WO2020263527A1

WO2020263527A1 - Mineral wool insulation

Info

Publication number: WO2020263527A1
Application number: PCT/US2020/036192
Authority: WO
Inventors: Aaron THALER; Matthew Gawryla
Original assignee: Owens Corning Intellectual Capital, Llc
Priority date: 2019-06-28
Filing date: 2020-06-04
Publication date: 2020-12-30

Abstract

Mineral wool insulation products having an increased thermal strength factor are provided.

Description

MINERAL WOOL INSULATION

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S. Provisional Application No. 62/867,985, filed June 28, 2019, the entire content of which is incorporated by reference herein.

FIELD

[0002] The general inventive concepts relate to mineral wool products and, more particularly, to mineral wool insulation having a balance of performance properties.

BACKGROUND

[0003] Mineral wool products are well known and have been used extensively in the building industry for insulation (both thermal and acoustic) and fire protection. The mineral wool products are commonly provided in the form of batts or boards.

[0004] A general process of making mineral wool products includes preparing a molten mineral melt, fiberizing the mineral melt via internal or external centrifugation to form a plurality of mineral wool fibers, attenuating the mineral wool fibers with a gas stream, and collecting the mineral wool fibers in the form of a web. A binder or sizing composition is typically applied to the mineral wool fibers when entrained in the gas stream, or onto the web. The web of fibers may be consolidated by crossdapping or other consolidation methods and cured, such as by passing the consolidated web of fibers through a curing oven. The cured web may be cut into products of desired sizes and dimensions.

[0005] Binders used to form the mineral wool products are generally aqueous solutions that include a thermosetting resin and additives such as crosslinking catalysts, adhesion- promoters, dedusting oils, and so forth. In some instances, the binder may include a water repelling agent, such as a silicone ( e.g ., a polysiloxane). Alternatively, a water repelling agent may be applied to the mineral wool fibers or web separately from the binder.

[0006] In the production of mineral wool insulation, there are many factors that compete against one another for particular performance goals. For example, increasing compressive strength generally results in a reduction in thermal conductivity; increasing density generally increases cost; etc. Thus, there is an unmet need for an improved mineral wool insulation that balances multiple competing properties.

SUMMARY

[0007] The general inventive concepts relate to mineral wool insulation having an improved collection of properties. To illustrate various aspects of the general inventive concepts, several exemplary embodiments of mineral wool insulation are disclosed.

[0008] In one exemplary embodiment, a mineral wool insulation comprises a plurality of mineral wool fibers; and a binder, wherein the mineral wool insulation has a thermal strength factor (TSF) greater than or equal to 90, as calculated by the equation:

wherein cs is a compressive strength of the mineral wool insulation in lbs/ft², wherein tc is a thermal conductivity of the mineral wool insulation at 75 °F in BTU· in/hr · ft² °F, wherein d is a density of the mineral wool insulation in lbs/ft³, and wherein / is a percent loss on ignition of the mineral wool insulation.

[0009] In some exemplary embodiments, the compressive strength of the mineral wool insulation is in the range of 432 lbs/ft² to 2,880 lbs/ft².

[0010] In some exemplary embodiments, the thermal conductivity of the mineral wool insulation is less than or equal to 0.25 BTU in/hr ft^{2 o}F.

[0011] In some exemplary embodiments, the density of the mineral wool insulation is in the range of 7 lbs/ft³ to 12 lbs/ft³. In some exemplary embodiments, the density of the mineral wool insulation is in the range of 7.5 lbs/ft³ to 11.5 lbs/ft³. In some exemplary embodiments, the density of the mineral wool insulation is in the range of 8 lbs/ft³ to 11 lbs/ft³.

[0012] In some exemplary embodiments, the percent loss on ignition of the mineral wool insulation is in the range of 2 to 8. In some exemplary embodiments, the percent loss on ignition of the mineral wool insulation is in the range of 3 to 7.

