EP4172126A1

EP4172126A1 - Aromatic polyol-stabilized resol resin

Info

Publication number: EP4172126A1
Application number: EP21745371.1A
Authority: EP
Inventors: Aurélie LEGRAND; Edouard Obert
Original assignee: Saint Gobain Isover SA France
Current assignee: Saint Gobain Isover SA France
Priority date: 2020-06-29
Filing date: 2021-06-29
Publication date: 2023-05-03
Also published as: CO2022018901A2; BR112022026726A2; WO2022003289A1; KR20230029879A; FR3111900B1; CA3181460A1; US20230340180A1; FR3111900A1; JP2023532739A

Abstract

The invention relates to a stabilized resol resin comprising water, a water-soluble amino phenol resin and a water-soluble aromatic polyol, as a solubilizer for the water-soluble amino phenol resin. The invention also relates to a diluted aqueous binder composition containing such a stabilized resol resin and additives, and to a method for producing a fibrous insulation product using such an aqueous binder composition.

Description

DESCRIPTION

Title: Resin resin stabilized by an aromatic polyol

The present invention relates to an amino resol resin, stabilized by a solubilizing agent chosen from water-soluble aromatic polyols, an aqueous binder composition prepared from this resin, a process for manufacturing an insulation product based on fibers, in in particular based on mineral wool, using this aqueous binder composition, as well as a thermal and / or acoustic insulating product obtained by this manufacturing process. The use of a water-soluble polyhydroxy aromatic compound as a resin solubilizer, or cosolvent, allows partial or complete replacement of the urea commonly used in this type of resin.

The manufacture of mineral wool-based insulation products generally includes a step of manufacturing glass or rock fibers by a centrifugation (fiberizing) process. On their path between the centrifuge device and the fiber collection belt, the still hot fibers are sprayed with an aqueous binder composition, also called a sizing composition, which then undergoes a thermosetting reaction at temperatures of about 200 ° C.

Aqueous binder compositions are prepared shortly before use by diluting a concentrated thermosetting resin with water and adding various commonly used additives (coupling agents, anti-dust additives, hydrophobic agents, catalysts).

Concentrated thermosetting resins must be stable on storage, i.e. they must not precipitate and must retain their ability to be diluted with water for as long as possible when preparing the sizing composition. . It is generally considered that a concentrated thermosetting resin is stable when, after a storage period of at least 14 days at a temperature between 12 and 18 ° C, it is still in the state of solution free from precipitate and retains a solid state. dilutability of at least 1000% (the addition of 9 volumes of water to 1 volume of resin gives a clear solution, free of permanent haze). In addition, from a regulatory point of view, it is necessary that the resin be considered non-polluting, that is to say that it contains and that it generates during its use as few compounds as possible that could be harmful. human health or the environment. The most commonly used thermosetting resins are phenolic resins belonging to the family of resols. In the technical field of phenol-formaldehyde resins, there are mainly two families, namely:

- novolac resins prepared in an acidic medium and - resols obtained by basic catalysis.

The phenolic resins of the present invention belong to this second family.

Resol resins are obtained in a basic medium by reacting phenol with an excess of formaldehyde, the formaldehyde / phenol molar ratio typically being between 2 and 4, each molecule of phenol potentially being able to react with three molecules of formaldehyde.

The resol resins thus obtained contain numerous methylol functions carried by an aromatic nucleus, which constitute the sites of crosslinking by dehydration / release of formalin. These resins consist essentially of phenol / formaldehyde (PF) condensate, residual phenol and residual formaldehyde. In an acidic medium they react, that is to say polymerize, very quickly at room temperature and precipitate. To reduce the amount of residual formaldehyde and improve the stability of the resins on storage, it has been proposed first to add to the resin, after neutralization of the catalyst, a sufficient amount of urea which reacts with the residual free formaldehyde to form urea-formaldehyde (UF) condensates. Such a resin therefore contains phenol-formaldehyde (PF) and urea-formaldehyde (UF) condensates. However, it turned out that these resins released formaldehyde at the time of the crosslinking step by thermal degradation of the urea-formaldehyde condensates. Formaldehyde was also released from the final product, when used as thermal and / or acoustic insulation. Such resols treated with urea and their preparation are described in detail in international application WO01 / 96254.

