Rheological Properties Of Adhesives Research Articles

Rheological properties of adhesives based on modified phenol-formaldehyde oligomers

Rheological properties of cured adhesives based on phenol-formaldehyde oligomer modified by various amounts of furan oligomer have been determined. Modification of phenol formaldehyde resin by furan oligomer has been found to result in a firmer and more rigid adhesive line in the wood chipboard structure.

Application and Study of Reactive Polyacrylate Microgel in Pigment Paint of Printed Fabric

Polyacrylate microgel emulsion was prepared by emulsion polymerization using styrene, α-n-butyl acrylate and methyl methacrylate as monomer, polyoxyethylene octylphenol ether (TX-30) and sodium dodecyl sulfate(SDS) as combine emulsifier, divinyl benzene and ammonium persulfate (APS) as initiator，respectively. The prepared microgel was analyzed by a variety of measurment methods, such as Fourier transform infrared spectroscopy and transmission electron microscopy. The effect of microgel on the rheological properties of adhesives, leveling, mechanical properties and pigment printing performance was studied. The rhelogy and the color fastness of the pigment printing binder of printed fabrics were measured by rheometer and friction color fastness test instruments, respectively. At the same time, the mechanical properties of the adhesive film was measured by strength tester. The results show that the thixotropy, leveling and mechanical properties of adhesive printing binder and pringting quality of coating fabrics were improved when the microgel was added.

Effect of the rheological properties of industrial hot-melt and pressure-sensitive adhesives on the peel behavior

Three factors govern the adhesion properties of hot-melt and pressure-sensitive adhesives: (1) thermodynamic interfacial properties (Dupré adhesion energy); (2) interfacial losses due to specific interactions; and (3) viscoelastic losses in the bulk related to the rheological properties of the adhesive. In the present paper, we focus on the main factor in the adhesion properties, which is the viscoelastic factor. We extend in this paper the results obtained on a series of model adhesives to the case of industrial formulations: one SIS triblock copolymer-based PSA formulation and one EVA copolymer-based hot-melt formulation. After studying the rheological properties of these adhesives over a wide frequency range using time-temperature equivalence, we present data obtained on peel tests at various temperatures. As with model adhesives, the peel rate-temperature equivalence leads to the same shift factors as rheology. The experiments demonstrate that there is a one-to-one relationship between the cohesive fracture domain and the terminal region of relaxation exhibited in rheological testing. The first interfacial fracture mode is related to the rubbery plateau, and the brittle interfacial fracture mode observed at high peel rates to the glassy behavior exhibited at very high frequencies in rheological measurements.

Surface roughness and rheological properties of adhesives as factors determining optimal thickness of glue line

The effect of the thickness of the glue line on the bond strength of construction materials is examined and the dependence of the optimal thickness of the glue line on surface roughness and glue viscosity is shown. The effect of surface roughness on strength and durability of adhesive joints is explained on the basis of a molecular mechanism of interaction of the glue with the surface roughnesses and an approximate expression is derived for the depth of penetration of the glue into microcavities of the surface as a function of the geometric parameters of the microcavities, specific pressure, and surface tension of the interface with the air.