[0013] In one exemplary embodiment, a mineral wool insulation comprises a plurality of mineral wool fibers; and a binder, wherein the mineral wool insulation has a thermal strength factor (TSF) greater than or equal to 1.87, as calculated by the equation: TSF = tcxdxV

wherein cs is a compressive strength of the mineral wool insulation in kPa, wherein tc is a thermal conductivity of the mineral wool insulation at 75 °F in W/m K, wherein d is a density of the mineral wool insulation in kg/m³, and wherein / is a percent loss on ignition of the mineral wool insulation.

[0014] In some exemplary embodiments, the compressive strength of the mineral wool insulation is in the range of 20.68 kPa to 137.90 kPa.

[0015] In some exemplary embodiments, the thermal conductivity of the mineral wool insulation is less than or equal to 0.036 W/m K.

[0016] In some exemplary embodiments, the density of the mineral wool insulation is in the range of 112.13 kg/m³ to 192.22 kg/m³. In some exemplary embodiments, the density of the mineral wool insulation is in the range of 120.14 kg/m³ to 184.21 kg/m³. In some exemplary embodiments, the density of the mineral wool insulation is in the range of 128.15 kg/m³ to 176.20 kg/m³.

[0017] In some exemplary embodiments, the percent loss on ignition of the mineral wool insulation is in the range of 2 to 8. In some exemplary embodiments, the percent loss on ignition of the mineral wool insulation is in the range of 3 to 7.

[0018] In some exemplary embodiments, an average diameter of the mineral wool fibers is in the range of 2 pm to 9 pm.

[0019] In some exemplary embodiments, the binder is a thermoset resin.

[0020] In some exemplary embodiments, the mineral wool insulation is in the form of a board.

[0021] In some exemplary embodiments, the mineral wool insulation comprises at least one facing material on a surface of the board.

[0022] In one exemplary embodiment, a continuous insulation system is provided that uses any of the mineral wool insulation encompassed by the general inventive concepts, as described herein. [0023] In one exemplary embodiment, a curtain wall insulation system is provided that uses any of the mineral wool insulation encompassed by the general inventive concepts, as described herein.

[0024] In one exemplary embodiment, a pipe insulation is provided that uses any of the mineral wool insulation encompassed by the general inventive concepts, as described herein.

[0025] Other aspects and features of the general inventive concepts will become more readily apparent to those of ordinary skill in the art upon review of the following description of various exemplary embodiments in conjunction with the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The general inventive concepts, as well as embodiments and advantages thereof, are described below in greater detail, by way of example, with reference to the drawings in which:

[0027] Figure 1 is a graph showing thermal conductivity (BTU· in/hr· ft² °F) plotted against density (lbs/ft³) for mineral wool insulation.

[0028] Figure 2 is a graph showing compressive strength (lbs/ft²) plotted against density (lbs/ft³) for mineral wool insulation.

DETAILED DESCRIPTION

[0029] Several illustrative embodiments will be described in detail with the understanding that the present disclosure merely exemplifies the general inventive concepts. Embodiments encompassing the general inventive concepts may take various forms and the general inventive concepts are not intended to be limited to the specific embodiments described herein.

[0030] The general inventive concepts are based, at least in part, on the discovery that controlling various competing properties of a mineral wool insulation product can result in a product with a collection of performance properties not currently available in mineral wool insulation. In addition, it was surprisingly discovered that the collection of properties can be achieved across a range of different densities. [0031] The exemplary mineral wool insulation products described herein may be produced in accordance with conventional manufacturing processes known to those of ordinary skill in the art. In general, a process of making a mineral wool insulation product includes a step of preparing a molten mineral melt. The molten mineral melt may comprise a variety of materials including, but not limited to, slags, various rocks (including basalt), glass, and combinations thereof. These materials are melted in a furnace, such as a cupola, to produce the molten mineral melt.

