RU2773280C1 - Long-term improvement of heat insulation values in rigid insulating foams containing polyisocyanurate/polyurethane - Google Patents

Abstract

FIELD: insulation.

SUBSTANCE: invention relates to a stabilised aged polyisocyanurate-containing insulating foam, a method for production and application thereof for heat insulation and/or in insulation panels. Stabilised aged polyisocyanurate-containing insulating foam is produced at an above 180 isocyanate index and/or stabilised aged polyurethane-containing insulating foam is produced at an isocyanate index in the range of 123 to 180. The foam contains at least one physical foaming agent with a gas lambda coefficient ≤ 12 MW/m*K at 10°C, at least one CO₂-absorbing compound and/or products of reaction between a CO₂-absorbing compound and CO₂, a sealing agent impermeable to gas diffusion, covering at least 50% of surfaces of the foam. The mol.% value of CO₂ in the stabilised aged foam is in the range between 0 and 33% as calculated for the total amount of moles of CO₂ and physical foaming agents in the stabilised aged foam. The amount of residual CO₂-absorbing compound in the stabilised aged foam is in the range between 0 and 10 wt.% as calculated for the total weight of the stabilised aged foam.

EFFECT: resulting insulating foams have improved heat insulation and retain excellent heat insulation properties for extended periods of time.

18 cl, 6 dwg, 12 tbl, 3 ex

Description

FIELD OF TECHNOLOGY TO WHICH THE INVENTION RELATES

The present invention relates to (semi)rigid containing polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foams, characterized by significantly improved long-term thermal insulation values when used under conditions of impermeability to diffusion so that over an average economically reasonable life of the foam is achieved low thermal conductivity (lambda coefficient).

In addition, the present invention relates to a method for producing said insulating foams containing polyisocyanurate (PIR) and/or polyurethane (PUR) and the use of blowing agents characterized by small lambda coefficients for gas (≤ 12 mW/m.K at 10°C), in combination with a predetermined amount of CO ₂ scavengers/sinks.

BACKGROUND OF THE INVENTION

As is well known, once manufactured, closed cell rigid insulating foams containing polyisocyanurate (PIR) and polyurethane (PUR) generally contain CO ₂ where this compound is released during foaming.

Since the thermal conductivity (when expressed in mW/m.K and denoted by the coefficient "lambda" or "λ") of CO ₂ in gaseous state is greater than the thermal conductivity of commonly used physical blowing agents, the combined lambda coefficient for a given foam containing PUR and PIR polymers, is usually greater than the corresponding value for the case of the absence of CO ₂ in the gaseous state.

To solve this problem, CO ₂ could be removed from the gas mixture of the cell after foam production, for example by using CO ₂ scavengers included in the foam.

For isocyanate-based foams (EP 1 031 601 and EP 0 618 253) a wide range of CO ₂ scavengers has previously been identified and successfully used, such as, for example, zeolites, calcium hydroxide, sodium hydroxide, lithium hydroxide, ...

US 5,649,430 discloses a process for producing low thermal conductivity insulating foam which includes foaming the resin using a gas mixture containing carbon dioxide (reaction between water and isocyanate to produce carbon dioxide which acts as a blowing agent) and sealing said foam in a gas-tight envelope using at least one gas having a thermal conductivity lower than that of carbon dioxide, at least one solid alkaline getter capable of removing carbon dioxide, and at least one desiccant. The molar ratios between "getter" and theoretical carbon dioxide as interpreted in US 5,649,430 and between desiccant and theoretical water formed should be in the range corresponding to about 1-3:1, and preferably about 1.1-2.0:1 .

EP 1031601 discloses a foamed insulating material containing an alkali metal carbonate or an alkaline earth metal carbonate obtained by reacting an alkali metal hydroxide or an alkaline earth metal hydroxide and carbon dioxide, and a water adsorbent containing a moistened water absorbent coated with a resin coating film. EP'601 discloses examples obtained using an isocyanate index of less than 100.

On the other hand, the criteria for thermal insulation foams, especially for use in building and consumer products, are becoming more and more stringent, and there is a need to further improve (i.e., reduce) the lambda (thermal conductivity) coefficient for foams containing polymers PUR and PIR, and maintaining a low lambda coefficient throughout the life of the foam.

To further improve the lambda coefficient for foams containing PUR and PIR polymers, alternative blowing agents with very low thermal conductivity, such as hydrofluorocarbons (HFCs), have been implemented. More recently, hydrofluoroolefins (HFOs) and hydrochlorofluoroolefins (HCFOs) have also been embodied.

However, there is a problem of both achieving removal of gaseous CO ₂ in an insulating foam containing PUR or PIR polymers and a significant improvement in the lambda coefficient, thereby avoiding overdosing and/or adverse effects of a residual scavenger/scavenger, as well as in the production of foams containing PUR or PIR polymers, which are characterized by very low thermal conductivity, which also remains low over long periods of time (at least over the average economic life of the foam).

PURPOSE OF THE INVENTION

The aim of the invention is to significantly improve the thermal insulation of insulating foams containing polyisocyanurate (PIR) and/or polyurethane (PUR) and maintain excellent thermal insulation properties (ie, small lambda coefficients) over extended periods of time.

