Temperature-responsive N-isopropylacrylamide-grafted natural rubber
- 144 Downloads
Temperature-responsive polymers are smart materials that respond to changes in temperature and have a wide range of applications, ranging from sensing to biomedical fields. In this work, we investigated the synthesis and temperature-responsive behavior of responsive elastomer based on N-isopropylacrylamide-grafted natural rubber. The grafting reaction was carried out using deproteinized natural rubber (DPNR) latex and potassium persulfate as free radical initiator. The temperature responsiveness of the graft copolymers was investigated using water swelling and contact angle measurements, and compared with that of pure DPNR. The lower critical solution temperature of the graft copolymer was found to be in the range 30–34 °C, whereas the DPNR was not responsive to temperature. Furthermore, the graft copolymer exhibited temperature responsiveness in a solid state. As the temperature responsiveness of the graft copolymer is close to the human body temperature, it can be used in biomedical applications. Dye adsorption studies revealed the Langmuir isotherm, indicating monolayer coverage. The technique proposed in this study produces a temperature-responsive natural rubber, with potential applications as a responsive material for use in sensing and biomedical products.
KeywordsTemperature responsive N-isopropylacrylamide Deproteinization Natural rubber Graft copolymer
This work is financially supported by the Thailand Research Fund (TRF) and the Faculty of Science and Technology, Thammasat University (TRG5880199) and the Thailand Graduate Institute of Science and Technology (TGIST: SCA-CO-2558-996-TH). The authors acknowledge the Central Scientific Instrument Center (CSIC), Department of Chemistry, Faculty of Science and Technology, and Thammasat University.
- 1.Almeida H, Amaral MH, Lobão P (2012) Temperature and pH stimuli-responsive polymers and their applications in controlled and self-regulated drug delivery. J Appl Pharm Sci 02:01–10Google Scholar
- 4.Mark B, Overberger CG, Menges G (1986) Encyclopedia of polymer science and engineering. Wiley 6:492Google Scholar
- 18.Graves DF (2007) Rubber. In: Kent JA (ed) Handbook of industrial chemistry and biotechnology. Springer, New York, pp 689–718Google Scholar
- 29.Promdum Y, Klinpituksa P, Ruamcharoen J (2009) Grafting copolymerization of natural rubber with 2-hydroxyethyl methacrylate for plywood adhesion improvement. Songklanakarin J Sci Technol 31:453–457Google Scholar
- 32.Wongthong P, Nakason C, Pan Q, Rempel GL, Kiatkamjornwong S (2012) Grafting of maleic anhydride onto deproteinized natural rubber via differential microemulsion polymerization. Adv Trends Eng Mater Appl 183–190Google Scholar
- 35.Oshio A, Kitai T, Kawahara S, Kuroda H (2006) Investigation of high graft-copolymerization of styrene onto natural rubber. In: Polymer preprints, vol 55. Japan, p 3606Google Scholar
- 48.Seddiki N, Aliouche D (2013) Synthesis, rheological behavior and swelling properties of copolymer hydrogels based on poly(N-isopropylacrylamide) with hydrophilic monomers. Bull Chem Soc Ethiop 27:447Google Scholar
- 54.Chen X (2015) Modeling of experimental adsorption isotherm data. Information 4:14–22Google Scholar
- 56.Itodo AU, Itodo HU (2010) Sorption energies estimation using Dubinin–Radushkevich and Temkin adsorption isotherms. Life Sci J 7:31–39Google Scholar