[0032] Next, the molten mineral melt is fiberized using well-known internal or external centrifugation techniques to form a plurality of mineral wool fibers. The plurality of mineral wool fibers may then be attenuated, for example, by a gas stream. The attenuated mineral wool fibers are deposited or otherwise collected in the form of a web. A binder composition may be applied to the mineral wool fibers when entrained in the gas stream or may be applied onto the web. The web of fibers is consolidated by cross-lapping or another consolidation method and cured by passing the consolidated web of mineral wool fibers through a curing oven. The cured web of mineral wool fibers may be cut into products of desired sizes and dimensions.

[0033] In one exemplary embodiment, a mineral wool insulation is provided. The mineral wool insulation includes a plurality of mineral wool fibers and a binder that, upon curing, holds the mineral wool fibers together.

[0034] The mineral wool insulation is constructed to have a compressive strength (as) in lbs/ft², a thermal conductivity ( tc ) at 75 °F in B TU · in/hr · ft² °F, a density ( d) in lbs/ft³, and a percent loss on ignition (/), wherein these properties are controlled to provide a thermal strength factor (TSF) of greater than 90 for the mineral wool insulation, according to Equation 1. cs

TSF = tcxdxl (1)

[0035] This formula was developed, at least in part, based on an analysis of the graphs shown in FIGS. 1-2. As shown in FIG. 1, the thermal conductivity of the mineral wool insulation generally decreases between a density of approximately 2.5 lbs/ft³ and a density of approximately 6.0 lbs/ft³. Thereafter, the thermal conductivity of the mineral wool insulation increases between a density of approximately 6.0 lbs/ft³ to a density of approximately 12.0 lbs/ft³. As can be seen in FIG. 2, the compressive strength of the mineral wool insulation generally rises as the density of the mineral wool insulation increases.

[0036] It was observed that at relatively high densities, compressive strength gains outweigh thermal conductivity penalties. It was also observed that lowering density and thermal conductivity can result in an increased TSF value, notwithstanding a decrease in compressive strength.

[0037] In some exemplary embodiments, the compressive strength of the mineral wool insulation is in the range of 432 lbs/ft² to 2,880 lbs/ft². Here, the compressive strength is measured at 10% deformation using ASTM Cl 65 (Procedure A) with a crosshead speed of 0.5 in/min.

[0038] In some exemplary embodiments, the thermal conductivity of the mineral wool insulation is less than or equal to 0.25 BTU in/hr ft^{2 o}F.

[0039] The mineral wool insulation products contemplated by the general inventive concepts are single density products (i.e., having a relatively uniform density throughout the product).

[0040] In some exemplary embodiments, the density of the mineral wool insulation is in the range of 7 lbs/ft³ to 12 lbs/ft³. In some exemplary embodiments, the density of the mineral wool insulation is in the range of 7.5 lbs/ft³ to 11.5 lbs/ft³. In some exemplary embodiments, the density of the mineral wool insulation is in the range of 8 lbs/ft³ to 11 lbs/ft³.

[0041] In some exemplary embodiments, the loss on ignition (LOI) percentage of the mineral wool insulation is in the range of 2 to 8. In some exemplary embodiments, the LOI percentage of the mineral wool insulation is in the range of 3 to 7. Loss on ignition refers to the difference in mass (here, as a %) of the mineral wool insulation that results from the removal (by burning off) of volatile substances (i.e., organic material) therefrom.

[0042] Certain other properties of the mineral wool insulation may also (either directly or indirectly) contribute to its TSF value. For example, the size (i.e., diameter) of the mineral wool fibers are one such property. Typically, larger diameter fibers may support an increased compressive strength, but larger diameter fibers will generally result in reduced thermal performance of the mineral wool insulation. [0043] In some exemplary embodiments, an average diameter of the mineral wool fibers is in the range of 2 pm to 9 pm.

