The distinctive features of well-defined, three-dimensional macromolecules with topologies designed to enhance solubility and amplify end-group functionality facilitated nanophase morphologies in mixtures with organosilicates and ultimately nanoporous organosilicate networks. Novel macromolecular architectures including dendritic and star-shaped polymers and organic nanoparticles were prepared by a modular approach from several libraries of building blocks including various generations of dendritic initiators and dendrons, selectively placed to amplify functionality and/or arm number, coupled with living polymerization techniques. Mixtures of an organosilicate and the macromolecular template were deposited, cured, and the phase separation of the organic component, organized the vitrifying organosilicate into nanostructures. Removal of the sacrificial macromolecular template, also denoted as porogen, by thermolysis, yielded the desired nanoporous organosilicate, and the size scale of phase separation was strongly dependent on the chain topology. These materials were designed for use as interlayer, ultra-low dielectric insulators for on-chip applications with dielectric constant values as low as 1.5. The porogen design, chemistry and role of polymer architecture on hybrid and pore morphology will be emphasized.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/1521-3765(20020802)8:15<3308::AID-CHEM3308>3.0.CO;2-D | DOI Listing |
Polymers (Basel)
December 2024
Industrial Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece.
Well-defined amorphous/semi-crystalline statistical copolymers of n-dodecyl isocyanate, DDIC, and allyl isocyanate, ALIC, were synthesized via coordination polymerization using the chiral half-titanocene complex CpTiCl(O-(S)-2-Bu) as an initiator. In the frame of the terminal model, the monomer reactivity ratios of the statistical copolymers were calculated using both well-known linear graphical methods and the computer program COPOINT. The molecular and structural characteristics of the copolymers were also calculated.
View Article and Find Full Text PDFAnal Chem
January 2025
Separation Science Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4bis, B-9000 Ghent, Belgium.
Addressing the global challenge of ensuring access to safe drinking water, especially in developing countries, demands cost-effective, eco-friendly, and readily available technologies. The persistence, toxicity, and bioaccumulation potential of organic pollutants arising from various human activities pose substantial hurdles. While high-performance liquid chromatography coupled with high-resolution mass spectrometry (HPLC-HRMS) is a widely utilized technique for identifying pollutants in water, the multitude of structures for a single elemental composition complicates structural identification.
View Article and Find Full Text PDFMacromol Rapid Commun
January 2025
Key Laboratory of Multi-Scale Manufacturing Technology, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing College, University of Chinese Academy of Sciences, Chongqing, 400714, P. R. China.
As a recent focal point of research, soft electronics encompass various factors that synergistically enhance their mechanical properties and ensure stable electrical performance. However, challenges such as immiscible conductive fillers, poor phase interfaces, and unstable conductive networks hinder the overall efficacy of these materials. To address these issues, a hydrogel featuring an oriented interpenetrating network structure (OIPN) is developed.
View Article and Find Full Text PDFSubcell Biochem
December 2024
Department of Macromolecular Structure, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain.
Viral particles consist essentially of a proteinaceous capsid that protects the genome and is also involved in many functions during the virus life cycle. In structurally simple viruses, the capsid consists of a number of copies of the same, or a few different proteins organized into a symmetric oligomer. Structurally complex viruses present a larger variety of components in their capsids than simple viruses.
View Article and Find Full Text PDFSubcell Biochem
December 2024
Department of Macromolecular Structure, Centro Nacional de Biotecnología (CNB-CSIC), Madrid, Spain.
Viruses are elegant macromolecular assemblies and constitute a paradigm of the economy of genomic resources; they must use simple general principles to complete their life cycles successfully. Viruses need only one or a few different capsid structural subunits to build an infectious particle, which is possible for two reasons: extensive use of symmetry and built-in conformational flexibility. Although viruses come in many shapes and sizes, two major symmetric assemblies are found: icosahedral and helical.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!