BINDING COMPOUND BASED ON FURAN RESIN, REDUCING SUGAR AND/OR NON-REDUCING SUGAR

Abstract

A binding compound for mineral or organic fibres, includes from 40 to 95 wt % of furan resin, and from 5 to 60 wt % of at least one reducing sugar and/or of at least one non-reducing sugar, relative to the total dry weight of the composition, the binding composition having a dry matter content between 0.5 to 50 wt %.

Claims

1. Aqueous binding compound for mineral or organic fibres comprising: from 40 to 95 wt % of furan resin, and from 5 to 60 wt % of at least one reducing sugar and/or of at least one non-reducing sugar, relative to the total dry weight of the composition, said binding composition having a dry matter content between 0.5 to 50 wt %.

2. The binding compound according to claim 1, wherein the furan resin is a furfuryl alcohol resin, called poly(furfuryl alcohol).

3. The binding compound according to claim 1, comprising from 10 to 50 wt % of at least one reducing sugar and/or of at least one non-reducing sugar relative to the total dry weight of the composition.

4. The binding compound according to claim 3, comprising from 20 to 30 wt % of at least one reducing sugar and/or of at least one non-reducing sugar relative to the total dry weight of the composition.

5. The binding compound according to claim 1, wherein the reducing sugar is glucose, galactose, mannose, fructose, lactose, maltose, isomaltose, cellobiose or a dextrin.

6. The binding composition according to claim 5, wherein the reducing sugar is glucose.

7. The binding compound according to claim 5, wherein the dextrin has a dextrose equivalent (DE) above 5.

8. The binding compound according to claim 7, wherein the dextrin has a dextrose equivalent (DE) above 50.

9. The binding compound according to claim 1, wherein the non-reducing sugar is trehalose, an isotrehalose, sucrose, an isosucrose, melezitose, gentianose, raffinose, erlose, umbelliferose, stachyose or verbascose.

10. The binding compound according to claim 9, wherein the non-reducing sugar is sucrose.

11. The binding compound according to claim 1, wherein the binding compound is free from hydrogenated sugars.

12. The binding compound according to claim 1, wherein the binding compound has a dry matter content between 2 and 30 wt %; the furan resin and the reducing sugar and/or non-reducing sugar together representing at least 50 wt % of the dry matter of the binding compound.

13. The binding compound according to claim 1, wherein the binding compound has a pH between 3.0 and 10.0.

14. The binding compound according to claim 1, further comprising the additives given hereunder in the following proportions calculated on the basis of 100 parts by weight of reducing sugar and/or of non-reducing sugar and of furan resin: 0 to 5 parts of silane, 0 to 25 parts of oil, 0 to 10 parts of a hydrophobic agent, and 0 to 30 parts of urea.

15. A method for making an insulation product based on mineral or organic fibres bound with an organic binder, comprising: (a) applying a binding compound according to claim 1 on mineral or organic fibres, (b) forming an assembly of mineral or organic fibres, (c) heating the assembly of mineral or organic fibres until said binding compound hardens.

16. The method according to claim 15, wherein said binding compound in step a) is applied on the mineral or organic fibres by spraying by means of spraying nozzles.

17. The method according to claim 15, wherein the assembly of mineral or organic fibres is a blanket of fibres, a board or a panel of fibres, a fibre-based moulded product, or a woven or non-woven textile.

18. The method according to claim 15, wherein step (c) comprises heating said assembly of fibres at a temperature between 100 C. and 250 C. for a time between 1 and 10 minutes.

19. The method according to claim 15, wherein the fibres are mineral fibres and the assembly of mineral fibres has, after the curing step (c), a loss on ignition (LOI) between 1 and 20 wt %.

20. An insulating product based on mineral or organic fibres bound with an organic binder, obtained by a method according to claim 15.

Description

EXAMPLES

Example 1

[0076] Aqueous binding compounds are prepared comprising, as furan resin, a furfuryl alcohol resin, called poly(furfuryl alcohol) (BioRez (TransFurans Chemicals, Belgium)) with glucose (D-(+)-Glucose 99.5% from Sigma Aldrich). The aqueous binding compounds presented below have a dry matter content of 20 wt %. The amount, i.e. the percentage by weight of poly(furfuryl alcohol) and of glucose, relative to the total dry weight of the composition, is varied in steps of 10%, as indicated in Table 1.