[0044] The mineral wool spinning process results in a combination of fibers and shot, the difference primarily being size and aspect ratio. Shot is generally spherical in shape, while fibers are generally elongated. The inclusion of shot typically increases density and thermal conductivity while decreasing other properties and is detrimental to achieving high TSF. In certain embodiments, the mineral wool fibers comprise 50% to 90% by weight of the total weight of the mineral wool insulation. In certain embodiments, the mineral wool fibers comprise 50% to 97% by weight of the total weight of the mineral wool insulation. In certain embodiments, the mineral wool fibers comprise 50% to 99% by weight of the total weight of the mineral wool insulation.

[0045] In certain embodiments, the mineral wool fibers comprise one or more of basalt, bauxite, dolomite, peridotite, diabase, gabbro, limestone, nepheline syenite, silica sand, granite, clay, feldspar, phosphate-smelter slag, copper slag, and blast furnace slag. In certain embodiments, the spun mineral wool comprises at least 90% by weight of the total weight of the mineral wool insulation. In certain embodiments, the spun mineral wool melt comprises 90% to 99% by weight of the total weight of the mineral wool insulation. In certain embodiments, the spun mineral wool melt comprises 90% to 97% by weight of the total weight of the mineral wool insulation. In certain embodiments, the spun mineral wool melt comprises 90% to 95% by weight of the total weight of the mineral wool insulation. In some exemplary embodiments, the spun mineral wool melt is primarily (e.g., > 60%) made from slag.

[0046] Formation of the mineral wool fibers can include other additives, as known in the art. For example, a dedusting oil may be applied to the plurality of mineral wool fibers in accordance with any conventional means known to those of skill in the art. In certain embodiments, the dedusting oil is applied to the mineral wool fibers by spraying. For example, in certain embodiments, the dedusting oil is sprayed onto the mineral wool fibers while the mineral wool fibers are entrained in the gas stream used to attenuate the mineral wool fibers. In certain other embodiments, the dedusting oil is sprayed onto the mineral wool fibers after the mineral wool fibers are collected as a web. Other exemplary additives include silicones and waxes (for hydrophobicity), surfactants (for hydrophilicity), infrared attenuating agents (for better thermal performance), fire retardants, etc. [0047] A variety of binder compositions may be used in the exemplary mineral wool insulation products disclosed herein. Typically, the binder composition includes a thermosetting resin. Exemplary binder compositions include, but are not limited to, carbohydrate-based binders, phenol-formaldehyde binders, urea-formaldehyde binders, melamine binders, and acrylic binders. In certain embodiments, the binder composition is a carbohydrate-based binder and is substantially free of formaldehyde. In certain embodiments, the binder composition is a phenol-formaldehyde binder.

[0048] In certain embodiments, the binder comprises 0.5% to 10% by weight of the total weight of the mineral wool insulation. In certain embodiments, the binder comprises 1% to 6% by weight of the total weight of the mineral wool insulation. In certain embodiments, the binder comprises 2% to 5% by weight of the total weight of the mineral wool insulation.

[0049] The mineral wool insulation products contemplated by the general inventive concepts are typically rigid members.

[0050] In some exemplary embodiments, the mineral wool insulation products are rigid boards that can be used in a host of applications, such as a sheathing material. Such rigid boards could also be used as part of a continuous insulation (Cl) system. Cl refers to insulation that is continuous across all structural members without thermal bridges other than fasteners and service openings. Cl can be installed on the interior, exterior, or be integral to any opaque surface of the building envelope. The Cl system can be used for insulating walls and/or roofs.

[0051] In some exemplary embodiments, the mineral wool insulation is shaped (e.g., on a mandrel) prior to curing, thereby forming a shaped rigid member. Such shaped rigid members can be used in a host of applications, such as pipe insulation (e.g., v-groove pipe insulation, precision cut pipe).