The achievement of the object of the invention is achieved by combining the following steps/preliminaries:

capturing the CO ₂ compound released during foaming and during aging, in combination with

the use and presence of blowing agents with low thermal conductivity, and

coating the foam with a sealant that prevents air from being entrapped between the foam and the environment and that covers at least 50% of the surface of the foam.

Therefore, the present invention relates to novel polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foams having improved insulation values maintained over the average economic life of the foam, a new processing method for making said improved insulating foams, and the use of improved insulating foams. for thermal insulation.

SUMMARY OF THE INVENTION

According to a first aspect of the invention, a stabilized aged polyisocyanurate (PIR) containing insulating foam produced at an isocyanate index greater than 180 and/or a polyurethane (PUR) containing insulating foam obtained from an isocyanate index in the range of 123-180 is disclosed. While said foam contains:

- at least one physical blowing agent, characterized by a lambda coefficient for gas ≤12 mW/m.K at 10°C,

at least one CO ₂ scavenging/absorbing compound selected from NaOH and/or KOH, and a reaction product between said CO _{2 scavenging/absorbing compound and CO 2 ,}

- a sealant impervious to gas diffusion, to avoid exchange of air between the foam and the environment, which covers at least 50% of the surfaces of the foam,

where the value is % mol. The CO ₂ in the stabilized aged foam is between 0 and 33% based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam, and the amount of residual CO ₂ scavenging/scavenging compound in the stabilized aged foam is in the range between 0 and 10% of the mass. when calculated on the total weight of the stabilized aged foam.

In accordance with embodiments of the invention, the value of % mol. The CO ₂ in the stabilized aged foam is between 0 and 30%, more preferably between 0 and 27%, based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam.

In accordance with embodiments of the invention, the amount of residual absorbent compound in the stabilized aged foam is between 0 and 5 wt %, more preferably between 0 and 3 wt %, based on the total weight of the stabilized aged foam.

According to embodiments of the invention, the CO ₂ scavenging compound is selected from NaOH and/or KOH.

In accordance with embodiments of the invention, at least one compound that absorbs CO ₂ is selected from NaOH and/or KOH, the value of % mol. The CO ₂ in the stabilized aged foam is between 0 and 33%, preferably between 0 and 30%, more preferably between 0 and 27%, based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam and the amount of residual compound , absorbing CO ₂ in the stabilized aged foam is in the range between 0 and 5 wt. -%, more preferably between 0 and 3 wt. -%, based on the total weight of the stabilized aged foam.

In accordance with embodiments of the invention, the gas diffusion impervious sealant is selected from gas barrier polymer resin layers, such as ethylene-vinyl alcohol (EVOH) copolymer resin layers, or multilayers comprising layers of said resin, and combinations thereof, and wherein at least at least 90%, more preferably 95%, most preferably 90-100%, of the foam surfaces are coated with a sealant impervious to gas diffusion.

In accordance with embodiments of the invention, the gas diffusion impervious sealant is selected from metal foils such as aluminum foil or metal multilayers including aluminum foil, and where 50-95%, more preferably 50-85%, most preferably 50-75 %, from the surfaces of the foam material is covered with a sealant impervious to gas diffusion.

According to embodiments of the invention, blowing agents include HFO blowing agents and/or HCFO blowing agents and/or hydrocarbon blowing agents such as cyclopentane having a gas lambda ≤12 mW/m.K at 10° C., and mixtures thereof.

In accordance with embodiments of the invention, blowing agents include cis-1,1,1,4,4,4-hexafluorobuten-2-ene and/or trans-1-chloro-3,3,3-trifluoropropene.

According to embodiments of the invention, the blowing agent comprises chlorofluorocarbons (CFCs) and/or hydrofluorocarbons (HFCs) and/or hydrochlorofluorocarbons (HCFCs) having a gas lambda value of ≤12 mW/mK at 10°C.

According to a second aspect of the invention, there is disclosed a method for producing a stabilized aged polyisocyanurate (PIR) and/or polyurethane (PUR) containing insulating foam according to the invention, said method comprising:

a) combining and/or mixing at least the following ingredients with an isocyanate index in the range of 123-180 for insulating foam containing polyurethane (PUR), and with an isocyanate index greater than 180 for insulating foam containing polyisocyanurate (PIR)

- a polyisocyanate composition containing one or more polyisocyanate compounds, and

- at least one catalyst compound suitable for use in the production of foam containing polyisocyanurate (PIR) and/or polyurethane (PUR), and

an isocyanate-reactive composition comprising one or more isocyanate-reactive compounds, and

- at least one physical blowing agent characterized by a lambda coefficient for gas ≤12 mW/m.K at 10°C, and

- at least one absorbing CO ₂ compound selected from NaOH and/or KOH, and after that

b) coating at least 50% of the foam surfaces with a gas diffusion-tight sealant to prevent air exchange between the foam and the environment, and thereafter

c) aging the foam to achieve stabilized aged foam, and

characterized in that the foam is coated with a sealant impermeable to diffusion of gas, and the amount of the compound that absorbs CO ₂ is such that the value of % mol. The CO ₂ in the stabilized aged foam would be between 0 and 33% based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam, and the amount of residual absorbent compound in the stabilized aged foam would be between 0 and 10 wt%. when calculated on the total weight of the stabilized aged foam, and where the ratio between the molar amount of absorbent compound added [X] and the theoretical calculated molar amount of CO ₂ [X ₁ ] formed as a result of the reaction between the molar amount of water and the isocyanate present in the composition used to obtain foam, [X]/[X ₁ ] is more than 3.

