WO2008028923A1

WO2008028923A1 - Aqueous binder composition for mineral fibres

Info

Publication number: WO2008028923A1
Application number: PCT/EP2007/059278
Authority: WO
Inventors: Mads Gudik-Sorensen
Original assignee: Rockwool International A/S
Priority date: 2006-09-06
Filing date: 2007-09-05
Publication date: 2008-03-13
Also published as: AU2007293894A1; US20100292354A1; ES2405313T3; AU2007293894B2; RU2446119C2; PL2059118T3; US8044168B2; WO2008028923A8; EP2059118A1; RU2009112398A; EP2059118B1; EP1897433A1; CA2662015A1

Abstract

An aqueous binder composition for mineral fibres comprises a water-soluble binder component obtainable by reacting, in one or more steps, at least one alkanolamine, at least one carboxylic anhydride and at least one polyalkylene glycol component selected from polyalkylene glycols, copolymers and derivates thereof and, optionally, treating the reaction product with a base.

Description

AQUEOUS BINDER COMPOSITION FOR MINERAL FIBRES

Field of the Invention

The present invention relates to an aqueous formaldehyde-free binder composition for mineral fibres, a method of producing a bonded mineral fibre product using said binder, and a mineral fibre product comprising mineral fibres in contact with the cured binder.

Background of the Invention

Mineral fibre products generally comprise man-made vitreous fibres (MMVF) such as, e g , glass fibres, ceramic fibres, basalt fibres, slag wool, mineral wool and stone wool, which are bonded together by a cured thermoset polymeric binder material For use as thermal or acoustical insulation products, bonded mineral fibre mats are generally produced by converting a melt made of suitable raw materials to fibres in conventional manner, for instance by a spinning cup process or by a cascade rotor process. The fibres are blown into a forming chamber and, while airborne and while still hot, are sprayed with a binder solution and randomly deposited as a mat or web onto a travelling conveyor The fibre mat is then transferred to a curing oven where heated air is blown through the mat to cure the binder and rigidly bond the mineral fibres together

In the past, the binder resins of choice have been phenol/formaldehyde resins which can be economically produced and can be extended with urea prior to use as a binder However, the desire to minimize Volatile Organic Compound (VOC) emissions from products in conjunction with existing and proposed legislation directed to the lowering or elimination of formaldehyde have led to the development of formaldehyde-free binders such as, for instance, the binder compositions based on polycarboxy polymers and polyols, as disclosed in EP-A-583086, EP-A-990727 and US-A-5,318,990..

Another group of non-phenol/formaldehyde binders for mineral fibres are the addition/elimination reaction products of aliphatic and/or aromatic anhyrides with aikanolamines, e g, as disclosed in WO 99/36368, WO 01/05725, WO 01/96460, WO 02/06178, WO 2004/007615 and WO 2006/061249 These mineral fibre binders are water soluble and exhibit excellent binding properties in terms of curing speed and curing density. However, despite these disclosures, there is a continuing need for identifying new formaldehyde-free, curable aqueous compositions suitable for use as a binder for mineral fibre products.

A type of product suffering from similar environmental problems associated with conventional pheπoi/formaldehyde binders are growth substrates for plants which are based upon man-made vitreous fibres or other porous substrates; see, for instance, GB-A-1336426, These substrates may, e g, be provided in the form of slabs, blocks, plugs or other coherent products or in the form of granulate.

Conventional plant growth products generally comprise a binder, often a phenol-formaldehyde resin or urea-formaldehyde resin, which provides integrity to the product After application of the binder, the products are subjected to curing at high temperatures in a curing oven. It is essential that these plant growth substrates are able to take up and hold water, and therefore a certain wettability is required Phenol-formaldehyde resins, and to lesser degree urea-formaldehyde resins are, however, found to impart water repellency to mineral wool products and, therefore, it is well-known to include a wetting agent in the plant growth substrate in order to achieve the desired hydrophilicity and wettability; see, for instance, WO 92/04824 and WO 01/82683 Such wetting agents must exhibit good environmental compatibility, in particular, low phytotoxicity Moreover, in view of the working conditions employed during production of the plant growth substrates, they must have good thermal stability and also provide products having proper wet and dry compression strength in addition to the desired water-uptake capacity and water retaining capacity

However, over time conventional wetting agents often are washed out of the plant growth substrate leaving a product of insufficient wettability and water retaining capacity.

