BINDER COMPOSITIONS AND USES THEREOF

Abstract

A binder used for manufacturing a composite product is prepared by combining i) Maillard reactants selected from: reducing sugar reactant(s) and nitrogen-containing reactant(s); curable reaction product(s) of reducing sugar reactant(s) and nitrogen-containing reactant(s); and combinations thereof; and ii) a resin; reactants of a resin; and combinations thereof.

Claims

1. A method of manufacturing a composite product comprising: applying a binder composition in the form of an aqueous solution to non or loosely assembled matter to provide resinated matter, wherein the binder composition consists of a binder composition prepared by combining i) Maillard reactants selected from: reducing sugar reactant(s) and nitrogen-containing reactant(s); curable reaction product(s) of reducing sugar reactant(s) and nitrogen-containing reactant(s); and combinations thereof; and ii) a resin; reactants of a resin; and combinations thereof; arranging the resinated matter to provide loosely arranged resinated matter; and subjecting the loosely arranged resinated matter to heat and/or pressure to cure the binder composition and to form the composite product.

2. A method in accordance with claim 1, wherein the resin is selected from latex resin; formaldehyde resin; formaldehyde resin selected from melamine formaldehyde resin, melamine urea formaldehyde resin, urea formaldehyde resin, phenol formaldehyde resin, melamine phenol formaldehyde resin, ketone formaldehyde resin; carboxymethyl-cellulose-based resin; starch-based resin; polyurethane resin; polyurea and polyurethane hybrid resin; rubber resin; Bakelite; Diallyl-phthalate resin; epoxy resin; epoxy novolac resin; benzoxazine resin used alone or hybridised with epoxy and/or phenolic resin; polyimide resin; bismaleimide resin; cyanate ester resin; polycyanurate resin; furan resin; silicone resin; thiolyte resin; vinyl ester resin; and combinations thereof.

3. A method in accordance with claim 1, wherein the resin is selected from latex resin and starch-based resin.

4. A method in accordance with claim 1, wherein the binder composition comprises at least 50 wt % dry weight of ii) the composition selected from a resin; reactants of a resin; and combinations thereof.

5. A method in accordance with claim 1, wherein Maillard reactants are prepared by combining reducing sugar reactant(s) which make up at least 15% by dry weight of the reactants of the binder composition and the nitrogen-containing reactant(s) which make up at least 2% by dry weight of the reactants of the binder composition.

6. A method in accordance with claim 1, wherein the nitrogen-containing reactant(s) is (are) selected from: inorganic amines, organic amines, organic amines comprising at least one primary amine, salts of an organic amine comprising at least one primary amine, polyamines, polyprimary polyamines and combinations thereof, any of which may be substituted or unsubstituted, ammonia, an inorganic or organic ammonium salt, an ammonium sulfate, an ammonium phosphate, and an ammonium citrate.

7. A method in accordance with claim 1, wherein the wherein the nitrogen-containing reactant(s) is selected from; diamines, di-primary diamines, HMDA, triamines, triprimary triamines, TPTA triprimary triamine(s), 4-(aminomethyl)-1,8-octanediamine and combinations thereof.

8. A method in accordance with claim 1, wherein the preparation of the binder composition prior to the application of the binder composition comprises reacting the reducing sugar reactant(s) and the nitrogen-containing reactant(s) to provide curable reaction product(s) of the reducing sugar reactant(s) and the nitrogen-containing reactant(s).

9. A method in accordance with claim 1, wherein the preparation of the binder composition prior to the application of the binder composition comprises stabilising the Maillard reactants.

10. A method in accordance with claim 9, wherein stabilising the Maillard reactants comprises reacting the Maillard reactant(s) with carbon dioxide (CO.sub.2).

11. A method in accordance with claim 10, wherein stabilising the Maillard reactants comprises treating curable reaction product(s) of the reducing sugar reactant(s) and the nitrogen-containing reactant(s) with carbon dioxide (CO.sub.2).

