RU2774883C2 - Insulation product containing mineral fibers and binder - Google Patents

Abstract

FIELD: insulation.

SUBSTANCE: invention relates to a heat- and sound-insulation product containing mineral fibers and a binder obtained as a result of curing a binder compound containing as components: a) compounds containing at least one epoxide functionality, including at least one epoxide precursor selected from aliphatic compounds containing at least two epoxide functionalities, b) a hardener selected from compounds containing at least two reactive functionalities selected from hydroxyl and carboxylic acid functionalities. For carboxylic acid functionality, it is possible to be in the form of salt or anhydride. The total weight of the binder is from 0.5 to 15% of the total weight of mineral fibers.

EFFECT: obtaining an insulation product with a binder, in which all binder components are derivatives of natural products, are non-toxic for the endocrine system and are easy-to-use for the specified purpose.

20 cl, 1 dwg, 3 tbl

Description

The present invention relates to an insulating product, in particular a heat or sound insulating product containing mineral fibers and a binder obtained by curing and/or crosslinking a binder compound containing an epoxy precursor and a hardener. The invention also relates to an aqueous binder and to a method for producing an insulating product.

Mineral fibers can be glass or stone fibers.

Insulating products may be in the form of mineral wool, felt or mesh containing glass threads.

The insulation products are preferably in the form of mineral wool. Mineral wool contains entangled mineral fibers, optionally bound with a binder. These fibers are generally obtained by using centrifugal force methods, either internal (on an element called a plate) or external (on elements called rotors), combined with stretching by a gas flow at more or less high temperature. They can also be obtained using essentially aerodynamic methods of stretching molten mineral material from a die with gaseous streams. Rock wool fibers are discrete as opposed to "textile" glass fibers, which are the result of having filaments continuously stretched under a spinneret.

When using these methods for discrete fibers, thin felts with soundproofing or filtering properties can also be obtained.

Nets containing glass threads may be woven or non-woven nets. Glass filaments contain glass fibers made from continuous filaments (or glass filaments) cut or reformed where appropriate. These fibers are produced using a stretch spinning process in which molten glass is converted into a filament by stretching at high speed.

The manufacture of insulating products based on mineral wool generally includes:

- the stage of manufacturing glass or stone fibers, for example, when using the centrifugal force method,

- the step of applying an aqueous binder compound,

- the step of collecting the fibers on the tape so as to form a web or mat,

- a thermosetting step at temperatures of more than 100° C. in a suitable heating device such as a drying oven.

The aqueous binder is evaporated on the still hot fibers at the level of the fiberising element and/or during their journey between the fiberising device and the fiber collection belt.

The resulting insulating product contains mineral wool, the fibers of which are bonded to each other using a binder obtained by curing the components of the binder compound. The binder must properly adhere to the fibers and must be homogeneously distributed in order to preferentially be subsequently found at the junctions between the fibers. Therefore, the binder is preferably sprayed while the fibers are still individualized. Therefore, spraying is carried out in a fiber collection hopper, below the burners generating the expansion gas stream. As a result, the use of flammable and/or polluting organic compounds is prohibited due to the excessive risk of fire and/or contamination in the collection bin.

In addition, the aqueous binder is serially diluted prior to being applied to the fibers. These components must be able to be uniformly distributed in the binder, regardless of the level of dilution and mixing.

Phenolic resins, commonly used as binders, are increasingly being replaced by products that do not emit or emit very little formaldehyde, which is a compound recognized as capable of causing harm to human health.

The applicant in his applications EP 0 369 848, WO 2004/007395 and WO 2005/044750 proposed binder compounds containing an amine hardener and epoxy precursor resins selected from polyglycidyl ethers.

The epoxy precursor and hardener must not react before being applied to the fibers and forming an insulating product. This means that premature crosslinking should be as weak as possible. This is because if the epoxy precursor and hardener polymerize in the storage tanks or at the level of the spray rings, this will cause a labor-intensive cleanup, but especially a production interruption.

Preferably, the epoxy precursor and hardener should not react after spraying until the fibers are collected in the form of mats. Even more preferably, the epoxy precursor and curing agent should not react before passing through the proper heating device. Finally, the epoxy precursor and curing agent must react rapidly during the thermoset reaction in the heating device.

Therefore, the onset and rate of polymerization must be perfectly controlled. In this way, the risks of premature crosslinking are avoided and it is possible to maintain a polymerization time compatible with high production rates, in particular by ensuring that the binder is fully cured after being treated in a drying oven at high temperature.

The resins disclosed in EP 0 369 848, WO 2004/007395 and WO 2005/044750 are dispersible or emulsifiable in the presence of an emulsifier or dispersant. The only resins exemplified in these applications are polyglycidyl ethers obtained from the condensation of epichlorohydrin and bisphenol.

The use of resins derived from compounds believed to be endocrine disruptors, such as bisphenol, is not entirely satisfactory.

In addition, bisphenol polyglycidyl ether resins are not water soluble. These resins are used in binder compounds in the form of an emulsion. However, the use of an emulsion in an industrial process involving large scale dilution steps and high temperature injection steps can be problematic. This is due to the need to guarantee the stability of the emulsion at each stage of the process in order to ensure that the reproducibility of the resulting insulating products is obtained.

The hardeners used in WO 2005/044750 are aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetraamine (TETA) or tetraethylenepentaamine (TERA). These compounds are capable at temperatures of less than 100° C., or even at ambient temperature, to a significant extent react with certain epoxy precursors. In addition, due to the exothermicity of the reaction, the likelihood of a reaction between the curing agent and the epoxy precursor immediately after initiation of the reaction increases exponentially.

