Effects of an adhesion promoter on the debond resistance of a metal-polymethylmethacrylate interface

Abstract

Debonding and premature failure of prostheticpolymethylmethacrylate interfaces have been shown to be exacerbated by exposure to physiological environment. In efforts to counteract these hydrolytic degradation effects, two clinically relevant Co-Cr-Mo surface morphologies were treated with an organosilane adhesion promoter (gamma-methacyloxypropyltrimethoxy) before interface bonding. Samples were quantitatively characterized in terms of the adhesion (fracture) and subcritical debond growth-rate (fatigue) behavior of the interface. The steady-state interface debond resistance, Gss (J/m2), was shown to increase with application of the silane pretreatment both in air (20 degrees C, 45% relative humidity) and simulated physiological environment (37 degrees C, Ringer's). Similarly, positive shifts in the subcritical debond threshold, deltaG(TH), values are observed for silane pretreated interfaces. A shift in the debond path from primarily adhesive failure in untreated surfaces to cohesive failure between the silane layer and bulk polymethylmethacrylate for silane treated surfaces was observed. Silane pretreatment of Co-Cr-Mo surfaces was shown to effectively limit the degree of the environmental degradation. General insights to the effects of surface roughness, chemical enhancement, and the environmental effects on the thermodynamics at the interface and resulting debond behavior are discussed.

Adhesion enhancement of steel fibers to acrylic bone cement through a silane coupling agent

“…10). This is in accordance with recent findings that failure occurs within the silane layer 20. Based on the bond‐strength values of the various bonds at the SS–acrylic interface in the silanated samples (i.e., SiC, 451 kJ/mol; CC, 607 kJ/mol; CO, 1077 kJ/mol; and SiO, 800 kJ/mol),26 failure is predicted to occur between the Si and C atoms of the organosilane.…”

“…The bonding between the reinforcements (with the exception of PMMA fibers) and the acrylic bone cement is extremely poor, as observed by failure at the reinforcement–cement interface 14, 18, 19. The improvement in adhesion between the acrylic matrix and the reinforcement through the use of a coupling agent (silane bonding agents) increases the mechanical properties of acrylic bone cements 20, 21. These organosilane agents improve bonding by the formation of strong covalent bonds in place of weak secondary bonds (van der Waals) between the acrylic matrix and reinforcements 21–23.…”

Orthopaedic Prostheses

“…Both the metal-cement [Ohashi et al, 2001] and the bone-cement [Gough and Downes, 2001] interfaces are vulnerable to debonding. The physiological environment is found to be highly destructive to the metal-cement bond where destructive hydrolytic processes commonly occur [Ohashi et al, 2001]. An adhesion promoter can be added to the PMMA cement to try to prolong adhesion between metal and PMMA [Ohashi et al, 2001].…”

“…The physiological environment is found to be highly destructive to the metal-cement bond where destructive hydrolytic processes commonly occur [Ohashi et al, 2001]. An adhesion promoter can be added to the PMMA cement to try to prolong adhesion between metal and PMMA [Ohashi et al, 2001]. Another means of improving PMMA adhesion to the metal is to pretreat the metal surface of the implant with a silica/silane coating [Fischer et al, 2001].…”

The Role of Nanoscale Confinement of Adhesion Promoting Molecules on the Adhesion and Resistance to Moisture Attack at the Polymer/Silicon Nitride Interface

“…While the majority of these efforts have studied organosilane molecules as primers, confined to the substarte surface, there exist a few instances where their use as additives, blended into the polymer layer, has been explored [4][5]. Even fewer studies, however, have addressed organosilane use with respect to the issues of subcritical debonding and threshold or near-threshold debond growth [6][7][8]. The latter is of considerable importance for the materials system under consideration, which exhibits anomalous behavior in the near-threshold region [9].…”