Epoxy pipelining composition and method of manufacture

A cross-linked network polymeric coating on the interior surface of a pipe for carrying potable water, said polymeric coating being produced by in-situ cross-linking polymerization of a polymerizable composition, said polymerizable composition comprising:

• (a) at least one liquid epoxy resin having at least two glycidyl ether groups;
• and
• (b) a liquid curing agent blend comprising:
• (i) an aliphatic polyamine in an amount of about 1-70 mole % based on the liquid curing agent blend;
• (ii) an aliphatic imidazoline derived from fatty acids, said aliphatic imidazoline having a polar moiety and a nonpolar moiety and being present in an amount of about 0.1-40 mole % based on the liquid curing agent blend;
• and
• (iii) an aliphatic amidoamine in an amount of about 5-95 mole % based on the liquid curing agent blend;
• in an amount effective to cure said polymerizable composition to said cross-linked network polymeric coating;
• said cross-linked network polymeric coating having been applied by a turbulent moving steam of air or other gas, or propellant system, said polymerizable composition onto an inner surface of said pipe, thereby causing said polymerizable composition to flow out and wet said inner surface of said pipe and form an uncured pipelining;
• and
• polymerizing said uncured pipelining in situ to form said cross-linked network polymer lining on said inner surface of said pipe, thus forming a lined pipe;
• wherein said polymerizable composition has a pot life of about 1-4 hours, wherein said polymerizable composition further comprises a sufficient amount of a hydrophobic fumed silica thixotropic agent to provide said polymerizable composition with an as-applied mixed viscosity of about 350 to about 1000 centipoise;
• wherein said cross-linked polymeric coating comprises a cross-linked polymer selected from the group consisting of:
• ##STR22## and mixtures thereof wherein n is an integer selected from the group consisting of 0, 1, 2, 3, 4 or mixtures thereof, wherein n' is an integer selected from the group consisting of 0, 1, 2, 3, or mixtures thereof, wherein x is an integer having a value of 0, 1 or mixtures thereof and wherein R R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are saturated hydrocarbons of 1 to 25 carbon atoms and wherein said asterisk indicates primary and secondary amine nitrogens and wherein at least one of said primary and said secondary amine nitrogens marked with said asterisk are crosslinked to an available methylene carbon atom of an available oxirane ring.