According to embodiments of the invention, a process for producing a stabilized aged polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention is carried out at an isocyanate index of 180 or more, more preferably at an isocyanate index of more than 250, and the catalyst compound is selected from at least one trimerization catalyst, and the insulation foam is a polyisocyanurate (PIR)-containing foam.

According to embodiments of the invention, the foam is a polyisocyanurate (PIR)-containing insulating foam, and the method is carried out at an isocyanate index of 180 or more, more preferably an isocyanate index of more than 250, and the ratio between the molar amount of added absorbent compound [ X] and the theoretical calculated molar amount of CO ₂ [X1] formed as a result of the reaction between the molar amount of water and the isocyanate present in the composition used to obtain the foam, [X]/[X ₁ ] is more than 6, preferably more than 10, more preferably more than 15.

In accordance with embodiments of the invention, a method for producing a stabilized aged polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention is carried out at an isocyanate index in the range of 123-180, and the catalyst compound is selected from at least one polyurethane catalyst, and the insulating foam is a foam containing polyurethane (PUR).

According to embodiments of the invention, in a process for producing a stabilized aged polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention, polyisocyanate compounds selected from toluene diisocyanate, methylene diphenyl diisocyanate or a polyisocyanate composition containing methylene diphenyl diisocyanate, or mixtures of such polyisocyanates are used. .

According to embodiments of the invention, one or more isocyanate-reactive compounds selected from polyols and polyol blends characterized by average hydroxyl numbers in the range of 50 to 1000, in particular 150 to 700 mg KOH/g and hydroxyl functionalities in the range of 2 to 8, in particular 3 to 8.

According to embodiments of the invention, in a process for producing a stabilized, aged polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention, blowing agents are used in an amount ranging from 1 to 60 parts by weight, preferably from 2 to 45 parts by weight, when calculating one hundred mass parts of compounds reactive with respect to isocyanate.

According to embodiments of the invention, in a process for producing a stabilized, aged polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention, in addition to blowing agents having a lambda coefficient for gas ≤12 mW/m.K at 10°C , additional blowing agents having a lambda coefficient for gas > 12 mW/m.K at 10°C, and the ratio between blowing agents having a lambda coefficient for gas ≤12 mW/m.K at 10°C and additional blowing agents corresponds to a mass ratio of range from 95/5 up to 5/95 when calculated on the total weight of all blowing agents.

According to a third aspect of the invention, the use of polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention is disclosed for thermal insulation, sound insulation and/or insulating/structural panels.

The independent and dependent claims represent specific and preferred features of the invention. Features from dependent claims may be combined with features from independent or other dependent claims, as the case may be.

The above and other characteristics, features and advantages of the present invention will become apparent from the following detailed description of the invention, taken in conjunction with the accompanying drawings, which by way of example illustrate the principles of the invention. This description of the invention is presented by way of example only, without limiting the scope of the invention.

DEFINITIONS AND TERMS

In the context of the present invention, the following terms have the following meaning:

1) The expression "isocyanate index" or "NCO index" or "index" as used herein refers to the ratio between the NCO groups and the isocyanate-reactive hydrogen atoms present in the formulation, expressed as a percentage:

In other words, the NCO index expresses the percentage of isocyanate actually used in the formulation and the amount of isocyanate theoretically required to react with the amount of isocyanate-reactive hydrogen atom used in the formulation.

As it should be noted, the isocyanate index as used herein is considered in terms of the actual polymerization process resulting in the material and involving the isocyanate ingredient and isocyanate-reactive ingredients. The calculation of the isocyanate index does not take into account any isocyanate groups consumed in the preliminary stage to obtain modified polyisocyanates (including such isocyanate derivatives, which in the state of the art are called prepolymers), or any active hydrogen atoms consumed in the preliminary stage, (for example reacted with an isocyanate to form modified polyols or polyamines). Only free isocyanate groups and free isocyanate-reactive hydrogen atoms (including the corresponding hydrogen atoms of water, if used) present in the actual polymerization step are taken into account.

2) The expression "isocyanate-reactive compounds" (also called isocyanate-reactive compounds) and "isocyanate-reactive hydrogen atoms" as used herein for the purpose of isocyanate index calculation refers to the set of active hydrogen atoms in the hydroxyl and amine groups present in isocyanate-reactive compounds; this means that for the purpose of calculating the isocyanate index, in the actual polymerization process, one hydroxyl group is considered to contain one reactive hydrogen atom, one primary amine group is considered to contain one reactive hydrogen atom, and one water molecule is considered to contain two active hydrogen atom.

3) The term "reaction system" as used herein refers to a combination of compounds where the polyisocyanates are kept in one or more containers separate from the isocyanate-reactive components.

4) The term "average nominal hydroxyl functionality" (or "functionality" for short) is used herein to refer to the number average functionality (number of hydroxyl groups per molecule) of a polyol or polyol composition, assuming that it is a number average the functionality (number of active hydrogen atoms per molecule) of the initiator(s) used in their preparation, although in practice it will often be somewhat less due to the presence of some terminal unsaturation.