TABLE-US-00001 TABLE 1 Percentage of poly(furfuryl Percentage of Sample name alcohol) glucose PFA_G_1 100 0 PFA_G_2 90 10 PFA_G_3 80 20 PFA_G_4 70 30 PFA_G_5 60 40 PFA_G_6 50 50 PFA_G_7 40 60 PFA_G_8 30 70 PFA_G_9 20 80 PFA_G_10 10 90 PFA_G_11 0 100

[0077] Two series of glass cloths are impregnated, respectively, with these aqueous binding compounds, then the cloths are passed through a suction device to remove surplus solution. Then the impregnated glass cloths are hardened in an oven thermostatically controlled to 220 C. After baking for 90 seconds and 120 seconds, the tensile breaking strength of a sample is determined. For this, the cloths are cut into strips (300 mm50 mm) and their ends are inserted in the jaws of a tensile tester. The tensile tester used is an MTS, the load cell is of 2 kN and the jaws use pneumatic clamping.

[0078] Table 2 shows the maximum force reached in tension for two baking times (90 seconds and 120 seconds) at a temperature 220 C., of the glass fibre cloths impregnated with a binding compound according to Table 1.

TABLE-US-00002 TABLE 2 Maximum force in Sample name Baking time tension (N) PFA_G_1 90 s 96.7 PFA_G_1 120 s 92.9 PFA_G_2 90 s 98.3 PFA_G_2 120 s 92.7 PFA_G_3 90 s 92.8 PFA_G_3 120 s 93.4 PFA_G_4 90 s 91.8 PFA_G_4 120 s 89.0 PFA_G_5 90 s 83.6 PFA_G_5 120 s 85.8 PFA_G_6 90 s 76.6 PFA_G_6 120 s 82.5 PFA_G_7 90 s 75.8 PFA_G_7 120 s 72.0 PFA_G_8 90 s 66.6 PFA_G_8 120 s 62.3 PFA_G_9 90 s 48.2 PFA_G_9 120 s 54.6 PFA_G_10 90 s Too low to be measured PFA_G_10 120 s 26.8 PFA_G_11 90 s Too low to be measured PFA_G_11 120 s Too low to be measured

[0079] It can be seen that the samples prepared according to the invention (PFA_G_2 to PFA_G_7) comprising from 10 to 60 wt % of glucose have satisfactory tensile strengths compared to that of the reference sample, which comprises 100 wt % of poly(furfuryl alcohol). However, the tensile mechanical properties of the samples (PFA_G_8 to PFA_G_11) comprising from 70 to 100 wt % of glucose decrease and even become very low, since measurements cannot be carried out on the samples comprising 90% and 100% of glucose respectively (PFA_G_10 and PFA_G_11).

Example 2

[0080] Aqueous binding compounds are prepared comprising 60 wt % of poly(furfuryl alcohol) as furan resin ((BioRez (TransFurans Chemicals, Belgium)) and 40 wt % of various sugars, relative to the total dry weight of the composition: [0081] reducing sugars such as fructose (D-()-fructose from Sigma Aldrich) and maltodextrin ((DE 16.5-19.5) MaldexTereos Syral), [0082] non-reducing sugar such as sucrose (D(+)-sucrose from Sigma Aldrich) and [0083] hydrogenated sugar such as sorbitol (D-sorbitol from Sigma Aldrich).
The aqueous binding compounds shown below have a dry matter content of 20 wt %. The solutions are described in Table 3.

TABLE-US-00003 TABLE 3 Percentage of poly(furfuryl Percentage of Sample name Sugar used alcohol) sugar used PFA_S_1 fructose 60 40 PFA_S_2 maltodextrin 60 40 (DE 16.5-19.5) PFA_S_3 sucrose 60 40 PFA_S_4 sorbitol 60 40

[0084] Table 4 below shows the maximum force reached in tension (measured by the method described in example 1) for two baking times at a temperature of 220 C., of the glass fibre cloths impregnated (like those described in example 1) with a binding compound according to Table 3.

TABLE-US-00004 TABLE 4 Maximum force in Baking time tension (N) PFA_S_1 90 s 87.7 PFA_S_1 120 s 85.2 PFA_S_2 90 s 108.4 PFA_S_2 120 s 111.7 PFA_S_3 90 s 91.8 PFA_S_3 120 s 92.5 PFA_S_4 120 s 50.1 PFA_S_4 300 s 67.1

[0085] It can be seen that the samples prepared according to the invention with fructose, maltodextrin and sucrose have satisfactory tensile strengths. Conversely, the use of sorbitol causes a considerable decrease in the mechanical properties of the binding compound in tension, even with a longer baking time (300 seconds).