Prior art binders containing epoxy resin in emulsion form and such amine hardeners meet the requirements for polymerization, namely, no polymerization before spraying and polymerization after spraying in the fiber collection bin, since the resins are in the form of an emulsion. Epoxy functionalities are not directly accessible as long as the emulsion remains stable. On the other hand, immediately after the injection of water and therefore its evaporation, the reactive functionalities of the curing agent and the epoxy functionalities of the resin may react with each other. The reactivity of amine hardeners with epoxy functionalities allows fast curing compatible with industrial production rates. However, the reaction generally starts as soon as spraying has taken place, and not during the curing step in a proper heating device.

There is a need to develop new epoxy resin binders that overcome the disadvantages of the prior art.

The invention proposes to obtain a binder, for which:

- epoxy precursors are not derived from compounds suspected of being endocrine disruptors such as bisphenols, and/or

- some or all of the compounds are derived or produced from natural products (bio-based), and/or

- the epoxy precursors are perfectly soluble in water or miscible with water and therefore do not form an emulsion in the binder, and/or

- the binder compound does not polymerize or polymerizes to a very small extent before being injected into the fiber collection bin, in other words:

for a sufficient period of time corresponding to normal storage times in tanks prior to injection, in particular for several hours, and

at temperatures capable of being reached during these storage and injection steps, and/or

- the binder does not polymerize or polymerizes to a very small extent before passing through an appropriate heating device, and/or

- the binder polymerizes rapidly during its passage through a suitable heating device.

The invention relates to an insulating product containing mineral fibers and a binder obtained by curing a binder compound containing as components:

a) compounds containing at least one epoxy functionality, including at least one epoxy precursor selected from aliphatic compounds containing at least two epoxy functionality, while aliphatic compounds containing at least two epoxy functionalities represent at least 50% of the total mass of compounds containing at least one epoxy functionality of the binder compound,

b) a curing agent selected from compounds containing at least two reactive functionalities selected from hydroxyl and carboxylic acid functionalities, it being possible for the carboxylic acid functionalities(s) to be in the form of a salt or an anhydride.

The invention also relates to an aqueous binder for insulating products based on mineral fibers, containing as components other than water:

a) compounds containing at least one epoxy functionality, including at least one epoxy precursor selected from aliphatic compounds containing at least two epoxy functionality, while aliphatic compounds containing at least two epoxy functionalities represent at least 50% of the total mass of compounds containing at least one epoxy functionality of the binder compound,

b) a curing agent selected from compounds containing at least two reactive functionalities selected from hydroxyl and carboxylic acid functionalities, it being possible for the carboxylic acid functionalities(s) to be in the form of a salt or an anhydride.

The invention also relates to a method for manufacturing an insulating product containing mineral fibers and a binder, where:

- an aqueous binder compound according to the invention is applied to the mineral fibres,

- the binder is obtained as a result of thermal curing of the non-volatile components of the binder.

Such binders are easy to prepare, stable and highly dilutable, and exhibit curing conditions that are compatible with the intended applications.

In the rest of the description of the invention, the features described apply equally to the bonding compound, to the insulating product and to the method of manufacturing the insulating product.

Applicant has found that certain epoxy precursors according to the invention and derived from aliphatic compounds, in contrast to epoxy precursors derived from aromatic compounds of the bisphenol type, are completely soluble in water. In contrast to emulsions, solutions are easier to prepare and their use poses few problems. Any problems associated with the stability of emulsions are eliminated.

However, in this case the use of certain amine hardeners cannot be contemplated due to their excessively high reactivity with the epoxy functionalities of the precursors. These functionalities are directly accessible as they are no longer "protected" by the emulsion.

Application WO 2005/044750 mentioned above indicates the possibility of choosing an epoxy precursor from resins that are the result of the reaction between epichlorohydrin and bisphenol A, bisphenol F, polyethylene glycols, glycerol, pentaerythritol and novolak resins and mixtures of these resins. Particularly preferred are resins resulting from the reaction between epichlorohydrin and bisphenol A, and these are the only resins that are given as an example. WO 2005/044750 also indicates the possibility of using other epoxy compounds, such as epoxidized aliphatic compounds. The level of these compounds is generally less than 30%, preferably less than 10%, by weight of the epoxy resin.

No example illustrates a binder containing epoxidized aliphatic compounds. WO 2005/044750 does not disclose a binder containing, relative to the total weight of compounds containing at least one epoxy functionality and present in the binder, at least 50% (wt.) of aliphatic compounds containing, at least two epoxy functionalities.

Conditions for polymerization, in terms of onset and rate of polymerization, of a binder containing polyglycidyl ethers of aliphatic compounds in solution as epoxy precursor and aliphatic polyamines as curing agent, are not controlled under the conditions of the intended application. This is due to the ability of these compounds to react prior to being injected into the fiber collection hopper. Indeed, the crosslinking temperature is less than 90°C or even close to ambient temperature for the most reactive polyamines. The risk of polymerization in storage tanks or injection rings is too high. In addition, the risk of crosslinking prior to application to the fibers increases the risk of insulating products of varying quality.

In accordance with the invention, the crosslinking temperature is determined using dynamic mechanical analysis (DMA). DMA analysis makes it possible to determine the viscoelastic nature of the polymer. The microfiber filter is impregnated with a binder and held horizontally between fixed fixtures. An oscillating element applied to the top face of the sample and provided with a device for measuring stress versus applied strain makes it possible to calculate the elastic modulus E'. The impregnated filter paper is heated to 250°C starting from 25°C at a rate of 4°C/min. Based on the measurement results, a graphical construction of a curve of change in the modulus of elasticity E' (in Pa) depending on temperature (in ° C) is carried out. Such a curve is shown in Figure 1. After that, the tangents to the plateau before stitching (t _p ) and to the inflection point (t _i ) are plotted graphically. The crosslinking temperature (TR) corresponds to the temperature at the intersection of the tangents to the plateau before crosslinking (t _p ) and to the inflection point (t _i ).

