Affecting of Gamma-Radiating on Paint Protecting Coatings
Study of Affecting of Gamma-Radiation on Polymeric Solutions and their Component for Deriving Paint Coatings with New Service Properties in Operation Conditions of Atomic Productions and NPP
Tech Area / Field
- CHE-POL/Polymer Chemistry/Chemistry
- CHE-RAD/Photo and Radiation Chemistry/Chemistry
3 Approved without Funding
NIKIMT (Institute of Assembly Technology), Russia, Moscow
- All-Russian Scientific Research Institute of Non-Organic Materials named after A. Bochvar, Russia, Moscow
- Florida State University / Department of Chemistry and Biochemistry, USA, FL, Tallahassee\nLawrence Livermore National Laboratory, USA, CA, Livermore
Project summaryOne of effective paths for improving of radiation situation on objects of a nuclear industry, including nuclear power stations, is the use of protective polymeric coatings with good ability to decontamination of surfaces on radionuclides. Therefore, problem of development of new effective coatings with good ability to decontaminate surfaces of radionuclides will be of importance for a long time.
In present time, the basic tendency in an industry of plastic, is not so to synthesis of new polymers, as modification of well-known polymers. This conclusion concerns to the full and to polymeric protective coatings (lacquers or paints). Among physical and chemical methods of modification of coatings, the methods, connected to application of ionizing radiation, are most perspective.
To the present time, the sufficient experience, in plan of radiation-induced hardening of polymeric coatings, is accumulated. At the same time while painting in engineering, design works, equipment production and surfaces of industrial premises the method of radiation-induced hardening appears ineffective because of limitations superimposed by the significant sizes of painted surfaces, non-uniformity of distribution of an absorbed doze, and absence of necessary portable sources of ionizing radiation for hardening of coatings. Obviously, these defects can be removed, conducting radiation modification of varnish solutions or their components. At irradiation of a semifinished product, the limitations superimposed by the significant sizes of painted surfaces is absent, the difficulties connected with non-uniformity of distribution of a doze on an item are largely removed and radiation-chemical reactions can result in essential improving of properties of coatings.
The radiation chemistry of solutions of polymers contain features radiolysis of a solvent and polymers. In intervals of dozes preceding to gel, radiation-chemical transformations can be accompanied an inoculation of molecules of a solvent on macromolecules of polymer, that results in change its of properties. In this connection, the properties of the coatings generated from previously irradiated solutions of polymers can essentially differ from properties of the coatings generated from not irradiated solutions. The preliminary researches have shown the coatings generated from epoxy solutions in organic solvents been irradiated up to doze 0.15-0.2 Mgy approximately have 10 times better ability of decontamination the surfaces on beta-radionuclides in a comparison with coatings generated from the not irradiated solution. At the same time, the change of other protective properties (adhesion, chemical stability etc.) and also influence of an absorbed doze of irradiation, unfortunately, has not been studied. The coatings can find application for protection of buildings, designs, equipment and surfaces of industrial premises of atomic power stations, as the factor of good ability of decontamination the surfaces from radionuclides in this case is essential. The information on properties of the coatings generated because of other irradiated polymeric solutions, in periodicals has not been detected.
About use of irradiated polymeric bases for producing the polymeric protective coatings on their basis has been found no data. At the same time, as it is known, the action of radiation on of high molecular compounds bring to changes of chemical structure in macromolecules and accompanied by processes of cross-linking and destruction. Thus, the processes of cross-linking and destruction bring to change of solubility of the polymer in an organic solvents, and formation of new chemical structures (on an example, polar oxygencontain groups) can result for a change of adhesion strength. So, as the preliminary research have shown, that coatings of polyvinylchloride prepared from lacquer solution, containing irradiated the base, have adhesion strength tens times larger then steel, in comparison with usual of polyvinylchloride by protective coatings. The increase of solubility of polymeric base in organic solvents in some cases (such as widely used in industry as chemically tolerant coatings based on polyvinylchloride and flouroplaste) is rather actual. It can result to reducing of operations of producing the coating, that will entail decrease of lets of a solvent in atmosphere at realization color of works by methods have limitations on viscosity polymeric protective of a solution (pneumatic dissipation).
Thus, as it shown in the preliminary analysis, property polymeric protective of the coatings generated from irradiated polymeric solutions, and also because of solutions containing previously irradiated polymeric base (and properties of it a solutions) are investigated extremely insufficiently. At the same time, the available data and the preliminary researches proved to a capability of improving of physical-chemical and physical-mechanical properties at coatings after appropriate radiation modification of polymeric solutions and - or polymeric base. Due to this, there is a necessity of researching these coatings in the field of a broad circle of polymeric base and their solutions, subjected of action of radiation.
The purpose offered in the Project of researches is the study of a capability of obtaining of the coatings, with an improved protective properties, from the irradiated polymeric solutions, and also because of solutions containing previously irradiated polymeric base, determination of influence of an absorbed doze on basic physical-chemical and physical-mechanical properties polymeric protective of compositions and coatings.
For reaching the purpose, delivered in The Project, it is supposed to make generalization and a comprehensive analysis of the information on radiation-chemical transformations in polymeric materials and their solutions, and also to execute a complex of experimental works, connected to study of properties radiation-modified polymeric protective of compositions and coatings (viscosity, decontamination of surfaces, an adhesion, strength of the characteristic, internal stresses, chemical stability, permeability), to determine influence on them of an absorbed doze. Also it is supposed to conduct a complex of researches of radiation - chemical transformations in a series of polymeric base and their solutions.
Pursuant to the purposes and problems INTC the Project has an ecological directivity. So, the increase decontamination of surfaces from radionuclides of coatings will cause to reduction of volume of solid and liquid radioactive waste, and increase of solubility polymeric base in polymeric protective compositions to reduction of lets of toxic solvents in atmosphere.