Summary of the Invention

Accordingly, it is an object of the present invention to provide an aqueous binder composition which is particularly suitable for bonding mineral fibres, which exhibits excellent binding characteristics in terms of curing speed and strength, has good water solubility and dilutability and is capable of providing bonded mineral fibre products with reduced or no emission of hazardous substances

A further object of the present invention is to provide a mineral fibre product bonded with such a binder composition

A particular object of the present invention is to provide a hydrophilic binder system which is particularly useful for bonding porous and especially fibrous substrates suitable for agricultural and horticultural purposes, for instance, as a plant growth substrate The hydrophilic binder system should not be readily washed out of the bonded products by aqueous media and provide bonded products having improved long-term wettability, water uptake capacity and sinking time.

Another object of the present invention is to provide a process for preparing the hydrophilic binder system.

Still another object of the present invention is to provide bonded porous substrate products, for instance, plant growth substrates, having improved long-term wettability, water uptake capacity and sinking time.

In accordance with a first aspect of the present invention, there is provided an aqueous binder composition for mineral fibres comprising a water-soluble binder component obtainable by reacting, in one or more steps, at least one alkanolamine, at least one carboxylic anhydride and at least one polyalkylene glycol component selected from polyalkylene glycols, copolymers and derivates thereof and, optionally, treating the reaction product with a base.

In accordance with a second aspect of the present invention, there is provided a method of producing a bonded mineral fibre product which comprises the steps of contacting the mineral fibres or mineral fibre product with an aqueous binder composition as defined above, and curing the binder composition.

In accordance with a third aspect of the present invention, there is provided a mineral fibre product comprising mineral fibres in contact with the cured binder composition defined above In accordance with a fourth aspect of the present invention, there are provided bonded porous substrates, including plant growth substrate products, which comprise the cured binder composition defined above Description of the Preferred Embodiments

The formaldehyde-free aqueous binder composition according to the present invention comprises a water-soluble binder component obtainable by reacting, in one or more steps, at least one alkanolamine, at least one carboxylic anhydride and at least one pofyalkylene glycol component selected from polyalkylene glycols, copolymers and derivates thereof and, optionally, treating the reaction product with a base

In a specific embodiment of the present invention, the polyalkylene glycol component is pre-reacted with an acid component (C) selected from di- and polycarboxyiic acids and anhydrides thereof to form a polyalkyfene glycol ester having carboxylic acid functionality

The alkanolamine, carboxylic anhydride, polyalkylene glycol and optional acid components may be reacted in a number of different ways, including the following

In one embodiment, the binder composition is obtainable by a) reacting a carboxylic anhydride (A), the alkanolamine and the polyalkylene glycol component, b) reacting the reaction mixture obtained in step (a) with a carboxylic anhydride (B), and c) optionally, treating the reaction product with a base

In another embodiment of the present invention, the binder composition is obtainable by a) reacting the alkanolamine and a carboxylic anhydride (A), b) reacting the reaction mixture obtained in step (a) with a carboxylic anhydride (B) and the polyalkylene glycol component, and c) optionally, treating the reaction product with a base

In this embodiment of the invention, the carboxylic anhydride (B) and the polyalkylene glycol component may be reacted together in a single stage or separately in consecutive stages In still another embodiment of the present invention, the binder composition is obtainable by a) reacting the polyalkyiene glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof to form a polyalkylene glycol ester having carboxylic acid functionality, b) reacting the reaction mixture obtained in step (a) with the alkanolamine and a carboxylic anhydride (A), c) reacting the reaction mixture obtained in step (b) with a carboxylic anhydride (B)₁ and d) optionally, treating the reaction product with a base

In a further embodiment of the present invention, the binder composition is obtainable by a) reacting the polyalkylene glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof to form a polyalkylene glycol ester having carboxylic acid functionality, b) reacting the reaction mixture obtained in step (a) with the alkanolamine and a carboxylic anhydride (A), c) reacting the reaction mixture obtained in step (b) with carboxylic anhydride (B), and d) optionally, treating the reaction product with a base..

