Mineral fiber product

Abstract

The invention is directed to a mineral fibre product, comprising mineral fibres in contact with a binder resulting from the curing of an aqueous binder composition free of phenol and formaldehyde.

Claims

1. A mineral fiber product, wherein the product comprises mineral fibers in contact with a binder resulting from a curing of an aqueous binder composition which is free of phenol and formaldehyde and comprises: a component (i) in the form of one or more lignosulfonate lignins having a carboxylic acid group content of from 0.03 mmol/g to 1.4 mmol/g and a content of phenolic OH groups of from 0.3 mmol/g to 2.5 mmol/g, both based on a dry weight of lignosulfonate lignins, a component (ii) in the form of one or more cross-linkers, with the proviso that the aqueous binder composition does not comprise a cross-linker selected from epoxy compounds having a molecular weight MW of 500 or less; carbonyl compounds selected from aldehydes, carbonyl compounds of the formula R[C(O)R.sub.1]x in which: R represents a saturated or unsaturated and linear, branched or cyclic hydrocarbon radical, a radical including one or more aromatic nuclei which consist of 5 or 6 carbon atoms, a radical including one or more aromatic heterocycles containing 4 or 5 carbon atoms and an oxygen, nitrogen or sulfur atom, it being possible for the R radical to contain other functional groups, R.sub.1 represents a hydrogen atom or a C.sub.1-C.sub.10 alkyl radical, and x varies from 1 to 10, and polyamines.

2. The mineral fiber product of claim 1, wherein component (i) has a carboxylic acid group content of from 0.05 mmol/g to 0.6 mmol/g, based on a dry weight of lignosulfonate lignins.

3. The mineral fiber product of claim 1, wherein component (i) is present in the form of one or more lignosulfonate lignins having an average carboxylic acid group content of less than 1.8 groups per macromolecule, considering a M.sub.n wt. average of component (i).

4. The mineral fiber product of claim 1, wherein component (i) has a content of aliphatic OH groups of from 1.0 mmol/g to 8.0 mmol/g, based on a dry weight of lignosulfonate lignins.

5. The mineral fiber product of claim 1, wherein component (i) comprises one or more of ammonium lignosulfonates, calcium lignosulfonates, or magnesium lignosulfonates.

6. The mineral fiber product of claim 1, wherein component (i) comprises ammonium lignosulfonates and calcium lignosulfonates, a molar ratio of NH.sub.4.sup.+ to Ca.sub.2.sup.+ ranging from 5:1 to 1:5.

7. The mineral fiber product of claim 1, wherein the aqueous binder composition comprises added sugar in an amount of up to less than 5 wt.-%, based on a weight of lignosulfonate and sugar.

8. The mineral fiber product of claim 1, wherein the aqueous binder composition comprises component (i) in a concentration of from 50 wt.-% to 98 wt.-%, based on a dry weight of components (i) and (ii).

9. The mineral fiber product of claim 1, wherein component (ii) is in the form of one or more cross-linkers selected from one or more of -hydroxyalkylamide-cross-linkers, multifunctional organic amines, epoxy compounds having a molecular weight of more than 500, and multifunctional carbodiimides.

10. The mineral fiber product of claim 1, wherein component (ii) comprises one or more cross-linkers selected from -hydroxyalkylamide cross-linkers.

11. The mineral fiber product of claim 1, wherein component (ii) is present in a concentration of from 2 wt.-% to 90 wt.-%, based on a dry weight of component (i).

12. The mineral fiber product of claim 1, wherein a component (iii) in the form of one or more coupling agents is further present.

13. The mineral fiber product of claim 1, wherein a component (iv) in the form of one or more components selected from bases is further present.

14. The mineral fiber product of claim 1, wherein urea is further present.

15. The mineral fiber product of claim 1, wherein a component (v) in the form of one or more reactive or nonreactive silicones is further present.

16. The mineral fiber product of claim 1, wherein the product does not contain an ammonia-oxidized lignin (AOL).

17. The mineral fiber product of claim 1, wherein the aqueous binder composition consists essentially of a component (i) in the form of lignosulfonate lignins having a carboxylic acid group content of from 0.03 mmol/g to 2.0 mmol/g and a content of phenolic OH groups of from 0.3 mmol/g to 2.5 mmol/g, based on the dry weight of the lignosulfonate lignins, a component (ii) in the form of one or more cross-linkers, a component (iii) in the form of one or more coupling agents, optionally, a component in the form of one or more compounds selected from bases, optionally, urea, optionally, a component in the form of one more more reactive or non-reactive silicones, optionally, a hydrocarbon oil, optionally, one or more surface active agents, and water.