A few years ago, the Applicant proposed improved resol resins, referred to hereinafter interchangeably as “amino resols” or “amino phenolic resins”, stable on storage and essentially free from urea-formaldehyde (UF) condensates.

These amino phenolic resins are water-soluble resins which are stable at acidic pH, even at a very acidic pH of between 1 and 2. This good stability is obtained thanks to an additional reaction step which consists in reacting the resols consisting essentially of phenol / formaldehyde condensates, phenol and formaldehyde with an amine, preferably a monoalkanolamine, and in particular monoethanolamine.

This alkanolamine reacts according to the Mannich reaction with phenol / formaldehyde (PF) condensates and with residual phenol and formaldehyde to form phenol / formaldehyde / amine (PFA) condensates. At the end of the reaction, the reaction mixture can be acidified without causing polymerization at room temperature. These amino resols are therefore considered to be stable in an acidic medium. Their synthesis is described in applications WO2008 / 043960 and WO2008 / 043961 by the Applicant. They are also distinguished by the fact that they are free from urea-formaldehyde condensates. As explained previously, these undesirable UF condensates are present in large amounts in many phenolic resins of the state of the art and exhibit insufficient thermal stability, releasing formaldehyde by thermal decomposition.

In known manner, up to 25% by weight, preferably between 10% and 20% by weight of urea, can be added to the amino phenolic resin, after reaction with monoalkanolamine, cooling the reaction mixture and acidification, up to 25% by weight, preferably between 10% and 20% by weight, of urea, these amounts being expressed relative to the total dry weight of the amino resole. Urea is then used mainly as a cosolvent or solubilizing agent and further reduces the cost of sizing compositions and products obtained. Urea also traps traces of formaldehyde which may still be present at the end of the synthesis (less than 0.2%).

Amino phenolic resins, in aqueous solution stabilized with urea (solubilizing agent), have thus been used for more than ten years by the Applicant for the manufacture of insulation products based on mineral fibers which release very low amounts of formaldehyde during production and during use.

The only drawback of these resins is that ammonia (Nhb), a thermal degradation product of urea, is formed during the thermal curing step at the production site and also, to a lesser extent. , in use.

The aim of the present invention has been to provide a solubilizing agent, or cosolvent, different from urea, which

- is capable of stabilizing an aqueous solution of amino phenol-formaldehyde resin at least as effectively as urea (absence of crystals and dilutability greater than 1000% for at least 14 days),

- does not release ammonia or other harmful substances when subjected to the curing temperatures of resole resins, typically between 180 and 230 ° C, and

- is preferably not classified as a chemical agent which is carcinogenic, mutagenic or toxic to reproduction (CMR).

The Applicant has tested a large number of organic compounds, in particular amino acids, (poly) aldehydes, aromatic and non-aromatic polyols and carbohydrates, but only water-soluble aromatic polyols have proved to be sufficiently effective to stabilize amino phenolic resins. concentrated solution in water for at least 14 days.

The inventors have observed that certain polyhydroxylated aromatic compounds were even more effective stabilizing agents than urea, which makes it possible to use less and advantageously compensate for at least partly the higher cost of these compounds compared to that of urea.

The present invention therefore relates to a stabilized resol resin comprising

(a) water,

(b) a water-soluble amino phenolic resin, preferably consisting essentially of phenol-formaldehyde (PF) condensate and phenol-formaldehyde-amine (PFA) condensate, and

(c) a water-soluble aromatic polyol, as a solubilizing agent for the water-soluble amino phenolic resin.