In another embodiment of the present invention, the binder composition is obtainable by a) reacting the alkanolamine with a carboxylic anhydride (A), b) reacting the reaction mixture obtained in step (a) with a carboxylic anhydride (B), c) reacting the polyalkylene glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof to form a polyalkylene glycol ester having carboxylic acid functionality, d) combining the reaction mixtures obtained in steps (b) and (c), and e) optionally, treating the reaction product with a base.. In still another embodiment of the present invention, the binder composition is obtainable by a) reacting the alkanolamine with a carboxylic anhydride (A), b) reacting the reaction mixture obtained in step (a) with a carboxylic anhydride (B) and a polyalkylene glycol ester having carboxylic acid functionality obtained by reacting the polyalkylene glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof, and c) optionally, treating the reaction product with a base

In a further embodiment of the present invention, the binder composition is obtainable by a) reacting an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof, the alkanolamine and the polyalkylene glycol component, b) reacting the reaction mixture obtained in step (a) with a carboxyϋc anhydride (A), c) reacting the reaction mixture obtained in step (b) with a carboxylic anhydride (B), and d) optionally, treating the reaction product with a base,

It should however be noted that the present invention is not limited to the above-mentioned preferred embodiments but encompasses various other reaction sequences involving the reaction of alkanolamine, carboxylic anhydride, polyalkylene glycol and optional acid components.

Alkanolamine

The preferred alkanolamines for use in the preparation of the binder composition according to the present invention are alkanolamines having at least two hydroxy groups such as, for instance, alkanolamines represented by the formula

R²

! R¹ — N — R³ wherein R¹ is hydrogen, a CM_O alkyl group or a C^-io hydroxyafkyl group; and R² and R³ are Ci_io hydroxyalkyl groups

Preferably, R² and R³, independently are C₂-₅ hydroxyalkyl groups, and R¹ is hydrogen, a Ci_-S alkyl group or a C₂-₅ hydroxyalkyl group Particularly preferred hydroxyalkyl groups are β- hydroxyalkyl groups

Specific examples of suitable alkanolamines are diethanolamine, triethanolamine, diisopropaπolamiπe, triisopropanolamine, methyidiethanolamine, ethyldiethanolamine, n-butyldiethanolamine, methyldiisopropanolamine, ethyl- isopropanolamine, ethyldiisopropanolamine, 3-amino-1 ,2-propanediol, 2-amino-1 ,3- propanediol and tris(hydroxymethyl)aminomethane Diethanolamine is the currently preferred alkanolamine

In accordance with the present invention, glycerol may be used in addition to, or as a replacement of, the alkanoiamine Up to 100%, preferably 10% to 99 or 100% and, more preferably, 25% to 90% of the alkanolamine may be replaced by glycerol

Carboxylic anhydride

The carboxylic anhydride reactant may be selected from saturated or unsaturated aliphatic and cycloaliphatic anhydrides, aromatic anhydrides and mixtures thereof, saturated or unsaturated cycloaliphatic anhydrides, aromatic anhydrides and mixtures thereof being preferred

In the above-mentioned preferred embodiments of the invention, the carboxylic anhydrides (A) and (B) are the same or different and are independently selected from cycloaliphatic and aromatic anhydrides or mixtures thereof

For example, one of the carboxylic anhydrides (A) and (B) may be a cycloaliphatic anhydride and the other an aromatic anhydride In a preferred embodiment, both carboxylic anhydrides (A) and (B) are the same or different aromatic anhydrides

Specific examples of suitable aliphatic carboxylic anhydrides are succinic anhydride, maleic anhydride and glutaric anhydride Specific examples of suitable cycloaliphatic anhydrides are tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride and nadic anhydride, i e endo-cis- bicyc!o[2 2 1]-5-heptene-2,3-dicarboxylic anhydride Specific examples of suitable aromatic anhydrides are phthalic anhydride, methylphthalic anhydride, trimellitic anhydride and pyromellitic dianhydride

Polyalkylene glycol component The polyalkylene glycol component used in the preparation of the binder composition according to the present invention is preferably selected from polyalkyfene glycols such as polyethylene glycol (PEG), polypropylene glycol (PPG), polybutylene glycol (PBG) and mixtures and copolymers thereof Also suitable are polyalkylene glycol derivatives including but not limited to polyalkylene glycol ethers and esters such as, for instance, mono alkyl ethers and esters, e g methyi PEG, ethyl PEG, propyl PEG, butyl PEG and mixtures and copolymers thereof.

