title: Luminescent Poly(vinyl alcohol)/Carbon Quantum Dots Composites with Tunable Water-Induced Shape Memory Behavior in Different pH and Temperature Environments.
abstract: Luminescent water-induced shape memory polymer (SMP) composites with tunable shape recovery rate are developed by blending poly(vinyl alcohol) (PVA) and carbon quantum dots (CQDs). The oxygen and active hydrogen-rich CQDs can serve as extra physical cross-linking points in PVA via strong hydrogen bonding interaction, which largely improves the shape memory performances of PVA. At room temperature, water can successfully actuate the shape recovery of deformed PVA/CQDs composite. It is demonstrated that this water-induced shape recovery is mainly attributed to the plasticizing effect of water and its competitive hydrogen bonding. Furthermore, a quantitative bending test suggests that the shape recovery time of this water-induced SMP is tunable by altering the environmental pH value and temperature, and a relatively large shape recovery time window (from 20 to 200 s) can be achieved. In addition, the introduction of CQDs endows the PVA/CQDs SMP composites with excellent luminescent property, which makes the shape change of SMP visible under UV light. It should be noted that the mild stimulus condition and tunable shape recovery performances make the luminescent visible PVA/CQDs SMP feasible for diverse biological applications in smart medical devices, stimuli-responsive drug-release, and intelligent sensors in vivo and in vitro.
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering and ‡Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, PR China.
authors.forename: Guanghui
authors.initials: G
authors.lastname: Yang
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering and ‡Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, PR China.
authors.forename: Xuejuan
authors.identifier: http://orcid.org/0000-0003-2500-5169
authors.initials: X
authors.lastname: Wan
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering and ‡Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, PR China.
authors.forename: Yijin
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering and ‡Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, PR China.
authors.forename: Rui
authors.initials: R
authors.lastname: Li
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering and ‡Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, PR China.
authors.forename: Yikun
authors.initials: Y
authors.lastname: Su
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering and ‡Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, PR China.
authors.forename: Xierong
authors.initials: X
authors.lastname: Zeng
authors.affiliation: Shenzhen Key Laboratory of Polymer Science and Technology, College of Materials Science and Engineering and ‡Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University , Shenzhen 518060, PR China.
authors.forename: Jiaoning
authors.initials: J
authors.lastname: Tang
keywords: carbon quantum dots; luminescent polymer composites; shape memory; tunable shape recovery behavior; water environments