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In this chapter, strategies for fabricating thermo-/pH-dual-responsive hydrogels with rapid response properties are introduced systematically. The types of hydrogels include thermo-/pH-dual-responsive anionic poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAM-co-AAc)) hydrogels and microgels and cationic poly(N-isopropylacrylamide-co-N,N’-dimethylamino ethyl methacrylate) (poly(NIPAM-co-DMAEMA)) hydrogels.

In this chapter, the design, fabrication, and performance of the pH-responsive composite membrane system and core-shell microcapsule systems with improved controlled-release properties are introduced. The pH-responsive composite membrane system is featured with a high responsive release rate, which is composed of a porous membrane with linear-grafted positively pH-responsive polymer gates acting as functional valves, and a cross-linked negatively pH-responsive hydrogel inside the reservoir working as a functional pump. Two kinds of monodisperse core-shell microcapsule systems with acid-triggered burst release properties are developed by microfluidic approach. These pH-responsive systems provide new modes for smart controlled-release systems, which are highly attractive for drug delivery systems, chemical carriers, sensors, and so on.

In this chapter, the design, fabrication, and performance of the ion-recognizable functional microcapsules with crown ether as ion-recognition receptor and poly(N-isopropylacrylamide) (PNIPAM) as actuator are introduced. The microcapsules with different capsule structures and/or different crown ether receptors are developed for different purposes. For the porous microcapsule with ion-recognizable smart gates using 18-crown-6 as the ion receptor, the functional gates in the pores can close by recognizing Ba2+. For the microcapsule with ion-recognizable cross-linked hydrogel membrane using 15-crown-5 as the ion receptor, the microcapsule shrinks isothermally by recognizing K+. For the microcapsule with ion-recognizable cross-linked hydrogel membrane using 18-crown-6 as the ion receptor, the microcapsule swells isothermally by recognizing Ba2+ or Pb2+. These ion-recognizable microcapsules provide new modes for smart controlled-release systems, which are highly attractive for drug delivery systems, chemical carriers, sensors, and so on.

In this chapter, three glucose-responsive systems with different structures for controlled release, including flat membranes with gates in the pores, hollow microcapsules with gates in the porous shell, and hollow microcapsules with a hydrogel shell, are introduced.

In this chapter, the design, fabrication, and performance of smart functional membranes with molecular-recognizable properties are introduced. The membranes are prepared by suspending β-cyclodextrin (CD) host molecules onto the freely mobile ends of thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) chains grafted in the membrane pores. By virtue of the interaction between the lower critical solution temperature (LCST) of PNIPAM chains and association constant of CD toward guest molecules, the membranes based on PNIPAM and CD are demonstrated to chiral separate enantiomers, adsorb/desorb guest molecules, and controlled-release model drug molecules. During the chiral separation, the PNG-ECD-grafted membranes separate D,L-tryptophan enantiomers with a high selectivity and regenerate with a high decomplexation ratio by simply changing the operation temperature. By simply adjusting the operation temperature, the membranes adsorb guest molecules at lower temperature and desorb at higher temperature. Moreover, the membranes with the same functional gate are featured with triple stimuli-responsive gating functions and release the model drug molecules in a controlled manner. The as-prepared membranes based on PNIPAM and CD are highly attractive for chiral separation, affinity separation, and controlled-release systems responding to the environmental temperature and guest molecules.

This research takes the theory of brand experience as the guidance, uses the brand experience evaluation as its method and aims the service design as its target. And the research is to search for the new theory and model of promoting brand image. We have designed creatively the semantic analysis scale of experience evaluation of Wuxi fruit brand Yangshan Shuimi Peaches. Psychologically, we evaluated 3 types of the packages of PeachWell Brand: A (the original package), B (new package) and C (new package). After that, we collected the CSI (Customer Satisfaction Index) data, which showed the difference: B>C>A. Demographic samples divided by different means all had their own different requires of brand packages. These CSI data showed us that the new package B and C made more contributions to upgrading the brand. According to the result analyses of the empirical research on brand experience, we bring up the detailed service design plans and positive advices of promoting the brand image.