5) The word "average" refers to the number average unless otherwise indicated.

6) The term "trimerization catalyst" as used herein refers to a catalyst capable of catalyzing (promoting) the formation of isocyanurate groups from polyisocyanates. This means that isocyanates can react with each other to form macromolecules with isocyanurate structures (polyisocyanurate=PIR). The reactions of isocyanates-polyols and isocyanates-isocyanates (homopolymerization) can take place simultaneously or in direct sequence with the formation of macromolecules with urethane and isocyanurate structures (PIR-PUR).

7) The term "polyisocyanurate-containing material" (PIR) or "PIR foam" as used herein refers to a material obtained with an isocyanate index of 180 or more, more preferably with an isocyanate index of more than 250.

8) The term "polyurethane-containing material" (PUR) or "PUR foam" as used herein refers to a material obtained with an isocyanate index in the range of 123-180.

9) The term "foam density" as used herein refers to the density measured on foam samples and calculated as mass/volume and expressed in kg/m ³ .

10) Measurements of "thermal conductivity" are carried out at 10°C in accordance with ISO8301 document using heat flow meter (HFT) equipment. The terms lambda factor, λ factor, or k factor, as used herein, refer to the thermal conductivity of a material, usually expressed in mW/m.K. The lower the lambda coefficient, the better the thermal insulation performance will be.

11) The closed and open cell content of the foam is measured using a pycnometer in accordance with ISO 4590.

12) The terms “stabilized lambda”, “stabilized λ”, and “stabilized k” for foam as used herein refer to thermal conductivity at 10°C (according to ISO8301) that does not change over a long period of time. time period (variation≤0.5mW/m.K). For the foams of the invention, a stabilized lambda coefficient is achieved after the time required for CO ₂ scavenging using the CO ₂ scavenging compound of the invention (after completion of the CO ₂ scavenging/scavenging process). Completion of the CO ₂ scavenging/absorption process can take a period of time ranging from hours up to several months, depending on the size of the foam and the type of sealant used.

13) The term "aging" refers to the processing of the foam, where the foam is kept at a certain temperature for a given period of time.

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be described in relation to specific embodiments.

It should be noted that the term "comprising" used in the claims should not be interpreted as being limited to the means listed after it; it does not exclude other elements or steps. Thus, it should be interpreted as indicating the presence of the claimed features, steps, or components to which reference is made, but does not preclude the presence or addition of one or more other representatives selected from the features, steps, or components, or groups thereof. Thus, the scope of the expression "device comprising means A and B" should not be limited to devices consisting only of components A and B. This means that, with respect to the present invention, the only significant components of the device are A and B.

Throughout the course of this specification, reference is made to "one embodiment" or "an embodiment". Such references indicate that one particular feature described with respect to an embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" in various places throughout the course of this specification does not necessarily refer to the same embodiment in all cases, although it is possible. Still further, specific features or characteristics may be combined in any manner suitable for use in one or more embodiments, as would be apparent to those skilled in the art.

As it is to be understood, despite the discussion of preferred embodiments and/or materials for suggesting embodiments of the present invention, various modifications or changes may be made without deviating from the scope and spirit of the present invention.

The present invention relates to insulating foams containing polyisocyanurate (PIR) and/or polyurethane (PUR), which, unfortunately, are characterized by degraded insulation values due to the formation of CO ₂ .

When using methods of the prior art (for example, US 5,649,430) to obtain (semi)rigid containing polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foams, a CO ₂ scavenger/absorber (NaOH) was added at a maximum amount corresponding to a molar ratio of 3: 1 when expressed as the ratio between the CO ₂ scavenger (NaOH) and the theoretical number of moles of carbon dioxide formed as a result of the reaction between the isocyanate and water present in the composition.

However, it has been found that under such conditions, the stabilized lambda coefficient is only marginally improved compared to that of the same PU foam in the absence of scavenger. As it was found after measuring the gas composition of the cell, there is still a very significant amount of carbon dioxide, which explains the unsatisfactory decrease in the lambda coefficient.

It has been found that using more than the recommended amount of a CO ₂ scavenger compound selected from potassium hydroxide and/or sodium hydroxide results in lower stabilized aged lambda values corresponding to lower levels of measured carbon dioxide.

It has also been found that, depending on the type of PU foam and depending on the processing conditions, different amounts of scavenger are required to obtain a significant reduction in the stabilized aged lambda coefficient.

It has also been found that it is possible to remove all of the carbon dioxide by using excessively large amounts of scavenger, but with the following disadvantages:

Some unreacted sodium hydroxide remains in the foam, which is not desirable as it could lead to environmental, health and safety, and corrosion problems in the final products.

The presence of large amounts of solids in the foam (as reaction products and as unreacted scavenger) can adversely affect foam quality, physical and mechanical properties, and potentially also thermal conductivity.

In order to solve the above problems, the present invention describes the conditions and method that makes it possible to optimize the use of the scavenger in order to:

Maximizing the reduction of the stabilized aged lambda coefficient,

Minimizing the residual amount of unreacted sodium hydroxide.

Thus, in the present invention, a method has been developed in which an optimized amount of a CO ₂ scavenger compound is added to the compositions used to obtain said foams, which captures the main amount of the CO ₂ compound formed during foaming and aging, and which minimizes the amount of residual unreacted CO ₂ absorbent compound, combined with the addition of a gas impermeable sealant and the use of a blowing agent having a lambda value ≤12 mW/m.K.

