IMPROVED BINDER COMPOSITIONS AND USES THEREOF

Abstract

The present invention relates to improved curable binder compositions comprising cellulose hydrolysate sugars and an inorganic ammonia salt, products making use thereof and a process for making such products. The invention binders show improved bond strength under dry and wet conditions.

Claims

1. A curable binder composition comprising a carbohydrate component and a salt of an inorganic acid with ammonia wherein the carbohydrate component consists at least partially in cellulose hydrolysate sugars comprising monosaccharides, including dextrose and xylose, disaccharides and polysaccharides.

2. The curable binder composition of claim 1 wherein the cellulose hydrolysate sugars make up 10 to 100 wt % of the sugar component.

3. The curable binder composition of claim 1 wherein said composition is aqueous and comprises a solid content of 5 to 95 w %, based on the weight of the total aqueous binder composition.

4. The curable binder composition of claim 1 wherein the carbohydrate component comprises 1 to 95 wt % glucose and 0.5 to 15 wt % xylose, the remainder being fructose, mannose, galactose and/or a polysaccharide fraction.

5. The curable binder composition of claim 1 wherein the carbohydrate component comprises 1 to 95 wt % glucose and 0.5 to 15 wt % xylose, the remainder being fructose, mannose, galactose and/or a polysaccharide fraction and the polysaccharide fraction comprises arabinan, galactan, and/or mannan.

6. The curable binder composition of claim 1 wherein the carbohydrate component comprises 1 to 95 wt % glucose and 0.5 to 15 wt % xylose, the remainder being fructose, mannose, galactose and/or a polysaccharide fraction and the polysaccharide content varies between 1 and 90 wt %.

7. The curable binder composition of claim 4 wherein the carbohydrate component comprises 1 to 95 wt % glucose and 0.5 to 15 wt % xylose, the remainder being fructose, mannose, galactose and/or a polysaccharide fraction and the polysaccharide fraction is a blend of polysaccharides of different polymerization degrees, varying from 2 to 20, with an average polymerization degree comprised between 3 and 7.

8. The curable binder composition of claim 1 further comprising coupling agents, dyes, antifungal agents, antibacterial agents, hydrophobes and/or other additives known in the art.

9. The curable binder composition of claim 1 comprising a silicon-containing coupling agent, in the range of from about 0.1 to about 1% by weight based on the weight of the solids in the binder composition.

10. An assembly of matter comprising mineral fibers, synthetic fibers or natural fibers, cellulosic particle or sheet material, bonded together by a curable binder composition of claim 1 and/or reaction product resulting from the condensation of the carbohydrate component and inorganic ammonia salt of said curable binder composition of claim 1, or by a binder obtained by subjecting to curing conditions an aqueous curable binder composition of claim 1.

11. An assembly of matter according to claim 10 being an insulation product, comprising mineral fibers in an amount ranging from 70 to 99% by weight, based on glass wool or stone wool, bonded together such that they become organized in a fiber mat to be processed into an insulation product.

12. An assembly of matter according to claim 10 being a non-woven glass fiber veil, for use in battery separators, or as substrate for roofing membranes or shingles.

13. An assembly of matter according to claim 10 being sand particles or cellulosic fibers, wood shavings, wood layers or sheets, wood pulp and other materials commonly used to manufacture composite wood boards, including fiber boards, particle boards, oriented strand boards or plywood, the binder content of which ranging from about 5 to 30% wt with respect to the total weight of the assembly.

14. A process for the preparation of an assembly of matter of claim 10 comprising (i) the provision of (a) a carbohydrate component consisting at least partially of cellulose hydrolysate sugars, (ii) the provision of appropriate amounts of (b) an inorganic ammonium salt, (iii) the successive or simultaneous application of (a) and (b), optionally as an aqueous composition comprising (a) and (b) and optionally (a) cross-linked by (b), onto particulate, fibrous or cellulosic particulate or sheet material to produce resinated material, and (iv) subjecting the resulting resinated material to curing conditions and allowing for evaporation of excess water.

15. The process of claim 14 wherein curing is effected at a temperature ranging from 90-200 C.

16. Method of use of cellulose hydrolysate sugars as sugar component in a curable binder composition comprising a carbohydrate component and a salt of an inorganic acid with ammonia, in order to improve dry and/or wet strength of an assembly of matter comprising mineral fibers, synthetic or natural fibers, cellulosic particles or sheet material, bonded together by said curable binder composition and/or reaction product resulting from the condensation and/or curing of the carbohydrate component and inorganic ammonia salt of said curable binder composition.

Description

[0036] The invention will be explained in more details in the examples below with reference to the attached Figures, in which:

[0037] FIG. 1 shows tensile strength of invention sample 1 compared to standard glucose based binder compositions;

[0038] FIG. 2 shows tensile strength data for invention samples 2, 3 and 4 compared to standard glucose based binder compositions;

[0039] FIG. 3 shows tensile strength data for invention sample 5 compared to glucose based binder compositions; and.

[0040] FIG. 4 shows tensile strength data for invention sample 12 compared to standard glucose based binder compositions

EXAMPLE 1

[0041] An invention binder composition comprising cellulose hydrolysate and ammonium sulphate in a ratio of 85 parts total sugars for 15 parts ammonium sulphate was prepared. The cellulose hydrolysate has been obtained by enzymatic digestion of cellulosic material contained in household waste and shows the following composition (in parts by weight):

TABLE-US-00001 % % % Sample Glucose Xylose Oligomers Total 1 8 0.8 0.5 9.3 2 5.6 0.8 0.5 6.9 3 9.2 1.7 0.9 11.8 4 10.1 2.3 1.8 14.2 5 36.2 6.3 4.3 46.8 12 4.4 0.2 0.2 4.8

[0042] For comparison purposes, a binder composition comprising dextrose and ammonium sulphate in the same ratio was prepared.

[0043] Commercial Urea formaldehyde impregnated (A4 size) glass fiber veils were placed into a muffle furnace oven for 30 minutes at 600 C. in order to burnout the PF binder, and were then allowed to cool for 30 minutes. The obtained veil samples were weighted.

[0044] Approx. 400 g binder solution (2% solids) samples were poured into dip trays, and the obtained veil samples carefully fully immersed into the relevant binder solutions. The impregnated veils were cured at 190 C. for indicated periods of time varying from 0 to 600 seconds. Binder content was then measured and tensile strength determined as follows.

[0045] The tensile strength of the relevant cured binder impregnated veils was determined by means of mechanical testing instrument (M350-10CT). For each test a cured binder impregnated A4 veil was cut into 8 equal strips. Each strip was tested separately using a 50 Kg load cell (DBBMTCL-50 kg) at an automated test speed of 10 mm/min controlled by winTest Analysis software. Glass veil tensile plates were attached to the testometric machine in order to ensure a 100 mm gap between plates. Samples were placed vertically in the grippers; and the force was tarred to zero. Various parameters such as maximum load at peak, stress at peak and modulus at peak were evaluated by the software, and data presented as an average of 8 samples with standard deviation. The average maximum load at peak or stress at peak defined as the tensile strength.

[0046] The figures show development of strength as cure evolves. As can be seen in the figures for relevant samples, the cellulose hydrolysate based binder compositions confer similar or improved strength as compared to glucose based binders comprising the same amount of total sugar.

[0047] It has further been found that the dry bond strength is significantly improved for invention binder compositions as compared to standard glucose based binder compositions, both compositions having the same amount of total sugar.