O. V. Stoyanov

Studies on the surface properties and the adhesion to metal of polyethylene coatings modified with primary aromatic amines

The surface free energy and acid-base characteristics of polyethylene coatings formed on steel in the presence of primary aromatic amines (PAAs) were investigated. PAAs were shown to interact with steel by a donor-acceptor mechanism. An increase in the coating adhesion is realized through chemical and physical bond formation between an adhesive and a substrate with the help of the PAA. The free surface energy of the contact-to-metal side of these coatings modified with PAA was shown to grow in parallel with the increase in adhesion. The results correlate with the data on polyethylene surface wetting with nonionic surfactants. Acid-base interactions were found to exert primary control over polyethylenes adhesion to steel.

On the Evaluation of the Acidity and Basicity Parameters of the Surface Free Energy of Polymers

Polymeric surfaces of polyvinylchloride and polymethylmethacrylate were found to be unsuitable when considered to be monopolar. The acid-base properties of these polymers were studied by using the Berger method, and their composition was analyzed by IR-spectroscopy and quantum chemical analysis. In order to determine the acidity and basicity parameters of the surface free energy (SFE) of smooth solid surfaces, the three-dimentional graphical method was proposed based on nonlinear Della Volpe modification of the van Oss-Chaudhury-Good equation.

Determination of free surface-energy parameters using a spatial method

A spatial method for determining acid and base parameters of the free surface energy of different solid surfaces using multidimensional approximation based on reduction of the van Oss-Chaudhury-Good equation to the equation of a plane is developed. The obtained results confirm the efficiency of the spatial method for correct determination of free surface-energy parameters for different substances.

Application of the acid-base approach to explain adhesive properties of modified rubber coatings

The influence of the content and composition of polymeric petroleum resins (PPRs) on the properties of incongealable sealants based on butyl rubber was studied. It was shown that the introduction of PPR B grade increases the adhesion ability of these sealants to duralumin. It was concluded that use of the acid-base approach is a good tool for explaining the nature of adhesive relationships.

Analysis of the Influence of Cardanol Content on the Properties of Phenol-Cardanol-Formaldehyde Novolac Resins

The influence of cardanol content on the molecular-weight distribution and curing kinetics of phenol-cardanol-formaldehyde novolac oligomers is investigated. It is shown that, depending on the cardanol content, the resulting oligomers can be used as components in glues and sealants of different purposes.

The effect of aminoalkoxy and glycidoxyalkoxy silanes on adhesion characteristics of double and triple copolymers of ethylene

The effect of aminoalkoxy and glycidoxyalkoxy silanes on strength of a polyethylene-modified copolymer-metal (polyethylene terephthalate) adhesion joint was studied for double and triple acetate copolymers of ethylene. It was shown that such modification resulted in an essential increase in the deformation-strength and adhesion characteristics of adhesive joints.

Adhesion of polymers: New approaches to determination of surface properties of metals

Determination of the acid-base properties of metal surfaces used as substrates in adhesive compounds was performed by a two-liquid method. It was shown that the suggested method provides a possibility of scientifically grounded selection of a substrate for creating adhesive polymeric-adhesive-metal compounds with a high level of interphase acid-base interaction.

The Influence of the Colloidal Structure of Polymer Blends on the Adhesion Strength of Polyolefin Compositions

The way an adhesive composition peels depends on the competing influences of its physical and mechanical properties and the reduced acidity parameter of the polymer, which forms a continuous phase. In practice, this can mean that on the outside insulation of steel pipes “dilution” of the expensive adhesive, usually a double or triple ethylene copolymer, by the less expensive polyethylene is possible, in a ratio that provides a continuous phase of “adhesion active” components. Considering the large difference in price and the fact that, in Russia, all high-quality adhesive ethylene copolymers are imported, such dilution could be an economically attractive approach.

Tape polymer materials for anti-corrosion insulation of pipelines

The article discusses peculiar features of polymer tape coatings for protecting pipelines and main methods of applying them in a field environment. It is shown that the design of polymer tape coating depends on operational conditions, the conditions of the coating application, and the method of pipeline construction. The main Russian and Western insulating materials are reviewed and some of the technical characteristics of these materials are presented.

Interaction of Adhesives in Metal-Polymer Systems in Acid-Base Approach

A comparative analysis of different methods of evaluating the surface energy and acid-base characteristics of solid smooth polymer surfaces is carried out. It is founded that the surfaces of many studied polymers have low energy and are characterized by low values of acidity parameters; furthermore, their acidbase properties are significantly affected by the preparation of the surface (time and temperature of extrusion, etc.). It is shown that the acid-base approach makes it possible to find the optimum concentration for the makeups of composite materials with specified properties.