Hybrid Nanocomposites on the Basis of Synthetic Oxide Nanofillers
Hybrid Polymer-Inorganic Nanocomposites with New Level of Thermomechanical and Electrophysical Properties on the Basis of Synthetic Oxide Nanofillers of Specified Shape and Composition
Tech Area / Field
- CHE-POL/Polymer Chemistry/Chemistry
3 Approved without Funding
Institute of Macromolecular Compounds, Russia, St Petersburg
- Delivery Systems International, Russia, St Petersburg\nInstitute of Silicate Chemistry, Russia, St Petersburg
- University of Southern Mississippi / School of Polymers and High Performance Materials, USA, MS, Hattiesburg\nTechnical University Hamburg-Hamburg / Institute of Polymer Composites, Germany, Hamburg\nPPG Industries, Inc., USA, PA, Allison Park\nNagoya Institute of Technology, Japan, Nagoya
Project summaryAt present creating hybrid polymer-inorganic nanocomposites, that is polymer heterophase materials where the size of inorganic phase particles are in the nanometric range, becomes one of the most effective ways to develop new types of polymer materials. It is worth noting that polymer materials being formed of organic (polymer) and inorganic (nanoparticle) constituents and which are resulting from such joining on molecular and permolecular levels represent, as most experiments register, absolutely new polymer structures which are not just a simple “sum” of components which constitute them. In the case of targeted joining, new materials are formed which have new levels of physical-chemical, mechanical, and other properties, including electrical and semiconductive ones.
A large number of publications over the last decade are devoted to nanocomposites on the basis of polymer matrix reinforced with non-carbon nanofillers, such as montmorillonite (MMT) and hectorite. MMT is a natural laminated silicate with layers of 1nm at most. Polymer-MMT nanocomposite is a new class of reinforced plastics being formed due to uniform dispersion of MMT nanoparticles in polymer matrix. Such nanocomposites have great scientific and practical importance due to their high mechanical and barrier properties, as well as due to their high fire-resistance.
But such mineral usually represent a mixture of several natural compounds non-uniformed in composition and particle size. Minerals from different deposits might differ considerably in composition. It certainly complicates the task of creating functional nanocomposites with given properties on the basis of nanomaterials. Therefore, it is of interest to produce nanocomposites by making use of synthetic laminated compounds of certain compositions and particle size, as well as to develop particles of various morphology as fillers for nanocomposites.
Any data on use of nanosized nanoparticles on the basis of synthetic oxide and hydroxide compounds for producing nanocomposites are not available so far in the literature. Synthetic fillers give a possibility to use, in addition to laminated compounds, nanoparticles of other morphology- nanotubes and particles of isometric shape and various chemical compositions.
It is important in terms of economic expedience that those new nanocomposite materials can be produced on the basis of known polymers produced commercially.
In this project the following aspects are planned.
Especially attractive are nanocomposites on the basis of polyimide matrixes due to their high thermic, mechanical, and dielectric characteristics. It is expected that if polyimide-oxide nanocomposites are developed purposefully, they can find wide-scale applications in electronics, aerospace industry (constructional and abrasive materials), medicine (biomaterials for medical apparatuses and sensors), separation membranes, microelectronic systems, etc.
The next direction in development of nanocomposites is film coatings on the basis of fluorine polymers widely used as varnish coatings, also in electronics where the problem is to increase strength of adhesion to underlying materials of various natures, to raise resistance to abrasive effects, to increase electric strength and protection against moisture.
As matrixes processed by method of free casting and cold hardening it is suggested to use standard polyurethanes, polyepoxides, and liquid siloxane rubbers. What is non-standard in the present Project is a special modification of nanofillers for ensuring the chemical linking of their surfaces with functional groups of basic polymer chain and formation of system “network in a network” combining organic (polymer) and inorganic three-dimensional structures.
Considerable changes (by a few times) in breaking strain, module, and polymers dynamic properties when polymers were supplemented with just about 5% by weight of nanoparticles possessing great specific surface and considerable anisotropy of sizes are often related to appearance of so-called percolation cluster, or network, from nearby filler particles which is spreading throughout entire macroscopic sample. Therefore, it is certainly important to study correlation between percolation threshold in systems with various dimensionality, orientation, and anisotropy of filler particles and filler critical concentrations. Development of models explaining mechanical and viscoelastic behavior of polymer systems having several levels of structural organization will be given special attention in the proposed project as such models are needed for description of nanocomposites non-linear behavior.
The proposed Project is based on substantial scientific, technological, and methodological foundation of activities being carried out so far in organizations – participants in the Project.
Thus, at ICS RAS they have developed methods for hydrothermal synthesis of laminated nanosilicates of nanosized tubes and particles of isometric form and various chemical composition; they have considerably succeeded in the field of controlling nanoparticles structure by varying the mode of hydrothermal synthesis.
At IMC RAS they have produced new polymer materials –partially crystallized polyimides and polyimides with structure of semi-mutually-permeable networks capable of forming new micro- and nanocomposites distinguished from traditional polymer composites by developed structural organization not only within the matrix volume, but also at the filler-matrix interface.
Research workers at ZAO “DELSI” (subsidiary enterprise of Russian Scientific Center “Applied Chemistry” have vast experience in development of formulations and technologies for producing protective coatings and filled block polymer systems. Besides, work on microencapsulating dispersed solid materials gives a good basis for modification of nanofillers’ surface which is a new and most important part of work on creating nanocomposites.
All three organizations – participants in the Project – employ high qualification experts – chemists and physicists, including two academicians, two associate members of the Russian Academy of Sciences, two professors (doctors of science), two doctors of science.
Project’s goal is to create principles of technologies for synthesis of nanosized oxide fillers of various shape: laminated, nanotubes, particles of isometric form. It is planned to regulate their chemical composition and a possibility of intercolation of transition metals atoms to provide for specific electro-physical properties. By using the above-listed nanofillers, it is planned to develop formulations and laboratory technologies for producing (including modification of filler surface, conditions of dispersion, etc.) film and cast nanocomposites with high physical-mechanical, new barrier, and electro-physical characteristics potentially suitable for aerospace, electronic, car-building, medical instrument industries, new hydrogen energy engineering.