For these measurement results, the aqueous binders deposited on the filter have a solids content ranging from 10% to 50%, preferably about 30%.

The binder compound according to the invention is characterized, in order of increasing preference, by a crosslinking temperature greater than or equal to 90°C, greater than 100°C, greater than 110°C, or between 90 and 200°C. This means that components (a) and (b) show, in order of increasing preference, the crosslinking temperature, as determined using dynamic mechanical analysis at a heating rate of 4°C/min greater than or equal to 90°C, more than 100°C, more, than 110°C or between 90 and 200°C.

The crosslinking or curing reaction may be exothermic.

The hardeners used in accordance with the invention, and in particular those of the polycarboxylic acid or polyol type, react selectively with epoxy precursors containing aliphatic compounds depending on the temperature. Indeed, observe the following:

- quasi-inertness at a temperature lower than the threshold temperature, while said threshold temperature makes it possible to inject fibers into the collection hopper without undergoing curing,

- greater reactivity immediately after reaching the threshold temperature, which makes fast crosslinking possible.

Therefore, the threshold temperature and crosslinking kinetics are compatible with the manufacturing method of mineral wool based insulation products.

Therefore, the invention advantageously provides a binder whose epoxy precursor can be in solution rather than emulsion due to the selection of a curing agent that only selectively reacts after being injected into the fiber collection hopper, and preferably only in the heating device.

Preferably the aqueous binder is in the form of a solution. This means the water solubility of all components of the composition.

The binder compound contains at least one epoxy precursor selected from aliphatic compounds containing at least two epoxy functionality.

In accordance with the invention, the term "aliphatic compound" is intended to mean a compound that does not contain an aromatic group. An aliphatic compound is a non-cyclic or cyclic, linear or branched, saturated or unsaturated carbon-based organic compound, optionally containing other atoms such as oxygen, nitrogen or sulfur, with the exception of aromatic compounds.

An epoxy precursor based on an aliphatic compound containing at least two epoxy functionalities is characterized by an EEM (epoxy equivalent weight) value in the range between 50 and 1000, preferably between 100 and 300. The epoxy equivalent (EE) weight is the amount of epoxy precursors in grams containing one equivalent of epoxides.

Preferably, the epoxy precursors may be biobased.

Preferably the epoxy precursors are water soluble or water miscible. This means that the mixture of epoxy precursor and water is in the form of a homogeneous solution as opposed to a heterogeneous dispersion or mixture such as an emulsion. This means that there are no surfactants in the mixture of epoxy precursor and water. Thus, the epoxy precursors according to the invention can be free from surfactants.

Aliphatic compounds containing at least two epoxy functionality are, on a weight basis for the total weight of compounds containing at least one epoxy functionality, of the binder compound in order of increasing preference, at least 50%, at least , 60%, at least 70%, at least 80%, at least 90%. As used herein, the term "compound containing at least one epoxy functionality", unless otherwise indicated, will include aliphatic or aromatic compounds containing at least one epoxy functionality.

Aliphatic compounds containing at least two epoxy functionalities are represented by weight for the total weight of epoxy precursors containing at least two epoxy functionalities, in order of increasing preference, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, at least 98%, 100%. As used herein, the term "epoxy precursor containing at least two epoxy functionalities", unless otherwise indicated, will include aliphatic or aromatic compounds containing at least two epoxy functionalities.

An epoxy precursor based on an aliphatic compound containing at least two epoxy functionalities may be:

- polyglycidyl ether of an aliphatic polyol,

- aliphatic polyepoxy compound obtained by oxidation of an aliphatic compound containing at least two double bonds.

The polyglycidyl ether of an aliphatic polyol can be obtained by reacting epichlorohydrin with an aliphatic polyol. The epichlorohydrin and the aliphatic polyol may be biobased.

The aliphatic polyol may be selected from:

- glycerin,

- polyglycerols,

- inositol,

- hydrogenated sugars (such as erythritol, arabitol, xylitol, sorbitol, talit, mannitol, iditol, maltitol, isomaltitol, lactitol, cellobitol, palatinite, maltotriite),

- sorbitan and isosorbide,

- butanediol and propanediol,

- starch hydrolysates and starch hydrolyzate hydrogenation products,

- hemicellulose hydrolysates and hydrogenation products of hemicellulose hydrolyzate,

- polyols obtained as a result of the functionalization of vegetable oil,

- sucrose,

- reducing sugars such as glucose or fructose or maltose, lactose or isomalt,

- trimethylolpropane, pentaerythritol, neopentyl glycol.

The polyol can be obtained by hydrogenation of carbohydrates represented by the formula C _n (H ₂ O) _p or reducing sugars containing at least one aldehyde or ketone group (reducing group). These products, also known as hydrogenated sugars or sugar alcohols, comprise all products resulting from the reduction of a saccharide selected from monosaccharides, disaccharides, oligosaccharides and polysaccharides and mixtures of these products.

The polyol may be a hydrogenation product of a starch hydrolyzate or a hemicellulose hydrolyzate. Starch and hemicellulose are polysaccharides. Starch hydrolysates and hemicellulose hydrolysates are products obtained from the enzymatic and/or acidic hydrolysis of starch or hemicellulose.

For starch hydrolysates, the degree of hydrolysis is generally characterized by the dextrose equivalent (DE), defined as follows:

DE=100 × (number of broken glycosidic bonds)/(number of glycosidic bonds in original starch)

Preferred starch hydrolysates, prior to the hydrogenation step, have a DE value in the range between 5 and 99, and advantageously between 10 and 80.

The hydrogenation of the saccharide can be carried out using known processes that are carried out under conditions of high hydrogen pressure and temperature in the presence of a catalyst selected from elements from groups IB, IIB, IVB, VI, VII and VIII of the periodic table of elements, preferably from the group containing nickel , platinum, palladium, cobalt, molybdenum and mixtures thereof. The preferred catalyst is Raney nickel. Hydrogenation converts sugar or a mixture of sugars (starch hydrolyzate) into polyols or sugar alcohols.