Polyphenols such as tannic acid (TA) and ethyl gallate (EG) are important substances in food and medical, biological, and chemical fields and are used widely. In this chapter, polyphenol-induced phase transition behaviors of thermo-responsive PNIPAM hydrogels are introduced. Because microgels can respond much faster than macroscale hydrogels to environmental stimuli due to their small dimensions, PNIPAM hydrogel microgels rather than macroscale hydrogels are used to study the phase transition behaviors. Both equilibrium and dynamic phase transition behaviors of monodisperse PNIPAM microgels induced by TA and those of core-shell microcapsules with a PNIPAM shell and a colored oil core induced by EG are introduced.

The flow characteristics and kinetic characteristics during the phase transition may directly affect the performance of thermo-responsive microspheres in many applications. In this chapter, to probe into the flow and aggregation behaviors of thermo-responsive microspheres in microchannel during the phase transition, the flow characteristics of monodisperse poly(N-isopropylacrylamide) (PNIPAM) microspheres in microchannel with local heating are introduced systematically. Furthermore, the effects of microchannel surface wettability and roughness on the flow behaviors of thermo-responsive microspheres during the phase transition are also introduced. The phenomena show that the microspheres can aggregate together during the phase transition and stop automatically at a desired position in the microchannel by local heating if designed properly, which is what the targeting drug delivery systems expected.

In this chapter, the design, fabrication, and performance of functional membranes/systems with thermo-responsive hydrogel gates are introduced. The thermo-responsive polymeric hydrogel gates are either grafted or filled into the membrane pores. The response temperature of the prepared membranes can be regulated by the introduction of hydrophilic or hydrophobic monomers in the comonomer solution. The thermo-responsive gating characteristics of membranes are affected by the grafting degree, length, and density of polymeric gates as well as preparation temperature, etc. In addition, the membranes exhibit a satisfactory thermo-responsive controlled-release characteristics and affinity adsorption/desorption behavior. The results in this study provide valuable guidance for designing, fabricating, and operating thermo-responsive gating membranes with desirable performances.

In this chapter, the design, fabrication, and performance of the ion-recognizable smart hydrogels with crown ether as ion-recognition receptor and thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) as actuator are introduced. Smart responsive hydrogels capable of recognizing heavy metal ions or potassium ion are fabricated with different crown ethers for different purposes. Smart hydrogels with 18-crown-6 as ion-recognition receptor could respond to Pb2+ and Ba2+ due to the formation of 1:1 (ligand to ion) “host-guest” complex; smart hydrogels with 15-crown-5 as ion-recognition receptor could respond to K+ due to the formation of 2:1 (ligand to ion) sandwich “host-guest” complex.

In this chapter, the design, fabrication, and performance of smart functional membranes with alcohol-responsive characteristics are introduced. The membranes with alcohol-responsive characteristics are either flat membrane grafted with smart gates or core-shell microcapsule membrane composed of smart materials. The critical alcohol response concentrations of these membranes are regulated by simply adjusting the lower critical solution temperature (LCST) of the grafted polymeric gates in water or controlling the environmental temperature. The PNIPAM-grafted membranes with controllable critical ethanol response concentrations can be efficiently applied to various practical conditions, where the transmembrane permeability needs to be manipulated by the environmental ethanol concentration and operation temperature. The core-shell PNIPAM microcapsule membranes can function as both sensors and actuators by converting alcohol concentration variation into mechanic forces. The results in this study provide potential applications in more efficient fermentation process and may also provide opportunities in cargo delivery in alcoholic environments.

In this chapter, a new type of glucose-responsive hydrogel with rapid response to blood glucose concentration change at physiological temperature is introduced. The hydrogel contains 3-acrylamidophenylboronic acid (AAPBA) with phenylboronic acid (PBA) groups as glucose sensors and thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) as actuators. The response rate of the hydrogel to the change of environmental glucose concentration is significantly enhanced by introducing grafted poly(NIPAM-co-AAPBA) (PNA) side chains onto cross-linked PNA networks for the first time. The synthesized comb-type PNA hydrogels show satisfactory equilibrium glucose-responsive properties. Meanwhile, the hydrogels exhibit much faster response rate to glucose concentration change than normal type of cross-linked PNA hydrogels at physiological temperature. Such glucose-responsive hydrogels with rapid response rate are highly attractive for developing glucose-responsive sensors and self-regulated drug delivery systems.