18. The mineral fiber product of claim 1, wherein the aqueous binder composition does not comprise a plasticizer.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) In the drawing,

(2) FIG. 1 shows the chemical structure of a lignosulfonate lignin for use as component (i) of a binder composition used according to the invention.

EXAMPLES

(3) In the following examples, several binders which fall under the definition of the present invention were prepared and compared to binders according to the prior art.

(4) The following properties were determined for the binders according to the present invention and the binders according to the prior art, respectively:

(5) Binder Component Solids Content

(6) The content of each of the components in a given binder solution before curing is based on the anhydrous mass of the components.

(7) Lignosulfonates were supplied by Borregaard, Norway and LignoTech, Florida as liquids with approximately 50% solid content. Primid XL552 was supplied by EMS-CHEMIE AG, Silane (Momentive VS-142 40% activity), was supplied by Momentive and was calculated as 100% for simplicity. NH.sub.4OH 24.7% was supplied by Univar and used in supplied form. PEG 200, urea, KOH pellets, 1,1,1 tris(hydroxyl-methyl)propane were supplied by Sigma-Aldrich and were assumed anhydrous for simplicity.

(8) Binder Solids

(9) The content of binder after curing is termed binder solids.

(10) Disc-shaped stone wool samples (diameter: 5 cm; height 1 cm) were cut out of stone wool and heat-treated at 580 C. for at least 30 minutes to remove all organics. The solids of the binder mixture was measured by distributing a sample of the binder mixture (approx. 2 g) onto a heat treated stone wool disc in a tin foil container. The weight of the tin foil container containing the stone wool disc was weighed before and directly after addition of the binder mixture. Two such binder mixture loaded stone wool discs in tin foil containers were produced and they were then heated at 200 C. for 1 hour. After cooling and storing at room temperature for 10 minutes, the samples were weighed and the binder solids was calculated as an average of the two results.

(11) A binder with a desired binder solids could then be produced by diluting with the required amount of water and 10% aq. silane (Momentive VS-142).

(12) Mechanical Strength Studies

(13) Bar Tests

(14) The mechanical strength of the binders was tested in a bar test. For each binder, 16 bars were manufactured from a mixture of the binder and stone wool shots from the stone wool spinning production.

(15) A sample of this binder solution having 15% dry solid matter (16.0 g) was mixed well with shots (80.0 g). The resulting mixture was then filled into four slots in a heat resistant silicone form for making small bars (45 slots per form; slot top dimension: length=5.6 cm, width=2.5 cm; slot bottom dimension: length=5.3 cm, width=2.2 cm; slot height=1.1 cm). The mixtures placed in the slots were then pressed with a suitably sized flat metal bar to generate even bar surfaces. 16 bars from each binder were made in this fashion. The resulting bars were then cured typically at 225 C. The curing time was 1 h. After cooling to room temperature, the bars were carefully taken out of the containers. Five of the bars were aged in a water bath at 80 C. for 3 h. This method of curing the prepared bars was used for the examples in Table 1.

(16) After drying for 3 days, the aged bars as well as five unaged bars were broken in a 3 point bending test (test speed: 10.0 mm/min; rupture level: 50%; nominal strength: 30 N/mm 2; support distance: 40 mm; max deflection 20 mm; nominal e-module 10000 N/mm 2) on a Bent Tram machine to investigate their mechanical strengths. The bars were placed with the top face up (i.e. the face with the dimensions length=5.6 cm, width=2.5 cm) in the machine.

(17) Binder Example, Reference Binder (Phenol-Formaldehyde Resin Modified with Urea, a PUF-Resol)

(18) This binder is a phenol-formaldehyde resin modified with urea, a PUF-resol.

(19) A phenol-formaldehyde resin is prepared by reacting 37% aq. formaldehyde (606 g) and phenol (189 g) in the presence of 46% aq. potassium hydroxide (25.5 g) at a reaction temperature of 84 C. preceded by a heating rate of approximately 1 C. per minute. The reaction is continued at 84 C. until the acid tolerance of the resin is 4 and most of the phenol is converted. Urea (241 g) is then added and the mixture is cooled.