Hemicelluloses contain the following polysaccharides: xylan, glucuronoxylan, arabinoxylan, glucomannan and xyloglucan.

By way of example of aliphatic polyols selected from hydrogenated sugars, there may be mentioned erythritol, arabitol, xylitol, sorbitol, mannitol, iditol, maltitol, isomaltitol, lactitol, cellobitol, palatinite, maltotriite, starch hydrolyzate hydrogenation products and hemicellulose hydrolyzate hydrogenation products.

The polyglycidyl ether of the aliphatic polyol may be selected from:

polyglycidyl ether of glycerol, polyglycidyl ether of polyglycerol, polyglycidyl ether of inositol, polyglycidyl ether of erythritol, polyglycidyl ether of arabitol, polyglycidyl ether of xylitol, polyglycidyl ether of tallit, polyglycidyl ether of sorbitol, polyglycidyl ether of mannitol, polyglycidyl ether, maltitol polyglycidyl ether, isomaltitol polyglycidyl ether, lactitol polyglycidyl ether, cellobitol polyglycidyl ether, palatinite polyglycidyl ether, maltotriite polyglycidyl ether, isosorbide polyglycidyl ether, sorbitan polyglycidyl ether, butanediol polyglycidyl ether, polyglycidyl ether butanediol, polyglycidyl ether sucrose polyglycidyl ether, glucose polyglycidyl ether, fructose polyglycidyl ether, maltose polyglycidyl ether, lactose polyglycidyl ether, isomalt polyglycidyl ether, trimethylol propane polyglycidyl ether, pentaerythritol polyglycidyl ether, and neopentyl glycol polyglycidyl ether.

The polyglycidyl ether of the aliphatic polyol can be selected from the polyglycidyl ether of starch hydrolyzate hydrogenation products or hemicellulose hydrolyzate hydrogenation products.

The polyol can be obtained from the functionalization of vegetable oil. Vegetable oils are formed in large part from triglycerides, in which the three hydroxyl groups of glycerol are esterified with fatty acids. Fatty acids may be unsaturated and/or may contain hydroxyl functionality.

To obtain a polyol from vegetable oil, for example, it is possible to carry out an epoxidation followed by hydrolysis of at least two double bonds of an unsaturated fatty acid.

Another possibility is to use a vegetable oil containing fatty acids containing an alcohol functionality and at least one double bond. The polyol is obtained by carrying out an epoxidation followed by hydrolysis of at least one double bond.

The polyglycidyl ether of the aliphatic polyol may be selected from the polyglycidyl ether of the polyol obtained by functionalization of vegetable oil.

The epoxy precursor containing at least two epoxy functionalities may be selected from an aliphatic polyepoxy compound obtained by double bond epoxidation type oxidation of a compound containing at least two double bonds. The compound containing at least two double bonds may be selected from a fatty acid, a fatty acid ester, a furan, or a terpene.

The process most widely used for double bond epoxidation uses peracetic acid produced "in situ" by reacting acetic acid with hydrogen peroxide.

The aliphatic polyepoxy compound obtained by oxidizing a double bond can be obtained by oxidizing a compound selected from a furan, a terpene, or an unsaturated vegetable oil.

The aqueous binder compound contains at least one curing agent selected from compounds containing at least two reactive functionalities selected from hydroxyl and carboxylic acid functionalities.

The hardener is preferably bio-based.

Preferably, the binder contains a hardener having a molar mass less than or equal to 1000, preferably less than or equal to 750, and advantageously less than or equal to 500 g/mol.

The hardener can be selected from:

- polyol,

- polycarboxylic acid.

The hardener may contain at least one polycarboxylic acid or a salt or anhydride of such an acid.

The hardener is selected from organic polycarboxylic acids and salts or anhydrides of these acids. The term "organic polycarboxylic acid" is intended to mean an organic acid containing at least two carboxylic acid functionalities, preferably at most 15 carboxylic acid functionalities. The organic polycarboxylic acid may be a saturated or unsaturated, branched or linear, non-polymeric or polymeric acid which is a non-cyclic, alicyclic acid or aromatic compound. It is characterized by an average molar mass generally less than or equal to 50,000, preferably less than or equal to 10,000, and advantageously less than or equal to 5,000.

The non-polymeric or monomeric polycarboxylic acid may be a dicarboxylic or tricarboxylic or tetracarboxylic acid.

Preferred dicarboxylic acids include, for example, 2,5-furandicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, malic acid, tartaric acid, tartronic acid, aspartic acid, glutamic acid, fumaric acid, itaconic acid, maleic acid, traumic acid, mesaconic acid and citraconic acid.

Other dicarboxylic acids which may optionally be used include adipic acid, pimelic acid, subic acid, azelaic acid, sebacic acid, phthalic acid and derivatives thereof, in particular those containing at least one boron or chlorine atom, tetrahydrophthalic acid and its derivatives, in particular those containing at least one chlorine atom, such as chlorendic acid, isophthalic acid, terephthalic acid.

Tricarboxylic acids include, for example, citric acid, tricarballylic acid, 1,2,4-butanetricarboxylic acid, aconitic acid, hemimellitic acid, trimellitic acid and trimesic acid.

As the tetracarboxylic acid, for example, 1,2,3,4-butanetetracarboxylic acid and pyromellitic acid can be mentioned.

Preferably, 2,5-furandicarboxylic acid, itaconic acid, citric acid and 1,2,3,4-butanetetracarboxylic acid are used.