Example 3

[0086] Aqueous binding compounds are prepared comprising the constituents given in Table 5 expressed in parts by weight (in percentage by weight relative to the total dry weight of the composition).

TABLE-US-00005 TABLE 5 Percentage of: poly(furfuryl Reducing alcohol).sup.(1) Percentage of Sample name sugar used (furan resin) sugar used PFA_P_1 100 0 PFA_P_2 glucose.sup.(2) 80 20 PFA_P_3 glucose.sup.(2) 60 40 .sup.(1)BioRez (TransFurans Chemicals, Belgium) .sup.(2)Hydrated D-glucose

[0087] The binding compounds are prepared by putting the constituents in a vessel containing water, with vigorous stirring. The binding compounds hereunder have a dry matter content of 5 wt %.

[0088] The binding compounds are used for forming insulation products based on glass wool.

[0089] Glass wool is manufactured by the internal centrifugation technique, in which the molten glass composition is transformed into fibres by means of a tool called a centrifugation spinner, comprising a basket forming the chamber for receiving the molten composition and a peripheral band having a plurality of orifices: the spinner is rotated about its axis of symmetry arranged vertically, the composition is ejected through the orifices under the effect of centrifugal force and the material coming out of the orifices is drawn out into fibres with the assistance of a drawing-out gas stream. The fineness of the glass fibres, measured by their micronaire value in the conditions described in patent application FR 2 840071, is equal to 15.8 l/min. There is a correspondence between the micronaire value and the average diameter of the fibres.

[0090] Conventionally, a binding compound spraying ring is arranged underneath the fiberizing spinner so as to distribute the binding compound evenly on the glass wool that has just been formed.

[0091] The mineral wool bonded in this way is collected on a belt conveyor having a width of 2.40 m, equipped with internal suction chambers that retain the mineral wool in the form of a felt or a layer on the surface of the conveyor. The conveyor then circulates in an oven maintained at 240 C. where the constituents of the binding compound polymerize to form a binder. The insulating product obtained has a density equal to 17.5 kg/m.sup.3, a thickness of about 80 mm immediately after manufacture and a loss on ignition equal to 4.7%.

[0092] In this example, the tensile strength is measured, according to standard ASTM C 686-71T, on a sample punched out of the insulating product. The sample is in the shape of a torus 122 mm long, 46 mm wide, with a radius of curvature of the cut-out from the outer edge equal to 38 mm and a radius of curvature of the cut-out from the inner edge equal to 12.5 mm.

[0093] The sample is arranged between two cylindrical mandrels of a testing machine, one of which is movable and moves at a constant speed. The breaking force F of the sample is measured and the tensile strength TS is calculated, defined by the ratio of the breaking force F (in newton) to the mass of the sample (in newton/gram). The tensile strength is measured immediately after manufacture (initial tensile strength).

[0094] Recovery of thickness indicates the elasticity in compression of the end product. To measure it, a pressure of compression is applied for a given time, such that the thickness is reduced to 1/4.8 of its initial value. After releasing this pressure of compression, the thickness is measured again. The recovery of thickness is the ratio of the thickness measured after releasing the pressure of compression to the initial thickness.

[0095] The properties of the insulation products are given in the table.

TABLE-US-00006 TABLE 6 Tensile Recovery of Sample name strength (N/g) thickness (cm) PFA_P_1 4.09 107.95 PFA_P_2 4.36 108.55 PFA_P_3 3.53 110.31

[0096] It can be seen that the insulating products prepared according to the invention (PFA_P_2 and PFA_P_3) have tensile strength and recovery of thickness equivalent to those of the reference sample (PFA_P_1).

Example 4

[0097] The procedure described in example 3 if followed, but using dextrose as the reducing sugar. Tables 7 and 8 specify the fractions by weight of the binding to compounds used and the mechanical properties of the samples of mineral wool obtained.

TABLE-US-00007 TABLE 7 Percentage of: poly (furfuryl Reducing alcohol).sup.(1) Percentage of Sample name sugar used (furan resin) sugar used PFA_P_4 100 0 PFA_P_5 dextrose.sup.(2) 60 40 .sup.(1)BioRez (TransFurans Chemicals, Belgium) .sup.(2)dextrose monohydrate from Roquette

TABLE-US-00008 TABLE 8 Tensile Recovery of Sample name strength (N/g) thickness (cm) PFA_P_4 4.45 105.66 PFA_P_5 4.06 108.11

[0098] It can be seen that the insulating product prepared according to the invention (PFA_P_5) has tensile strength and recovery of thickness equivalent to that of the reference sample (PFA_P_4).