The polyalkylene glycol component preferably has a molecular weight of between 150 and 20,000; more preferably between 150 and 10,000; in particular, between 200 and 5,000; and most preferably, between 300 and 1 ,000 Specific examples of commercially available polyalkylene glycol components are PEG 200, PEG 300, PEG 400, PEG 600, PEG 800, PEG 1000, PEG 2000, PEG 500O₁ PEG 10000, PEG 20000, and PEG 50000

Acid component The optionally used acid component (C) is at least one di- or polycarboxylic acid or an anhydride thereof The acid component is preferably selected from aliphatic, cycloaliphatic, saturated, unsaturated and aromatic carboxylic acids and anhydrides

More preferably, the acid component is selected from aliphatic di- or polycarboxylic acids, including saturated di- or polycarboxylic acids having 3 to 7 carbon atoms, such as succinic acid, glutaric acid, adipic acid, citric acid and malonic acid, or anhydrides thereof; and unsaturated di- or polycarboxylic acids having 4 to 7 carbon atoms or anhydrides thereof, such as maleic acid, fumaric acid and maleic anhydride; cycloaiiphatic di- or polycarboxylic acids or anhydrides thereof, such as tetrahydrophthalic acid, hexahydrophthalic acid and methyltetrahydrophthalic acid and the corresponding anhydrides; aromatic di- or polycarboxyϋc acids or anhydrides thereof, such as phthaϋc acid, methylphthalic acid, trimeϋitic acid, pyromellitic acid and the corresponding anhydrides Reaction conditions

In the preparation of the binder composition, the proportion of the afkanolamine, carboxylic anhydride, polyalkylene glycol and optional acid reactants is preferably selected such that the ratio of equivalents of amine plus hydroxy groups (NH+OH)^" to equivalents of carboxy groups (COOH) is within the range of about 0 4 to 2 0, more preferably about 0.6 to 1 75, and most preferably about 1 0 to 1 75

The polyalkylene glycol component is preferably used in amounts of up to 30%, taken as weight percentage of the dry solid binder, preferably in an amount of from about 0 01 to about 20%, more preferably about 0.1 to about 10% If glycerol is used in the reaction, its amount is preferably such that the equivalent ratio of glycerol OH groups to total equivalents of amine groups plus hydroxy groups (NH+OH) is 0.2 to 0.9, preferably 0.3 to 0.8 and, more preferably, 0 5 to 0 8

The reaction between the alkanolamine, carboxylic anhydride, polyalkylene glycol and optional acid reactants is generally carried out at a reaction temperature of between room temperature and the boiling point of any solvent employed or the boiling point of any of the reactants, preferably at a reaction temperature of at least about 50⁰C and up to about 200⁰C In a preferred embodiment and, in particular, when two different anhydrides are employed, the alkanolamine is first heated to a temperature of at least about 50⁰C, then the first anhydride is added and the reaction temperature is raised to at least about 70°C, preferably at least about 95⁰C and more preferably at least about 125°C, at which temperature the second anhydride is added to the reaction mixture when substantially all the first anhydride has dissolved and/or reacted. Increasing the reaction temperature from 70-95⁰C to 100-200⁰C allows a higher conversion of monomers to oligomers In this case, a preferred temperature range is 105-170⁰C, more preferably 110-150^cC.

The reaction may optionally be carried out in the presence of a catalyst, preferably an amine catalyst such as, e,g , an aliphatic amine like triethylamine or an aromatic or heterocyclic amine like imidazole Optionally, the reaction may also be carried out in the presence of an aprotic, polar solvent such as a ketone like acetone, an ether like tetrahydrofurane, an ester like acetoacetate, or an amine like pyridine. Water may be added after the first anhydride has reacted, either together with the second anhydride or before addition of the second anhydride, or at the end of the reaction in order to stop the reaction and to make the binder easily pumpable.