By way of example of a polymeric organic polycarboxylic acid, there may be mentioned:

- homopolymers of an unsaturated carboxylic acid such as (meth)acrylic acid, crotonic acid, isocrotonic acid, maleic acid, cinnamic acid, 2-methylmaleic acid, fumaric acid, itaconic acid, 2-methylitaconic acid or α,β-methyleneglutaric acid, and

- copolymers of at least one of the aforementioned unsaturated carboxylic acids.

The polycarboxylic acid is preferably selected from citric acid, succinic acid, tartaric acid, maleic acid, itaconic acid, 1,2,3,4-butanetetracarboxylic acid and homopolymers and copolymers of maleic acid, acrylic acid and itaconic acid.

The hardener may be an anhydride, in particular maleic anhydride, succinic anhydride or phthalic anhydride.

Preferably, the binder contains as curing agent at least one non-polymeric organic polycarboxylic acid having a number average molar mass of less than or equal to 1000, preferably less than or equal to 750, and advantageously less than or equal to 500 g/mol.

The aqueous binder containing a hardener selected from polycarboxylic acids has a pH value of less than 7, preferably less than 5 or between 2 and 5.

The hardener may contain a polyol. The polyols may contain primary, secondary or tertiary alcohol functionality, or mixtures thereof.

Preferably, the binder contains, as curing agent, at least one polyol having a molar mass less than or equal to 1000, preferably less than or equal to 750, and advantageously less than or equal to 500 g/mol.

The polyol used as the hardener may be selected from aliphatic or aromatic compounds. Preferably the polyol used as the curing agent is water miscible or water soluble.

The polyol may be selected from sugars, in particular reducing sugars, non-reducing sugars, hydrogenated sugars and mixtures thereof.

The polyol may be selected from linear, cyclic or branched monosaccharides and oligosaccharides.

Preferably the polyol is selected from:

- glycerin,

- polyglycerols,

- inositol,

- hydrogenated sugars (such as erythritol, arabitol, xylitol, sorbitol, talit, mannitol, iditol, maltitol, isomaltitol, lactitol, cellobitol, palatinite, maltotriite),

- sorbitan and isosorbide,

- butanediol and propanediol,

- a hydrogenation product of a starch hydrolyzate, a hydrogenation product of a hemicellulose hydrolyzate or polyols obtained by the functionalization of vegetable oil,

- sucrose,

- reducing sugars such as glucose, fructose, maltose, lactose or isomalt,

- trimethylolpropane, pentaerythritol, neopentyl glycol.

Preferably, the hardener contains at least one polyol selected from sucrose, glucose, fructose, lactose, isomalt, isosorbide or talite, sorbitan, inositol, glycerol, erythritol, arabitol, xylitol, sorbitol, mannitol, iditol, maltitol, isomaltitol, lactitol , cellobite, palatinite, maltotriite, hydrogenation products of starch hydrolyzate, trimethylolpropane and pentaerythritol.

The polyol may also be selected from naturally occurring polyphenols. In this case, the hardener may contain a polyol selected from lignin and its derivatives, lignans, ammonium lignosulfonate or salts derived from alkali or alkaline earth metals and lignosulfonic acid, tannic acids, tannins and condensed tannins.

Ammonium lignosulfonate is a by-product resulting from the processing of wood for the manufacture of paper pulp in accordance with the "sulfite" method. The treatment of paper pulp with ammonium sulfite or ammonium bisulfite makes it possible to obtain ammonium lignosulfonates.

Ammonium lignosulfonate also makes it possible to impart good fire resistance to the binder.

Salts derived from alkali or alkaline earth metals and lignosulfonic acid are generally complex mixtures of several lignosulfonic acids in salt form, commonly known as "lignosulfonates". Lignosulfonates are by-products resulting from the processing of wood to make paper pulp in accordance with the aforementioned "sulfite" process, which uses sulfite or bisulfite. Depending on the nature of the counterion of the sulfite or bisulfite used, in particular, alkali metal or alkaline earth metal salts and lignosulfonic acid are obtained. In the present invention, preferred salts derived from alkali metals and lignosulfonic acid are sodium lignosulfonate or potassium lignosulfonate, advantageously sodium lignosulfonate, and preferred salts derived from alkaline earth metals and lignosulfonic acid are magnesium lignosulfonate or calcium lignosulfonate.

The polyol may also be selected from polyhydroxylated natural polymers such as xanthan gum, pectin, chitosan, starch or hyaluronic acid.

An aqueous binder containing a hardener selected from polyols is characterized by a pH value of:

- more than 4, preferably more than 5, or

- in the range between 4 and 12, preferably between 5 and 9.

The composition may contain, in addition to components a) and b), a catalyst and/or conventional additives.

The binder may also contain a catalyst. The function of the catalyst is to adjust the crosslinking profile. This makes it possible, for example, to increase the crosslinking speed or decrease the crosslinking temperature.

The catalyst may be selected from bases and Lewis acids. The catalyst may be organic or inorganic in nature.

Preferably the catalyst will be used when the curing agent is a polyol. In this case, the catalyst may be a basic organic compound such as an amine, an amine salt, a quaternary ammonium, or a phosphorus-containing compound.

The catalyst may be selected from imidazoles, imidazolines and mixtures thereof. By way of examples of imidazoles, there may be mentioned imidazole, 1-methylimidazole, 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole and 4,4'-methylenebis(2-ethyl-5-methylimidazole). By way of example of imidazoline, 2-ethyl-N-phenylimidazoline may be mentioned. Preferably 2-methylimidazole is used.

The catalyst may be selected from metal salts such as zinc salts.

The sum of the mass fractions of the epoxy precursor (a) and the curing agent (b) is, based on the mass of solids of the binder compound in order of increasing preference, at least 50%, at least 60%, at least 70%, at least at least 80%, at least 90%, at least 95%, (wt.) of the solids of the binder.

