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Silane primers

As discussed above, silane primers have been investigated extensively for adhesive bonding of steel substrates and have been shown to be quite effective, but the extent to which these are in current commercial use is not known. [Pg.442]

As an example, an adhesive material could be synthesized according to Equation 4 with an excellent adhesion to glass surface under wet conditions without the necessity to apply silane primers. The network of this adhesive has a glasslike structure and the adhesive power can be optimized by optimizing the content of =SiOR and =SiOH groups (34,30) (Figure 3). ... [Pg.337]

The effect of a multicomponent silane primer on the interphase structure of aluminum/epoxy adhesive joints... [Pg.1]

Oxane bonds between silane coupling agents and glass or metal oxides are rather easily hydrolyzed. For example, the Al-O-Si bond hydrolyzes rapidly in water, and yet very water resistant bonds between polymers and aluminum can be formed through silane primers. [Pg.7]

Similarly, Plueddemann has reported [3c] an optimum silane coupling agent layer thickness of 50-200 A for commercial glass fiber treatment for use in composite materials. On the contrary, optimum adhesion of polypropylene to aluminum was obtained with a silane primer layer between 0.5 and 10 pm thick. In... [Pg.51]

Bonding of urethanes to glass with a hydrophobic silane primer (peel strength, N/cm)... [Pg.111]

The molecular structure of epoxy/metal interphases in the presence of an amino coupling agent was studied by Boerio and co-workers [28] by IR and by XPS. The formation of amide and imide groups in the interphase provided evidence of chemical reaction between the silane primer and the curing agent for epoxy resin. [Pg.221]

The characteristics of silane primer films applied to metal and the use of silane primers to enhance the hydrothermal stability of interfacial bonds to metals have been extensively studied by Boerio and co-workers and are described in detail... [Pg.221]

In all adhesive joints, the interfacial region between the adhesive and the substrate plays an important role in the transfer of stress from one adherend to another [8]. The initial strength and stability of the joint depend on the molecular structure of the interphase after processing and environmental exposure, respectively. Characterization of the molecular structure near the interface is essential to model and, subsequently, to maximize the performance of an adhesive system in a given environment. When deposited on a substrate, the silane primers have a finite thickness and constitute separate phases. If there is interaction between the primer and the adherend surface or adhesive, a new interphase region is formed. This interphase has a molecular structure different from the molecular structure of either of the two primary phases from which it is formed. Thus, it is essential to characterize these interphases thoroughly. [Pg.264]

A-1100 silane primer from Ohio Valley Speciality Chemical (Marietta, Ohio) was used in all APS experiments. Heavy water or deuterium oxide (99.9% pure) was used in all experiments involving APS oligomerization. Heavy water is used to slow down the hydrolysis kinetics and as an NMR reference. Regular water (18 Mfi — cm resistivity at 25°C) was used in all dilutions and elsewhere. [Pg.425]

Abstract—The structure of films formed by a multicomponent silane primer applied to an aluminum adherend and the interactions of this primer with an amine-cured epoxy adhesive were studied using X-ray photoelectron spectroscopy, reflection-absorption infrared spectroscopy, and attenuated total reflectance infrared spectroscopy. The failure in joints prepared from primed adherends occurred extremely close to the adherend surface in a region that contained much interpenetrated primer and epoxy. IR spectra showed evidence of oxidation in the primer. Fracture occurred in a region of interpenetrated primer and adhesive with higher than normal crosslink density. The primer films have a stratified structure that is retained even after curing of the adhesive. [Pg.493]

This work discusses the structure of films formed by a multicomponent silane primer as applied to an aluminum oxide surface as well as the interactions of this primer with the adhesive and oxide to form an interphase region with a distinct composition and properties. The mecanical properties and durability of adhesive joints prepared using this primer system have yet to be evaluated. [Pg.494]

For low- to medium-strength bonds, simple mechanical abrasion is a suitable surface preparation if the substrates are cleaned first. This surface preparation has found success in most ABS applications. A silane primer such as Dow Coming A-4094 or General Electric SS-4101 may be used for higher strength.57 For maximum joint strength, a warm chromic acid etch of the ABS substrate is suggested.58... [Pg.367]

G.L. Witucki, A silane primer Chemistry and applications of alkoxy silanes. /. Coat. TechnoL, 65 (1993) 57-60. [Pg.221]