[0052] Other applications of the mineral wool insulation products will be appreciated by one of ordinary skill in the art. For example, the exemplary mineral wool insulation described herein may be used to provide thermal insulation, acoustic insulation, and/or fire protection to residential and commercial buildings. In certain embodiments, the mineral wool insulation is suitable for use as a safing insulation and has a melting point of at least 2,000 °F (1,093 °C). In certain embodiments, the mineral wool insulation is suitable for use as a curtain wall insulation in a perimeter fire containment system. [0053] In certain embodiments, the mineral wool insulation includes at least one facing material on a surface thereof. In certain embodiments, the at least one facing material comprises a foil scrim kraft facing. In certain embodiments, the at least one facing material comprises an all service jacket facing. In certain embodiments, the at least one facing material comprises a foil scrim polyethylene facing. In certain embodiments, the at least one facing material comprises a nonwoven glass fiber mat. In certain embodiments, the at least one facing material comprises a nonwoven polyester fiber mat. In certain embodiments, the at least one facing material comprises a polypropylene scrim kraft facing.

EXAMPLES

[0054] Four (4) examples of mineral wool insulation boards according to the general inventive concepts were produced (i.e., Samples 1-4) and analyzed, as shown in Table 1 below.

[0055] The compressive strength (c.s) of each sample was determined in lbs/ft². As noted above, the compressive strength was measured at 10% deformation using ASTM Cl 65 (Procedure A) with a crosshead speed of 0.5 in/min. The thermal conductivity ( tc ) at 75 °F of each sample was determined in BTU in/hr ft^{2 o}F. The density (< d) of each sample was determined in lbs/ft³. The percent loss on ignition (/) of each sample was determined. Using these measured values, a TSF value was calculated for each sample using Equation 1, as described above.

[0056] For comparison purposes, three (3) commercial mineral wool insulation boards (i.e., Samples 5-7) were purchased. The compressive strength (c.s) in lbs/ft², the thermal conductivity ( tc ) in BTU in/hr ft^{2 o}F, and the density (d) in lbs/ft³ were determined for each board based on information in the product datasheet. Since the production specification information did not include loss on ignition percentage values, the percent loss on ignition (/) was determined for each board by direct measurement.

[0057] All seven (7) samples comprise similar mineral wool fibers (e.g., diameters) and binders.

[0058] As shown in the Table 1, the inventive mineral wool insulation boards (i.e., Samples 1-4) each have a thermal strength factor (TSF) that exceeds that of the conventional mineral wool insulation boards (i.e., Samples 5-7). Table 1

# Values from product datasheet.

* Values measured on commercial product.

[0059] All percentages, parts, and ratios as used herein, are by weight of the total composition, unless otherwise specified. All such weights as they pertain to listed ingredients are based on the active level and, therefore, do not include solvents or by-products that may be included in commercially available materials, unless otherwise specified.

[0060] All references to singular characteristics or limitations of the present disclosure shall include the corresponding plural characteristic or limitation, and vice versa, unless otherwise specified or clearly implied to the contrary by the context in which the reference is made.

[0061] All combinations of method or process steps as used herein can be performed in any order, unless otherwise specified or clearly implied to the contrary by the context in which the referenced combination is made.

[0062] All ranges and parameters, including but not limited to percentages, parts, and ratios, disclosed herein are understood to encompass any and all sub-ranges assumed and subsumed therein, and every number between the endpoints. For example, a stated range of “1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more ( e.g ., 1 to 6.1), and ending with a maximum value of 10 or less e.g ., 2.3 to 9.4, 3 to 8, 4 to 7), and finally to each number 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 contained within the range.

[0063] The mineral wool insulation and corresponding manufacturing methods of the present disclosure can comprise, consist of, or consist essentially of the essential elements and limitations of the disclosure as described herein, as well as any additional or optional ingredients, components, or limitations described herein or otherwise useful in mineral wool insulation applications.