The binder compound contains, in order of increasing preference per mass part of hardener (b), from 0.5 to 50 parts, from 0.5 to 20 parts, from 1.0 to 15 mass parts, of the epoxy precursor (a).

The binder contains, in order of increasing preference, per 100 mass parts of epoxy precursor (a) and hardener (b) from 0.1 to 5 parts, from 0.5 to 3 parts, from 0.5 to 2 mass parts of the catalyst.

The binder may contain, relative to the weight of the epoxy precursor (a) and hardener (b):

- from 10 to 90% or from 20 to 80% or from 30 to 70% or from 40 to 60% by weight of the epoxy precursor (a) and

- from 10 to 90% or from 20 to 80% or from 30 to 70% or from 40 to 60% (wt.) hardener (b).

The binder according to the invention may also contain conventional additives. These additives below are present in the following proportions, calculated based on 100 parts by weight of epoxy precursor (a) and hardener (b):

- from 0 to 5 parts of silane,

- 0 to 40 parts, preferably 4 to 25 parts, oil or oil emulsion,

- from 0 to 5 parts of a hydrophobic agent, in particular silicone,

- from 0 to 20 parts of urea, preferably from 0 to 10, and even better from 0 to 5 parts,

- from 0 to 40 parts, preferably from 0 to 20 parts, cheapening filler.

The binder compound according to the invention may consist of water, an epoxy precursor selected from aliphatic compounds (a), a curing agent (b), optionally a catalyst and conventional additives.

The aqueous binder contains at least 40%, preferably at least 50% (w/w) of water based on the total weight of the aqueous binder.

The role of additives is known and briefly summarized. Silane is a sizing agent between the fibers and the binder, which also functions as an antioxidant. Oils are anti-dust agents and hydrophobic agents. Urea acts as a plasticizer. A cost-reducing filler is an organic or inorganic filler which is soluble or dispersible in the binder and which makes it possible, in particular, to reduce its cost.

The hydrophobic agent is preferably a reactive silicone. The term "reactive silicone" is intended to mean a polyorganosiloxane containing at least one hydroxyl (silanol), carboxyl or anhydride, amine, epoxide or vinyl functionality capable of reacting with at least one of the binder compound constituents. and/or with silanol groups on the glass surface.

The reactive silicone is preferably liquid at ambient temperature. Its average molar mass is generally less than or equal to 50,000, preferably less than or equal to 10,000. residues with a proportion preferably not exceeding 20%, in particular not more than 10%, (wt.) phenylsiloxane elementary units in relation to the mass of silicone. Said main chain contains at least one reactive hydroxyl, carboxyl or anhydride, amine, epoxide or vinyl functionality at the terminal position (at one of the free ends of the chain) or in a side group (or graft structure). Preferably, the reactive silicone contains at least two terminal functionalities, preferably hydroxyl functionalities.

Preferably, the reactive silicone contains a reactive functionality, advantageously a silanol functionality, at each end of its chain.

The reactive functionality of the reactive silicone may be a blocked protecting group that releases said reactive functionality when exposed to heat. The proportion of reactive silicone in the binder is generally in the range of 0.1 to 5 parts, preferably 0.3 to 3 parts, advantageously 0.5 to 2.5 parts, and even better 0 .7 to 1.8 mass parts, when calculated per 100 mass parts of the sum of components (a) and (b).

The preparation of the binder is carried out by simply mixing the aforementioned constituents with water.

The binder is intended to be applied to mineral fibres, in particular glass or stone fibres.

The subject of the present invention is also a method for manufacturing an insulating product. According to one embodiment, the insulation product is in the form of mineral wool. The method also includes the steps where:

- mineral fibers are formed from the composition of the molten mineral material, after that

- an aqueous binder is applied to the mineral fibers, after which

- the fibers are collected in the form of a web, after which

- the web is subjected to heat treatment at a temperature of more than 150°C, preferably in the range from 180 to 220°C, so as to obtain a binder as a result of heat curing of the non-volatile components of the binder compound.

Typically, the binder is sprayed onto the mineral fibers in a fiber collecting bin which is located downstream of the centrifugal device and up to a fiber collecting member in the form of a web of fibers, which is subsequently treated at a temperature that allows the binder to be crosslinked and shaped. hard-melting binder.

In one embodiment, the method of the present invention, therefore, includes the step of obtaining an aqueous binder compound, which includes mixing the precursor, hardener, catalyst and optional additives before carrying out the step of applying to the fibers.

The binder has a pot life of at least more than 5 minutes, preferably more than one hour, even better ranging from several hours to several days.

The binder is free from formaldehyde and/or bisphenol, in particular bisphenol A.

The binder obtained by curing the binder compound is an epoxy resin. These epoxy resins are characterized by a glass transition temperature that can range between 0 and 150°C.

Insulating products obtained using the process according to the invention from these bonded fibers are also the subject of the present invention.

The insulating products may be sound and/or thermal insulating products.

Mineral fibers are selected from glass fibers or stone fibers.

The mineral fibers and the binder are, in order of increasing preference, at least 95%, at least 98%, at least 99%, by weight, based on the weight of the insulation product.

The mineral fibers and binder may be in the form of mineral wool. In this case, the insulation products are in the form of mineral wool. In general, they take the form of a mat, cloth or felt made of mineral, glass or stone wool.

The total weight of the binder represents 0.5 to 15% of the total weight of the mineral fibers, preferably 1 to 12%, and even more preferably 2 to 6%.

The mineral fibers and the binder may be in the form of a mesh containing bound mineral fibers. In this case, the insulation products are in the form of a mesh of mineral fibres, also glass or stone fibres.

The mesh may also be designed to form a surface covering of said mat, web or felt.

Examples

The compounds used to make the binders are listed in the table below.