12. A method in accordance with claim 1, in which the binder composition is prepared by: a) reacting the reducing sugar reactant(s) and nitrogen-containing reactant(s) to provide curable reaction product(s) of the reducing sugar reactant(s) and the nitrogen-containing reactant(s); b) subsequently passing carbon dioxide through a solution comprising the curable reaction product(s) of the reducing sugar reactant(s) and the nitrogen-containing reactant(s); and c) subsequently combing the solution with ii) a resin; reactants of a resin; and combinations thereof.

13. A method in accordance with claim 1, wherein the composite product is a corrugated cardboard article and the binder composition is used to bond corrugations of fluted corrugated sheets to a planar linerboard.

Description

[0061] The invention will now be described by way of example only with reference to the accompanying drawing of which:

[0062] FIG. 1 shows 4-(aminomethyl)-1,8-octanediamine;

[0063] FIG. 2 shows an example of TPTA triprimary triamine (“AMOD”);

[0064] FIG. 3 shows results of a thermal stability study for binder compositions; and

[0065] FIG. 4 shows results of a temporal viscosity study.

[0066] FIG. 2 illustrates a TPTA triprimary triamine having three primary amines A, B, D with spacer groups which consist of carbon chains between each of its three primary amines. Each carbon atom is numbered to facilitate the explanation below.

The spacer group between primary amines A and B: [0067] has a spacer length of 7, i.e. carbon atoms 1, 2, 3, 4, 5, 6, 7 which together form the shortest chain of covalently bonded polyvalent atoms between primary amines A and B (the carbon atoms of the two branched chains 8, 9 and 10, 11 do not form part of the spacer length; [0068] has 11 polyvalent atoms, ie carbon atoms 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 (the carbon atoms 12, 13, 14, 15, 16 do not form part of the spacer group between A and B as they form a chain which connects the third primary amine D to the molecule).
The spacer group between primary amines A and D: [0069] has a spacer length of 10, i.e. carbon atoms 1, 2, 3, 4, 5, 12, 13, 14, 15, 16; [0070] has 14 polyvalent atoms, i.e. carbon atoms 1, 2, 3, 4, 5, 8, 9, 10, 11, 12, 13, 14, 15, 16.
The spacer group between primary amines B and D: [0071] has a spacer length of 8, i.e. carbon atoms 7, 6, 5, 12, 13, 14, 15, 16; [0072] has 10 polyvalent atoms, ie carbon atoms 7, 6, 5, 12, 13, 14, 15, 16, 10, 11 (the chain of carbon atoms 4, 3, 2, 1, 8, 9 does not form part of the spacer group between B and D as this form a chain which connects the other primary amine A to the molecule.
The total number of polyvalent atoms in the molecule is 19, i.e. carbon atoms 1 to 16 and the 3 nitrogen atoms of the 3 primary amines A, B and D.

EXAMPLE 1: BINDER COMPOSITION STABILITY TESTING

[0073] An aqueous binder composition (“H3823”—a 38 wt. % binder solids solution obtained by combining, by dry weight, 23 wt. % hexamethylenediamine (HMDA) as the nitrogen containing reactant and HFCS (high fructose corn syrup) as the reducing sugar reactant) was produced and observed to have an initial viscosity of about 15 centiPoise (cP). The initial sample was then divided into two (2) H3823 aliquots, which are exemplified as “Unshaken” (Series 2) and “Shaken” (Series 1) in FIG. 3. Both samples were subjected to approximately ambient temperature and pressure conditions, i.e. a temperature of about 68-70° F. and a pressure of approximately 1 atmosphere (atm). The first sample (“Shaken”) was sealed in a first storage vessel and unshaken, during which the temperature of the composition increased by about 7° F. (to a temperature of about 77° F.) over room temperature and remained at this elevated temperature for about five (5) days (about 120 hours). Following a period of about seven (7) days (about 168 hours), the first sample cooled to about 3° F. above room temperature.

[0074] The second sample (“Shaken”) was shaken three times a day, at a frequency of one shake approximately every 2-3 hours, on weekdays (Monday-Friday, unshaken on Saturday-Sunday). The temperature of the “Shaken” sample was observed to increase by about 10° F. over room temperature (to a temperature of about 80° F.) and remained at the elevated temperature for about seven (7) days (about 168 hours) and was observed to cool down to room temperature (about 70° F.) at a significantly slower rate. However, both the “Unshaken” and “Shaken” were found to comprise very similar viscosity values (about 18.5 cP) following the seven (7) day trial period. Additionally, both samples (“Shaken” and “Unshaken”) were observed to resist thermal damage when maintained at solution temperatures at or below 80° F.

EXAMPLE 2. ADDITIONAL THERMAL STABILITY MEASUREMENTS FOR BINDER COMPOSITIONS

[0075] In a trial separate from that described for the H3823 composition in Example 1, it was observed that a quart of the unmodified tanker batch gelled following overnight storage (a time period of about 10-12 hours) at a temperature of about 102° F. In an effort to extend usability and shelf life for the claimed composition, a separate sample was taken and time-dependent viscosity values were measured at ambient temperature and pressure conditions (about 20-25° F. and about 1 atm) over about 25 days (about 600 hours):

TABLE-US-00001 TABLE 1 Age of Sample (Days) Viscosity (cP) 1 13 3 14 7 17 13 18.5 18 24 21 34 22 55 23 120 25 Gel

[0076] Under ambient conditions, the sample exhibited a commercially viable product shelf life of greater than 3 weeks, with disadvantageous product gelling occurring around 3.5-4 weeks (about 600 to about 684 hours). In a follow-up trial, an additional time dependent assay was performed on an H3823 sample initially maintained under ambient conditions. As shown in Table 2, separate aliquots of the sample were then exposed to 1) a temperature of 98° F. after two days (about 48 hours) for a time period of about 48 hours; and 2) a temperature of 87° F. after four days (about 96 hours) for a time period of about 24 hours:

TABLE-US-00002 TABLE 2 Sample History Exposure Time Viscosity (cP) Maintained at room temperature 24 hours 17 cP for five days (~120 hours) Exposed to 98° F. after two days 48 hours Gel (~48 hours) Exposed to 87° F. after four days 24 hours 16 cP (~96 hours)

[0077] In an effort to achieve enhanced thermal/temporal stability, a 50 wt. % binder solids binder composition was prepared by mixing, by dry weight, 23 wt. % hexamethylenediamine (HMDA) and 77 wt. % high fructose corn syrup (described herein as “H5023”) and evaluated for shelf life stability as a function of compositional pH. A single aliquot, comprising a pH of about 11.3, was not treated with carbon dioxide (CO.sub.2), while five aliquots were subjected to bubbling with sufficient volumes of CO.sub.2 to achieve the pH levels disclosed in Table 3 below:

TABLE-US-00003 TABLE 3 Sample pH Observed Physical States/Measured Viscosity 11.3 (no CO.sub.2 treatment) Liquid (Day 18); Gel (Day 19) 9.4 (CO.sub.2 treatment) Liquid (Day 19); 190 cP (Day 110) 8.6 (CO.sub.2 treatment) Liquid (Day 19); 60 cP (Day 110) 8.3 (CO.sub.2 treatment) Liquid (Day 19); 52 cP (Day 110) 8.1 (CO.sub.2 treatment) Liquid (Day 19); 50 cP (Day 110) 8.0 (CO.sub.2 treatment) 31 cP (19 Days); 50 cP (Day 110)

[0078] As shown in Table 3, the H5023 sample (comprising 50% binder solids) exhibited a shelf life stability of at least about 110 days, after which no further measurements were recorded. It was observed that the CO.sub.2 treated samples (pH of 9.4, 8.6, 8.3, 8.1, and 8.0) exhibited sufficient thermal stability and characteristics associated with sufficient storage/shelf life stability, as well as stability during the transportation and/or processing of the material. For instance, the pH 8.0, CO.sub.2 treated aliquot had an initial viscosity of about 25 cP, a viscosity of about 31 cP after 19 days, and a viscosity of about 50 cP after 110 days.

[0079] A duplicate H5023 sample was then created and divided into three (3) separate aliquots for determining compositional viscosity following (1) no treatment with CO.sub.2; (2) CO.sub.2 treatment to produce a compositional pH of 9.33; and (3) CO.sub.2 treatment to produce a compositional pH of 8.22. The resulting viscosity values as a function of time and pH are provided in Table 4:

TABLE-US-00004 TABLE 4 Time Elapsed No CO.sub.2 CO.sub.2 Treatment CO.sub.2 Treatment (hours) Treatment pH = 9.33 pH = 8.22 24 22 23 25 120 42 28 30

[0080] Additional H5023 samples were treated with CO.sub.2 to produce the compositional pH values described in Table 5 (below), where commercial viability/stability was observed to be at or greater than about 90 days at pH values of 8.6 and 8.2:

TABLE-US-00005 TABLE 5 Viscosity Estimated Usability pH Days (cP) of Material (days) 11.2 19 Gel 15 9.3 64 138 60+ 8.6 80 50 90+ 8.2 64 36 90+

EXAMPLE 3. BINDER COMPOSITIONS COMPRISING INCREASED SOLIDS/NITROGEN-CONTAINING REACTANT CONCENTRATIONS

[0081] In further efforts to enhance commercial properties two (2) quarts of a 70 wt. % binder solids binder composition were prepared by combining, by dry weight, 30 wt. % hexamethylenediamine (HMDA) and 70 wt. % high fructose corn syrup (described herein as “H7030”). The results for various (CO.sub.2 treated and untreated) binder samples as a function of pH and time are shown in FIG. 2.

[0082] An additional sample comprising 70 wt. % binder solids prepared by combing, by dry weight, 23 wt. % hexamethylenediamine (HMDA) and 70 wt. % high fructose corn syrup (described herein as “H7023”) was produced and evaluated. This sample (comprising a decreased concentration of polyamine) was disadvantageously observed to gel to an increased degree and/or at an enhanced rate versus the H7030 composition, which suggests that the additional polyamine concentration comprising the H7030 sample may provide thermal and/or temporal stability under certain processing, transporting and/or storage conditions versus a sample with a decreased polyamine concentration, e.g. H7023.

EXAMPLE 4. USER OF BINDER COMPOSITION FOR ENHANCING CORRUGATED BOARD/CARDBOARD PERFORMANCE

[0083] In an effort to improve the performance of starch comprising, corrugated cardboard articles and manufacturing processes for producing these articles, a 50 wt. % solids composition was prepared by combining, by dry weight, and 19 wt. % 4-(aminomethyl)-1,8-octanediamine (AMOD)—commercially available as Hexatran™ from Ascend Performance Materials and 81 wt. % high fructose corn syrup, hereinafter referred to as “T5019,” was prepared. It was observed that this composition was stable under ambient temperature/pressure conditions on a benchtop for at least about four (4) months. A batch of T5019 was then treated with a sufficient concentration of CO.sub.2 to produce a compositional pH of about 8.8. The resulting composition is hereinafter described as “MaxxLink® Gold”.

[0084] The MaxxLink® Gold composition was incorporated in a corrugated produce cardboard box at a concentration of 2.0% (weight/weight) as a waterproofing agent for starch based compositions and compared to a corrugated produce cardboard box comprising MaxxLink® XL-5000, a general purpose, ketone formaldehyde based resin used as a waterproofing agent for starch based compositions (commercially available from MCTRON™ Technologies, Greenville, S.C., USA). The performance of the corrugated produce cardboard box was measured via a pin adhesion, alternatively referred to as a “wet pin adhesion” or simply “wet pins” test (see, for example, 1) https://imisrise.tappi.org/TAPPI/Products/01/T/0104T845.aspx; and 2) https://www.westpak.com/page/material-analysis/material-analysis-pin-adhesion). In certain embodiments, an ideal “wet pins” quantitative performance value for the disclosed trial is in the range of about 2 to about 6, including about 4 to about 5. The results are shown in Table 6 below:

TABLE-US-00006 TABLE 6 MaxxLink XL-5000 MaxxLink Gold Board Caliper 0.27 0.27 Edge Crush 71.4 72.4 DB Dry Pins 54.9 55.8 SF Dry Pins 61.8 66.6 DB Wet Pins 3.08 3.33 SF Wet Pins 4.29 2.15

EXAMPLE 5. ALTERNATIVE BINDER

[0085] In additional trials, the performance of the disclosed binder was evaluated in comparison with N-methylolacrylamide (N-MA; molecular formula: C.sub.4H.sub.7NO.sub.2) and formaldehyde containing formulations. N-MA is used commercially in adhesives, binders, coatings and resins, including its use in latex based compositions. Commercial articles comprising N-MA may comprise significant concentrations, e.g. 200 ppm and greater, of formaldehyde, while generating and emitting significant levels of formaldehyde during manufacturing processes associated with N-MA.

[0086] As a potential substitute for a binder composition comprising N-MA and a PVAc resin, a binder comprising Maillard reactants (“H5023” as described herein) and polyvinyl acetate (PVAc) was prepared and compared to 1) an N-MA/PVAc binder; and 2) unmodified PVAc. Physicochemical performance was evaluated, specifically heat (via a “hot stiffness” test, a subjective measure of fabric cutting ease) and solvent resistance, wherein the weight fraction of the composition that dissolves in acetone after an hour is measured (wherein increased percentages of insoluble correlate to increased solvent resistance). As shown in Table 7 below, the Maillard reactants modified PVAc binder demonstrated comparable performance to the N-MA/PVAc binder, as well as improved solvent resistance versus the PVAc control. In addition, the Maillard reactants modified PVAc binder beneficially demonstrates a significant reduction in formaldehyde production as measured by the American Association of Textile Colorants and Chemists (AATCC) Test Method TM112 (https://www.aatcc.org/test/methods/).

TABLE-US-00007 TABLE 7 N-MA Modified Unmodified Maillard reactants PVAc PVAc Modified PVAc Percentage of 91.3 68.4 93.8 Insolubles in Acetone Hot Stiffness Very Good Poor Very Good Free Formaldehyde, 513 ppm <20 ppm <20 ppm wet

EXAMPLE 6. USE OF CARBONIC ACID/CO.SUB.2 .FOR IMPROVING BINDER PERFORMANCE

[0087] In additional experiments, a 54% (final) solids binder was prepared using a pre-mix of water and a H5223 binder solution (52% (initial) binder solids and 25% hexamethylenediamine (HMDA)). A sufficient volume of carbon dioxide (CO.sub.2) was then bubbled through the solution to a produce a final CO.sub.2 concentration of 2%, which facilitates the partial neutralize of the final solution. This pre-mix was removed from the reactor, mixed with a 70% (volume/volume) aqueous solution of high fructose corn syrup (HFCS), and re-introduced to the reactor, which was maintained at a temperature below 30° C. The resulting binder demonstrated a shelf-life under ambient temperature and pressure conditions of about 90 days, and is highly reactive as a thermosettable binder when cured on a production line at temperatures above 150° C.

TABLE-US-00008 TABLE 8 Component Wet Weight Percentage Dry Weight Percentage Water 25.2% 0.0% HMDA (70%) 16.0% 11.2% CO.sub.2 4.6% 4.6% HFCS (71%) 54.2% 38.4% Total 100.0% 54.2%

[0088] In alternative embodiments, latex may further be utilized to enhance the performance of articles such as corrugated cardboard, for applications where performance issues including but not limited to binder failure and low temperature pins are observed.