This report studied the changes in the slow dynamics of polyacrylate by adding a hindered phenol (CA) capable of forming three intermolecular hydrogen bonds (inter-HBs) per molecule with the polymer chain. The CA molecule apparently diminishes the slow modes (with lower peak temperatures and peak heights) of the polyacrylate, although it has a higher glass transition temperature () than the acrylic matrix, and the rigid CA-bridged HB network significantly amplifies the α-relaxation near (with higher peak temperatures and peak heights). Consequently, the mixtures exhibit a diminishing slow mode that gradually merges with the prominent -peak with increasing CA loadings. The anomalous dynamics concerning the opposite behaviors of the slow mode and α-relaxation was further rationalized in terms of dissociation of inter-HBs when the temperature is higher than , together with the small molecule-alleviated macromolecular connectivity. This work provides essential insights into the slow dynamics of such HB-driven hybrids, and paves the way for tailoring the viscous flow properties of the hybrid material from a molecular level perspective.
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http://dx.doi.org/10.1039/d2sm00453d | DOI Listing |
Nanomaterials (Basel)
March 2025
Institute of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Ibaraki, Japan.
The transport and fate of antibiotics are significantly influenced by co-existing colloidal and nanosized substances, such as clay particles. Montmorillonite, a common clay mineral with a thin nano-sheet-like structure, enhances antibiotic (e.g.
View Article and Find Full Text PDFSoft Matter
March 2025
School of Mathematical, Physical, and Computational Sciences, University of Reading, Reading, RG6 6AX, UK.
Biopolymers tend to form fibrils that self-assemble into open network structures. While permanently crosslinked flexible polymers are relatively well understood, structure-property relationships of open networks and pseudo-gels formed by bundles of biopolymers are still controversial. Here we employ a generic coarse-grained bead-spring chain model incorporating semiflexibility and cohesive nonbonded interactions, that forms physical instead of chemical crosslinks.
View Article and Find Full Text PDFWearable Technol
February 2025
Neuromuscular Robotics Laboratory, Department of Biomechanical Engineering, University of Twente, Enschede, the Netherlands.
Research in lower limb wearable robotic control has largely focused on reducing the metabolic cost of walking or compensating for a portion of the biological joint torque, for example, by applying support proportional to estimated biological joint torques. However, due to different musculotendon unit (MTU) contractile speed properties, less attention has been given to the development of wearable robotic controllers that can steer MTU dynamics directly. Therefore, closed-loop control of MTU dynamics needs to be robust across fiber phenotypes, that is ranging from slow type I to fast type IIx in humans.
View Article and Find Full Text PDFComput Biol Med
March 2025
Dept. of Electromagnetic and Biomedical Engineering, Faculty of Electrical Engineering and Information Technology, University of Zilina, Zilina, Slovakia. Electronic address:
Background: Microvascular function, particularly of the plantar foot, reflects overall vascular health and is influenced by physiological oscillators such as heart rate, respiratory, myogenic, and neurogenic rhythms. Slow deep breathing modulates autonomic nervous system activity and affects peripheral microcirculation. This study investigates the effects of slow deep breathing on plantar foot perfusion using photoplethysmography imaging (PPGI).
View Article and Find Full Text PDFEpilepsy Behav
March 2025
Swiss Epilepsy Center, Bleulerstrasse 60, Zurich 8008, Switzerland; University of Zurich, Department of Psychology, Binzmuehlestrasse 14, Zurich 8050, Switzerland. Electronic address:
Background And Objectives: Social cognition (e.g., theory of mind and emotion recognition) is frequently impaired in people with epilepsy (PWE) and plays a critical role in social functioning.
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