Connections Nature Name Predecessor Polyglycidyl Ether of Glycerol PGG Isosorbide polyglycidyl ether PGI Hardener Polyacid: citric acid CA Polyol: sucrose SU Polyol: sorbitol SO Polyol: maltitol MA Polyol: erythritol ER Polyol: trimethylolpropane TR Polyamine: tetraethylenetetraamine TETA Polyamine: cycloaliphatic polyamine DEH 2132 Amino acid: lysine LYS Catalyst Amine: 2-methylimidazole cat

Bonding compounds

Binder compounds are obtained by introducing water, a precursor, a hardener and optionally a catalyst into a container with vigorous stirring until a homogeneous solution is obtained.

The binders tested and their properties are summarized in the table below. The specified shares are expressed in mass parts.

Determination of property stability during storage or "pot life"

Binders having a solids content of 30% are stored in 250 ml glass jars at 25°C.

The storage stability of the properties is determined by evaluating the period of time after which the gel is formed.

Determination of crosslinking temperatures

A rectangle at 55 mm x 6 mm cut from an unbonded glass microfiber filter (Whatman, reference 1822-150) is impregnated with each of these binders in an amount of approximately 300 mg.

These impregnated rectangles are introduced into the dynamic mechanical analysis device and gradually increase (4°C/minute) the temperature of the sample holder, starting from 25°C up to 250°C, while continuously measuring the storage modulus (E') under three-point bending (frequency 1 Hz, strain 0.1%).

Used abbreviations

SC: composition solids level.

EP/H: weight ratio between epoxy precursor and hardener.

Cat.: % (wt.) catalyst in relation to the weight of the precursor (a) and curing agent (b).

Gel formation: "pot life", the period of time from which a gel forms.

CT: crosslinking temperature in °C.

Tg: glass transition temperature in °C as measured using DSC (differential scanning calorimetry) at a gradient of 2 °C/min.

Vis: Viscosity in Pa.s as measured using a Brookfield viscometer at 20° C. for binders having a solids content of 70%.

SC (%) EP/H Cat. % CT Tg Vis. pH Gel formation Wed pr. 1 PGI/TETA thirty 6.5/1 0 fifty 76 - - Less than 1 hour Wed pr. 2 PGI/DEH thirty 1.6/1 0 84 42.7 - 12 Less than 1 hour Wed pr. 3 PGI/LYS thirty 5.4/1 0 35 44 - 7 Less than 1 hour Wed pr. 4 PGG/TETA thirty 5.8/1 0 fifty 54 - - Less than 1 hour Wed project 5 PGG/DEH thirty 1.4/1 0 twenty 53 - eleven Less than 1 hour Etc. one PGI/CA thirty 1.4/1 0 105 90 0.12 < 3 > 1 week Etc. 2 PGI/MA/Cat thirty 4/1 one 135 65 0.04 9 > 1 day Etc. 3 PGI/SO/Cat thirty 10/1 one 125 53 0.03 9 > 1 day Etc. four PGI/SA/Cat thirty 3.6/1 one 130 58 0.04 9 > 1 day Etc. 5 PGI/ER/Cat thirty 30/1 one 125 60 - 9 > 1 day Etc. 6 PGI/TR/Cat thirty 10/1 one 125 37 - 9 > 1 day Etc. 7 PGI/TR/Cat thirty 30/1 one 125 thirty - 9 > 1 day Etc. eight PGG/CA thirty 0.9/1 0 175 96 0.12 < 3 > 1 week Etc. 9 PGG/MA thirty 1.5/1 5 95 36 0.08 9 > 1 day Etc. ten PGG/SO thirty 4.7/1 5 100 23 0.03 9 > 1 day

As shown in the Comparative Examples, epoxidized aliphatic precursors react with polyamine hardeners at temperatures of less than 90°C. Therefore, their use is incompatible with the intended applications.

Binder compounds according to the invention advantageously have a crosslinking temperature of more than 90°C or even more than 100°C and less than 200°C. These temperatures are:

— high enough to avoid any risk of premature crosslinking or gelation prior to injection, and

low enough for moderate or even low energy costs during the curing step of the binder.

This results in temperatures of less than 200° C. or even less than 150° C. and high crosslinking rates.

Binder compounds are characterized by low viscosity, regardless of the nature of the hardener.

All binder compounds containing a polyol type hardener are characterized by a pH value in the range from basic to neutral (examples 3 to 6).

insulation products

Thereafter, the binder compounds were evaluated as a binder on woven glass fiber textiles. The textiles are impregnated with the binder and crosslinked in a ventilated oven for two minutes at 215°C. As proven by these tests, the binder compositions produced are satisfactory for bonding glass fiber composites.

The tensile strengths of the thus coated woven textiles were determined before and after aging. This test consists of measuring the tensile strength of a glass mesh impregnated with a binder. The results are shown in the table below. As it turns out, the mechanical properties are sufficient. Insulating products based on mineral fibers bonded with a binder, which is the result of crosslinking the binder compounds according to the invention, are satisfactory.

Fmax before aging (n) Fmax after aging (n) Etc. 8: PGG/CA 47 40 Etc. 1: PGI/CA fifty 35 Etc. 4: PGI/SU 45 33 Etc. 3: PGI/SO 44 54

Claims (35)

