Thermosetting castable and curable polyurethane-urea polymers having improved flow and end-waste characteristics for insulating thermal barriers

A thermosetting castable and curable polyurethane-urea polymer having improved flow and end-waste characteristics, suitable for pouring into a channel in an aluminum extrusion to provide a thermal barrier upon curing of the polymer and debridgement of the channel, consisting essentially of the following inter-reacted components:

• A) a polyisocyanate having a functionality of at least about 2;
• B) at least one polyether diol or polyol having a molecular weight between about 2000 and about 6000 and an OH-functionality between about 2 and about 4;
• C) a polyether diol or polyol having a molecular weight of 300 to less than 2000 and an OH-functionality between about 2 and about 4;
• D) one or more glycols having a molecular weight between about 50 and 250 and an OH-functionality between about 1.8 and about 2.2;
• E) a polyester diol or polyol having a molecular weight between about 250 and 1000 and an OH-functionality of about 1.5 to about 4;
• F) a polyamine having a molecular weight between about 50 and about 4000 and an amine functionality of about 2 to about 4;
• and
• said constituent diols and polyols being in the proportion of 0 to about 85 percent by weight of B), about 5 to about 90 percent by weight of C), 0 to about 25 percent by weight of D), 0 to about 30 percent by weight of E), and about 2 to about 15 percent by weight of F), per 100 percent by weight of all diol and polyol and amine components;
• the combined percentage of B) and C) being about 40 to about 90 percent by weight;
• G) an effective polyurethane-catalyzing amount of a urethane catalyst;
• and
• the isocyanate component A) and combined diol and polyol and amine components B), C), D), E), and F) being in proportions so as to provide an NCO ratio to the active hydrogen in all diol, polyol, and amine components of at least about 1:1,
• with the proviso that, when all three of B), D), and E) are each present at less than 5% by weight, then the molecular weight of C) is about 1500 or less,
• the polymer having the following characteristics:
• a flow time not greater than about six (6) seconds when poured into an aluminum channel 8 feet long, 1/4 inch wide, and 1/2 inch deep at a temperature of approximately 77.degree. F.,
• a gel time not greater than about five minutes,
• and, when cured, a notched IZOD impact strength (PLI) greater than 0.5,
• a tensile strength (PSI) greater than 500,
• an elongation greater than 10%,
• and an at least 65 shore A hardness using a Rex durometer.