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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 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]

The article presents thermodynamic and kinetic surveys on the specific recognition and catalysis by molecularly imprinted polymer catalysts. Using p-nitrophenyl phosphate as templates and 1-allylimidazole as functional monomers, the imprinted material was prepared. The prepared polymer catalyst shows a highly specific recognition and catalysis toward the imprint species. Kinetic analysis indicates that this specific behavior, in nature, can be a result of a preferential promotion. The specific imprint leads to a larger hydrolysis rate in the imprint species than in its analogue. Thermodynamic study also implies that the molecular induction generating from the imprint to NPA is larger than to its analogue, which thus makes the polymer capable of specifically alluring the imprint species to bind. [ABSTRACT FROM AUTHOR]

Molecular imprinting is a promising technique for the preparation of polymers with predetermined selectivity and high affinity. Normally, based on the self-assembly of functional monomers and templates (i.e., imprint molecules), the imprinted polymers are produced by crosslinking polymerizations. The templates are subsequently removed from the polymer, leaving behind binding sites complementary to the imprint species in terms of the shape and the position of functional groups. Recognition of the polymer constitutes an induced molecular memory, which makes the binding sites capable of selectively recognizing the imprint species. This article presents a limited review on molecular self-assembly and the uses of these imprinted polymers in separation, sensors, and catalysis. Other aspects including related backgrounds are also discussed. [ABSTRACT FROM AUTHOR]