Process for lining canals, ditches and pipes with a non-sagging polyurethane/geofabric composite

A process for lining an overhead ceiling of a canal or pipe, comprising applying a non-sagging polyurethane composition onto an overhead surface or ceiling of a canal or pipe, contacting a geofabric with the non-sagging polyurethane composition in a manner such that the geofabric becomes impregnated with the non-sagging polyurethane composition, allowing the polyurethane to cure thereby forming a polyurethane/geofabric composite, the non-sagging polyurethane composition comprising a reaction product of:

• a) a liquid polyisocyanate component;
• b) 80-98% by weight, based on total weight of b) and c), of a liquid high molecular weight isocyanate reactive component comprising one or more hydroxyl group containing compounds having from about 2 to about 6 hydroxyl groups and a number average molecular weight of at least 250 and, 0-10% by weight, based on total weight of b), of a low molecular weight diol or triol having a hydroxy equivalent weight of from about 31 to 99;
• c) 2-20% by weight, based on total weight of b) and c) of an isocyanate reactive compound containing at least two amine groups;
• optionally,
• d) one or more fillers in an amount of up to 80% by weight based upon the total weight of the polyurethane-forming mixture;
• and
• optionally,
• e) a catalyst.

A process for lining a ditch, canal, or pipe having a surface with a surface angle equal to or greater than 90°, comprising applying a non-sagging polyurethane composition onto the surface of the ditch, canal and/or pipe, contacting a geofabric with the non-sagging polyurethane composition in a manner such that the geofabric becomes impregnated with the non-sagging polyurethane composition, and allowing the polyurethane to cure thereby forming a polyurethane/geofabric composite, the non-sagging polyurethane composition comprising a reaction product of:

• a) a liquid polyisocyanate component;
• b) 80-98% by weight, based on total weight of b) and c), of a liquid isocyanate reactive component comprising one or more hydroxyl group containing compounds having from about 2 to about 6 hydroxyl groups and a number average molecular weight of at least 250 and, 0-10% by weight, based on total weight of b), of a low molecular weight diol or triol having a hydroxy equivalent weight of from about 31 to 99;
• c) 2-20% by weight, based on total weight of b) and c), of an isocyanate reactive compound containing at least two amine groups;
• optionally,
• d) one or more fillers in an amount of up to 80% by weight based upon the total weight of the polyurethane composition;
• and
• optionally,
• e) a catalyst.

A process for lining a concave ditch, canal, or pipe, comprising applying a non-sagging polyurethane composition onto a concave surface of the ditch, canal and/or pipe, contacting a geofabric with the non-sagging polyurethane composition in a manner such that the geofabric becomes impregnated with the non-sagging polyurethane composition and allowing the polyurethane composition to cure, thereby forming a polyurethane/geofabric composite, the non-sagging polyurethane composition comprising a reaction product of:

• a) a liquid polyisocyanate component;
• b) 80-98% by weight, based on total weight of b) and c), of a liquid high molecular weight isocyanate reactive component comprising one or more hydroxyl group containing compounds having from about 2 to about 6 hydroxyl groups and a number average molecular weight of at least 250 and, 0-10% by weight, based on total weight of b), of a low molecular weight diol or trio having a hydroxy equivalent weight of from about 31 to 99;
• c) 2-20% by weight, based on total weight of b) and c), of an isocyanate reactive compound containing at least two amine groups;
• optionally
• d) one or more fillers in an amount of up to 80% by weight based upon the total weight of the polyurethane-forming mixture;
• and
• optionally
• e) a catalyst.

A process for lining a cracked or broken ditch, canal, or pipe, comprising applying a non-sagging polyurethane composition onto a cracked or broken surface of the ditch, canal or pipe, contacting a geofabric with the non-sagging polyurethane composition in a manner such that the geofabric becomes impregnated with the non-sagging polyurethane composition, and allowing the polyurethane to cure thereby forming a polyurethane/geofabric composite, the non-sagging polyurethane composition comprising a reaction product of:

• a) a liquid polyisocyanate component;
• b) 80-98% by weight, based on total weight of by and c), of a liquid isocyanate reactive component comprising one or more hydroxyl group containing compounds having from about 2 to about 6 hydroxyl groups and a number average molecular weight of at least 250 and, 0-10% by weight, based on total weight of b), of a low molecular weight diol or triol having a hydroxy equivalent weight of from about 31 to 99;
• c) 2-20% by weight, based on total weight of b) and c), of an isocyanate reactive compound containing at least two amine groups;
• optionally,
• d) one or more fillers in an amount of up to 80% by weight based upon the total weight of the polyurethane composition;
• and
• optionally,
• e) a catalyst.