Filled polyurethane or polyisocyanurate foam and method of making same

Abstract

Polyurethane or polyisocyanurate foam stock and methods of manufacturing are described herein. The foam stock can include (a) a polyurethane or polyisocyanurate formed by the reaction of (i) one or more isocyanates selected from the group consisting of diisocyanates, polyisocyanates, and mixtures thereof, and (ii) one or more polyols; and (b) a filler present in an amount from greater than 50% to 90% by weight, based on the total weight of the foam stock. The density of the foam stock can be from 10 lb/ft.sup.3 to 35 lb/ft.sup.3. The flexural strength of the foam stock can be at least 100 psi. The resulting foam stock can be used to produce polyurethane or polyisocyanurate foam to be used in composite panels.

Claims

1. A composite panel comprising: a foam stock comprising a recycled filler, wherein the recycled filler is present in an amount equal to or greater than 10% by weight, based on the total weight of the foam stock; and a cementitious coating on the foam stock; wherein the foam stock has a density of 10 lb/ft.sup.3 to 35 lb/ft.sup.3; and wherein a compressive strength of the foam stock is equal to or greater than 100 psi.

2. The composite panel of claim 1, wherein a thickness of the composite panel is equal to or less than 2 inches.

3. The composite panel of claim 1, wherein a thickness of the cementitious coating is equal to or less than 0.5 inches.

4. The composite panel of claim 1, wherein a width of the composite panel is 2 feet to 4 feet.

5. The composite panel of claim 1, wherein the foam stock comprises polyurethane in an amount of 1% to 50% by weight, based on the total weight of the foam stock.

6. The composite panel of claim 1, wherein the recycled filler is present in an amount equal to or greater than 30% by weight, based on the total weight of the foam stock.

7. The composite panel of claim 1, wherein the foam stock, the cementitious coating, or both further comprises a plurality of fibers dispersed therein.

8. The composite panel of claim 7, wherein the fibers are present in the foam stock, the cementitious coating, or both in an amount of 0.25% to 15% by weight, based on the total weight of the respective foam stock, the cementitious coating, or both.

9. The composite panel of claim 7, wherein an average length of the fibers is 1 mm to 12 mm.

10. The composite panel of claim 1, wherein the composite panel comprises two cementitious coatings on opposite surfaces of the foam stock.

11. The composite panel of claim 1, wherein the composite panel is a Class A material in the ASTM E84 tunnel test.

12. The composite panel of claim 1, wherein a flame spread rating of the composite panel is equal to or less than 25.

13. The composite panel of claim 1, wherein a smoke development rating of the composite panel is equal to or less than 450.

14. A tile backer board, sound barrier, or roofing panel comprising the composite panel of claim 1.

15. A composite panel comprising: a foam stock comprising a recycled filler, wherein the recycled filler is present in an amount equal to or greater than 10% by weight, based on the total weight of the foam stock; wherein the foam stock has a density of 10 lb/ft.sup.3 to 25 lb/ft.sup.3; wherein a compressive strength of the foam stock is equal to or greater than 100 psi; and wherein a thickness of the composite panel is 1 inch to 4 inches.

16. The composite panel of claim 15, wherein the foam stock comprises polyurethane in an amount of 1% to 50% by weight, based on the total weight of the foam stock.

17. A method of making a polyurethane or polyisocyanurate foam, comprising: mixing one or more isocyanates selected from the group consisting of diisocyanates, polyisocyanates, and mixtures thereof, one or more polyols; and a filler to produce a mixture, wherein the filler is present in an amount from greater than 50% to 90% by weight, based on the total weight of the mixture; applying the mixture to a mold; allowing the mixture to react and expand to form the polyurethane or polyisocyanurate foam; and applying a cementitious coating on the polyurethane or polyisocyanurate foam; wherein the mixture applied to the mold has a tack free time of from 90 seconds to 7 minutes; wherein a compressive strength of the polyurethane or polyisocyanurate foam is equal to or greater than 100 psi; and wherein the polyurethane or polyisocyanurate foam has a density of 10 lb/ft.sup.3 or greater.

18. The method of claim 17, wherein the mixture applied to the mold has a cream time of from 20 seconds to 120 seconds.

19. The method of claim 17, wherein the mixture is applied to the mold at a viscosity of 20,000 cPs to 100,000 cPs at the temperature of the mixture.