It also relates to an aqueous binder composition, prepared from the resol resin stabilized by dilution and addition of current additives. This aqueous binder composition therefore comprises water (of dilution), the stabilized resol resin defined above, and one or more additives chosen from coupling agents, anti-dust oils or emulsions, hydrophobic agents and hardening reaction accelerators.

Finally, a subject of the invention is a process for manufacturing an insulating product based on organic or mineral fibers using the aqueous binder composition, as well as an insulating product obtained by this process, in which the organic or mineral fibers are bonded. between them by an insoluble and infusible binder obtained by curing the ingredients of the aqueous binder composition.

Throughout the description of the present invention, it should be distinguished between

- amino phenolic resin, obtained by condensation of phenol, formaldehyde and amine in a basic medium and which is free from urea-formaldehyde (UF) condensate,

- the stabilized resol resin which contains the amino phenolic resin, water, and the solubilizing agent, and the binder composition prepared by diluting the stabilized resol resin and adding known additives such as coupling agents, anti -dust, hydrophobic agents and catalysts or accelerators. The stabilized resol resin is therefore the concentrated resin, resulting from the synthesis, which will be stored, transported, marketed and used as a thermosetting component for the preparation of the aqueous binder composition, shortly before the implementation of the process of manufacturing.

It advantageously contains

- from 75 to 99% by weight, preferably from 80 to 97% by weight, in particular from 85 to 95% by weight, of water-soluble amino phenolic resin, and

- From 1 to 25% by weight, preferably from 3 to 20% by weight, in particular 5 to 15% by weight of a water-soluble aromatic polyol, these percentages being relative to the total dry weight of the stabilized resole resin.

Its water content is generally between 30 and 60%, preferably between 35 and 55% by weight and in particular between 40 and 50% by weight.

The term "a water soluble aromatic polyol" used to describe the solubilizer includes both pure compounds, used alone, and mixtures of two or more water soluble aromatic polyols.

The resin also contains small amounts of salt resulting from the neutralization of the catalyst (strong base such as NaOH or KOH) by an acid, for example sulfamic acid, at the end of the synthesis of the resin.

The adjective "stabilized" relating to the resole resin means in the present invention that the resin remains for at least 14 days of storage at a temperature of 12 to 18 ° C in the form of a clear solution, free of precipitate, and that it retains during this period a dilutability in water of at least 1000%.

The solubilizing agent used in the present invention to at least partially replace urea, used hitherto, is chosen from water-soluble aromatic polyols which are preferably not part of the chemical compounds carcinogenic, mutagenic or toxic for reproduction (CMR ). The list of CMR chemical compounds is that which appears in appendix VI of Regulation EC No 1272/2008.

It is considered in the present application that the aromatic polyols water-soluble are those having a solubility in water at 20 ° C greater than 20 g / L, preferably greater than 50 g / L.

Aromatic character is an important aspect of the solubilizing agents used in the present invention. The Applicant has in fact tested a certain number of non-aromatic polyhydroxy compounds such as glycerol, carbohydrates and hydrogenated sugars (alditols) which are well soluble in water and not classified as CMR, but are ineffective in stabilizing the resin. phenolic, that is to say to preserve the dilutability of the resin for at least 14 days of storage at a temperature of 12 - 18 ° C and to prevent its crystallization when stored at low temperature (3 ° C). It is probable that the aromatic character of polyols increases their affinity for the phenolic resin, itself aromatic, and thus increases the solubility of the latter in water.

The solubilizing agents used in the present invention have at least two hydroxyl groups. The hydroxyl groups are preferably located directly on the aromatic ring. The solubilizing agent may have a monocyclic (benzene) or polycyclic (naphthalene, anthracene) aromatic ring. It is advantageously monocyclic or bicyclic, preferably monocyclic, and carries at least two, preferably two or three hydroxyl functions, located directly on the aromatic nucleus.