In order to improve the water solubility and dilutability of the binder, a base may be added up to a pH of about 8, preferably a pH of between about 5-8, and more preferably a pH of about 6-7 Furthermore, the addition of a base will cause at least partial neutralization of unreacted acids and a concomitant reduction of corrosiveness Normally, the base will be added in an amount sufficient to achieve the desired water solubility or dilutabiϋty The base is preferably selected from volatile bases which will evaporate at or below curing temperature and hence will not influence curing Specific examples of suitable bases are ammonia (NH₃) and organic amines such as diethanolamine, triethanolamine and dimethylethanolamine The base is preferably added to the reaction mixture after the reaction has been actively stopped by adding water. Furthermore, one or more polycarboxy crosslinking agents may be added after termination of the reaction and, optionally, together with the base. Suitable polycarboxy crosslinking agents are, e g , homopolymers and copolymers of acidic monomers such as acrylic acid, alkylacrylic acid (e.g . methacrylic acid) and maleic acid, and copolymers of such acidic monomers and acrylates. The weight percentage of these polycarboxy crosslinking agents is at least 0 5, preferably at least 10 wt ..%, and up to 50, preferably up to 30 wt %, more preferably up to 15 wt %, based on the binder composition.

Other Components The binder composition according to the present invention may comprise one or more conventional binder additives

These include, for instance, silanes such as, e g., γ-aminopropyltriethoxy- silaπe, curing accelerators such as, e g , β-hydroxylalkylamides; the free acid and salt forms of phosphoric acid, phosphonic acid, phosphinic acid, citric acid and adipic acid Other strong acids such as boric acid, sulphuric acid, nitric acid and p- toiuenesulphonic acid may also be used, either alone or in combination with the just mentioned acids, in particular with phosphoric, phosphonic or phosphinic acid Other suitable binder additives are thermal stabilizers; UV stabilizers; hydrolytic stability- improving agents such as monoaikanolamines, ailylamines, peroxy compounds, epoxy compounds, compounds having at least one long-chain aliphatic moiety and at least one functional group, and SBR latices; surface active agents; fillers such as clay, silicates, and magnesium sulfate; pigments such as titanium dioxide; corrosion inhibitors; urea; silica; magnesium hydroxide and others

These binder additives and adjuvants are used in conventional amounts generally not exceeding 20 % by weight of the binder solids The amount of curing accelerator in the binder composition is generally between 0.05 to 5 wt.%, based on solids, and also the amount of silanes is generally between 0.05 to 5 wt .%. If appropriate, co-binders such as, e g , carbohydrates may be employed in amounts of, for instance, up to 25-30 wt.%, based on binder solids

Fina! Binder Composition

The binder composition according to the present invention preferably has a solids content of from 10 to 40 wt % This is often the concentration range of the binder in storage containers before use.

In a form ready for application, the binder preferably has a solids content of from 1 to 30 wt %

For transportation, a solids content of the binder composition of from 60 to 75 wt % is frequently employed..

In order to achieve adequate application properties and, in particular, spraying properties, the viscosity of the binder composition may be adjusted This is accomplished, for instance, by controlling the type and concentration of binder components in the aqueous binder system. Viscosity may be kept within the desired ranges e.g . by controlling the molecular weight of binder component (lower reaction temperature, stopping the reaction by adding water at an earlier reaction stage, etc.), and by properly adjusting the relative amounts of the binder components and water solvent

Mineral fibre product

The formaldehyde-free aqueous binder composition according to the present invention may be applied to mineral fibres or mineral fibre products by conventional techniques such as, e.g ., air or airless spraying, rotating disc atomizatioπ, padding, saturating, roll coating, curtain coating, beater deposition, or the like

The mineral fibres may be any of man-made vitreous fibres (MMVF), glass fibres, ceramic fibres, basalt fibres, slag wooi, rock wool, stone wool and others. The mineral fibre products are, for instance, woven and nonwoven fabrics, mats, batts, slabs, sheets and other shaped articles which find use, for example, as acoustic insulation materials, filter stock, and in other applications

For the manufacture of acoustic insulation products and horticultural products, the binder is normally applied in an amount of 0.1 to 15 %, preferably 0 3-10 %, of the bonded mineral fibre product.

In general, the binder composition is applied, normally by spraying, immediately after fiberization of the mineral melt, whereupon the coated mineral wool is cured in a curing oven wherein heated air is passed through the mineral wool web to cure the binder Typically, the curing oven is operated at a temperature of from about 200⁰C to about 35O⁰C Preferably, the curing temperature ranges from about 200⁰C to about 300⁰C, and more preferably from about 225 to about 290⁰C. Generally, the curing oven residence time is from 30 seconds to 20 minutes, depending on, for instance, the product density

Besides conventional curing by heat (e g heated air) other curing methods may be used, for example curing with microwave or infrared radiation If desired, the mineral wool web may also be subjected to a shaping process before curing

The bonded mineral fibre product emerging from the curing oven in the form of e g . a batt may be cut to a desired format and, if appropriate, compressed for packaging and shipping It may also be employed as an intermediate for the manufacture of shaped articles and composite materials.

Although the formaldehyde-free aqueous binder composition according to the present invention is particularly useful for bonding mineral fibres, it may equally be employed in other applications typical for binders and sizing agents, e g as a binder for foundry sand, glass fibre tissue, ceilulosic fibres, non-woven paper products, composites, molded articles, coatings etc

Another field of application of particular interest is the production of porous and especially fibrous bonded substrates suitable for agricultural and horticultural purposes, for instance, as a plant growth substrate In that instance, the porous substrate may be selected from any substrate which is conventionally employed for agricultural and horticultural purposes and, in particular, for plant growth substrates Specific examples of suitable substrate materials are, for instance, man-made vitreous fibres such as mineral wool, stone wool, glass wool or slag wool; natural fibres, particularly plant fibres such as coco fibres and cotton; cellulosic and lignocellulosic fibres; and inorganic materials such as perlite beads and intumescent inorganic materials

After application of the binder system according to the present invention to the porous substrate, the bonded product is cured employing the curing conditions described above When using natural fibres or other organic materials as a substrate, the curing temperature should, of course, not be above the decomposition or burning temperature of these materials.

After curing, the bonded substrate may be cut or shaped into a desired form such as, e g , slabs, mats, blocks, plugs, cubes or the like The bonded porous product obtained is useful for agricultural, horticultural and architectural purposes, for instance, as a plant growth material and for roof gardens In order to prepare a plant growth material, the bonded porous product may be combined in the usual manner with other composite layers (wrapping foil etc ) and additives such as, for instance, nutrients/fertilizers and fillers like, e g , clay Owing to their improved hydrophilicity, the bonded porous products according to the present invention are of particular use in plant growth environments as disclosed in WO 2004/017718 A1 comprising a first growth substrate which has a first water uptake capacity and a first sinking time, and the first growth substrate is in fluid communication with a discrete second substrate which has a second water uptake capacity lower than the first water uptake capacity and a second sinking time shorter than the first sinking time. "Water uptake capacity" and "sinking time" are as defined in WO 2004/017718 A1 with a lower sinking time representing a greater hydrophilicity value Thus, the second substrate preferably has a degree of hydrophilicity when dry which is greater than that of the first growth substrate. Preferably the two substrates are contained in a plant growth container such as a pot. The system is adapted so that plants may be positioned for growth in the first growth substrate, which is preferably peat or coir. The following examples are intended to further illustrate the aqueous binder composition and the use thereof as a binder for mineral fibre products Parts and percentages are by weight, unless indicated otherwise The solids content is determined in accordance with DIN 16916, Part 2, Section 5 13, with the modification that the sample is heated at 200⁰C for one hour.

In the examples, the following abbreviations are used:

DEA: diethanolamine

PTA: phthalic anhydride

THPA: tetrahydrophthaiic anhydride

TMA: trimellitic anhydride

PEG: polyethylene glycol

Example 1

18 g of PEG 300 (7.5% w/w based on binder dry solids) and 13.3 g of PTA are placed in a round-bottomed reaction flask fitted with a mechanical stirrer. The mixture is allowed to react at 95°C for 16 hours Then, additional 89 1 g of PTA are added together with 105 g of DEA, and the reaction temperature is allowed to rise to 130⁰C After 45 minutes, 57 6 g of TMA are added and the temperature is maintained for 1 hour. The reaction mixture is cooled to 1 10⁰C, and 147 g of water are added, The mixture is stirred at 70⁰C for 1 hour after which it is cooled to ambient temperature Then, 4.6 g of phosphinic acid and 46 ml of a 25% aqueous ammonia solution are added under stirring After adding 2 g of amino silane, water is added until a dilution of the binder composition of 18% dry solids is obtained

Example 2

105 g of DEA are placed in a round-bottomed reaction flask fitted with a mechanical stirrer and heated to 60⁰C. 97.3 g of THPA are then added in small portions, and the reaction temperature is raised to 13O⁰C. The mixture is allowed to react for 45 minutes after which 57.6 g of TMA and 6 g of PEG 400 (2 5% w/w based on binder dry solids) are added The mixture reacts further for one hour after which it is cooled to 11 OX, and 147 g of water are slowly added to the reaction mixture and stirred until a tan dear mixture is obtained Then, 4,6 g of phosphinic acid and 39 ml of a 25% aqueous ammonia solution are added under stirring Water is added until a dilution of the binder composition of 18% dry solids is obtained

Example 3

Mixture A

105 g of DEA are placed in a round-bottomed reaction flask fitted with a mechanical stirrer and heated to 60⁰C 91 ,3 g of THPA are then added in small portions, and the reaction temperature is raised to 130^cC The mixture is allowed to react for 45 minutes after which 57.6 g of TMA are added. The mixture reacts further for one hour after which it is cooled to 11O⁰C, 147 g of water are slowly added to the reaction mixture and stirred until a tan clear mixture is obtained The isolated resin cooled to ambient temperature.

Mixture B

A reaction product is made by adding 19 8 g of PTA to 40 1g of PEG 600 (5% w/w based on binder dry solids) in a round-bottomed reaction flask fitted with a mechanical stirrer. The mixture is allowed to react at 95°C for 16 hours, and then cooled.

The finished binder composition is made by combining 10 1 g of Mixture A and 0 4 g of Mixture B and adding to this mixture 0 12 g of phosphinic acid and 1.2 ml of a 25% aqueous ammonia solution as well as 18 g of water

Claims

C L A I M S

1 An aqueous binder composition for mineral fibres comprising a water-soluble binder component obtainable by reacting, in one or more steps, at least one alkanolamine, at least one carboxyiic anhydride and at least one polyalkylene glycol component selected from polyalkylene glycols, copolymers and derivates thereof and, optionally, treating the reaction product with a base.

The binder composition of claim 1 , wherein the polyalkylene glycol component has been pre-reacted with an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof to form a polyalkylene glycol ester having carboxyiic acid functionality

The binder composition of claim 1 , obtainable by a) reacting a carboxyiic anhydride (A), the alkanolamine and the polyalkylene glycol component, b) reacting the reaction mixture obtained in step (a) with a carboxyjic anhydride (B), and c) optionally, treating the reaction product with a base.

The binder composition of claim 1 , obtainable by a) reacting the alkanolamine and a carboxyiic anhydride (A), b) reacting the reaction mixture obtained in step (a) with a carboxyiic anhydride (B) and the polyalkylene glycol component, and c) optionally, treating the reaction product with a base , The binder composition of claim 4, wherein, in step (b), the carboxyiic anhydride (B) and the polyalkylene glycol component are reacted in a single stage or in consecutive stages

The binder composition of claim 2, obtainable by a) reacting the polyalkylene glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof to form a polyalkylene glycol ester having carboxylic acid functionality, b) reacting the reaction mixture obtained in step (a) with the alkanolamine and a carboxylic anhydride (A), c) reacting the reaction mixture obtained in step (b) with a carboxylic anhydride (B), and d) optionally, treating the reaction product with a base..

7. The binder composition of claim 2, obtainable by a) reacting the polyalkylene glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof to form a polyalkylene glycol ester having carboxylic acid functionality, b) reacting the reaction mixture obtained in step (a) with the alkanolamine and a carboxylic anhydride (A), c) reacting the reaction mixture obtained in step (b) with a carboxylic anhydride (B), and d) optionally, treating the reaction product with a base.

8 The binder composition of claim 2, obtainable by a) reacting the alkanolamine with a carboxylic anhydride (A), b)reacting the reaction mixture obtained in step (a) with a carboxylic anhydride

(B), c) reacting the polyalkylene glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof to form a polyalkylene glycol ester having carboxylic acid functionality, d) combining the reaction mixtures obtained in steps (b) and (c), and e) optionally, treating the reaction product with a base

9 The binder composition of claim 2, obtainable by a) reacting the alkanolamine with a carboxylic anhydride (A), b) reacting the reaction mixture obtained in step (a) with a carboxylic anhydride (B) and a polyalkyiene glycol ester having carboxylic acid functionality obtained by reacting the polyalkyleπe glycol component and an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof, and c) optionally, treating the reaction product with a base

10. The binder composition of claim 1 , obtainable by a) reacting an acid component (C) selected from di- and polycarboxylic acids and anhydrides thereof, the alkanolamine and the polyalkylene glycol component, b) reacting the reaction mixture obtained in step (a) with a carboxylic anhydride (A), c) reacting the reaction mixture obtained in step (b) with a carboxylic anhydride (B), and d) optionally, treating the reaction product with a base.

11 The binder composition of any one of claims 1 to 10, wherein the polyalkylene glycol component is at least one selected from polyethylene glycol (PEG), polypropylene glycol (PPG), polybutylene glycol (PBG), copolymers and derivatives thereof

12 The binder composition of any one of claims 1 to 11 , wherein glycerol has been used in addition to, or as a replacement of, the alkanolamine

13 The binder composition of any one of claims 1 to 12, wherein the carboxylic anhydrides (A) and (B) are the same or different and are independently selected from saturated or unsaturated, aliphatic or cycloaiiphatic anhydrides and aromatic anhydrides or mixtures thereof

14 The binder composition of claim 13, wherein one of the carboxylic anhydrides (A) and (B) is a cycloaiiphatic anhydride and the other is an aromatic anhydride. 15 The binder composition of claim 13, wherein the carboxylic anhydrides (A) and (B) are the same or different aromatic anhydrides

16. The binder composition of any one of claims 13 or 14, wherein the cycloaliphatic anhydrides are selected from tetrahydrophthalic anhydride, hexahydrophthalic anhydride and methyl-tetrahydrophthalic anhydride.

17. The binder composition of any one of claims 13 to 15, wherein the aromatic anhydrides are selected from phthalic anhydride, methylphthaiic anhydride, trimellitic anhydride and pyromellitic dianhydride

18 The binder composition of any one of claims 2 to 17, wherein the acid component (C) is selected from di- or polycarboxylic acids or corresponding anhydrides, preferably aliphatic, cycloaliphatic, saturated, unsaturated and aromatic carboxylic acids and anhydrides.

19. The binder composition of claim 18, wherein the di- or polycarboxylic acids or anhydrides are selected from maleic acid, fumaric acid, tetrahydrophthalic acid, hexahydrophthaiic acid, methyl-tetrahydrophthaiic acid, phthaϋc acid, methylphthaiic acid, trimellitic acid, pyromellitic acid and the corresponding anhydrides.

20. The binder composition of any one of claims 1 to 19, wherein the alkanolamine is selected from diethanolamine, triethanolamine, dϋsopropanolamine, triisopropanolamine, methyldiethanolamine, ethyldiethanolamine, n-butyldiethanolamine, methyldiisopropanolamine, ethylisopropanolamine, ethyldiisopropanolamine, 3-amino-1 ,2-propanedioi, 2-amino-1 ,3-propanediol and tris(hydroxymethyl)aminomethane

21 The binder composition of any one of claims 1 to 20, wherein the proportion of the alkanolamine, carboxylic anhydride, polyalkylene glycol and optional acid reactants is selected such that the ratio of equivalents of amine plus hydroxy groups (NH+OH) to equivalents of carboxy groups (COOH) is within the range of about 0.4 to 2.0

22. The binder composition of any one of claims 1 to 21 , wherein the polyalkylene glycol component is used in an amount of up to 30%, taken as weight percentage of the dry solid binder

23 The binder composition of any one of claims 1 to 22, further comprising a curing accelerator and, optionally, other conventional binder additives,

24. The binder composition of claim 23 which comprises phosphinic acid as a curing accelerator

25. A method of producing a bonded mineral fibre product which comprises the steps of contacting the mineral fibres or mineral fibre product with a binder composition according to any one of claims 1 to 24, and curing the binder composition

26. The method of claim 25 wherein curing is effected at a curing temperature of from about 200⁰C to about 35O⁰C

27. Mineral fibre product comprising mineral fibres in contact with the cured binder composition according to any one of claims 1 to 24

28 A bonded porous substrate comprising a cured binder composition according to any one of claims 1 to 24

29. The bonded porous substrate of claim 28 which comprises man-made vitreous fibres or naturai fibres, including plant fibres, cellulosic and lignocellulosic fibres.

30 The bonded porous substrate of claim 28 which comprises an inorganic porous material such as perlite beads. A plant growth substrate product comprising the bonded porous substrate according to any one of claims 28 to 30

The use of a mineral fibre product according to claim 27 or of a bonded porous substrate according to any one of claims 28 to 30 or of a plant growth substrate product according to claim 31 for agricultural, horticultural and architectural purposes