Therefore, the present invention relates to novel polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foams having significantly improved thermal insulation values maintained over the average economic life of the foam, a new processing method for making said improved thermal insulating foams, and the use of improved insulating foam materials for thermal insulation.

According to a first aspect , a polyisocyanurate (PIR) and/or polyurethane (PUR) containing insulating foam is disclosed that exhibits significantly improved thermal insulation performance over the average economic life of the foam.

The polyisocyanurate (PIR) and/or polyurethane (PUR) based foam material of the invention contains:

- at least one physical blowing agent, characterized by a lambda coefficient for gas ≤12 mW/m.K at 10°C,

at least one CO ₂ scavenging compound selected from KOH and/or NaOH and/or a reaction product between said CO ₂ scavenging compound and CO ₂ ,

a sealant to prevent air exchange between the foam and the environment (gas diffusion sealant) that covers at least 50% of the foam surfaces.

In accordance with the invention, the value of % mol. The CO ₂ in the stabilized aged foam ranges between 0 and 33% based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam, and the amount of residual absorbent compound in the stabilized aged foam ranges between 0 and 10 wt%. when calculated on the total weight of the stabilized aged foam.

In accordance with embodiments of the invention, the foam corresponding to the invention is preferably characterized by the value of % mol. CO ₂ in the stabilized aged foam in the range between 0 and 30%, more preferably between 0 and 27%, based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam.

According to embodiments, the foam of the invention preferably has an amount of residual absorbent compound in the stabilized aged foam in the range of between 0 and 5 wt %, more preferably between 0 and 3 wt %, based on the total weight of the stabilized aged foam.

According to embodiments, the at least one CO ₂ scavenging compound is selected from NaOH and/or KOH and combinations thereof.

In accordance with embodiments, at least one compound that absorbs CO ₂ is selected from NaOH and/or KOH, and the value of % mol. The CO ₂ in the stabilized aged foam ranges between 0 and 33%, preferably between 0 and 30%, more preferably between 0 and 27%, based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam.

According to embodiments, at least one CO ₂ scavenging compound is selected from NaOH and/or KOH, and the amount of residual scavenging compound in the stabilized aged foam is between 0 and 5 wt %, more preferably between 0 and 3% wt., based on the total weight of the stabilized aged foam.

In accordance with embodiments containing polyisocyanurate (PIR) and/or polyurethane (PUR), the insulating foam of the invention is characterized by a stabilized aged lambda coefficient that is at least 1 mW/m.K at 10° C. less than which is the case for prior art polyisocyanurate (PIR) and/or polyurethane (PUR) based insulating foams using equal amounts and type of blowing agents, but without the use of CO ₂ scavengers, after the same period of time.

In accordance with embodiments containing polyisocyanurate (PIR) and/or polyurethane (PUR), the insulating foam according to the invention is maintained under air diffusion impermeable conditions and the gas diffusion impermeable sealant is selected from gas barrier polymer resin layers, such as copolymer resin layers. ethylene-vinyl alcohol (EVOH), or multilayers comprising layers of said resin, and combinations thereof, and at least 50%, preferably at least 90%, more preferably 95%, most preferably 90-100%, surfaces of the foam material are covered with a sealant that is impervious to gas diffusion.

According to preferred embodiments, the sealant is a liquid pervious layer, preferably including at least an ethylene vinyl alcohol (EVOH) resin layer as the gas barrier polymer.

According to embodiments, the sealant may include at least one layer of a gas barrier polymer selected from ethylene-vinyl alcohol (EVOH) copolymer, polyvinyl alcohol (PVOH) and its copolymers, polyvinylidene chloride (PVDC), polyamide (PA), polyethylene terephthalate ( PET), polyketones (RK), polyacrylonitriles (PAN) and combinations thereof. The gas barrier polymer layer may further comprise one or more additional layers which may, for example, comprise or consist of the following: a thermoplastic polymer such as polyethylene and/or polypropylene. In addition, sealants suitable for use in the present invention are disclosed in EP 3 000 592.

In accordance with embodiments containing polyisocyanurate (PIR) and/or polyurethane (PUR), the insulating foam according to the invention is maintained under air diffusion impermeable conditions and the gas diffusion impermeable sealant is selected from metal foils, such as aluminum foil, or metal multilayers comprising aluminum foil, and wherein at least 50%, preferably 50-95%, more preferably 50-85%, most preferably 50-75%, of the foam surfaces are coated with a gas diffusion-tight sealant.

In accordance with embodiments containing polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention may additionally (optionally) contain one or more surfactants, one or more flame retardants, water, one or more antioxidants, one or more auxiliary blowing agents, one or more auxiliary urethane catalysts, one or more auxiliary trimerization catalysts, or combinations thereof.

Polyisocyanurate (PIR) and/or polyurethane (PUR) containing insulating foams according to the invention will result in (after a stabilization period when the scavenger/absorber captures CO ₂ ) insulating foams having a substantially low thermal conductivity. Said insulating foams containing polyisocyanurate (PIR) and/or polyurethane (PUR) over a long period of time can be characterized by a stabilized aged thermal conductivity, which is less than the initial thermal conductivity immediately after the production of the foam due to the consumption of CO ₂ by the CO ₂ absorber, the use of blowing agents, characterized by a gas lambda coefficient ≤12 mW/m.K at 10°C, such as blowing agents including HFO/HCFO, and diffusion tight conditions.