Mention may be made, as examples of polyhydroxylated aromatic compounds which can be used as solubilizing agent in the present invention, unsubstituted polyphenols such as resorcinol, phloroglucinol and pyrocathecol, substituted polyphenols bearing aldehyde, carboxylic acid or alkyl substituents. and ether, such as gallic acid, 3,4-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,4-dihydroxybenzaldehyde, 2-hydroxy-3-methoxybenzaldehyde, 4-methoxybenzene-1 , 2-diol, 4-methoxybenzene-1, 3-diol and mixtures thereof.

Of these resorcinol and phloroglucinol are particularly preferred. Indeed, these compounds are able both to dissolve the amino phenolic resin in water and to trap the traces of free formaldehyde (less than 0.2%) which could be present in the amino phenolic resin at the end of the process. synthesis. In a known manner, resorcinol and phloroglucinol are indeed capable of reacting with formaldehyde and of forming aromatic compounds with methylol function (s) capable of reacting with the PF and PFA condensates of the phenolic resin.

When the water-soluble aromatic polyol (s) used are capable of reacting with formaldehyde, the addition of urea to the resol resin is in principle superfluous and the stabilized resol resin of this present invention. The invention is then preferably urea-free. The total absence of urea guarantees the absence of ammonia emanations (NFb) during the thermal curing stage of the binder and during the use of the insulation product produced.

When using a solubilizing agent which, unlike resorcinol, is not able to trap traces of formaldehyde, it may be useful to add a small amount of urea to the resol resin to stabilize it. This addition can be done before or after the addition of the polyhydroxylated aromatic solubilizing agent, but must be done after the end of the synthesis of the amino phenolic resin consisting essentially of PF and PFA condensates, that is to say after cooling and neutralization of the reaction solution. In fact, the formation of urea-formaldehyde condensate should be avoided during resin synthesis.

Although, thanks to the present invention, it is technically possible to dispense with urea entirely, the addition of the latter to the resol resin is often advantageous from an economic point of view.

When both urea and a water-soluble aromatic polyol are used as the solubilizing agent, the resin preferably contains less than 15% by weight, for example 0.1 to 15% by weight, preferably less than 15% by weight. 10% by weight, for example 0.5 to 10% by weight, in particular less than 5% by weight, for example 1 to 5% by weight of urea, based on the total dry weight of the stabilized resole resin (resin amino phenolic + aromatic polyol + urea).

The urea / aromatic polyol weight ratio is then generally between 1/4 and 3/1, preferably between 1/3 and 2/1, in particular between 1/2 and 1.

The phenolic resin used in the present invention contains basic (protonable) amine functions and is stable in an acidic medium.

These phenolic resins with amine functions are known and their preparation is described in detail in applications WO2008 / 043960 and WO2008 / 043961 by the Applicant. They are essentially made up of of phenol / formaldehyde (PF) and phenol / formaldehyde / amine (PFA) condensates and are distinguished in particular by the absence of urea-formaldehyde (UF) condensates. As explained in the introduction, these urea-formaldehyde condensates are present in large amounts in many other phenolic resins of the state of the art and have insufficient thermal stability, releasing formaldehyde and ammonia by thermal decomposition.

The stabilized resol resin of the present invention advantageously has a pH of between 1.0 and 6.5, preferably between 1.5 and

5.5, more preferably between 1, 6 and 5.0.

The aqueous binder compositions prepared by diluting the stabilized resol resin with water generally exhibit a less acidic pH than the resol resins, typically between 3 and 7, in particular between 3.5 and

6.5, which is advantageous for preventing corrosion of insulation product manufacturing facilities. The dilution water used for the preparation of the binder compositions from the stabilized resol resin may come in part from the wash water recycled from the insulation product manufacturing facilities.

The binder composition of the present application therefore contains water, a stabilized resol resin and one or more additives, commonly used in the field of insulation products based on mineral wool.