In this chapter, the fabrication and performance of molecular-recognizable smart hydrogels based on poly(N-isopropylacrylamide) (PNIPAM) and β-cyclodextrins (CD) are introduced. The length of the monosubstituted carbon chain of modified CD as well as the categories and concentrations of guest molecules has great effect on the molecular-recognition-induced phase transition of PNIPAM polymers with pendent CD moieties. The increase in the hydrophobicity of hydrogel network leads to a considerable increase in affinity behavior toward guest molecules. Meanwhile, the association site is demonstrated to shift from original β-cyclodextrin at low temperatures to a combination of β-cyclodextrin and the PNIPAM network at high temperatures. The synthesized PNIPAM polymers and hydrogels with pendent CD moieties have the potential to be applied to the engineering of molecular-recognition sensors and switches and also the development of temperature-controlled affinity separation systems.

Monodispersity is very important for the stimuli-responsive microspheres to improve their performance in various applications. In this chapter, several strategies including surfactant-free emulsion polymerization, membrane emulsification, and microfluidics are introduced to prepare monodisperse thermo-responsive microgels. The type of microgels includes both negatively and positively submicron-sized monodisperse thermo-responsive core-shell hydrogel microspheres and micro-sized monodisperse thermo-responsive microspheres and microcapsules.

In this chapter, the design, fabrication, and property of functional microcapsules with thermo-responsive hydrogel shells are introduced. The as-designed thermo-responsive microcapsules can be microcapsules with membranes grafted by poly(N-isopropylacrylamide) (PNIPAM) chains or interspersed with PNIPAM microgels as gates, or microcapsules with whole thermo-responsive PNIPAM membranes. Both Shirasu porous glass (SPG) membrane emulsification and capillary microfluidic emulsification are employed to generate the monodisperse emulsions with controllable size, and subsequently the emulsions as template are polymerized into microcapsules. The prepared thermo-responsive microcapsules with membranes grafted or embedded PNIPAM gates display satisfactory reversible and reproducible thermo-responsive controlled-release characteristics, while those microcapsules with whole PNIPAM membranes exhibit prompt and complete temperature-triggered bursting-release characteristics. These thermo-responsive microcapsules are highly attractive for various promising applications, such as site-targeting drug delivery system, controlled release of chemicals, microreactors, biomedical and/or chemical sensors, immobilization of cells and enzymes, and encapsulation of foods and cosmetics.

In this chapter, the structure-function relationship of thermo-responsive hydrogel materials with various internal microstructures is introduced. The fabrication, microstructure control, and performance of thermo-responsive hydrogels are described. The relationships between the internal microstructures of the thermo-responsive hydrogels and their thermo-responsive and mechanical properties, such as equilibrium thermo-responsive phase transition, dynamic thermo-responsive phase transition, thermo-responsive controlled-release characteristics, and mechanical strength, are discussed systematically.

In this chapter, the design, fabrication and performance of glucose-responsive gating membranes with grafted poly(acrylic acid) (PAAC) gates and covalently bound glucose oxidase (GOD) enzymes, including both flat membranes and microcapsule membranes, are introduced. The linear grafted PAAC chains in the membrane pores act as the pH-responsive gates or actuators, and the immobilized GOD acts as the glucose sensor and catalyzer because it is sensitive to glucose and catalyzes the glucose conversion to gluconic acid. The pore size and permeability control of the glucose-responsive gating membranes will be described systematically. The glucose-responsivity of the solute diffusional permeability through the prepared flat membranes is heavily dependent on the PAAC grafting yield, because the pH-responsive change of pore size governed the glucose-responsive diffusional permeability. It is very important to design a proper grafting yield to obtain an ideal gating response. The prepared PAAC-grafted and GOD-immobilized microcapsule membranes demonstrate reversible glucose-responsive release characteristics.

