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The present endeavor is to develop a highly-intelligent catalytic reactor prototype which is able to autonomously adapt to the environment and provides an in-situ double-shift catalytic ability. By seeking inspiration from nature, this objective is achieved by developing a self-adaptive hydrogel catalytic reactor which held a catalytic trilaminar structure capable of reverse thermosensitive properties. With increasing temperatures, the catalytic tri-layers of this catalytic reactor would function in a sequential way (i.e., one negative temperature response layer, one support layer and one positive temperature response layer) and as a result, led to the single-tandem double-shift catalytic ability. This catalytic reactor individually presented single/tandem catalytic process at relatively low temperatures or high temperatures through the cooperative work of the three layers. In this way, this catalytic reactor showed the single-tandem controllable catalytic ability. The novel protocol not only provides a new solution to complicated catalytic processes but also inspires the further application of smart polymers in a broader spectrum of areas. [ABSTRACT FROM AUTHOR]

This study is aimed at booming intelligent catalysts, suggesting a bio-inspired polymer catalyst with catalytic substrate-sieving ability. By mimicking the hierarchical multi-level structures in biopolymers, this polymer catalyst was fabricated with metal nanoparticles and double "zipper" conformations individually made of polymeric hydrogen bonds and complexing interactions. Owing to the discrepant strength of both interactions against temperature, the double zipper conformations led to a hierarchical disruption of the two interactions and the stepwise disaggregation of the polymeric networks and as a result the substrate-sieving ability. This catalyst didn't present effective catalysis at low temperatures because of the blocked networks. With the increasing temperatures, this catalyst would first present catalysis towards small molecules of substrate and then further towards bigger molecules of substrate, by virtue of the hierarchical disruption of the weaker hydrogen bonds and the stronger complexing interactions. In this way, this catalyst assumed the substrate-sieving ability. The protocol of this catalyst suggests a prospect to modulate the catalytic proceedings, particularly for complicated processes. [ABSTRACT FROM AUTHOR]

This study is aimed at booming intelligent polymers and their applications in catalysis, presenting an intelligent polymer catalyst with photo-mediated catalytic ability. This catalyst was fabricated with polymeric 2-acrylamide-2-methylpropylsulfonic acid (acidic moieties capable of catalytic hydrolysis) and photo-sensitive acrylamide-azobenzene prepared from the synthesis of 4-aminoazobenzene with acryloyl chloride. Under the radiation of ultraviolet light, this catalyst would undergo a change of cis/trans-conformation of azobenzene, causing alterable accessibility to the internal catalytic sites and as a result mediated catalytic ability. This catalyst presented significant catalytic ability at ambient conditions due to the trans-conformation of azobenzene which endorsed accessibility to the internal catalytic sites. Conversely, this catalyst showed limited catalytic ability under ultraviolet light, in response to the isomerization of the cis-conformation of azobenzene which inhibited the accessibility. In this way, this catalyst showed the photo-mediated catalytic ability. The suggestion of this polymer catalyst provides a prospect to optically modulate the catalytic proceedings, particularly for complicated processes. [ABSTRACT FROM AUTHOR]

A smart catalytic reactor capable of simple/tandem-commutative catalytic ability was reported here. By borrowing the natural soft morphology and segregated zones in biosystems, this reactor was constructed with polymeric bilayer composites where each constituted a catalytic zone. The combination of the two catalytic zones with a catalytically-coupled process would dictate the reactor sequential catalytic behaviors and accordingly simple/tandem-commutative catalytic ability. To that end, one of the layers in this reactor was fabricated with acidic architectures capable of catalytic hydrolysis whereas the other layer was made of a thermo-sensitive antibody-like imprinted hydrogel which acted as a switch to provide access for the succeeding reaction. In this way, this reactor demonstrated the simple/tandem-commutative catalytic ability. This suggested design shares a promising prospect with developing functional catalysts and programmable catalytic processes. [ABSTRACT FROM AUTHOR]

This study is aimed at the present challenge in self-controlled catalysts, addressing how to furnish the catalysts with cascade/non-cascade-switchable catalytic ability. By borrowing the "soft" properties and autonomous ability from nature, this objective was met by reporting an artificial polymer reactor that was composite of tri-layer architectures made of two inversely-thermosensitive outward layers and a non-responsive middle layer. With the middle layer containing catalytic metal nanoparticles, the two thermosensitive outward layers consisted separately of a negatively-temperature responsive polymer and a positively-temperature responsive composite. The opposite responsiveness at the two thermosensitive outward layers induced convex/flat/concave-switchable shapes in this reactor, leading to cascade/non-cascade-alterable substrate channeling to the reactive middle layer. In this way, this polymer reactor led to the occurrence of cascade/non-cascade-switchable catalytic ability. This design shares a promising prospect with the struggling field of self-controlled catalysts, which allows opportunities to finely control catalytic processes. [ABSTRACT FROM AUTHOR]

