Next Article in Journal
Enlarged Pore Size Chiral Mesoporous Silica Nanoparticles Loaded Poorly Water-Soluble Drug Perform Superior Delivery Effect
Next Article in Special Issue
Water in Mesoporous Confinement: Glass-To-Liquid Transition or Freezing of Molecular Reorientation Dynamics?
Previous Article in Journal
Site Selectivity in Pd-Catalyzed Reactions of α-Diazo-α-(methoxycarbonyl)acetamides: Effects of Catalysts and Substrate Substitution in the Synthesis of Oxindoles and β-Lactams
Previous Article in Special Issue
Hydroxyl-Group Identification Using O K-Edge XAFS in Porous Glass Fabricated by Hydrothermal Reaction and Low-Temperature Foaming
Open AccessArticle

Combining Soft Polysilazanes with Melt-Shear Organization of Core–Shell Particles: On the Road to Polymer-Templated Porous Ceramics

1
Chair in Polymer Chemistry, Saarland University, Campus Saarbrücken C4 2, 66123 Saarbrücken, Germany
2
Department of Materials and Earth Sciences, Technische Universität Darmstadt, Otto-Berndt-Str. 3, 64287 Darmstadt, Germany
3
INM- Leibniz Institute for New Materials, Campus D2 2, Saarland University, 66123 Saarbrücken, Germany
*
Author to whom correspondence should be addressed.
Academic Editor: Sergio Navalon
Molecules 2019, 24(19), 3553; https://doi.org/10.3390/molecules24193553
Received: 27 August 2019 / Revised: 26 September 2019 / Accepted: 29 September 2019 / Published: 30 September 2019
(This article belongs to the Special Issue Advances in Porous Materials)
The preparation of ordered macroporous SiCN ceramics has attracted significant interest and is an attractive area for various applications, e.g., in the fields of catalysis, gas adsorption, or membranes. Non-oxidic ceramics, such as SiCN, own a great stability based on the covalent bonds between the containing elements, which leads to interesting properties concerning resistance and stability at high temperature. Their peculiar properties have become more and more important for a manifold of applications, like catalysis or separation processes, at high temperatures. Within this work, a feasible approach for the preparation of ordered porous materials by taking advantage of polymer-derived ceramics is presented. To gain access to free-standing films consisting of porous ceramic materials, the combination of monodisperse organic polymer-based colloids with diameters of 130 nm and 180 nm featuring a processable preceramic polymer is essential. For this purpose, the tailored design of hybrid organic/inorganic particles featuring anchoring sites for a preceramic polymer in the soft shell material is developed. Moreover, polymer-based core particles are used as sacrificial template for the generation of pores, while the preceramic shell polymer can be converted to the ceramic matrix after thermal treatment. Two different routes for the polymer particles, which can be obtained by emulsion polymerization, are followed for covalently linking the preceramic polysilazane Durazane1800 (Merck, Germany): (i) Free radical polymerization and (ii) atom transfer radical polymerization (ATRP) conditions. These hybrid hard core/soft shell particles can be processed via the so-called melt-shear organization for the one-step preparation of free-standing particle films. A major advantage of this technique is the absence of any solvent or dispersion medium, enabling the core particles to merge into ordered particle stacks based on the soft preceramic shell. Subsequent ceramization of the colloidal crystal films leads to core particle degradation and transformation into porous ceramics with ceramic yields of 18–54%. View Full-Text
Keywords: polymer particle synthesis; particle processing; polymer chemistry; preceramic materials; melt-shear organization; polymer derived ceramic; core–shell polymer particle synthesis; particle processing; polymer chemistry; preceramic materials; melt-shear organization; polymer derived ceramic; core–shell
Show Figures

Graphical abstract

MDPI and ACS Style

Boehm, A.K.; Ionescu, E.; Koch, M.; Gallei, M. Combining Soft Polysilazanes with Melt-Shear Organization of Core–Shell Particles: On the Road to Polymer-Templated Porous Ceramics. Molecules 2019, 24, 3553.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop