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 an inorganic ammonium salt, wherein the carbohydrate component comprises cellulose hydrolysate sugars comprising monosaccharides, including dextrose and xylose, disaccharides, and polysaccharides, wherein the cellulose hydrolysate sugars comprise 1-95 wt. % glucose and 0.5-15 wt. % xylose.

2. The curable binder composition of claim 1, wherein the curable binder composition is aqueous and comprises a solids content of 5-95 wt. %, based on the weight of the total aqueous binder composition.

3. The curable binder composition of claim 1, wherein further to dextrose and xylose the cellulose hydrolysate sugars comprise one or more saccharides as a remainder selected from the group consisting of fructose, mannose, galactose, and a polysaccharide fraction.

4. The curable binder composition of claim 3, wherein the polysaccharide fraction comprises arabinan, galactan and mannan of polymerization degrees ranging from 2-20.

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

6. The curable binder composition of claim 1, further comprising 0.1-1.0 wt. % of a silicon-containing coupling agent, based on the weight of the solids in the binder composition.

7. An assembly of matter comprising mineral fibers, synthetic fibers or natural fibers, cellulosic particle or sheet material, bonded together by the curable binder composition of claim 1 and/or reaction product(s) resulting from the condensation of the carbohydrate component and inorganic ammonium salt of the curable binder composition of claim 1, or by a binder produced by subjecting the curable binder composition of claim 1 to curing conditions.

8. The assembly of matter of to claim 7, comprising an insulation product comprising 70-99 wt. % mineral fibers based on glass wool or stone wool, and bonded together such that they become organized in a fiber mat to be processed into an insulation product.

9. The assembly of matter of claim 7, being a non-woven glass fiber veil for use in battery separators or as substrate for roofing membranes or shingles.

10. The assembly of matter of to claim 7, comprising one or more of sand particles, cellulosic fibers, wood shavings, wood layers, wood sheets, wood pulp, fiber boards, particle boards, oriented strand boards, plywood and additional materials commonly used in the manufacturing of composite wood boards, wherein the curable binder composition comprises about 5 to about 30 wt. % with respect to the total weight of the assembly of matter.

11. A process for producing the assembly of matter of claim 7, comprising (i) the provision of (a) a carbohydrate component comprising 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.

12. The process of claim 11, wherein the curing conditions are performed at a temperature ranging from 90-200° C.

Description

(1) The invention will be explained in more details in the examples below with reference to the attached Figures, in which:

(2) FIG. 1 shows tensile strength of invention sample 1 compared to standard glucose based binder compositions;

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

(4) FIG. 3 shows tensile strength data for invention sample 5 compared to glucose based binder compositions; and.

(5) FIG. 4 shows tensile strength data for invention sample 12 compared to standard glucose based binder compositions

EXAMPLE 1

(6) 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):

(7) 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

(8) For comparison purposes, a binder composition comprising dextrose and ammonium sulphate in the same ratio was prepared.

(9) 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.

(10) 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.

(11) 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.

(12) 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.

(13) 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.