In this chapter, the development trend of smart membrane materials and systems and the potential applications of smart membranes are introduced and discussed briefly.

Based on the quasi-sliding mode theory, a novel fixed-frequency nonlinear controller for single-inductor dual-output (SIDO) buck converter in pseudo-continuous conduction mode (PCCM) is presented in this paper. The main advantage of this nonlinear controller is that both small and large signal variations around the operating point are taken into account, which results in better transient response. To validate the feasibility of the scheme, a prototype of a SIDO buck converter with two outputs of 1.8 V and 3.3 V is developed in MATLAB SIMULINK. Simulation results show that the transient response of the SIDO buck converter with quasi-sliding mode controller is only 75 μs, contrasting to 900 μs with voltage feedback controller and 550 μs with peak current controller, when the load current of one channel changes from 100 mA to 10 mA.

In this chapter, dual-/multi-stimuli-responsive smart membranes are described for more applicable purposes. Dual stimuli-responsive microcapsules with a superparamagnetic porous membrane and thermo-responsive gates, superparamagnetic and thermo-responsive microcapsules with hydrogel membranes, dual thermo-responsive and molecular-recognizable membranes and multi-stimuli-responsive membrane gates with hierarchical structures are introduced. The content in this chapter provides a more open mind for designing and fabricating stimuli-responsive smart membranes.

In this chapter, the design, fabrication and performance of molecular-recognizable smart membranes with either β-cyclodextrin (CD) or crown ether as molecular recognizing receptor and with poly(N-isopropylacrylamide) (PNIPAM) as actuator are introduced. Both flat and microcapsule membranes with molecular-recognizable smart gates and microcapsules with molecular-recognizable smart hydrogel membranes are developed for different purposes. For the membranes with molecular-recognizable smart gates, the gates in the membrane pores can open or close by recognizing specific molecules or ions; for the microcapsules with crosslinked hydrogel membranes, the membranes swell or shrink isothermally by recognizing specific molecules or ions.

In this chapter, the design, fabrication and performance of smart microcapsules with pH-responsive chitosan hydrogel membranes are introduced. The pH-responsive microcapsules with crosslinked chitosan membranes are fabricated with a microfluidic approach using monodisperse O/W/O emulsions as templates to form a crosslinked chitosan membrane at the inner O/W interface via interfacial crosslinking reaction between chitosan and terephthalaldehyde. The chitosan microcapsule membranes show acid-induced pH-responsive swelling and decomposing behavior. Such monodisperse polysaccharide microcapsules with pH-responsive chitosan hydrogel membranes could serve as promising candidates for pH-responsive drug delivery systems.

In this chapter, the design, fabrication and performance of a composite pH-responsive membrane system for improved controlled-release, which is composed of a porous membrane with linear-grafted positively pH-responsive polymeric gates acting as functional valves, and a crosslinked negatively pH-responsive hydrogel inside the reservoir working as a functional pumping element, are introduced. The composite membrane system is featured with a large responsive release rate that goes effectively beyond the limit of concentration-driven diffusion due to the pumping effects of the negatively responsive hydrogel inside the reservoir. The system provides a new mode for pH-responsive smart controlled-release systems, which is highly attractive for drug delivery systems, chemical carriers, and sensors and so on.

On the basis of the knowledge of thermo-responsive gating membranes, introduced in Chapter 2, the design, fabrication and performance of smart microcapsules with thermo-responsive gating membranes for controlled release are described in this chapter. Firstly, the design of smart microcapsules with thermo-responsive gating membranes is introduced. Next, the fabrication, microstructure control and controlled-release performance of thermo-responsive microcapsules with a porous membrane and PNIPAM gates are described systematically. Then, the fabrication and microstructure control of small-sized monodispersed thermo-responsive microcapsules are introduced.

