An uninflammable film adhesive and an adhesive prepreg based on it

The properties of a composition that can be used as a film adhesive and a binding agent for glass-reinforced plastics are presented. The composition is developed based on brominated epoxy resins and is selfextinguishing. It is shown that the use of adhesives and binding agents based on brominated epoxy resins makes it possible to obtain glass-reinforced plastics with hot-performance capabilities coming close to the properties of structural inflammable materials.     

Synthesis of melamine-glucose resin adhesive

The synthesis of a novel melamine-glucose adhesive that is similar to urea-formaldehyde adhesive is reported in this paper. The conditions of synthesis, such as the initial pH, the quantity of catalyst, the temperature of reaction, the percentage of each reactant and the time of reaction, were optimized by using the orthogonal experimental method.     

General rubber high-strength adhesive

General rubber adhesives with a high strength developed at the All-Russian Scientific Research Institute of Aviation Materials State Research Center of the Russian Federation Federal State Unitary Enterprise and their foreign analogs are described. The main properties of the high-strength elastic adhesive of a new modification provided for gluing the rubbers with metals in the course of vulcanizing are given.     

Synthesis of melamine-glucose resin adhesive

The synthesis of a novel melamine-glucose adhesive that is similar to urea-formaldehyde adhesive is reported in this paper. The conditions of synthesis, such as the initial pH, the quantity of catalyst, the temperature of reaction, the percentage of each reactant and the time of reaction, were optimized by using the orthogonal experimental method.     

Biobased polyurethane adhesive over petroleum based adhesive: Use of renewable resource

This review article is based on the recent trends and development of biobased polyurethane (PU) adhesives from vegetable oil. A detail discussion has been reported about the PU adhesive starting from petroleum based to biobased source. Special attention has been given towards the utilization of castor oil based PU in adhesive technology, due to the wide range of castor oil among all vegetable oil. The appreciable adhesion, mechanical, thermal properties of vegetable oil based PU adhesives were compared with petroleum based PU adhesive, which were utilized to meet the specific application in adhesion industry.     

Cement-polymer adhesive materials

Tile adhesives consisting of Portland cement, fillers, water, and polymer admixtures are described. The key components of tile adhesives are considered. Special attention is paid to polymer components of these adhesives. Information on the largest manufacturers of tile adhesives in Russia is given.     

Effect of fullerenes and gamma-irradiation on the adhesive strength of model adhesive joints

The dependence of the adhesive strength of model glass/binder/glass adhesive compositions cured with aliphatic and aromatic hardeners on the γ-radiation dose was studied. It was shown that the strength of the fullerene-modified binder decreases at low absorbed doses (to 20 kGy), whereas the strength of the composition with the aliphatic binder increases again with an increase in the dose in the range 140–240 kGy, although its does not reach that of the unirradiated composite.     

Elastic properties of thin adhesive interlayers

The effect of the geometrical and physical parameters of the filler (substrate) and the polymer matrix (adhesive) on the modulus of elasticity of discrete models of composites and adhesive compounds is studied. Emphasis is placed on investigation of the elasticity of the layer of adhesive (binding agent) positioned between hard substrates. Elasticity moduli of the epoxy polymer in the state of a thin layer and in the block (in the form of a free rod) upon their simultaneous fabrication in the process of polymer curing are compared. The results of theoretical solution of the problem of the dependence of the interlayer elasticity modulus and the layered composite on thickness, Poisson’s ratios, elasticity moduli, and other parameters of the adhesive and the substrate are presented. The solution in the closed form was obtained owing to the application of the contact-layer method.     

The influence of the EP-0234 adhesive primer on the properties of adhesive joints made using VK-50 phenolic–rubber adhesive

Results of testing adhesive joints of D19AT aluminum alloy made with VK-50 adhesive with the use of the EP-0234 primer are presented. It was shown that the EP-0234 primer not only increases the period between the operations of anodizing and bonding of aluminum alloy samples, but also improves the strength characteristics of adhesive joints under the conditions of exposure to water, artificial tropical climate, high temperature, and overloads.     

Predicting the endurance of adhesive joints

The paper studies the causes of loss of efficiency of designs with adhesive joints and models for determining their endurance and probability of failure-free operation upon gradual and sudden failure. For the model of gradual failure, we propose a technique for assessing the maximum allowable value of the output parameter, for which the shear strength is most often used, and the rate of degradation processes of adhesive materials. Examples of calculating the endurance are given.     

Skin effect in adhesive solutions

Summary The membranometric method of quantitatively studying skin formation on surfaces of colloidal solutions developed byWo. Ostwald was adopted with slight modifications by the authors in their studies on adhesive solutions. The time of flow through a vertical capillary was found to vary with the time of contact and concentration, which may be attributed to any changes in viscosity during the period and formation of a skin. By running a control, the viscosity effect was eliminated. The position of the meniscus when sucked to a definite height and released, at different periods, is plotted as a function of time. It is suggested that the difference in the area between the curves for control and different periods of contact can be taken as a measure of the strength of skin formation. Results for gelatin solutions are given. With 2 figures in 3 details and 3 tables     

Effect of organosilicon additives on surface segregation of components of epoxyurethane adhesive compositions and their adhesive behavior

The effect of organosilicon additives of various molecular weights—phenyltributyleneglucoxysilan (PBS) and phenyltrioligooxypropyleneglycoxysilan (KMS1052)—on the surface segregation of components of epoxyurethane adhesive compositions and their adhesive behavior is studied It is shown that the surface concentration of components differs considerably from that of the volume as a result of their selective redistribution under the influence of a solid surface. The dependence of the surface segregation of components of epoxyurethane compositions and their adhesive behavior on the concentration of the mentioned additives exhibits an extreme behavior (the effect of small additives).     

