Self-healable polymer complex with a giant ionic thermoelectric effect.

In this study, we develop a stretchable/self-healable polymer, PEDOT:PAAMPSA:PA, with remarkably high ionic thermoelectric (iTE) properties: an ionic figure-of-merit of 12.3 at 70% relative humidity (RH). The iTE properties of PEDOT:PAAMPSA:PA are optimized by controlling the ion carrier concentration, ion diffusion coefficient, and Eastman entropy, and high stretchability and self-healing ability are achieved based on the dynamic interactions between the components. Moreover, the iTE properties are retained under repeated mechanical stress (30 cycles of self-healing and 50 cycles of stretching). An ionic thermoelectric capacitor (ITEC) device using PEDOT:PAAMPSA:PA achieves a maximum power output and energy density of 4.59 µW‧m-2 and 1.95 mJ‧m-2, respectively, at a load resistance of 10 KΩ, and a 9-pair ITEC module produces a voltage output of 0.37 V‧K-1 with a maximum power output of 0.21 µW‧m-2 and energy density of 0.35 mJ‧m-2 at 80% RH, demonstrating the potential for a self-powering source.

Self-Healable and Stretchable Ionic-Liquid-Based Thermoelectric Composites with High Ionic Seebeck Coefficient.

The advancement of wearable electronics, particularly self-powered wearable electronic devices, necessitates the development of efficient energy conversion technologies with flexible mechanical properties. Recently, ionic thermoelectric (TE) materials have attracted great attention because of their enormous thermopower, which can operate capacitors or supercapacitors by harvesting low-grade heat. This study presents self-healable, stretchable, and flexible ionic TE composites comprising an ionic liquid (IL), 1-ethyl-3-methylimidazolium trifluoromethanesulfonate (EMIM:OTf); a polymer matrix, poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP); and a fluoro-surfactant (FS). The self-healability of the IL-based composites originates from dynamic ion-dipole interactions between the IL, the PVDF-HFP, and the FS. The composites demonstrate excellent ionic TE properties with an ionic Seebeck coefficient (Si ) of ≈38.3 mV K-1 and an ionic figure of merit of ZTi  = 2.34 at 90% relative humidity, which are higher than the values reported for other IL-based TE materials. The IL-based ionic TE composites developed in this study can maintain excellent ionic TE properties under harsh conditions, including severe strain (75%) and multiple cutting-healing cycles.

Serial Comparison of Clinical Outcomes After Arthroscopic Capsular Release for Refractory Frozen Shoulder With and Without Diabetes.

PURPOSE: To compare serial clinical outcomes after arthroscopic treatment of refractory frozen shoulder with and without diabetes. METHODS: Seventeen patients with diabetic frozen shoulder (diabetes group) and 20 patients with idiopathic frozen shoulder (idiopathic group) were included. The mean follow-up period was 48.4 ± 15.8 months. Visual analog scale pain score; University of California, Los Angeles score; American Shoulder and Elbow Surgeons score; and range of motion were evaluated preoperatively; at 3, 6, and 12 months after surgery; and at the final follow-up examination. RESULTS: Both groups showed significant improvement in all clinical scores and range of motion during the serial follow-up periods (P < .001). There were no significant differences between the 2 groups in any of the assessed clinical scores, except the mean American Shoulder and Elbow Surgeons score in the diabetes group was significantly lower than that in the idiopathic group at 12 months after surgery (77.7 v 88.8, P = .025). In the diabetes group, mean forward flexion was significantly lower than that in the idiopathic group at 3 months (140.0° v 151.5°, P = .011) and 6 months (152.2° v 161.8°, P = .045) after surgery. Mean external rotation was significantly lower than that in the idiopathic group at 6 months after surgery (43.3° v 55.0°, P = .021). Mean internal rotation was significantly lower than that in the idiopathic group at 6 months (13.7 v 11.7, P = .006) and 12 months (12.2 v 9.9, P = .041) after surgery. There were no significant differences between the 2 groups in any assessed outcomes at the final follow-up examination. CONCLUSIONS: These results provide supportive evidence suggesting that the diabetes group had slower postoperative functional recovery until 12 months postoperatively, although arthroscopic capsular release for refractory frozen shoulder with and without diabetes yielded satisfactory clinical outcomes at the final follow-up examination. LEVEL OF EVIDENCE: Level III, retrospective comparative study.