A large number of species in nature demonstrate switchable responsiveness to external stimuli, which is essential for their adaptation to the changing environment. Inspired by the responsive properties in nature, researchers have made significant progress in the field of synthetic stimuli-responsive materials over the years, particularly in the field of smart polymer catalysts which are able to control the catalytic processes. Here, we review these bio-inspired polymer materials and their applications in self-controlled catalytic processes. Other issues involved in developing these bio-inspired polymer materials including the origin, mechanisms, switchable behaviors and merits are also discussed. [ABSTRACT FROM AUTHOR]

This study is aimed at the present challenge in tandem catalysts, addressing how to endow the catalysts with self‐controlled tandem catalytic‐ability. By borrowing the predation strategy from sundew, the objective was originally met by reporting a smart tandem catalyst which can self‐control the tandem catalytic behavior by catching, decomposing and assimilating the engaging molecules (such as 4‐nitrophenyl acetate). This catalyst was made of a unique leaf containing two functional layers where each may be responsible for one coupled process. The first layer in this catalyst was fabricated with a zipper‐like reactive polymer capable of opening and closing, which allowed the catalyst to catch and decompose 4‐nitrophenyl acetate. The second layer in this catalyst allowed, however, further access to assimilate the decomposed substrate (i. e., 4‐nitrophenol), made of an antibody‐like polymer and encapsulated metal nanoparticles. In this way, the use of this catalyst led to the occurrence of the self‐controlled tandem catalytic‐ability. This novel design suggests a new protocol for developing smart tandem catalysts, which opens new opportunities for controlled tandem catalytic processes. Copying Nature: Inspired by the predation strategy in sundews, this study presents the first case of smart tandem catalysts which can self‐control the tandem catalytic behavior by catching, decomposing and assimilating the engaging molecules (such as 4‐nitrophenyl acetate). This catalyst was fabricated with a unique leaf made of two functional layers where each may be responsible for one coupled process. This novel design opens new opportunities for controlled tandem catalytic processes. [ABSTRACT FROM AUTHOR]

This study was aimed at addressing the present challenge of cascade reactions, namely, how to furnish the catalysts with desired and hierarchical catalytic ability. This issue was addressed by constructing a cascade-reaction nanoreactor made of a bifunctional molecularly imprinted polymer containing acidic catalytic sites and Pt nanoparticles. The acidic catalytic sites within the imprinted polymer allowed one specified reaction, whereas the encapsulated Pt nanoparticles were responsible for another coupled reaction. To that end, the unique imprinted polymer was fabricated by using two well-coupled templates, that is, 4-nitrophenyl acetate and 4-nitrophenol. The catalytic hydrolysis of the former compound at the acidic catalytic sites led to the formation of the latter compound, which was further reduced by the encapsulated Pt nanoparticles to 4-aminophenol. Therefore, this nanoreactor demonstrated a catalytic-cascade ability. This protocol opens up the opportunity to develop functional catalysts for complicated chemical processes. [ABSTRACT FROM AUTHOR]

How to furnish catalysts with switchable catalytic ability is a challenge in self-controlled catalysis. This issue was addressed by constructing a unique polymer nanoreactor containing 'mobility-recalling' switchable domains that acted as a molecular switch for providing access to the encapsulated metal nanoparticles. This polymer reactor revealed poor reactivity at relatively low temperatures because of the 'frozen' molecular chains in the switchable domains inhibiting the access of substrate to the encapsulated metal nanoparticles (i.e., catalytic 'off' status). In contrast, the polymer reactor demonstrated significant reactivity at relatively high temperatures, resulting from the dramatically increased mobility of the molecular chains, which allowed access to the encapsulated nickel nanoparticles (i.e., catalytic 'on' status). Switching between the catalytic off and on statuses could be repeated owing to the recallable mobility of molecular chains in the switchable domains. This protocol opens up the opportunity to develop smart nanoreactors for controlled chemical processes. [ABSTRACT FROM AUTHOR]

In this work, the molecular imprinted polymers were synthesized with the low monomer concentrations for dibutyl phthalate (DBP). The polymers were prepared over carboxyl-modified silica nanoparticle, which used methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker agent and azoisobutyronitrile as the initiator in the process of preparation. Various measures were used to characterize the structure and morphology in order to get the optimal polymer. The characterization results show that the optimal polymer has suitable features for further adsorption process. And adsorption capacity experiments were evaluated to analyze its adsorption performance, through adsorption isotherms/kinetics, selectivity adsorption and desorption and regeneration experiments. These results showed that the molecular imprinted polymers had a short equilibrium time about 60 min and high stability with 88% after six cycles. Furthermore, the molecular imprinted polymers were successfully applied to remove dibutyl phthalate. The concentration range was 5.0–30.0 μmol L −1 , and the limit of detection was 0.06 μmol L −1 in tap water samples. [ABSTRACT FROM AUTHOR]