Amirali Khalili’s Post

This work demonstrates a scalable method for manufacturing high-performance fully printed thermoelectric generators (TEGs) as a cost-effective energy harvesting solution. A new one-pot synthesis method is developed for a high-performance Ag2Se-based n-type paste, used in conjunction with a Bi-Sb-Te-based paste for p-type legs, to fabricate a fully printed origami TEG. The n-type film achieves a power factor of 13.5 µW cm−1 K−2 and a figure-of-merit (ZT) of approximately 0.92. Additionally, a printable carbon paste is introduced to reduce contact resistances between thermoelectric and electrode materials. The origami folded TEG exhibits an open-circuit voltage (VOC) of 284 mV, a power output of 370.88 µW, and a high power density of 10.72 Wm−2 at a temperature difference (∆T) of 80.7 K, without requiring pressure treatment or vacuum sintering. These findings highlight the scalability of the process and the potential of printed origami TEGs for powering IoT devices using low-grade waste heat. Read more details: https://lnkd.in/ea6-dyc3 #polymerscience #energy

This study investigates the interaction between polymeric micelles and mucin, which is crucial for optimizing drug delivery systems. Using a multidisciplinary approach, the research employs techniques such as quartz crystal microbalance with dissipation, surface-enhanced Raman scattering, and isothermal titration calorimetry to understand these interactions. Key findings include the integration of polymeric micelles within the mucin layer, hydrogen bonding within the mucin's hydrophilic core, and multiple non-specific binding sites on the protein backbone. The periodic acid-Schiff stain assay quantifies the binding amount of mucin to nanoparticles, and motility studies reveal the impact of mucin binding on nanoparticle motion. The insights gained aim to enhance drug delivery formulations and advance clinical applications. Read more details: https://lnkd.in/eVbzg9Zs #polymerscience

This article discusses the development of a poly(urea-urethane) energetic elastomer synthesized from glycidyl azido polymer (GAP), isophorone diisocyanate (IPDI), and 2-aminophenyl disulfide (2-APD). The elastomer features a hybrid dynamic lock with multilevel H-bonds and disulfide bonds, enhancing dynamic interactions, chain diffusion, and physical crosslinking density. This design yields robust mechanical properties: tensile strength of 0.72 MPa, stretchability of 1631%, and toughness of 8.95 MJ/m³. The elastomer demonstrates high self-healing efficiency (98.4% at 60°C) and significant heat release (1750.46 J/g). It also supports high-solid content (80 wt%) composites with excellent micro-defect self-healing (97.8%) and recyclability without losing mechanical performance, offering promising applications in energetic materials. Read more details: https://lnkd.in/evGsW94x #polymerscience

The study introduces a double-network (DN) engineering strategy to create highly robust and electronically conductive hydrogels for energy applications. Traditional methods of mixing conductive additives with hydrophilic polymers compromise mechanical strength and conductivity. Here, a polyvinyl alcohol (PVA) and polypyrrole (PPy) DN hydrogel is developed, featuring a conductive PPy-PA network formed through in-situ ultrafast gelation, and a tough PVA network formed via freezing/thawing. The resulting hydrogel demonstrates impressive properties: electrical conductivity of ~6.8 S/m, mechanical strength of ~0.39 MPa, and elastic moduli of ~0.1 MPa. When used in supercapacitors, the hydrogels show a high capacitance of ~280.7 F/g, maintain over 94.3% capacity after 2000 charge/discharge cycles, and perform well even at −20°C. The synergy between the conductive PPy-PA network and the DN structure enhances these properties, offering a versatile approach for integrating conductive materials into DN hydrogels for advanced electronics, surpassing commonly used PEDOT:PSS-based hydrogels. Read more details: https://lnkd.in/ePMX2d8k #polymerscience

This study introduces a dual-salt quasi-solid polymer electrolyte (QSPE) designed for lithium-metal batteries (LMBs). The QSPE combines a single-ion conductor polymer (SICP) with a traditional dual-ion lithium salt to address concentration polarization and lithium dendrite formation. The dual-salt network is created through in-situ crosslinking copolymerization, resulting in a high lithium-ion transference number (0.75) and good ionic conductivity (1.16 × 10−3 S cm−1 at 30°C). The SICP polyanions reduce the migration of free anions, decreasing concentration polarization and preventing dendrite growth. This enhances the Li||LiFePO4 cell's cycle stability (2000 cycles) and capacity retention (90% at 30°C), presenting a promising approach for high-performance polymer LMBs. Read more details: https://lnkd.in/ezuqGweK #polymerscience