In this chapter, the design, fabrication and performance of thermo-responsive membranes for chiral resolution with a high performance are introduced. The membrane is designed with both chiral selectivity based on molecular recognition of beta-cyclodextrin (β-CD) and thermo-sensitivity based on phase transition of PNIPAM. Linear PNIPAM chains are grafted onto porous Nylon6 membrane substrates by using the plasma-graft pore-filling polymerization method, acting as micro-environmental adjustors for β-CD molecules. β-CD moieties are introduced into the linear PNIPAM chains by the chemical grafting polymerization method, acting as chiral selectors. The phase transition of grafted PNIPAM chains affects the micro-environment of β-CD molecules and then the association between β-CD and guest molecules. The chiral selectivity of the prepared thermo-responsive membranes in chiral resolution operated at a temperature below the LCST of PNIPAM is higher than that of membranes with no thermo-sensitivity, while the decomplexation ratio of enantiomer-loaded thermo-responsive membranes in decomplexation operated at a temperature above the LCST is much higher than that of membranes with no thermo-sensitivity. By simply changing the operating temperature, high selective chiral resolution and efficient membrane regeneration can be achieved.

The influence of handset modeling characteristics on people's image cognition was studied based on the theory of Kansei engineering and using questionnaire and statistical analysis. According to the results-designers can get the corresponding handset modeling characteristics which most fit the ideal Kansei image chosen by the consumers. It's a new way of directing the development of new products' modeling design.

As there are many cases in which environmental temperature fluctuations occur naturally, and in which the environmental temperature stimuli can be easily designed and artificially controlled, much attention has recently focused on thermoresponsive smart membrane materials and systems. In this chapter, the emphasis is focused on the design, microstructures and performances of thermo-responsive gating membranes, which are also valuable for designing and fabricating other stimuli-responsive gating membranes. Firstly, the design of thermo-responsive gating membranes is introduced. Secondly, the formation and microstructures of grafted PNIPAM polymers in pore-filling type thermo-responsive gating membranes, fabricated by both plasma-induced grafting polymerization and atom-transfer radical polymerization, are discussed. Then, effects of the grafting yield, the length and density of grafted chains on thermo-responsive gating characteristics of pore-filling type PNIPAM-grafted membranes are discussed systematically. Next, the gating characteristics of thermo-responsive membranes with grafted linear and crosslinked PNIPAM gates and the thermo-responsive wettability characteristics of PNIPAM-grafted membranes are described. Finally, thermo-responsive gating membranes with controllable response temperature and membranes with negatively thermoresponsive gating characteristics are introduced.

Besides smart microcapsules with porous substrates and stimuli-responsive gates as described in Chapter 3, smart microcapsules can also be designed with the whole membranes consisting of stimuli-responsive smart hydrogels. In this chapter, the design, fabrication and performance of monodisperse smart microcapsules with thermo-responsive hydrogel membranes are introduced. For different application purposes, smart microcapsules with thermo-responsive PNIPAM hydrogel membranes are designed and fabricated with either water-in-oil (W/O) single emulsions, oil-in-water-in-oil (O/W/O) double emulsions, or water-in-oil-in-water-in-oil (W/O/W/O) triple emulsions as synthesis templates. The thermo-responsive PNIPAM hollow microcapsules, prepared with W/O single emulsions as templates, show reversible thermo-responsive swelling/shrinking volume phase transition behavior as the temperature changes across the lower critical solution temperature (LCST). The thermo-responsive PNIPAM hollow microcapsules, prepared with O/W/O double emulsions and W/O/W/O triple emulsions as templates, demonstrate thermo-induced burst squirting property for controlled release.

In this chapter, the design, fabrication and performance of thermo-responsive adsorption/desorption membranes for affinity separation are introduced. Firstly, the design of fabrication of thermo-responsive affinity membranes with nanostructured pores and grafted PNIPAM surface layer for hydrophobic adsorption are described. The membrane shows efficient “adsorbing at a temperature above the LCST-desorbing at a temperature below the LCST” performance for bovine serum albumin molecules. Then a temperature-dependent molecular-recognizable membrane with both grafted PNIPAM chains and immobilized β-CD moieties for affinity separation is introduced. Contrariwise to the first kind of membrane, this membrane demonstrates effective “adsorbing at a temperature below the LCST-desorbing at a temperature above the LCST” performance for guest molecules.