These additives are chosen among others from coupling agents, in particular functional silanes such as aminosilanes or epoxysilanes, anti-dust oils or oil emulsions, in particular mineral oils, hydrophobic agents such as polyorganosiloxanes (silicones) reactive or not, and the accelerators of the curing reaction.

At the time of application to the fibers, the binder composition preferably has a dry matter content of between 2 and 25% by weight, preferably between 3 and 15% by weight. It therefore contains 75 to 98% by weight, in particular 85 to 97% by weight of water.

In a preferred embodiment, the aqueous binder composition is urea free.

The binder composition is applied in an amount such that the content of insoluble and infusible binder in the final product obtained after curing thermal, or between 2% and 20% by weight, preferably between 3% and 15% by weight, in particular between 4 and 12% by weight.

A subject of the present invention is also a process for manufacturing an insulating product based on mineral or organic fibers. This process comprises the following successive steps

- the application of an aqueous binder composition according to the invention on mineral or organic fibers, preferably mineral fibers, and

- Heating the fibers sized with the aqueous binder composition so as to evaporate the volatile phase of the aqueous binder composition and to achieve thermal hardening of the non-volatile residue, or the packaging of the mineral or organic fibers sized with the aqueous composition of unhardened binder for storage and / or transport.

The mineral fibers are advantageously chosen from fibers of mineral wool, in particular of glass or rock wool.

When the insulation product is a mineral wool-based product, the binder composition is sprayed onto the mineral fibers at the outlet of the centrifugation device (fiberizing) and before the mineral fibers are collected on the receiving organ ( forming) in the form of a web of fibers which is then treated in an oven at a temperature allowing the crosslinking of reactive ingredients and the formation of an infusible binder (baking). This crosslinking / thermal curing step is carried out by heating to a temperature greater than or equal to 180 ° C, preferably between 190 ° C and 220 ° C, for a period of between 20 seconds and 300 seconds, preferably between 30 and 250 seconds.

When the insulation product is a product based on organic fibers, such as fibers of plant origin, for example cellulosic fibers, or of animal origin, for example wool, the firing temperature is generally lower than that used for cooking products based on mineral fibers in order to preserve the organic fibers from possible thermal degradation. The cooking temperatures are, for example, between 150 and 200 ° C. The cooking time is usually between several minutes and several tens of minutes, for example between 5 and 50 minutes, preferably between 10 and 30 minutes.

In the process of the present invention, the baking of the inorganic or organic fibers can be done immediately after application of the binder composition to the fibers and collection of the sized fibers on a conveyor belt, for example by passing through a thermostatically controlled oven at the temperature of desired cooking.

The process of the present application also covers an embodiment where the mat of sized fibers is not cured immediately but is packaged, for example partially dried, cut, compressed, shaped and packaged, with a view to a step of separate baking of the manufacturing step of the bonded fiber mat.

The packaging material must be chosen so as to allow the storage and / or transport of these intermediate products (fibers sized with an unhardened binder) for an additional process step, implemented subsequently or in a different location, and comprising the thermal hardening of the binder, optionally after forming of the intermediate product, for example in a mold.

The packaging material is preferably a plastic film.

Examples

Synthesis of unstabilized resol resin

380 g of phenol (4 moles), 313 g of paraformaldehyde, used as a source of formaldehyde (10 moles), are introduced into a 2-liter reactor surmounted by a condenser and equipped with a stirring system, and 367 g of water (paraformaldehyde / phenol molar ratio equal to 2.5) and the mixture is heated to 45 ° C. with stirring.

53.2 g of a 50% sodium hydroxide solution (i.e. 7% by weight relative to the phenol) are then added regularly over a period of 30 minutes, then the temperature is gradually raised to 70 ° C. over 30 minutes and the maintains it for 80 minutes.