(20) The acid tolerance (AT) expresses the number of times a given volume of a binder can be diluted with acid without the mixture becoming cloudy (the binder precipitates). Sulfuric acid is used to determine the stop criterion in a binder production and an acid tolerance lower than 4 indicates the end of the binder reaction.

(21) To measure the AT, a titrant is produced from diluting 2.5 ml conc. sulfuric acid (>99%) with 1 L ion exchanged water. 5 mL of the binder to be investigated is then titrated at room temperature with this titrant while keeping the binder in motion by manually shaking it; if preferred, use a magnetic stirrer and a magnetic stick. Titration is continued until a slight cloud appears in the binder, which does not disappear when the binder is shaken.

(22) The acid tolerance (AT) is calculated by dividing the amount of acid used for the titration (mL) with the amount of sample (mL):
AT=(Used titration volume (mL))/(Sample volume (mL))

(23) Using the urea-modified phenol-formaldehyde resin obtained, a binder is made by addition of 25% aq. ammonia (90 mL) and ammonium sulfate (13.2 g) followed by water (1.30 kg).

(24) The binder solids were then measured as described above and the mixture was diluted with the required amount of water and silane for mechanical measurements (15% binder solids solution, 0.5% silane of binder solids).

Examples 1-7

(25) In the following, the entry numbers of the binder example correspond to the entry numbers used in Table 1.

(26) The carboxylic acid group content of all lignosulfonates used for the binders according to the present invention was measured using 31P NMR and was found to be in the range of 0.05 to 0.6 mmol/g, based on the dry weight of the lignosulfonate lignins, while it was found for this specific batch used for examples 1, 2, 3, 4, 5, 6, 7 to be 0.14 mmol/g.

Example 1

(27) To 30.0 g lignosulfonate solution (50% solids), 0.4 g NH.sub.4OH (24.7%) was added and mixed followed by addition of 0.7 g Silane (Momentive VS-142 40% activity, 10% in water) and 68.9 g water were added and mixed to yield 15% solids and then used for test of mechanical properties in bar tests.

Example 3

(28) To 30.0 g lignosulfonate solution (50% solids), 0.4 g NH.sub.4OH (24.7%) was added and mixed followed by addition of 6.0 g Primid XL552 (100% solids) and mixing. Finally, 1.0 g Silane (Momentive VS-142 40% activity, 10% in water) and 102.6 g water were added and mixed to yield 15% solids and then used for test of mechanical properties in bar tests.

(29) Mechanical properties are presented in Table 1. For simplicity, quantities of all other components are recalculated based on 100 g of dry lignin.

(30) As can be seen from Table 1, in a combination of lignosulfonate and crosslinker (Primid XL 552) higher amounts of crosslinker lead to better mechanical properties.

(31) TABLE-US-00003 TABLE 1 PUF Binder composition ref 1 2 3 4 ammonium lignosulfonate (g solids) 100 100 100 100 urea (g) ammonia, 24.7% (g) 2.5 2.5 2.5 2.5 Primid XL552 (g) 0 25 40 60 Momentive VS 142 (% of binder 0.5 0.5 0.5 0.5 solids), based on 40% activity Binder properties Mechanical strength, unaged (N), 350 60 280 460 640 bar tests Mechanical strength, aged (N), 150 0 160 180 230 bar tests Curing temp, C. 200 225 225 225 225

Examples 5-7: Test of stone wool products

(32) The low density products have been examined for properties according to the product standard for Factory made mineral wool (MW) products, DS/EN13162:2012+A1:2015, meaning relevant mechanical properties besides other basic characteristics for stone wool products.

(33) The testing has been performed on slabs, where test specimens according to the dimensional specifications and to the number of test specimens required to get one test result, as stated in EN13162 for each of the different test methods, has been cut out. Each of the stated values for the mechanical properties obtained is an average of more results according to EN13162.

(34) Tests are performed on products or test specimens sampled directly from the production line before packing (line cuts) and/or for products or test specimens sampled from packs 24 hours after packing (24 h packs).

(35) Dimensions

(36) Dimensions of products and test specimens has been performed according to the relevant test methods, DS/EN822:2013: Thermal insulating products for building applicationsDetermination of length and width, and DS/EN823:2013: Thermal insulating products for building applicationsDetermination of thickness.

