Adhesive compostion

An adhesive composition comprising:

• a first part comprising
• about 10 to about 50 wt % of an epoxy compound,
• about 20 to about 70 wt % of an epoxy novolac,
• about 5 to about 20 wt % of an epoxy-based reactive diluent, and
• about 10 to about 40 wt % of first part additives,
• based on the total weight of the first part;
• and
• a second part comprising
• less than about 10 wt % of a hydroxyaromatic solvent,
• about 10 to about 30 wt % of a Mannich base, and
• about 0.1 to about 10 wt % of a tertiary amine, and
• about 60 to about 90 wt % of second part additives,
• based on the total weight of the second part,
• the first and second parts being present in a volume ratio of about 0.8:1 to about 1.2:1.

A method of forming an adhesive layer comprising:

• combining a first part and a second part of an adhesive composition, the first part comprising:
• about 15 to about 60 wt % of an epoxy compound,
• about 35 to about 80 wt % of an epoxy novolac, and
• about 5 to about 25 wt % of an epoxy-based reactive diluent
• based on the total weight of epoxy compound, epoxy novolac, and reactive diluent;
• and
• the second part comprising
• less than about 20 wt % of a hydroxyaromatic solvent,
• about 80 to about 99 wt % of a Mannich base, and
• about 1 to about 20 wt % of a tertiary amine,
• based on the total weight of hydroxyaromatic solvent, Mannich base, and tertiary amine,
• the first and second parts being present in a volume ratio of about 0.8:1 to about 1.2:1;
• and
• applying the adhesive composition to a surface.

A method of making an epoxy adhesive, comprising:

• forming a first combination by combining until homogeneous:
• about 23.50 wt % of bisphenol A diepoxy,
• about 43.01 wt % of epoxy novolac,
• about 9.81 wt % of 2-ethyl-2-hydroxymethyl-1,3-propanediol copolymer with chloromethyloxirane,
• about 2.51 wt % of fumed silica suspension agent,
• about 0.10 wt % of titanium dioxide,
• about 5.27 wt % of silica sand having a mesh size greater than 50, and
• about 15.80 wt % of silica sand having a mesh size of less than 25;
• forming a second composition by combining until homogeneous:
• about 24.40 wt % of 1,3-(N,N-dimethylaminomethyl) benzene,
• about 2.80 wt % of tertiary amine hardener,
• about 2.80 wt % of benzyl alcohol,
• about 0.90 wt % of fumed silica suspension agent,
• about 0.02 wt % of carbon black,
• about 17.50 wt % of fine silica sand of greater than 50 mesh, and
• about 52.48 wt % of coarse silica sand of less than 25 mesh;
• and
• combining the first and second compositions in a ratio of about 1:1 by volume.