[0064] The mineral wool insulation of the present disclosure may also be substantially free of any optional or selected essential ingredient or feature described herein, provided that the remaining composition still contains all of the required ingredients or features as described herein. In this context, and unless otherwise specified, the term“substantially free” means that the selected composition contains less than a functional amount of the optional ingredient, typically less than 0.1% by weight, and also including zero percent by weight of such optional or selected essential ingredient.

[0065] To the extent that the terms“include,”“includes,” or“including” are used in the specification or the claims, they are intended to be inclusive in a manner similar to the term “comprising” as that term is interpreted when employed as a transitional word in a claim. Furthermore, to the extent that the term "or" is employed ( e.g ., A or B), it is intended to mean “A or B or both A and B.” When the Applicant intends to indicate“only A or B but not both,” then the term“only A or B but not both” will be employed. Thus, use of the term“or” herein is the inclusive, and not the exclusive use. In the present disclosure, the words“a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular.

[0066] In some embodiments, it may be possible to utilize the various inventive concepts in combination with one another. Additionally, any particular element recited as relating to a particularly disclosed embodiment should be interpreted as available for use with all disclosed embodiments, unless incorporation of the particular element would be contradictory to the express terms of the embodiment. Additional advantages and modifications will be readily apparent to those skilled in the art. Therefore, the disclosure, in its broader aspects, is not limited to the specific details presented therein, the representative apparatus, or the illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the general inventive concepts.

[0067] The scope of the general inventive concepts presented herein are not intended to be limited to the particular exemplary embodiments shown and described herein. From the disclosure given, those skilled in the art will not only understand the general inventive concepts and their attendant advantages, but will also find apparent various changes and modifications to the devices and systems disclosed. It is sought, therefore, to cover all such changes and modifications as fall within the spirit and scope of the general inventive concepts, as described and/or claimed herein, and any equivalents thereof.

Claims

WHAT IS CLAIMED IS:

1. A mineral wool insulation comprising:

a plurality of mineral wool fibers; and

a binder,

wherein the mineral wool insulation has a thermal strength factor (TSF) greater than 90, as calculated by the equation:

TSF =—— ,

tcxdxl

wherein cs is a compressive strength of the mineral wool insulation in lbs/ft², wherein tc is a thermal conductivity of the mineral wool insulation at 75 °F in BTU in/hr ft^{2 o}F,

wherein d is a density of the mineral wool insulation in lbs/ft³, and

wherein / is a percent loss on ignition of the mineral wool insulation.

2. The mineral wool insulation of claim 1, wherein the compressive strength of the mineral wool insulation is in the range of 432 lbs/ft² to 2,880 lbs/ft².

3. The mineral wool insulation of claim 1, wherein the thermal conductivity of the mineral wool insulation is less than or equal to 0.25 BTU· in/hr· ft² °F.

4. The mineral wool insulation of claim 1, wherein the density of the mineral wool insulation is in the range of 7 lbs/ft³ to 12 lbs/ft³.

5. The mineral wool insulation of claim 1, wherein the density of the mineral wool insulation is in the range of 8 lbs/ft³ to 11 lbs/ft³.

6. The mineral wool insulation of claim 1, wherein the percent loss on ignition of the mineral wool insulation is in the range of 2 to 8.

7. The mineral wool insulation of claim 1, wherein the percent loss on ignition of the mineral wool insulation is in the range of 3 to 7.

8. The mineral wool insulation of claim 1, wherein an average diameter of the mineral wool fibers is in the range of 2 pm to 9 gm.

9. The mineral wool insulation of claim 1, wherein the binder is a thermoset resin.

10. The mineral wool insulation of claim 1, wherein the mineral wool insulation is in the form of a board.

11. The mineral wool insulation of claim 9, wherein the mineral wool insulation comprises at least one facing material on a surface of the board.

12. A continuous insulation system comprising the mineral wool insulation of any one of claims 1 to 11.

13. A curtain wall insulation system comprising the mineral wool insulation of any one of claims 1 to 11.

14. A pipe insulation comprising the mineral wool insulation of any one of claims 1 to 11.