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Shape memory polymers (SMPs), as a class of intelligent materials, have shown great potential in biomedical and robotic fields. Although efforts have been made to design and fabricate SMPs in the past decades, most of the SMPs are not suitable for use in the human body due to their unpleasant triggering conditions. Furthermore, it is of great importance to diversify the shape memory effect (SME) of SMPs to extend their applications. In this work, through thiol-ene chemistry, SMPs based on random cross-linked hydrophobic polytetrahydrofuran (PTHF) and hydrophilic poly­(ethylene glycol) (PEG) oligomers were facilely fabricated. These SMPs showed a body temperature-triggered two-way SME with a reversible strain of up to 25.2%. Besides, the SMPs exhibited a good body temperature- and water-triggered one-way triple-SME. These features bestowed the polymers with a bright future in biomedical applications. Polymer P60-G40 was applied as a new type of esophageal stent, and the in vitro assessment showed that the stent was adjustable, self-expandable, and had the ability to release drugs, which were attributed to the one-way triple-SME and two-way SME.

Shape memory polymers (SMPs) with the permanent shape reconfiguration capability have received much research interest because they are capable of diversified tasks and the ability to work in conditions that required complex geometry. However, most of such SMPs are thermally triggered, which limits their applications. Inspired by reversible mussel adhesive protein chemistry, NIR light‐triggered SMPs with the permanent shape reconfiguration capability are prepared. The polymer networks are constructed using biocompatible polyethylene glycol, which is crosslinked based on catechol–Fe3+ coordination. The polymer networks have a uniform network structure and exhibit a considerable one‐way shape memory effect (1W‐SME) as well as a good two‐way shape memory effect (2W‐SME) under stress conditions. Taking advantage of the dynamic nature of the catechol–Fe3+ coordination, the permanent shape of the polymers could be reconfigured. Moreover, the catechol–Fe3+ complexes have a broad absorption in the NIR window, which bestows the polymers with excellent NIR light‐triggered SME. Further, the great potential of the obtained polymers in biomedical and electronic applications is presented. Owing to the NIR‐triggered 1W‐SME and the permanent shape reconfiguration capability, the polymer could be used as a personalizing vascular stent. Additionally, the polymer could be applied in light‐driven switches based on the NIR light‐triggered 2W‐SME.

Most reported microneedle patches still suffer from a complicated preparation process and insufficient loading capacity for the glucose‐responsive delivery system. Herein, based on the reversibility of the boronate ester bond, a novel gel was formed by mixing phenylboronic acid grafted sodium hyaluronate and polyvinyl alcohol. The insulin‐loaded microneedle patch could be directly obtained by simply blending high‐dose insulin and gel into the mold. The introduction of cellulose nanofiber was also found to be in favor of mechanical strength. The glucose responsibility could be achieved when the boronate ester bond was broken by glucose, leading to the change of crosslinking density and further controlling insulin release. In the hypoglycemic experiment of diabetic rats, the microneedle patches could effectively puncture the skin and maintain normal blood glucose levels for an extended period. The facile preparation process and high loading capacity give this microneedle patch a great chance in mass production.

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The rise of miniaturized, integrated, and functional electronic devices has intensified the need for heat dissipation. To address this challenge, it is necessary to develop novel thermally conductive polymer composites as packaging materials. In this paper, a number of factors for the construction and design of thermally conductive polymers are concluded. Special attention is focused on the analysis and comparison of the thermally conductive composites prepared by various fillers or strategies to provide guidelines and references for future design of composite materials. The current commonly used preparation strategies of thermally conductive polymer are summarized, such as using a variety of fillers, vacuum filtration, template method, and so on. The challenges of thermally conductive polymer composites are finally sketched. This review can inspire the design of polymer composites with brilliant thermal conductivity.

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