(37) Binder Content (Loss on Ignition)

(38) Determination of binder content is performed according to DS/EN13820:2003: Thermal insulating materials for building applicationsDetermination of organic content, where the binder content is defined as the quantity of organic material burnt away at a given temperature, stated in the standard to be (50020 C.). In the testing the temperature (59020 C., for at least 10 min or more until constant mass) has been used in order to make sure that all organic material is burnt away. Determination of ignition loss consists of at least 10 g wool corresponding to 8-20 cut-outs (minimum 8 cut-outs) performed evenly distributed over the test specimen using a cork borer ensuring to comprise an entire product thickness. The binder content is taken as the LOI. The binder includes oil and other binder additives.

(39) Tensile Strength

(40) The tensile strength of low density products has been determined according to EN 1608:2013: Thermal insulating products for building applicationsDetermination of tensile strength parallel to faces. The tensile strength is measured on test specimens from line cuts and on test specimens from 24 h packs.

(41) Self Deflection (f70)

(42) Self-deflection is measured according to an internal test method for determining the deflection caused by the net weight of a product. A test-specimen of length: 99010 mm and width: min. 2705 mm and max 6805 mm is placed horizontally on two supports (tilting table) with a mutual centre distance of (7002) mm and two moveable supporting devices. The self-deflection is measured in the middle of the specimen and recorded either mechanically or electrically (transducer with display) and read either on a scale or a digital display. If the original product is longer than 99010 mm the extra length is cut off. The self-deflection is measured on both surfaces of the test specimen. The accuracy of measurement is 0.2 mm for self-deflection <10 mm and 1 mm for self-deflection >10 mm).

(43) The self-deflection is reported as (f70, 70 cm span)=(f1+f2)/2 mm, where f1 is the measurement with surface 1 facing up and f2 is the measurement with surface 2 facing up.

(44) Testing is performed on test specimens from line cuts and on test specimens from 24 h packs.

Example 5

(45) The stone wool product has been produced by use of binder in example 5, at a curing oven temperature set to 275 C.

(46) 730.0 kg of ammonium lignosulfonate was placed in a mixing vessel to which 8.5 l NH.sub.4OH (24.7%) was added and stirred. Afterwards, 151 kg Primid XL552 solution (pre-made 31 wt % solution in water) and 43 kg PEG 200 (100% solids) were added and mixed followed by addition of 13 kg Silane (Momentive VS-142 40% activity, 10% in water) and 100 kg silicone (Wacker BS 1052, 12% in water).

(47) The binder from this example is used to produce a low density stone wool product, thickness and density were measured as indicated in Table 2. Curing oven temperature was set to 275 C.

Example 6

(48) The stone wool product has been produced by use of binder in example 6, at a curing oven temperature set to 275 C.

(49) 730.0 kg of ammonium lignosulfonate was placed in a mixing vessel to which 8.5 l NH 4 OH (24.7%) was added and stirred. Afterwards, 151 kg Primid XL552 solution (pre-made 31 wt % solution in water) and 43 kg PEG 200 (100% solids) were added and mixed followed by addition of 13 kg Silane (Momentive VS-142 40% activity, 10% in water) and 100 kg silicone (Wacker BS 1052, 12% in water).

(50) The binder from this example is used to produce a low density stone wool product, thickness and density were measured as indicated in Table 2. Curing oven temperature was set to 275 C.

Example 7

(51) The stone wool product has been produced by use of binder in example 53, at a curing oven temperature set to 275 C.

(52) 609.0 kg of ammonium lignosulfonate was placed in a mixing vessel to which 8 l NH 4 OH (24.7%) was added and stirred. Afterwards, 384 kg Primid XL552 solution (pre-made 31 wt % solution in water) was added and mixed followed by addition of 14 kg Silane (Momentive VS-142 40% activity, 10% in water).

(53) The binder from this example is used to produce a low density stone wool product, thickness and density were measured as indicated in Table 2. Curing oven temperature was set to 275 C.

(54) TABLE-US-00004 TABLE 2 Tensile strength, crosswise - packs Tensile strength, Self crosswise - line cuts Ignition deflection Sample Sigma Ignition Sample Sigma Thickness loss f(70) density (t) loss Thickness density (t) Example mm % mm kg/m3 kPa % mm kg/m3 kPa PUF- 145 2.82 7.2 32.3 7.6 2.50 153 31.0 10.2 reference 5 137 3.10 15.8 34.3 5.9 2.61 157 29.4 10.2 6 137 3.92 9.6 32.9 5.6 3.57 157 32.2 9.3 7 139 2.81 8.9 34.3 6.7 2.54 158 30.7 8.7