Then, the temperature is gradually reduced over a period of 30 minutes to 60 ° C. while simultaneously adding to the reaction mixture, in a regular manner, 71.5 g of monoethanolamine (1.17 moles). The temperature is maintained at 60 ° C for 15 minutes, the mixture is cooled to 35 ° C about 30 minutes and solid sulfamic acid is added over 60 minutes until the pH is 5.0. Sulfamic acid in 15% solution is then used to lower the pH to 4.5. If necessary, the solids content of the liquid resin by weight is adjusted to 58% with water.

The resin obtained has the appearance of a clear aqueous composition: it has a free formaldehyde level equal to 0.1%, a free phenol level equal to 0.5% (these levels being expressed relative to the total weight of liquid) and a dilutability greater than 2000%. It is called unstabilized resol resin.

Preparation of stabilized resole resins

The unstabilized resol resin is divided into several batches and a stabilizing agent to be tested is added to each batch in an amount equal to 20 parts per 80 parts of dry weight of resin, for those of sufficient solubility, and in an equal amount. at 10 parts by weight per 80 parts by dry weight of unstabilized resole resin for those with insufficient solubility (see Table 1). Stirred at room temperature until complete dissolution to obtain so-called "stabilized" resol resins, the stability of which is to be evaluated.

Two batches of stabilized resol resin are also prepared by adding, under the same conditions, respectively 5 parts of resorcinol and 5 parts of phloroglucinol to 80 parts of unstabilized resol resin.

Dilutability

The dilutability over time of the various resol resins prepared is evaluated as follows: 10 ml of the resin are poured into a 250 ml Erlenmeyer flask. Add 10 mL of water, stir and check whether a cloudiness appears or not. When the solution remains clear, another 10 ml of water is added, the mixture is stirred and the clarity of the solution is re-evaluated. This cycle is repeated until a permanent cloudiness appears (dilutability = (number of additions + 1) x 100) or when 10 mL of water has been added 19 times without the appearance of cloudiness. In the latter case, the resin has a dilutability of 2000% and is considered to be infinitely dilutable.

Stability to crystallization

To evaluate the crystallization stability of the resole resins, 20 ml of resin are poured into a glass pill jar and stored at 3 ° C., checking at regular intervals for the appearance or absence of crystals. Stability at crystallization is defined as the number of days of storage at 3 ° C without the appearance of white crystals on the bottom of the pillbox.

Free formaldehyde level

The level of free formaldehyde in resol resins is also evaluated in order to verify the ability of the stabilizing agent to react with residual formalin (function of formaldehyde scavenging agent).

For this, approximately 1 g of resole resin is taken in a 100 mL volumetric flask, and the mass m taken is precisely noted. Make up with distilled water to the mark. The level of formalin is determined using a LANGE DR6000 colorimeter fitted with an LCK 325 formalin quantification kit, following the supplier's recommendations.

The measurement is carried out on 1 mL of the sample taken from the preparation flask. The result A obtained by the colorimeter is given in mg / L. The rate of free formaldehyde is calculated as follows:

% free formaldehyde = (A x 0.1) / m x 100

The level of free formaldehyde is given as a% of the sample, expressed at ± 0.01%. Any result less than 0.01% is noted <0.01%.

Ammonia emissions

Finally, the ammonia emissions from the firing of the various resol resins are evaluated by carrying out pollution simulations in the laboratory. A resol resin solution corresponding to 1 g of dry matter, diluted beforehand to a dry matter content of 30%, is introduced into a flat-bottom glass flask with a capacity of 1 L. The inlet of a plunger is plugged into the flat-bottomed flask so as to sweep the surface of the sample at an air flow rate of 1 L / min. The whole is placed in a ventilated oven preheated to 215 ° C. The outlet of the plunger is connected to three bubblers arranged in series outside the oven each containing 100 mL of a 0.02 N sulfuric acid solution. After cooking for one hour, the contents of the bubblers are analyzed by ion chromatography to quantify the amount of ammonia trapped.

