Mesoporous silica films templated by pluronic P123 were prepared using spin and dip coating. The ordered cylindrical structure within the films deforms due to shrinkage during calcination. Grazing-incidence small-angle X-ray scattering (GISAXS) measurements reveal that both the unit cell and the cross section of the pores decrease in size, mainly normal to the surface of the substrate, leading to elliptical cross sections of the pores with axis ratios of about 1:2. Water take-up by the pores upon changing the relative humidity can be monitored quantitatively by the shift in the critical angle of X-ray reflection as seen by the Yoneda peak.
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http://dx.doi.org/10.1107/S1600576716013698 | DOI Listing |
Adv Sci (Weinh)
January 2025
Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
Non-close-packed crystalline arrays of colloidal particles in an elastic matrix exhibit mechanochromism. However, small interparticle distances often limit the range of reversible color shifts and reduce reflectivity during a blueshift. A straightforward, reproducible strategy using matrix swelling to increase interparticle distance and improve mechanochromic performance is presented.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Graduate School of Advanced Science and Technology, Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Nomi 923-1292, Japan.
Polybenzimidazole (PBI) is a high-performance polymer known for its excellent thermal stability, mechanical strength, and chemical resistance, attributes that are derived from its unique structure comprising repeated benzene and imidazole rings. However, limitations such as relatively low thermal stability and moisture sensitivity restrict its application as a super engineering plastic. In this study, amide groups are incorporated into the PBI backbone to synthesize the copolymer poly(BI--A), effecting a structural modification at the molecular level.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Institute of Nuclear Physics Polish Academy of Sciences, 31-342 Krakow, Poland.
The resistivity of the silica SBA-15 type can be significantly improved by forming a thin layer of carbon on the pore surface. This is possible through the carbonization reaction of a surfactant used as a structure-directing agent in the synthesis of mesostructured silica materials. The synthesis of this type of silica-carbon composite (SBA-C) is based on the use of sulfuric acid to create a carbon layer from surfactant molecules encapsulated in silica mesopores.
View Article and Find Full Text PDFNanoscale
January 2025
CBMN, CNRS, UMR 5248, University of Bordeaux, 33600 Pessac, France.
Cast films of racemic helicene derivatives adsorbed onto the surface of nanometric silica helices with controlled handedness exhibited distinct CD signals, whereas no CD signal was observed in the absence of silica nanohelices. These CD signals originate from the helical supramolecular assemblies formed by the racemic mixture of helicenes, with no evidence of enantiospecific adsorption. Interestingly, when enantiomerically pure forms of these helicenes were drop-cast onto the silica helices, different CD spectra were observed depending on the combination of the helicenes' handedness with that of the silica nanohelices.
View Article and Find Full Text PDFLangmuir
January 2025
State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, People's Republic of China.
The protein carrier and encapsulation system based on polyelectrolytes plays crucial roles in drug research and development. Traditional methods such as isothermal titration calorimetry and molecular dynamics simulation have illuminated parts of this complex relationship. However, they fall short of capturing the full picture of the interaction during the carrier's fabrication and protein loading dynamics.
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