This study introduces a novel polysiloxane-based light-responsive liquid crystal elastomer (LCE) with donor–acceptor Stenhouse adduct (DASA) side-chains, synthesized using a late-stage functionalization method. This new approach maintains the molecular alignment achieved by the traditional Finkelmann method, enabling the creation of well-aligned LCE films ranging from 400 µm to 5 mm thick. The LCEs exhibit 2D planar actuation and complete bleaching under low-intensity visible light (100–200 mW cm−2), and bending followed by contraction under higher-intensity light (300 mW cm−2). These responses are repeatable, with the study highlighting how light intensity and heat generation affect DASA's photothermal equilibrium and photoresponsive behavior. This work paves the way for advanced LCE actuators beyond thin films and UV-light dependence. Read more details: https://lnkd.in/eBebW7Fi #polymerscience #actuators

Tardigrades are highly resilient organisms that can survive extreme conditions. Inspired by this adaptability, researchers designed biomimetic soft actuators (BSAs) capable of enduring harsh environments. Unlike previous materials, these BSAs mimic tardigrades' anatomical structures and adaptive resilience, particularly their dehydration and rehydration abilities. The BSAs use dual-layer hydrogel spheres with embedded fluid bubbles, creating durable, smart structures that withstand compressive, thermal, and radiation stimuli through thermoresponsive shape morphing. Demonstrations include driving an artificial muscle and regenerating after chemical exposure. These versatile BSAs are promising for autonomous applications in challenging environments like aqueous effluents, deserts, polar regions, and outer space. Read more details: https://lnkd.in/eBuyBjAn #polymerscience #hydrogel

This work enhances self-healing coatings by incorporating surface-tethered covalently adaptable networks (CANs). Using surface-initiated polymerization combined with spray-coating, it deposits polymers with reversible crosslinks. These coatings, based on reversible vinylogous urethane bonds from 2-(acetoacetoxy)ethyl methacrylate-based polymers and tris(2-aminoethyl) amine (TREN), exhibit superior self-healing properties. TREN facilitates reversible bonding between the spray-coated and surface-tethered polymers. Without a polymer brush layer, the coatings fail to fully self-heal and are prone to solvent damage and shear delamination. The approach allows autonomous self-healing of scratches at elevated temperatures or more gradually at ambient conditions, significantly enhancing coating durability and robustness. Read more details: https://lnkd.in/eY84Nrvi #polymerscience #coating

Biological organisms adapt through mechanisms such as self-amputation, regeneration, and collective behavior. Examples include reptiles, crustaceans, and insects that self-amputate appendages in response to threats, and ants that fuse temporarily to form structures like bridges. Inspired by these natural processes, the study introduces a reversible cohesive interface made of thermoplastic elastomer for soft robotics. This interface allows for strong attachment and easy detachment of robot modules without direct human handling, maintaining mechanical congruence with soft robotics materials. The utility of this interface is demonstrated with a soft quadruped robot that can self-amputate a limb when stuck and a cluster of soft-crawling robots that fuse to cross a gap. This research highlights the potential for robots to radically change shape by adding or subtracting mass and emphasizes the importance of interfacial stiffness in both biological and artificial systems. Read more details: https://lnkd.in/eQbCfHCn #polymerscience #softrobotics

Liquid crystal elastomers (LCEs) are advantageous for creating shape-morphable structures due to their significant deformation capabilities, adjustable properties, and low energy requirements. By combining a contracting LCE with a flexible but inert layer, bending actuation can be achieved. This study introduces a method for fabricating thermoresponsive LCE and fabric bilayer actuators, assessing their performance as bending actuators. It was found that different strain-limiting fabrics produce varying actuation outputs and curvatures, with the interfacial adhesion of the bilayer playing a more crucial role than the stiffness of the strain-limiting layer. The effectiveness of the LCE-fabric actuator is demonstrated in a soft robotic gripper, suggesting that the design of LCE and fabric bilayer structures can be optimized for complex and programmable out-of-plane morphing. Read more details: https://lnkd.in/eVE9HzTW #polymerscience #softrobotic