Search

Superhydrophilic coatings are prominent in various industries, including automotive, and consumer electronics. However, challenges persist in terms of mechanical performance and durability. This study focuses on the development of organic–inorganic hybrid nanoparticles for superhydrophilic coatings that exhibit exceptional thermomechanical stability and long‐term durability. Employing green chemistry, polyethylene glycols (PEGs) are grafted onto silica nanoparticles, controlling the PEG molecular weight from 200 to 1000 to systematically investigate its impact on coating characteristics. Additionally, the intriguing phenomenon of phase separation facilitated by a polyurethane binder and its effects on both morphology and hydrophilicity is investigated. All hybrid coatings consistently exhibit remarkable superhydrophilicity, with contact angles consistently below 10°, the lowest being 1.4°. Longer PEG chains played a pivotal role in enhancing the thermal stability of the grafted PEG shell within the hybrid nanoparticles, achieving a maximum enhancement in decomposition temperature of 150 °C. Furthermore, the PEG shell substantially improves strain durability, with SiO2‐PEG 1000–50% exhibiting outstanding transmittance retention of 100% without any cracks even under a 100% tensile strain. SiO2‐PEG 200 emerged as the champion in maintaining superhydrophilicity throughout a 20‐day long‐term durability assessment. Moreover, the research has unveiled the intricate degradation mechanism responsible for the decline in hydrophilicity in these hybrid coatings. [ABSTRACT FROM AUTHOR]

Light scattering holds immense significance in various applications, including LED lighting, display enhancement, and solar cell optimization, emphasizing the critical role of understanding scattering mechanisms, especially light–matter interactions, achieving effective optical diffusion. Consequently, the influence of stimuli on material properties, including refractive indices and thermal expansion behavior, has emerged as a pivotal consideration, leading to the development of stimuli‐responsive light scattering modifier. Here, a temperature‐sensitive light scattering modifier composed of poly(methyl methacrylate‐co‐styrene) and poly(ethylene‐co‐vinyl acetate) is presented as scattering particles and matrix, respectively, using a melt‐blending process. Optical properties are evaluated across controlled temperatures 0–70 °C. These findings demonstrate an increasing trend in diffuse transmission and haze as temperatures increased across all light scattering modifiers. Significantly, the optimized light scattering modifier, integrating a dual particle system, showcased uniform reduction gaps in parallel transmission and adjustable haze characteristics across the visible spectrum under temperature control. This optical modifier achieved a total transmission of 92% and adjustable haze levels ranging from 35% to 90% under temperature control. Furthermore, this fabrication of three‐layer films incorporating the light scattering modifier exhibited identical characteristics to the developed light scattering modifier, emphasizing their potential for seamless integration across diverse technological domains. [ABSTRACT FROM AUTHOR]

Polyglycolic acid (PGA) is a promising polymer in the packaging field owing to its excellent hydrolysis, heat resistance, and gas barrier properties, but it is limited in application due to its poor toughness. For this reason, a covalently bonded chain extender is introduced to increase compatibility with flexible polymers. However, covalent bonds are unfavorable for application to degradable plastics because of the energy required for reverse reactions. Therefore, we intended to effectively control the ductility of blending plastics by using a novel ionic chain extender with a relatively weaker non-covalent bond than the existing covalent bond. Polycaprolactone (PCL), which has biodegradability and flexibility, was selected as a blending polymer. For comparison, a covalently reactive chain extender (G-CE) and a non-covalently ionic chain extender (D-CE) were synthesized and compounded with blending plastics. Each chain extender improved the compatibility between PGA and PCL, and the ductility of the PGA/PCL blending plastics was more greatly enhanced with non-covalently bonded D-CE than with covalently bonded G-CE. At this time, the ductility of the PGA/PCL(90/10) blending plastic without CE was 7.2%, the ductility of blending plastic with D-CE (10D) was 26.6%, and the ductility of blending plastic with G-CE (10G) was 18.6%. Therefore, it was confirmed that the novel ionic chain extender inducing non-covalent bonds improves the compatibility between PGA and PCL and is more advantageous in enhancing ductility through a reversible reaction. [ABSTRACT FROM AUTHOR]

The poem "CENTO FOR THE FUTURE IN WHICH I AM ALIVE" by Joseph Jang is presented. First Line: when the fish die all at once and appear on the banks all at once; Last Line: and choose the clothes I'll be buried in.

The influence of N-substituent and p K a of azole rings has been investigated for the performance of high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Imidazole, benzimidazole, and triazole groups were functionalized on the side chains of poly(phenylene oxide), respectively. Each azole group is categorized by their N-substituent into two types: unsubstituted and methyl-substituted azoles. The membranes with methyl-substituted azoles showed higher phosphoric acid (PA) doping levels with an average increase of 20% compared to those with unsubstituted azoles in the full-doped states. However, unsubstituted azoles more effectively improved the proton conductivity and the membrane with unsubstituted imidazole (IMPPO-H) showed a high anhydrous proton conductivity of 153 mS/cm at 150 °C. In contrast, the membranes with methyl-substituted azoles showed a higher PA retention with an average increase of 81% compared to those with unsubstituted azoles. The higher PA retention of methyl-substituted azoles also led to the higher fuel cell performance with the maximum increase of 95% in the power density. It was also revealed that higher p K a of azoles enhanced the PA retention and the fuel cell performance. Based on the experimental results of PA retention and density functional theory calculations, the PA loss mechanism was also proposed.