Curing agents anhydride

Anhydride curing agents - corrosive, severe sensitizers dusts may be sensitizers high toxicity... [Pg.145]

The present study, by contrast, deals with toughening of cycloaliphatic type epoxies with anhydride curing agents normally used in industrial applications. In addition to developing mechanical property data, the morphological characteristics were also studied. [Pg.542]

The calculation of stoichiometric quantities of curing agents differs for amine and anhydride curing agents, and these are discussed below. The stoichiometric calculation has no... [Pg.38]

Procedure for calculating the stoichiometric quantity of anhydride curing agent... [Pg.40]

After the primary amines, acid anhydrides are the next most important class of curing agents, although these are not used as often in adhesive systems as they are in casting compounds, encapsulants, molding compounds, etc. More information on anhydride curing agents can be found in Chap. 5. [Pg.41]

FIGURE 5.6 Chemical structures of acid anhydride curing agents. [Pg.100]

HHPA is generally used in a concentration between 55 and 80 pph depending on the nature of the epoxy resin. The viscosity is generally about 200 cP at 40°C when mixed with a DGEBA epoxy resin. A typical cure schedule for a 0.5 to 2 percent BDMA catalyzed system is 2 h at 80°C plus 1 h at 200°C. Typical of all the anhydride curing agents, the cured epoxy will demonstrate high heat distortion temperatures and excellent chemical resistance. [Pg.102]

Phthalic anhydride (PA) and its derivatives are among the most common anhydride curing agents. Table 12.6 describes an anhydride cured epoxy adhesive that is accelerated with... [Pg.232]

Since the reaction between an epoxy resin and an acid anhydride curing agent also produces an ester linkage, anhydride cured epoxies have poorer hydrolytic stability than do... [Pg.327]

Amine curing agents for epoxies are poor in oxidizing acids. Anhydride curing agents are poor in caustics. [Pg.336]

Liquid epoxy resins are stable for long periods at room temperature. Resins that are cut with diluent or solvent should be stored in tight containers to prevent loss of volatiles. Also, certain resins and curing agents (e.g., anhydride curing agents) can be degraded by exposure... [Pg.392]

To improve high temperature stability over amine cured systems and to give better physical and electrical properties above their heat distortion temperatures, it has been general practice in epoxy resin systems to use anhydride curing agents with DGEBA epoxy resins (8 ). Most anhydride formulations require elevated-temperature cures with the ultimate properties dependent on postcures at temperatures of 150 C or higher. [Pg.48]

Carboxylic acid and anhydride curing agents are used to a lesser extent in aerospace applications as compared to the amines which have mechanical properties and cure conditions that can be tailored to a wider variety of specific applications. Anhydrides tend to be somewhat brittle but offer useful service as high as 250 °C with novolac-type epoxy resins. In addition, the aliphatic dicarboxylic acid anhydrides give tough and sometimes flexible properties which are useful in encapsulation applications. [Pg.561]

Ancadride . [Pacific Am ] Anhydrides curing agent intermediate aOtyds, fdastidzers, insect repdlents, rust inhibitors, hardener in qpoxy resins. [Pg.26]

Curebond. [Poly Organix] Anhydride curing agents. [Pg.92]

Lindride. [Lindau Chems] Anhydride curing agent to epoxy resins. [Pg.209]

Properties of a composition consisting of a standard bisphenol A/ECH epoxy resin with 20% cyanoethylated ACEC (XLVI) and an acid anhydride curing agent exhibit a considerably elevated heat resistance. [Pg.82]

FIGURE 4.35 Anhydride curing agents, (a) Maleic anhydride, (b) Dodecenylsuccinic anhydride, (c) Phthahc anhydride, (d) Hexahydrophthalic anhydride, (e) Pyromellitic anhydride, (f) Trimellitic anhydride, (g) Nadic methyl anhydride, (h) Chlorendic anhydride. [Pg.501]

Phthalic anhydride is the cheapest anhydride curing agent, but it has the disadvantage of being rather difhcult to mix with the resin. Liquid anhydrides (e.g., dodecenylsuccinic anhydride and nadic methyl anhydride), low-melting anhydrides (e.g., hexahydrophthalic anhydride), and eutectic mixtures are more easily incorporated into the resin. Since maleic anhydride produces brittle products, it is seldom used by itself and is used as a secondary hardener in admixture with other anhydrides. Dodecenylsuccinic anhydride imparts flexibility into the casting, whereas chlorendic anhydride confers flame resistance. [Pg.502]

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