In this study, we applied oblique angle deposition to a modified initiated chemical vapor deposition (iCVD) process to synthesize porous poly(methacrylic acid) (PMAA) films. During the modified iCVD process, frozen monomer molecules are first captured on a cooled substrate, then polymerization occurs via a free radical polymerization mechanism, and finally, the excess monomer is sublimated, resulting in a porous polymer film. We found that delivering the monomer through an extension at an oblique angle resulted in porous films with three morphological regions. Region 1 is located nearest to the monomer extension outlet and consists of porous polymer pillars; region 2 consists of densified pillars, which occur due to the recapturing and polymerization of the sublimated monomer; and region 3 is located furthest from the monomer extension outlet and consists of dendritic structures, which occur due to low monomer concentration. We investigated the role of substrate temperature and monomer deposition time on the growth process. We found that changing the extension angle influenced the location of the regions and the film coverage across the substrate. Our results provide useful guidelines for tuning the structures within porous polymer films by varying the angle of monomer delivery.
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http://dx.doi.org/10.1021/acs.langmuir.2c02876 | DOI Listing |
Mater Horiz
January 2025
Key Laboratory of Polymer Processing Engineering of the Ministry of Education, National Engineering Research Center of Novel Equipment for Polymer Processing, Guangdong Provincial Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, South China University of Technology, Guangzhou 510641, People's Republic of China.
Passive daytime radiative cooling offers a promising approach to address energy, environmental, and safety issues caused by global warming. However, the contradiction between high radiative cooling performance and long-lasting ultraviolet (UV) durability is a primary limitation at the current stage. Here, inspired by the ability of epidermal cells and palisade cells on the leaf surface to protect internal leaf structures (such as chloroplasts and nuclei) under drought and high-temperature conditions, a double-layer passive radiative cooling (PRC) porous membrane, which consists of an upper protective layer densely packed with highly ultraviolet-reflective inorganic particles and a bottom cooling layer doped with a variety of optically characterized inorganic particles, was developed to overcome these challenges.
View Article and Find Full Text PDFNanomicro Lett
January 2025
Fujian Provincial Key Laboratory of Fire Retardant Materials, College of Materials, Xiamen University, Xiamen, 361000, People's Republic of China.
In recent decades, annual urban fire incidents, including those involving ancient wooden buildings burned, transportation, and solar panels, have increased, leading to significant loss of human life and property. Addressing this issue without altering the surface morphology or interfering with optical behavior of flammable materials poses a substantial challenge. Herein, we present a transparent, low thickness, ceramifiable nanosystem coating composed of a highly adhesive base (poly(SSS-co-HEMA)), nanoscale layered double hydroxide sheets as ceramic precursors, and supramolecular melamine di-borate as an accelerator.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
CAS Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan 030001, China. Electronic address:
The development of advanced bifunctional oxygen electrocatalysts for the oxygen reduction reactions (ORR) and oxygen evolution reactions (OER) is crucial for the practical application of zinc-air batteries (ZABs). Herein, porous carbon nanosheets integrated with abundant graphene-wrapped CoO and CoNx (CoO/CoNx-C) were successfully fabricated through a simple one-step pyrolysis. With convenient porous channel and large accessible surface, abundant CoO/CoNx species and graphene wrapping structure, CoO/CoNx-C exhibited a half-wave potential of 0.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Pharmaceutical Chemistry, Semmelweis University, Hőgyes Endre U. 9, 1092, Budapest, Hungary.
Microtiter-plate-based systems are unified platforms of high-throughput experimentation (HTE). These polymeric devices are used worldwide on a daily basis-mainly in the pharmaceutical industry-for parallel syntheses, reaction optimization, various preclinical studies and high-throughput screening methods. Accordingly, laboratory automation today aims to handle these commercially available multiwell plates, making developments focused on their modifications a priority area of modern applied research.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
School of Chemistry and Materials Science, Hubei Engineering University, Xiaogan 43200, China.
Passive Radiant Cooling and Heating are green and sustainable methods of radiant heat management without consuming additional energy. However, the absorption of sunlight and poor insulation of materials can reduce radiative cooling and also affect radiative heating performance. Herein, we have constructed porous hierarchical dual-mode silk nanofibrous aerogel (SNF) films with high mechanical toughness and stability using silk nanofibers/GO.
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