Deflected mode simulation of adhesive joints

The basic principles of the application of a statistical modeling technique (the Monte Carlo method) to analyze the value of maximal strain in an adhesive joint performed using adhesives based on epoxy oligomers and amine curing agents are given. Calculation algorithms that allow for multifactor investigations are proposed. The model structure is formed based on an analysis of the cause-and-effect relationships in the technological and operation factors, and input parameters are determined using statistical methods. An example of deflected mode analysis for an adhesive joint is given.     

A reversible water-based electrostatic adhesive

Commercial adhesives typically fall into two categories: structural or pressure sensitive. Structural glues rely on covalent bonds formed during curing and provide high tensile strength whilst pressure-sensitive adhesives use physical bonding to provide weaker adhesion, but with considerable convenience for the user. Here, a new class of adhesive is presented that is also reversible, with a bond strength intermediate between those of pressure-sensitive and structural adhesives. Complementary water-based formulations incorporating oppositely charged polyelectrolytes form electrostatic bonds that may be reversed through immersion in a low or high pH aqueous environment. This electrostatic adhesive has the advantageous property that it exhibits good adhesion to low-energy surfaces such as polypropylene. Furthermore, it is produced by the emulsion copolymerization of commodity materials, styrene and butyl acrylate, which makes it inexpensive and opens the possibility of industrial production. Bio-based materials have been also integrated into the formulations to further increase sustainability. Moreover, unlike other water-based glues, adhesion does not significantly degrade in humid environments. Because such electrostatic adhesives do not require mechanical detachment, they are appropriate for the large-scale recycling of, e.g., bottle labels or food packaging. The adhesive is also suitable for dismantling components in areas as varied as automotive parts and electronics.     

Materials with bitumen-polymer adhesive layer

Materials composed of polyethylene or poly(vinyl chloride) tapes and Transpor bitumen-polymer mastic are described as a means for the anticorrosive protection of steel underground oil pipelines. A combined coating composed of bitumen-polymer primer, bitumen-polymer mastic, and shrinkable film is proposed for the major repair of oil pipelines.     

Noncombustible adhesive compositions based on brominated epoxide resins for production of structural film adhesives and adhesive prepregs

This paper presents a composition developed for use both as a film adhesive with a working temperature up to 150°C and as a binder for production of fiberglass with a working temperature up to 120°C. The composition is autoextinguishing and contains bromated epoxy resins. It is shown that the strength property indices of the fiberglass bound with the created composition are up to those for modern structural materials.     

Deformation and adhesive contact of elastomeric membranes

We have developed a highly sensitive inflation technique for probing adhesive interactions between soft materials. In this method, an elastomeric membrane is placed across a cylindrical glass tube and is pressurized into contact with a substrate. The adhesive interaction between the membrane and the substrate is obtained from the angle of contact, which is determined indirectly from the measured contact radius and applied pressure. An analysis of the membrane profile based on the numerical solution of the axisymmetric Laplace equation is developed. In a nonadhesive situation, where the membrane contact angle is known to be zero, the analysis is used to obtain the relationship between the membrane deformation and the biaxial membrane strain. Linearization of the governing equations is used to develop an analytic solution for the contact angle and energy release rate, making a connection to existing, more restrictive analyses of this problem. Results from three different types of membranes are presented as illustrative applications of the method. The substrate in these experiments is the gold electrode surface of a quartz crystal resonator, and the effect of membrane contact on the crystal resonance is summarized briefly. Adhesive interactions between the membranes are minimized in most cases by adding a grafted polyethylene glycol brush to one or both of the contacting surfaces. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 3361–3374, 2007     

Oscillatory loading of a viscoelastic adhesive contact

The cycle of loading and unloading of a spherically-tipped probe against an adhesive, viscoelastic plane specimen is studied by numerical integration of the relations between crack speed and apparent surface energy previously found for a linear 3-element viscoelastic solid with a Maugis-Dugdale law of force across the crack. It is found that even when the rate of loading is so slow that the loading and unloading curves almost coincide, suggesting purely elastic behaviour, the pull-off force can be appreciably greater than the elastic (JKR) value. When the normal force is modulated with a small amplitude sinusoidal variation during unloading--in order to find the contact stiffness--the contact radius barely changes, and the stiffness is close to that for a rigid flat punch instead of having the expected JKR value.     

Asymptotic method in adhesive mechanics

It has been stated that the asymptotical approach, which takes into account the relative contribution of various factors in the intense-deformed conditions of adhesive compounds, which allows one use corresponding small parameters. With this approach, it is possible not only to consider heterogeneity of the intense-deformation condition of adhesive connections, but also to estimate the role of singularities that arise on the border adhesive with a substratum at angular points. Unlike the contact-layer method, the asymptotic method relies on the analysis and use of singularity characteristics, which represents an alternative criterion for estimating adhesive interactions.