The results of the measurements are collated in Table 1 below for all of the substances tested as stabilizing agent, potential candidates for the replacement of urea.

[Table 1]

Of all the organic compounds evaluated, only resorcinol and phloroglucinol have a stabilizing power of the resol resin at least equal to or even greater than that of urea: dilutability greater than 1000% and stabilization on crystallization over an equivalent period. or longer are indeed observed.

Resorcinol and phloroglucinol are also capable, like urea, of reacting with the free formaldehyde contained in the unstabilized resole resin. When we compare resorcinol and phloroglucinol to urea, we see that ammonia emissions are greatly reduced (from 310 mg / m ³ to less than 20 mg / m ³ ).

Claims

1. Stabilized resol resin comprising

- some water,

- a water-soluble amino phenolic resin and - a water-soluble aromatic polyol, as a solubilizing agent for the water-soluble amino phenolic resin.

2. stabilized resol resin according to claim 1, characterized in that it contains

- from 75 to 99% by weight, preferably from 80 to 97% by weight, in particular from 85 to 95% by weight, of water-soluble amino phenolic resin,

- From 1 to 25% by weight, preferably from 3 to 20% by weight, in particular from 5 to 15% by weight of a water-soluble aromatic polyol, these percentages being relative to the total dry weight of the stabilized resol resin.

3. stabilized resol resin, according to claim 1 or 2, characterized in that the water-soluble aromatic polyol is a compound comprising a monocyclic or bicyclic aromatic ring, preferably monocyclic, bearing at least two hydroxyl functions located directly on the aromatic ring. 4. Resol stabilized resin according to claim 3, characterized in that the water-soluble aromatic polyol is chosen from the group consisting of resorcinol, phloroglucinol, pyrocathecol, gallic acid, 3,4-dihydroxy-benzoic acid, 2,4-dihydroxybenzoic acid , 2,4-dihydroxybenzaldehyde, 2-hydroxy-3-methoxybenzaldehyde, 4-methoxybenzene-1, 2-diol,

4-methoxy-benzene-1, 3-diol and mixtures of these compounds.

5. stabilized resol resin according to claim 4, characterized in that the water-soluble aromatic polyol is chosen from the group formed by resorcinol and phloroglucinol.

6. Resol stabilized resin according to one of the preceding claims, characterized in that it further contains from 0.1 to 15% by weight, preferably from 0.5 to 10% by weight, in particular from 1 to 5% by weight of urea, based on the total dry weight of the stabilized resol resin.

7. Resol stabilized resin according to any one of claims 1 to 5, characterized in that it is free of urea.

8. Resol stabilized resin according to any one of the preceding claims, characterized in that the water-soluble amino phenolic resin consists essentially of phenol-formaldehyde condensate and of phenol-formaldehyde-amine condensate.

9. Resol stabilized resin according to any one of the preceding claims, characterized in that it has a pH between 1, 0 and 6.5, preferably between 1, 5 and 5.5, more preferably between 1, 6 and 5.0.

10. Aqueous binder composition comprising water, a stabilized resole resin according to any one of the preceding claims and one or more additives chosen from coupling agents, anti-dust oils or emulsions, hydrophobic agents and accelerators. of the curing reaction.

11. Aqueous binder composition according to claim 10, characterized in that it contains 75 to 98% by weight of water.

12. Aqueous binder composition according to claim 10 or 11, characterized in that it is free of urea.

13. A method of manufacturing an insulating product based on mineral or organic fibers, comprising

- the application of an aqueous binder composition according to any one of claims 10 - 12 on mineral or organic fibers, preferably mineral fibers, and

14. The method of claim 13, characterized in that the mineral fibers are chosen from mineral wool fibers, in particular glass wool or rock wool.

15. Insulating product based on organic or mineral fibers, obtained by the process according to any one of claims 13 and 14.