Process for preparing quick response temperature sensitive water gel

Abstract

The present invention discloses preparation process of quick response temperature sensitive water gel. Monomer N-isopropyl acrylamide, cross-linking agenet N, N-methylene bisacrylamide, initiator azo diisobutyronitrile, chain transferring agent, solvent 1, 4-dioxane and other reaction materials are made to react at 40-80 deg.c in a container first vacuumized and then filled with nitrogen for 6-48 hr to obtain gel, which is then soaked in water to eliminate residual reaction materials so as to obtain the quick response temperature sensitive water gel. The quick response temperature sensitive water gel of the present invention has quick response rate, fast dewatering performance and simple preparation process.

Description

technical field [0001] The invention relates to the field of functional polymers, in particular to a method for preparing a fast-response temperature-sensitive hydrogel. Background technique [0002] Thermosensitive hydrogels, especially poly-N-isopropylacrylamide (PNIPAM) hydrogels, are currently the most widely studied smart hydrogels. When the temperature is higher or lower than the lower critical solution temperature (LCST) value of PNIPAM hydrogel, PNIPAM hydrogel is in shrinkage or swelling state respectively, meanwhile, the interaction parameter of this hydrogel, modulus, refractive index, The dielectric constant, optical anisotropy, etc. will also change abruptly, and these changes are often reversible. The mutated characteristics of PNIPAM hydrogel with the change of environmental temperature make it have good application prospects, and can be used in the fields of immobilized enzymes, material extraction, cell culture, temperature-sensit...

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Problems solved by technology

For example, WuXS et al [WuXS, Hoffman A S, Paul Y.J Polym Sci, Part A: Polym Chem, 1992, 30: 2121-2129] proposed to introduce a porous or superporous structure into the hydrogel, they used hydroxypropyl cellulose A macroporous PNIPAM hydrogel was synthesized as a pore-forming agent at a temperature higher than the lower critical temperature, but this method has high requirements on the performance of the pore-forming agent, and the process is complicated, and the pore-forming agent needs to be extracted in the subsequent process

Yoshida et al. [Yoshida R, Uchida U, Kaneko Y, et al. Nature, 1995, 374: 240-242] proposed to introduce grafted chains into the hydrogel, but this method is complex and requires multi-step synthesis. It is difficult to apply in the actual production process

Zhang et al. [Zhang X Z, Zhang J T, Zhuo R X, et al. Polymer, 2002, 43: 4823-4827] proposed to use phase separation technology, that is, to use water / tetrahydrofuran as a mixed solvent to form a copolymer in PNIPAM hydrogel through a copolymerization reaction. A crown ether derivative: 4'-allyldibenzo-18-crown-6 (CE) was introduced by valent way, but this heterogeneous structure is difficult to control

Zhibing Hu et al [Hu Z., Lu X, Gao J, Wang C. Advanced Materials 2000; 12: 173] first prepared nanoparticles with functional groups, and then connected these particles through chemical bonds to prepare a Nanocomposite hydrogels, but the reaction process of this method is difficult to control

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