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[Display omitted] • First discovery, locally π-π conjugated polyimide in TGIC enhances loss capacity. • Increasing the number of conjugated benzenes amplifies the dielectric loss. • Right amount of PPI-D highlights the comprehensive performance for PPI-D/TGIC. • PPI-D/TGIC-0.5 has the best RL min (-15.6 dB, 16.4 GHz) and EAB (3.44 GHz, 6.0 mm). • PPI-D/TGIC-0.5 has elastic modulus (1065.4 MPa) and thermal stability (295 ℃). Creatively, endowing the resin matrix with microwave absorption performance is an effective strategy to improve the comprehensive performance for microwave absorption materials and eliminate the contradiction between matrix and absorbent. Herein, a high polar epoxy resin that triglycidyl isocyanurate (TGIC) is chemically cross-linked with locally π-π conjugated polyimides (PI) to create a novel absorbing resin matrix designed for special responses in X and Ku bands. By comparing the dielectric properties and microwave absorption performance of PBI-D/TGIC (containing benzene), PNI-D/TGIC (containing naphthalene) and PPI-D/TGIC (containing perylene), their dielectric polarization loss and microwave absorption responses will be enhanced with the increase of conjugated benzene number, which is ascribed to the enhanced π-π conjugated polarization and the instantaneously reduced resistance stimulated by electromagnetic waves (EMWs). Simultaneously, the addition of an appropriate amount of PPI-D significantly enhances the microwave absorption performance, mechanical strength, and thermal stability of TGIC-based resins. When the mixing mass ratio of PPI-D to TGIC is 1:4, the obtained PPI-D/TGIC-0.5 (PPI-D: 25.23 wt%) possesses the best minimum reflection loss (RL min) as −15.6 dB (16.4 GHz, 3.0 mm) and −8.6 dB (8.2 GHz, 4.0 mm), which is three times higher than the RL min of TGIC. Especially, the effective absorption bandwidth (EAB < -10 dB) of PPI-D/TGIC-0.5 resin can reach up to 3.44 GHz (6.0 mm) and 2.88 GHz (3.0 mm), breaking the limitations of conventional resins. Additionally, PPI-D/TGIC-0.5 resin exhibits excellent compression performance (37 MPa), elastic modulus (1065.4 MPa) and thermal stability (T 10wt.% =295 ℃). PPI-D/TGIC-0.5 resin is a strong candidate for the ideal absorbing resin matrix and holds significant potential in the applications for microwave absorption materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hydrogel with ROS/glucose and exosomes-released properties was developed. • The hydrogel could reduce ROS and inflammatory response by repairing the ETC. • The hydrogel offers a localized exosomes dual-response release strategy. With numerous attempts at chronic wound healing in recent years, significant challenges pertaining to diabetic wound healing have arisen. These challenges result from excessive oxidative stress, vulnerability to bacterial infection, and persistent inflammation during the healing process. In response to the lack of a specific exosomes-sustained release system tailored for diabetic wounds, a reactive oxygen species (ROS)/glucose dual-responsive stimulated exosomes-released self-healing antibacterial antioxidant conductive multifunctional hydrogel has been developed, utilizing a simplistic "one-pot" method. This innovative hydrogel is constructed from a harmonious blend of polydopamine grafted MXene (PMX), chlorogenic acid (CA), L-ascorbate-2-phosphate trisodium slat (L), and adipose-derived stem cells (ADSCs) derived exosomes (E) with phenylboronic acid modified flaxseed gum (LG-PBA), chemically cross-linked with polyvinyl alcohol (PVA) to generate dynamic phenylboronate ester bond, to obtain P-LP-PMX-CA-L@E hydrogel. It was further demonstrated that the ROS/glucose-responsive exosomes-released P-LP-PMX-CA-L@E hydrogel integrated system could reduce ROS and inflammatory response by repairing the electron transfer chain, thereby facilitating skin damage repair in a mouse type I diabetic model. In conclusion, the multifunctional P-LP-PMX-CA-L@E hydrogel, endowed with stimuli-responsive exosomes release capability, exhibits a promoting effect on the healing of chronic diabetic wounds and offers a localized exosomes dual-response release strategy for the treatment of type I diabetic wounds. [ABSTRACT FROM AUTHOR]