According to embodiments, the CO ₂ scavenger compound may be selected from NaOH particles/beads having, for example, an average diameter of >100 micrometers (μm) and <1-2 mm.

According to preferred embodiments, the blowing agents are selected from at least HFO blowing agents and/or HCFO blowing agents and/or hydrocarbons such as cyclopentane having a gas lambda ≤12 mW/m.K at 10°C.

In accordance with preferred embodiments, blowing agents include at least HFO blowing agents and/or HCFO blowing agents and/or a hydrocarbon such as cyclopentane having a gas lambda ≤12 mW/m.K at 10°C.

According to embodiments, blowing agents include at least 3,3,3-trifluoropropene, 1,2,3,3,3-pentafluoropropene, cis- and/or trans-1,3,3,3-tetrafluoropropene and/ or 2,3,3,3-tetrafluoropropene and/or 1,1,1,4,4,4,-hexafluorobut-2-ene and/or 1-chloro-3,3,3-trifluoropropene and/or 2- chloro-3,3,3-trifluoropropene and mixtures thereof.

Preferred examples of commercially available and suitable HFO blowing gases are Honeywell HFO-1234ze (trade name from Honeywell for trans-1,3,3,3-tetrafluoropropene) or Opteon® 1100 (trade name from Chemours for cis -1,1,1,4,4,4-hexafluorobut-2-ene CF ₃ CH=CHCF ₃ ).

A preferred example of a commercially available and suitable HCFO blowing gas is Honeywell Solstice® 1233zd (Honeywell trade name for trans-1-chloro-3,3,3-trifluoropropene CHCl=CHCF ₃ ) or Forane® 1233zd (trade name name from Arkema for trans-1-chloro-3,3,3-trifluoropropene CHCl=CHCF ₃ ).

According to embodiments, the foam according to the invention may contain blowing agents having a gas lambda value of ≤12 mW/m.K at 10° C. and selected from hydrofluorocarbons (HFCs) and/or hydrocarbons such as cyclopentane and mixtures thereof.

According to embodiments, the foam according to the invention may further contain blowing agents such as hydrocarbons selected from isopentane, isobutane, n-pentane and mixtures thereof and characterized by a gas lambda coefficient > 12 mW/m.K at 10° FROM.

According to embodiments, blowing agents may further include additional blowing agents selected from formic acid, methyl formate, dimethyl ether, water, methylene chloride, acetone, t-butanol, argon, krypton, xenon, and mixtures thereof.

According to a second aspect of the invention, a process is disclosed for producing an insulating foam material according to the invention containing polyisocyanurate (PIR) and/or polyurethane (PUR).

The method for producing polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention may include combining and/or mixing at an isocyanate index in the range of 123-180 for an insulating foam containing polyurethane (PUR) and at an isocyanate index, greater than 180 for an insulating foam containing polyisocyanurate (PIR) of at least the following compounds:

- a polyisocyanate composition containing one or more polyisocyanate compounds, and

- at least one catalyst compound suitable for use in the production of foam containing polyisocyanurate (PIR) and/or polyurethane (PUR), and

an isocyanate-reactive composition comprising one or more isocyanate-reactive compounds, and

- at least one physical blowing agent characterized by a lambda coefficient for gas ≤12 mW/m.K at 10°C, and

at least one CO ₂ scavenging compound selected from NaOH and/or KOH, and reaction products between said CO ₂ scavenging compound and CO ₂ ,

characterized in that the foam is coated with a sealant impervious to diffusion of gas, and the amount of compounds that absorb CO ₂ is such that the value of % mol. The CO ₂ in the stabilized aged foam would be between 0 and 33% based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam, and the amount of residual absorbent compound in the stabilized aged foam would be between 0 and 10 wt%. when calculated on the total weight of the stabilized aged foam, and where the ratio between the molar amount of absorbent compound added [X] and the theoretical calculated molar amount of CO ₂ [X ₁ ] formed as a result of the reaction between the molar amount of water and the isocyanate present in the composition used to obtain foam, [X]/[X ₁ ] is more than 3.

In accordance with the invention, an optimized amount of a CO ₂ scavenger compound must be added to the compositions used to prepare the PIR and/or PUR polymer-containing insulating foam of the invention, wherein said optimized amount of the CO ₂ scavenger compound traps the CO ₂ compound formed during foaming and aging, which minimizes the amount of residual unreacted CO ₂ scavenger compound. To achieve this goal, the molar amount of added scavenging compound [X] must be optimized in accordance with the methodology of the present invention.

According to embodiments, the scavenging compound is selected from NaOH and/or KOH and the [X]/[X ₁ ] molar ratio is greater than 3, preferably greater than 6, more preferably greater than 10, most preferably greater than 15. Where [X] = molar amount of scavenging compound added [X], and [X ₁ ] = theoretical calculated molar amount of CO ₂ compound formed from the reaction between the molar amount of water and the isocyanate present in the formulation used to make the foam .