Description

EXAMPLES

(1) The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices and/or methods claimed herein are made and evaluated, and are intended to be purely exemplary and are not intended to limit the scope of the disclosure. Unless indicated otherwise, parts and percentages are on a weight basis, temperature is in ° C. or is at ambient temperature, and pressure is at or near atmospheric.

(2) Mechanical Properties of Filled Polyurethane Foams.

(3) Preparation of polyurethane foams: Polyurethane foams were prepared using three different polyols labeled as Polyol A, a petroleum-derived polypropylene based polyol having a hydroxyl number of 240 mg KOH/g, a functionality of 3, and a viscosity of 250 mPa.Math.s; Polyol B, a glycerin initiated polyether polyol having a hydroxyl number of 240 mg KOH/g, a functionality of 3, and a viscosity of 250 mPa.Math.s at 25° C.; and Polyol C, a sucrose/amine initiated polyether polyol having a hydroxyl number of 350 mg KOH/g, a functionality of 5.5, and a viscosity of 2,500 mPa.Math.s at 25° C.

(4) The composites were prepared by wetting fly ash and ⅛″ chopped fiber glass in an extruder with concurrent streams of polyol (about 12% by weight of the foam) and methylene diphenyl diisocyanate (about 13% by weight of the foam) and optionally a catalyst and simultaneously stirring began. The mixture was extruded into a cardboard box and allowed to freely rise and cure. The physical properties of the composites, including flexural strength, density, handleability, extension, and modulus were determined. The handleability is a measure of the ability of the material to be flexed during use and is calculated as 0.5×breaking load×ultimate deflection/thickness of the test specimen. The extension is a measure of the deflection of a sample during the three point bend test as defined in ASTM C947-03. The modulus is calculated from the stress/strain curve of the three point bend test. Normalized flexural strength is the ratio of flexural strength divided by the density.

(5) TABLE-US-00002 TABLE 2 Components and mechanical properties of filled polyurethane foams: Foam #1 Foam #2 Foam #3 Polyol Polyol Polyol Polyol A B C Polyol conc. (wt %) 17% 19% 14% Isocyanate conc. (wt %) 13% 14% 13.4%   Surfactant Silicone-based Surfactant conc. (wt %) 0.16%   Fiber glass conc. (wt %)  1%  4%  5% Filler conc. (wt %) 69% 66% 68% Catalyst conc. (pphp) 0.2 0.1 Water conc. (wt %) 0.17%   0.31%   0.11%   Viscosity (cPs) 7590 35000 72300 (77° F.) (80° F.) (85° F.) Cream time (sec) 115 85 41 Tack-free time (sec) 240 140 375 Density (pcf) 21.7 17.0 22.6 Modulus (ksi) 31.6 15.0 26.5 Flexural strength (psi) 413 352 271 Extension (in.) 0.041 0.089 0.611 Handleability 4.02 7.69 7.43

(6) Summary: As shown in Table 2, the polyurethane foams prepared using Polyols A-C produced foams having suitable density, modulus, flexural strength, extension, and handleability. The cream time for the three samples was 41 seconds up to 115 seconds. The tack-free time was from 140 seconds up to 375 seconds.

(7) The compositions and methods of the appended claims are not limited in scope by the specific compositions and methods described herein, which are intended as illustrations of a few aspects of the claims and any compositions and methods that are functionally equivalent are intended to fall within the scope of the claims. Various modifications of the compositions and methods in addition to those shown and described herein are intended to fall within the scope of the appended claims. Further, while only certain representative materials and method steps disclosed herein are specifically described, other combinations of the materials and method steps also are intended to fall within the scope of the appended claims, even if not specifically recited. Thus, a combination of steps, elements, components, or constituents may be explicitly mentioned herein; however, other combinations of steps, elements, components, and constituents are included, even though not explicitly stated. The term “comprising” and variations thereof as used herein is used synonymously with the term “including” and variations thereof and are open, non-limiting terms. Although the terms “comprising” and “including” have been used herein to describe various embodiments, the terms “consisting essentially of” and “consisting of” can be used in place of “comprising” and “including” to provide for more specific embodiments and are also disclosed. As used in this disclosure and in the appended claims, the singular forms “a”, “an”, “the”, include plural referents unless the context clearly dictates otherwise.