Modern electron processors offer high speed (high dose-rate) curing of low viscosity liquid coatings so that surface modification of films becomes practicable. A process has been developed for grafting vinyl monomers to polyolefin film surfaces with the aid of functional silane primers using electron initiated polymerization. [Pg.534]

The monomer chosen for this demonstration was acrylonitrile. It Is compatible with the hydrolyzed vinyl benzyl amine silane primer In methanol, and will polymerize and copolymerize with moderate doses of electron beam energy. This study was designated to demonstrate the effectiveness of the new process In radiation grafting of acrylonitrile onto polyolefin films. [Pg.542]

Solutions of the hydrolyzed silane primer In methanol and acrylonitrile were then prepared at acrylonitrilerprlmer ratios of 1, 2, and 3 1. Individual samples of the LOPE film were Immersed In each solution, as well as In the primer above, and Irradiated on both sides (l.e. bilaterally) on the processor at 5 megarads at a 200 kV operating level at O2 concentrations of less than 100 ppm In the process zone. Prior to the runs, the processor was characterized using film dosimeters.(12-13)... [Pg.542]

The physical appearances of all the chemically treated and Irradiated samples indicated that a polymer layer was deposited on the LDPE film surface. The first two samples which had been treated with 1) the vinyl benzylamlne silane primer and 2) the 1 1 volume ratio of acrylonitrile and the vinyl benzyl amine silane primer provided clear samples with a rough surface. The 2 1 and the 3 1 acrylonltrlle/-vlnyl benzyl amine silane treated samples were mottled In appearance, suggesting the formation of regions of polyacrylonitrile homopolymer. [Pg.542]

Figure 8. Dry oxygen permeability of 38 m oriented polypropylene, 135 jX. ffl low density polyethylene and 13 m polyester, treated with varying thicknesses of the silane primer. These data were recorded with a Modern Controls Inc. Oxtran 1000 permeability analyzer. Figure 8. Dry oxygen permeability of 38 m oriented polypropylene, 135 jX. ffl low density polyethylene and 13 m polyester, treated with varying thicknesses of the silane primer. These data were recorded with a Modern Controls Inc. Oxtran 1000 permeability analyzer.
In his test, a thin film of adhesive on a glass microscope slide or a metal coupon is cured and soaked in hot water until the film can be loosened with a razor blade. There is usually a sharp transition between samples that exhibited cohesive failure in the polymer and those which exhibited more of an interfacial failure. Since the diffusion of water into the interface is very rapid in this test, the time to failure is dependent only on interfacial properties and may differ dramatically between unmodified epoxy bonds and epoxy bonds primed with an appropriate silane coupling agent. The time to debond in the hot water for various silane primers differed by several thousandfold when used with a given epoxy. In parallel tests, a thick film of epoxy adhesive on nonsilaned aluminum coupon showed about the same degree of failure after 2h in 70°C water as a silaned joint exhibited after more than 150 days (3600 h) under the same conditions. [Pg.238]

Fig. 3.14. Performance of emery cloth abraded adherends, and the influence of a silane primer, in stressed cleavage tests (Ref. 4). (a) Aromatic amine cured epoxy, (b) Aliphatic amine cured epoxy, (c) Epoxy polysulphide. Fig. 3.14. Performance of emery cloth abraded adherends, and the influence of a silane primer, in stressed cleavage tests (Ref. 4). (a) Aromatic amine cured epoxy, (b) Aliphatic amine cured epoxy, (c) Epoxy polysulphide.

See other pages where Silane primers is mentioned: [Pg.74]    [Pg.404]    [Pg.426]    [Pg.837]    [Pg.114]    [Pg.449]    [Pg.494]    [Pg.495]    [Pg.497]    [Pg.501]    [Pg.505]    [Pg.507]    [Pg.510]    [Pg.512]    [Pg.74]    [Pg.759]    [Pg.74]    [Pg.759]    [Pg.541]    [Pg.686]    [Pg.1581]    [Pg.404]    [Pg.426]    [Pg.86]    [Pg.107]    [Pg.107]    [Pg.172]   
See also in sourсe #XX -- [ Pg.189 ]

See also in sourсe #XX -- [ Pg.310 ]




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