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Although the elastocaloric effect was found in natural rubber as early as 160 years ago, commercial elastocaloric refrigeration based on polymer elastomers has stagnated owing to their deficient elastocaloric effects and large extension ratios. Herein, we demonstrate that polymer elastomers with uniform molecular chain-lengths exhibit enormous elastocaloric effects through reversible conformational changes. An adiabatic temperature change of −15.3 K and an isothermal entropy change of 145 J kg−1 K−1, obtained from poly(styrene-b-ethylene-co-butylene-b-styrene) near room temperature, exceed those of previously reported elastocaloric polymers. A rotary-motion cooling device is tailored to high-strains characteristics of rubbers, which effectively discharges the cooling energy of polymer elastomers. Our work provides a strategy for the enhancement of elastocaloric effects and could promote the commercialization of solid-state cooling devices based on polymer elastomers.

Higher education policy and talent training are failing to meet the ever-changing expectations of employers and society in Taiwan, resulting in a gap between university education and employment. We used social cognitive career theory to explore the relationships between problem-based learning, teachers' transformational leadership, and students' self-efficacy and employability. Participants were 619 undergraduates from 12 Taiwanese higher education institutions. We performed structural equation modeling and found that there were significant positive correlations between students' self-efficacy, problem-based learning, and employability, along with teachers' transformational leadership. Further, problem-based learning and the students' self-efficacy were key mediators of the relationship between teachers' transformational leadership and students' employability. Implications are discussed for related issues and future research involving models of students' employability.

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