1. An insulating product containing mineral fibers and a binder, the specified binder in the composition of the insulating product is obtained by curing a binder compound containing as components: a) compounds containing at least one epoxy functionality, including at least one epoxy precursor selected from aliphatic compounds containing at least two epoxy functionality, while aliphatic compounds containing at least two epoxy functionality represent at least 50% of the total mass of compounds containing at least one epoxy functionality of the binder compound, b) a curing agent selected from compounds containing at least two reactive functionalities selected from hydroxyl and carboxylic functionalities, it being possible for the carboxylic acid functionality to be in the form of a salt or an anhydride. 2. Insulating product according to claim 1, characterized in that the mineral fibers are selected from glass fibers or stone fibers. 3. Insulating product according to claim 1 or 2, characterized in that the mineral fibers and the binder represent at least 95% (wt.) of the weight of the insulating product. 4. Insulating product according to any one of paragraphs. 1-3, characterized in that the mineral fibers and the binder are in the form of mineral wool. 5. Insulating product according to any one of paragraphs. 1-3, characterized in that the total mass of the binder is from 0.5 to 15% of the total mass of mineral fibers, preferably from 1 to 12%, and even better from 2 to 6%. 6. An insulating product according to any one of the preceding claims, characterized in that the aliphatic compound containing at least two epoxy functionalities is selected from: - polyglycidyl ether of an aliphatic polyol, - an aliphatic polyepoxy compound obtained by oxidation of a compound containing at least two double bonds. 7. An insulating product according to the preceding claim, characterized in that the polyglycidyl ether of the aliphatic polyol is selected from: - glycerol polyglycidyl ether, polyglycerol polyglycidyl ether, inositol polyglycidyl ether, erythritol polyglycidyl ether, arabitol polyglycidyl ether, xylitol polyglycidyl ether, tallit polyglycidyl ether, sorbitan polyglycidyl ether, mannitol polyglycidyl ether, polyglycidyl ether , maltitol polyglycidyl ether, isomaltitol polyglycidyl ether, lactitol polyglycidyl ether, cellobitol polyglycidyl ether, palatinite polyglycidyl ether, maltotriite polyglycidyl ether, isosorbide polyglycidyl ether, sorbitan polyglycidyl ether, butanediol polyglycidyl ether, polyglycidyl ether butanediol, polyglycidyl ether , sucrose polyglycidyl ether, glucose polyglycidyl ether, fructose polyglycidyl ether s, maltose polyglycidyl ether, lactose polyglycidyl ether, isomalt polyglycidyl ether, trimethylol propane polyglycidyl ether, pentaerythritol polyglycidyl ether and neopentyl glycol polyglycidyl ether, - polyglycidyl ether polyol obtained by functionalization of vegetable oil, and - polyglycidyl ether of starch hydrolyzate hydrogenation products or hemicellulose hydrolyzate hydrogenation products. 8. An insulating product according to claim 6, characterized in that the aliphatic polyepoxy compound obtained by oxidizing a double bond is obtained by oxidizing a compound selected from furan, terpene or unsaturated vegetable oil. 9. Insulating product according to any one of the preceding claims, characterized in that the curing agent contains at least one polycarboxylic acid or a salt or anhydride of such an acid. 10. Insulating product according to the preceding claim, characterized in that the polycarboxylic acid is selected from citric acid, succinic acid, tartaric acid, maleic acid, itaconic acid, 1,2,3,4-butanetetracarboxylic acid and homopolymers and copolymers of maleic acid, acrylic acid and itaconic acid. 11. Insulating product according to any one of the preceding claims, characterized in that the hardener contains at least one polyol selected from sucrose, glucose, fructose, lactose, isomalt, isosorbide or thalit, sorbitan, inositol, glycerol, erythritol, arabitol, xylitol , sorbitol, mannitol, iditol, maltitol, isomaltitol, lactitol, cellobite, palatinite, maltotriite, hydrogenation products of starch hydrolyzate or hydrogenation products of hemicellulose hydrolyzate, trimethylol propane and pentaerythritol. 12. Insulating product according to one of the preceding claims, characterized in that the hardener contains at least one polyol selected from lignin and its derivatives, lignans, ammonium lignosulfate or salts derived from alkali or alkaline earth metals and lignosulfonic acid, tannic acids, tannins and condensed tannins. 13. Insulating product according to any one of the preceding claims, characterized in that the composition also contains a catalyst and/or conventional additives. 14. Insulating product according to any one of the preceding paragraphs, characterized in that the sum of the mass fractions of the epoxy precursor (a) and hardener (b) is at least 50 wt. -%, preferably at least 95 wt. from the solids of the binder compound. 15. An insulating product according to any one of the preceding claims, characterized in that the bonding compound contains from 0.5 to 50 parts by weight of epoxy precursor (a) per part by weight of hardener (b). 16. Aqueous binder for insulating products based on mineral fibers, containing as components other than water: a) compounds containing at least one epoxy functionality, including at least one epoxy precursor selected from aliphatic compounds containing at least two epoxy functionality, while aliphatic compounds containing at least two epoxy functionality represent at least 50% of the total mass of compounds containing at least one epoxy functionality of the binder compound, b) a curing agent selected from compounds containing at least two reactive functionalities selected from hydroxyl and carboxylic functionalities, it being possible for the carboxylic acid functionality to be in the form of a salt or an anhydride. 17. An aqueous binder compound according to the preceding claim, characterized in that the epoxy precursor is water-soluble or miscible with water. 18. Water binder connection according to any one of paragraphs. 16 and 17, characterized in that the components (a) and (b) are characterized by a crosslinking temperature, as determined using dynamic mechanical analysis at a heating rate of 4°C/min, greater than or equal to 90°C. 19. A method for manufacturing an insulating product containing mineral fibers and a binder, where: - an aqueous binder compound according to any one of paragraphs. 16-18 applied to mineral fibers, - the binder is obtained as a result of thermal curing of the non-volatile components of the binder compound. 20. A method of manufacturing an insulating product according to any one of paragraphs. 1-15, characterized in that the insulating product is in the form of mineral wool, while the method also includes stages, where: - mineral fibers are formed from the composition of the molten mineral material, after that - an aqueous binder is applied to the mineral fibers, after which - the fibers are collected in the form of a web, after which - the web is subjected to heat treatment at a temperature of more than 150°C, preferably in the range from 180 to 220°C, so as to obtain a binder as a result of heat curing of the non-volatile components of the binder compound.

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