The role of adhesion in the mechanical properties of filled polymer composites

Bifunctional coupling agents for improved mechanical properties in fiberglass/polyethylene composites

“…Creep behavior drops dramatically when a silane-coupling agent is present. Harding and Berg 23 suggest that yield strength is the property most reflective of interfacial strength. They have determined that it is the penetration of the silane organofunctional group into the polymer matrix, not the thickness of the silane coupling agent on the glass surface, that provides enhancement in adhesion and increased yield strength in aminosilane/polyvinylbutyrate composites.…”

“Fundamental” and “practical” adhesion in polymer-fiber systems

“…(6) that any surface should be characterized, as a minimum, by three parameters: the dispersion part of the surface free energy yd and two coefficients characterizing the basicity K s and acidity K A of the surface, i.e., its ability to act as an electron donor and acceptor, respectively. The values K u and K A are determined using the inverse gas chromatography technique [13,14,23,24]. At present, these parameters are known for many polymers and fibers and can be found in the literature.…”

“…It is important to mention that an increase in the donor capability of the r~inforcement surface (when the matrix has acceptor properties), and vice versa, results in an increase in both fund,mental and practical adhesion [13,14,24].…”

“…One of them is extrapolation of the experimentally measured adhesive strength ~ (as a function of the embedded length) to zero embedded length [24]. In the second approach, a model is used which takes into account beth the elastic and thermal stresses in the specimen [34].…”

Activation of bifunctional coupling agents in fiberglass/polyethylene composites by electron beam

“…The presence of these surface-active compounds allows the two chemically dissimilar materials, fiberglass and polyethylene, to be coupled together, so that the resulting composites display increased hardness and tensile modulus, and generally a range of properties that extend beyond those exhibited by unaltered polyethylene. Covalent bonding between high-density polyethylene (HDPE) and glass spheres with a silane coupling agent has been shown to have a significant influence on the stress/strain behavior [1][2][3] and creep properties of these composites at room temperature. As glass is added, the modulus drops, but increases again as the coupling agent is added.…”