagi mengenal pasti sifat pemulihan hidrogel tersebut.

Kata kunci: Penggelinciran rantai; penyusupan molekul; suhu; swa-pemulihan hydrogel

RUJUKAN

ASTM D5045-99. 2007. Standard Test Methods for Plane-strain Fracture Toughness and Strain Energy Release Rate of Plastic Materials. American Society for Testing and Materials.

Begley, T.H., Brandsch, J., Limm, W., Siebert, H. & Piringer, O. 2008. Diffusion behaviour of additives in polypropylene in correlation with polymer properties. Food Additives & Contaminants Part A, Chemistry, Analysis, Control, Exposure & Risk Assessment 25(11): 1409-1415.

Belma, ISIK. 2000. Swelling behaviour of acrylamide-2- hydroxyethyl methacrylate hydrogels. Turkish Journal of Chemistry 24: 147-156.

Bergman, S.D. & Wudl, F. 2008. Mendable polymers. Journal of Materials Chemistry 18: 41-62.

Bhalekar, M., Sonawane, S. & Shimpi, S. 2013. Synthesis and characterization of a cysteine xyloglucan as mucoadhesive polymer. Brazilian Journal of Pharmaceutical Science 49(2): 285-292.

Blaiszik, B.J., Kramer, S.L.B., Olugebefola, S.C., Moore, J.S., Sottos, N.R. & White, S.R. 2010. Self-healing polymer and composite - Autonomous materials systems. Annual Review of Materials Research 40: 179-211.

Billiet, S., Hillewaere, X.K., Teixeira, R.F. & Du Prez, F.E. 2013. Chemistry of crosslinking processes for self-healing polymers. Macromolecular Rapid Communications 34(4): 290-309.

Chen, Y., Kushner, A.M., Williams, G.A. & Guan, Z. 2012. Multiphase design of autonomic self-healing thermoplastic elastomers. Nature Chemistry 4: 467-472.

Deng, G., Li, F., Yu, H., Liu, F., Liu, C., Sun, W., Jiang, H. & Chen, Y. 2012. Dynamic hydrogels with an environmental adaptive self-healing ability and dual responsive sol-gel transitions. ACS Macro Letters 1: 275-279.

Dohler, D., Michael, P. & Binder, W. 2013. Principles of self-healing polymers. In Self-Healing Polymers: From Principles to Applications, edited by Binder, W.H. New York: Wiley- VCHVerlag GmbH & Co. KGaA. pp. 5-60.

Ferry, J.D. 1980. The colloidal structure of bitumen: Consequences on the rheology and on the mechanisms of bitumen modification. In Viscoelastic Properties of Polymers. 3rd ed. New York: Wiley & Sons.

Lee, J., Bhattacharyya, D., Zhang, M.Q. & Yuan, Y.C. 2011. Fracture behaviour of a self-healing microcapsule-loaded epoxy system. Express Polymer Letters 5(3): 246-253.

Lesueur, D. 2009. The colloidal structure of bitumen: Consequences on the rheology and on the mechanisms of bitumen modification. Advances in Colloid and Interface Science 145: 42-82.

Maes, F., Montarnal, D., Cantournet, S., Tournilhac, F., Corte, L. & Leibler, L. 2012. Activation and deactivation of self-healing in supramolecular rubbers. Soft Material 8: 1681- 1687.

Moura, M.J., Figueiredo, M.M. & Gil, M.H. 2007. Rheological study of genipin cross-linked chitosan hydrogels. Biomacromolecules 8: 3823-3829.

Murphy, E.B. & Wudl, F. 2010. The world of smart healable materials. Progress in Polymer Science 35: 223-251.

Pavlos, S., Stephanoul, Chunggi, B., Georgia, T., Vlasis, G.M. & Martin, K. 2010. Quantifying chain reptation in entangled polymer melts: Topological and dynamical mapping of atomistic simulation results onto the tube model. Journal of Chemical Physics 132(12): 1-16.

Phadke, A., Zhang, C., Arman, B., Hsu, C.C., Mashelkar, R.A., Lele, A.K., Tauber, M.J., Arya, G. & Varghese, S. 2012. Rapid self-healing hydrogels. Proceeding of the National Academy Science of U.S.A. 109: 4383-4388.

Radi, B., Wellard, R.M. & George, G.A. 2013. Effect of dangling chains on the structure and physical properties of a tightly crosslinked poly(ethylene glycol) network. Soft Material 9: 3262-3271.

Tang, Y.F., Du, Y.M., Hu, X.W., Shi, X.W. & Kennedy, J.F. 2007. Rheological characterization of a novel thermo-sensitive chitosan/poly(vinyl alcohol) blend hydrogel. Carbohydrate Polymers 67: 491-499.

Wool, R.P. 2008. Self-healing materials: A review. Soft Material 4(3): 400-418.

Wool, R.P. 1994. Polymer Interfaces: Structure and Strength. Cincinnati, New York: Hanser Gardner. pp. 445-479.

Wool, R.P. 1993. Polymer Entanglements. Macromolecules 26: 1564-1569.

Wool, R. & O’Connor, K. 1983. Theory of crack healing in polymers. Journal of Applied Physics 52(10): 5953-5963.

Yamaguchi, M., Ono, S. & Okamoto, K. 2009. Interdiffusion of dangling chains in weak gel and its application to self-repairing material. Materials Science Engineering B 162(3): 189-194.

Yajuan, Y., Qingzhi, L., Lianying, W. & Yangdong, H. 2012. Molecular dynamics simulation for diffusion of organic molecules in polyethylene membranes. Journal CIESC 63(1): 113-113.

Zhang, L., Zheng, G.J., Guo, Y.T., Zhou, L., Du, J. & He, H. 2014. Preparation of novel biodegradable pHEMA hydrogel for a tissue engineering scaffold by microwave-assisted polymerization. Asian Pacific Journal of Tropical Medicine 136-140.

Zhao, Y., Gao, S., Zhao, S., Li, Y., Cheng, L., Li, J. & Yin, Y. 2012. Synthesis and characterization of disulfide-crosslinked alginate hydrogel scaffolds. Materials Science and Engineering C 32: 2153-2162.

*Pengarang untuk surat-menyurat; email: suzeren@ukm.edu.my