Epoxies solvent resistence

A number of amorphous thermoplastics are presently employed as matrices in long fiber composites, including polyethersulfone (PES), polysulfone (PSU), and polyetherimide (PEI). AH offer superior resistance to impact loading and higher interlaminar fracture toughnesses than do most epoxies. However, the amorphous nature of such polymers results in a lower solvent resistance, clearly a limitation if composites based on such polymers are to be used in aggressive environments. 

Furane resins are superior to polyesters and epoxies for resistance to ketones, chlorinated solvents and carbon disulfide. However, as they are... 

In comparison with epoxies, the correctly formulated urethane can possess considerably superior gloss retention and flexibility. They also form a film so hard and solvent resistant that they can be used as anti-graffiti coating. The graffiti can be removed with solvent without damaging the urethane. Since these materials give off toxic fumes in a fire it is preferable that they are not used in confined spaces. 

These data are consistent with the observation O) that increased crosslinking (i.e., epoxy resins with lower EEW s) will result in a decreased propensity for the cured polymer to absorb solvents. Thus, the solvent resistence of an organic coating can be controlled by the formulator via variations in the molecular weight between crosslinks. 

Phenolic, epoxy, urea, melamine, and polyester (alkyd) polymers are cross-linked (thermoset) plastics. They are solvent-resistant and are not softened by heat. Unlike the thermoplastic step reaction polymers, which are produced by the condensation of two difunctional reactants, these network polymers are produced from reactants at least one of which has a degree of functionality higher than two. 

Clear polyester sheet stock and rods are available13 and, like reinforced polyester plastic, may be drilled, sawed, and machined. This clear plasic is harder than poly(methyl methacrylate) and much more solvent resistant than either po-lyfmethyl methacrylate) or polystyrene. As with all thermosetting plastics, it may not be heat-formed or solvent-bonded. However, bonding with epoxy cements is satisfactory. This plastic is claimed to give continuous service at 80°C and intermittent service up to 150°C. 

Bisphenol F epoxy resins are produced by condensing phenol with formaldehyde, resulting in a mixture of isomers and higher-MW condensation products. Bisphenol F epoxy resins have lower viscosity then DGEB A epoxy resins for the same molecular weight (or number of repeating units n). Cured bisphenol F epoxy resins also have increased solvent resistance. 

High-build abrasion-resistant epoxy Acid-resistant epoxy High-build, recoatable epoxy Solvent-free epoxy 1... 

These include humidity and solvent resistance of epoxy-acrylates,... 

Solid adducts Isolated amine products, in particular, offer advantages such as low colour, low free amine content and low irritation potential they also provide non-yellowing, bloom-free films with good chemical and solvent resistance Amine adducts solvent-based, two-pack coatings, e.g. primers, finishes and coal tar epoxy coatings... 

Polyester and Vinyl Ester Mortars These two mortars, of which there are many types, are suitable for a pH range of about 0-11 and a continuous service temperature of 225°-230°F. The two related resins, which complement the epoxy resins, resist dilute and concentrated acids and weak alkalies. Their resistance to acid bleaches such as chlorine dioxide and to oxidizing acids such as nitric and chromic is superior to that of other resinous mortars, and they are excellent in acetic acid and related esters. However, polyester and vinyl ester mortars are the poorest resin mortars in other organic chemical exposures including solvents in general. Such mortars are widely used in paper mills and are suitable with acid brick or ceramic tile in the lower temperature zones of mildly acidic utility FGD systems. 

STM tips operated in electrochemistry environments have to be coated with wax or with a solvent resistant polymer (e.g. nail varnish, epoxy) leaving the tip apex free. 

SOLVENT RESISTANCE OF AROMATIC AMINE-CURED HYDANTOIN EPOXY RESIN... 

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