According to embodiments, the foam is an insulating foam containing polyurethane (PUR), the absorbent compound is selected from NaOH and/or KOH, and the molar ratio [X]/[X ₁ ] is greater than 3. Wherein [X] = molar amount added scavenging compound [X], and [X ₁ ] = theoretical calculated molar amount of CO ₂ compound formed from the reaction between the molar amount of water and the isocyanate present in the formulation used to make the foam.

According to embodiments, the foam is a polyisocyanurate (PIR) insulating foam, the absorbent compound is selected from NaOH and/or KOH, and the [X]/[X ₁ ] molar ratio is greater than 6, more preferably greater than 10, most preferably greater than 15. Where [X] = the molar amount of absorbent compound [X] added, and [X ₁ ] = the theoretical calculated molar amount of CO ₂ compound formed by the reaction between the molar amount of water and the isocyanate present in the composition used to make foam.

There are many different orders of contact or combination of compounds required to obtain the insulating foam of the present invention. As will be recognized by those skilled in the art, varying the order in which the compounds are added falls within the scope of the present invention.

According to embodiments, combining and mixing for the CO ₂ scavenging compound(s) can be carried out by adding said CO ₂ scavenging compound(s) to the isocyanate-reactive composition prior to combining and/or mixing with the polyisocyanate composition (in other words, the CO ₂ absorbing compound(s) are added to the polyisocyanate-reactive composition until a reaction mixture is formed).

According to embodiments, the combination and mixing for the CO ₂ scavenging compound(s) can be carried out by adding said CO ₂ scavenging compound(s) to the polyisocyanate composition prior to combining and/or mixing with the CO 2 -reactive composition. in relation to the isocyanate, (in other words, the compound (compounds), absorbing CO ₂ add to the polyisocyanate composition to create a reaction mixture).

According to embodiments, the combination and mixing for the CO ₂ scavenging compound(s) can be carried out by adding said CO ₂ scavenging compound(s) to the reaction composition, wherein said reaction composition is created by combining and/or mixing the polyisocyanate composition, the isocyanate-reactive composition, the catalyst compound(s) and the blowing agent(s), and optionally other ingredients (in other words, the CO ₂ scavenging compound(s) are added to the reaction mixture).

According to embodiments, the combination and mixing for the CO ₂ scavenging compound(s) can be carried out by adding said CO ₂ scavenging compound(s) after laying down the reaction composition, wherein said reaction composition is created by combining and/ or mixing the polyisocyanate composition, the isocyanate-reactive composition, the catalyst compound(s), the blowing agent(s), and optionally other ingredients.

According to embodiments, the combination and mixing for the CO ₂ scavenging compound(s) can be carried out by adding said CO ₂ scavenging compound(s) to the reaction composition present in the mold, whereby said reaction composition is created by combining and/or mixing the polyisocyanate composition, the isocyanate-reactive composition, the catalyst compound(s), the blowing agent(s), and optionally other ingredients.

According to embodiments, the combining and mixing for the CO ₂ scavenging compound(s) can be carried out by adding said CO ₂ scavenging compound(s) to the mold prior to injecting the reaction composition into the mold, wherein said the reactive composition is created by combining and/or mixing the polyisocyanate composition, the isocyanate-reactive composition, the catalyst compound(s), the blowing agent(s), and optionally other ingredients.

According to embodiments, the process for making the insulating foam of the invention may further comprise combining and mixing one or more surfactants, one or more additives such as nucleating agents, adhesion promoters, one or more flame retardants, water, one or more antioxidants, one or more auxiliary blowing agents, one or more auxiliary urethane catalysts, one or more auxiliary trimerization catalysts, one or more foaming catalysts, or combinations thereof.

According to embodiments, the method for producing an insulating foam according to the invention is carried out at an isocyanate index of 180 or more, more preferably an isocyanate index of more than 250, and the insulating foam is a polyisocyanurate (PIR)-containing foam.

According to embodiments, a method for producing an insulating foam according to the invention is carried out at an isocyanate index in the range of 123-180, and the insulating foam is a foam containing polyurethane (PUR).

According to embodiments, the insulating foam is a polyisocyanurate (PIR) insulating foam and the catalyst compound is selected from at least a trimerization catalyst compound, said catalyst being present in the foam composition in a catalytically effective amount. Suitable trimerization catalyst compounds for use herein include, but are not limited to, quaternary ammonium hydroxides and salts, alkali metal and alkaline earth metal hydroxides, alkoxides and carboxylates, e.g. potassium acetate and potassium 2-ethylhexanoate, certain tertiary amines and minor metal carboxylates.

According to embodiments, the insulating foam is a polyurethane (PUR) insulating foam and the catalyst compound is selected from at least a polyurethane catalyst compound, said catalyst being present in the foam composition in a catalytically effective amount. Suitable polyurethane catalyst compounds for use herein include, but are not limited to, metal salt catalysts such as organotin compounds and amine compounds such as triethylenediamine (TEDA), N-methylimidazole, 1,2- dimethylimidazole, N-methylmorpholine, N-ethylmorpholine, triethylamine, N,N'-dimethylpiperazine, 1,3,5-tris(dimethylaminopropyl)hexahydrotriazine, 2,4,6-tris(dimethylaminomethyl)phenol, N-methyldicyclohexylamine, pentamethyldipropylenetriamine, N -methyl-N'-(2-dimethylamino)ethylpiperazine, tributylamine, pentamethyldiethylenetriamine, hexamethyltriethylenetetraamine, heptamethyltetraethylenepentaamine, dimethylaminocyclohexylamine, pentamethyldipropylenetriamine, triethanolamine, dimethylethanolamine, bis(dimethylaminoethyl)ether, tris(3-dimethylamino)propylamine or their acid-blocked derivatives, and the like, as well as any mixture thereof.

