Design of Functional Polymer Gels and Their Application to Biomimetic Materials

Abstract

Over about the last two decades, many kinds of stimuli-responsive polymer gels in response to the change in their surroundings such as solvent composition, temperature, pH, and supply of electric field, etc., have been developed. They have attracted much attention as intelligent (or smart, biomimetic) materials which have sensor, processor and actuator functions. Applications to actuator (artificial muscle), biosensor, drug delivery systems, purification or separation systems, etc. are extensively studied. In this review, design of stimuli-responsive gels and their application to bio-or biomimetic materials will be discussed as well as our recent studies on novel self-oscillating gels.

Biomimetic mechanically adaptive nanocomposites

“…Other classes of widely investigated mechanically adaptable materials include temperature and chemo-responsive polymer (hydro)gels and networks [6][7][8], photo-responsive gels [9], liquid-crystalline elastomers [10], electro-rheological fluids and gels [11], as well as materials that undergo dimensional changes upon stimulation, for example electrostrictive materials [12]. While the mechanical changes of these materials can be quite dramatic -some exhibit viscosity/modulus changes of several orders of magnitude -the large majority of these mechano-responsive materials exhibit a very low modulus [13]. While their property profiles are ideal for applications such as drug delivery [14], cell culturing [15], or actuation [12], examples of much stiffer materials that exhibit such morphing mechanical behaviour are limited.…”

Nonlinear dynamics of self-oscillating polymer gels

“…Some polymer gels can swell or deswell, in a controlled manner, in response to external stimuli (e.g., pH [2], temperature [3], magnetism [4], electricity [5] and light [6]). Because of the distinctive characteristics of these gels (i.e., polymer gels with controlled response driven by external stimulations), they have been used for applications such as periodic precision devices (e.g., micropumps, smart control valves [7,8]) and environmental sensors (e.g., magneticfield sensor, pHresponsive device[9,10]).Besides external stimulation-controlled gels, self-oscillating polymer gels have also been developed which do not require external stimulations to rhythmically produce a dynamic response in volume (i.e., swelling and deswelling) [11,12], driven by Belousov-Zhabotinsky chemical reaction [13] (i.e., BZ gels). In BZ gels, catalyst ruthenium (i.e., Ru(bpy) 3 ) of the BZ reaction was chemically bundled on cross-linked polymer chains (Figure 1), and the BZ solution without the catalyst was dissolved into the polymer network.…”

Biomimetic Polymers for Chiral Resolution and Antifreeze Applications

“…Therefore, mimicking natural biopolymers encompasses many potential applications in medicine; 1-2 tissue engineering, [3][4][5][6][7][8] and drug delivery. [9][10][11][12][13][14] Among the variety of biomimetic research areas, the interactions of biopolymers with solids and crystals have attracted a great deal of attention in recent years. 15 Biomineralization [16][17][18] is the most prominent process in biological systems that incorporates biopolymers in the synthesis of a solid phase.…”