LIGHTWEIGHT POLYMER CONCRETE COMPOSITION
A lightweight foamed polymer concrete admixture for use in fabricating building components, the polymer concrete comprising a mixture of a polyol, an isocyanate, an aggregate, and water, wherein once mixed, the mixture releases carbon dioxide gas creating a foamed mixture that may be shaped to form a building component such as, but not limited to, lap siding, shake siding, trim boards, stone and stucco sheeting.
1 . A polymer concrete composition useful for fabricating lightweight building products, the polymer concrete composition comprising;
(a) aggregate in an amount in the range from about 50 to 90% by weight of the polymer concrete composition;
(b) polyol in an amount in the range from about 10 to 20% by weight of the polymer concrete composition;
(c) isocyanate in an amount in the range from about 5 to 15% by weight of the polymer concrete composition; and
(d) water in an amount of at least 0.1% by weight of the polymer concrete composition, wherein the sum of the components (a) through (d) add up to 100 weight % and after the product is cured in a continuous belt mold the polymer concrete exhibits a density of from about 0.7 to 1.5 g/cm 3 and a flexural strength of from about 0.6 to 1.0 Mpa.
2 . The polymer concrete composition of claim 1 , wherein fibers are added to the admixture in the range of about 1 to 5%.
3 . The polymer concrete composition of claim 2 , wherein chopped glass fibers preferably about one-quarter inch in length are added to the admixture.
4 . The polymer concrete composition of claim 2 , wherein milled glass fibers preferably about one-sixteenth inch in length are added to the admixture.
5 . The polymer concrete composition of claim 2 , wherein cellulose fibers are added to the admixture.
6 . The polymer concrete composition of claim 2 , wherein cotton fibers preferably about 4 mm in length are added to the admixture.
7 . The polymer concrete composition of claim 1 , wherein the cured building product is covered with a cap comprised of polyvinyl chloride in a thickness ranging from about 0.003 to 0.005 inches.
8 . The polymer concrete composition of claim 1 , wherein the cured building product is covered with a cap comprised of acrylonitrile styrene acrylate in a thickness ranging from about 0.003 to 0.005 inches.
9 . The polymer concrete composition of claim 1 , wherein the composition is cured in a mold for 2 hours at 100° C. and then demolded and cured for at least 2 hours at a temperature between 60 and 120° C.