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A self-switchable polymer reactor with a hyperbranched structure for controlled catalytic chemistry processes is reported. This polymer reactor was made of silver nanoparticles and a polymer carrier consisting of hyperbranched polyethylenimine and hydroxyethyl acrylate that behaved as thermally switchable domains. Below the transfer temperature, relatively strong catalytic reactivity was demonstrated due to the leading role of hydrophilic groups in the switchable domains, which opened access to the substrate for the packaged silver nanoparticles. In contrast, it showed weak catalysis at relatively high temperatures, reducing from the significantly increased hydrophobicity in the switchable domains. In this way, the polymer reactor displays controllable, tunable, catalytic activity based on this approach. This novel design opens up the opportunity to develop intelligent polymer reactors for controlled catalytic 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]