According to embodiments, the amount of CO ₂ scavenger compound added to a given PUR or PIR foam formulation should be adjusted depending on the amount of CO ₂ compound produced. Preferred amounts of CO ₂ absorbent compounds (eg, NaOH beads) are in the range of 1-25% by weight. when calculated on the total weight of the composition of the foam, more preferably in the range of 2-20 wt. -%, which result in high quality foams (ie, stable, fine-meshed, defect-free).

According to embodiments, the polyisocyanate compounds used in the process for preparing the polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam of the invention are selected from organic isocyanates containing a plurality of isocyanate groups, including aliphatic isocyanates such as hexamethylene diisocyanate, and more preferably aromatic isocyanates such as m- and p-phenylene diisocyanate, tolylene-2,4- and -2,6-diisocyanates, diphenylmethane-4,4'-diisocyanate, chlorophenylene-2,4-diisocyanate, naphthylene-1, 5-diisocyanate, diphenylene-4,4'-diisocyanate, 4,4'-diisocyanate-3,3'-dimethylbiphenyl, 3-methyldiphenylmethane-4,4'-diisocyanate and diphenyl ether diisocyanate, cycloaliphatic diisocyanates such as cyclohexane- 2,4- and -2,3-diisocyanates, 1-methylcyclohexyl-2,4- and -2,6-diisocyanates, and mixtures thereof and bis(isocyanatocyclohexyl)methane and triisocyanates such as 2,4,6-triisocyanatotoluene and 2,4,4'-triisocyanatodiphenyl simple e fir.

According to embodiments, the polyisocyanate composition comprises mixtures of polyisocyanates. For example, a mixture of tolylene diisocyanate isomers, such as commercially available mixtures of 2,4- and 2,6-isomers, as well as a mixture of di- and higher polyisocyanates produced from the phosgenation of aniline/formaldehyde condensates. Such mixtures are well known in the art and include crude phosgenation products containing mixtures of methylene bridged polyphenyl polyisocyanates, including diisocyanate, triisocyanate and higher polyisocyanates, together with any phosgenation by-products.

Preferred polyisocyanate compositions of the present invention are those wherein the polyisocyanate is an aromatic diisocyanate or a high functionality polyisocyanate, in particular crude mixtures of methylene bridged polyphenyl polyisocyanates, including diisocyanates, triisocyanates and high functionality polyisocyanates. Polyphenyl polyisocyanates containing methylene bridges (for example, methylene diphenyl diisocyanate, abbreviated as MDI) are well known in the state of the art and are described by the general formula I, where n is one or more, and for the case of crude mixtures is an average value of more than one. They are obtained by phosgenation of appropriate mixtures of polyamines obtained by the condensation of aniline and formaldehyde.

(I)

(I)

Other suitable polyisocyanate compositions may include isocyanate-terminated prepolymers obtained by reacting an excess of a high-functionality diisocyanate or polyisocyanate with a hydroxyl-terminated polyester or hydroxyl-terminated polyether, and products obtained by reaction between an excess of a high functionality diisocyanate or polyisocyanate and a monomeric polyol or a mixture of monomeric polyols such as ethylene glycol, trimethylolpropane or butanediol. One preferred class of isocyanate-terminated prepolymers are isocyanate-terminated green blend prepolymers of methylene-bridged polyphenyl polyisocyanates, including diisocyanates, triisocyanates, and polyisocyanates, characterized by superior functionality.

According to embodiments, the polyisocyanate compounds in the polyisocyanate composition are selected from toluene diisocyanate, methylene diphenyl diisocyanate, or a polyisocyanate composition containing methylene diphenyl diisocyanate, or mixtures of such polyisocyanates.

In accordance with embodiments, the one or more isocyanate-reactive compounds used in the process for preparing the polyisocyanurate (PIR) and/or polyurethane (PUR)-containing insulation foam of the invention comprise any of the relevant compounds known in the art. obtaining said foams. Of particular importance in the production of rigid foams are polyols and polyol blends having average hydroxyl numbers in the range of 50 to 1000, in particular 150 to 700 mg KOH/g and hydroxyl functionalities in the range of 2 to 8, in particular 3 to 8 Suitable polyols have been fully described in the prior art and include reaction products between alkylene oxides, eg ethylene oxide and/or propylene oxide, and initiators having 2 to 8 active hydrogen atoms per molecule. Suitable initiators include: polyols such as glycerol, trimethylolpropane, triethanolamine, pentaerythritol, sorbitol and sucrose; polyamines such as ethylenediamine, tolylenediamine (TDA), diaminodiphenylmethane (DADPM) and polymethylenepolyphenylenepolyamines; and amino alcohols, for example ethanolamine and diethanolamine; and mixtures of such initiators. Other suitable polymeric polyols include polyesters obtained by condensing glycols and high functionality polyols with dicarboxylic or polycarboxylic acids at appropriate proportions. Still further suitable polymeric polyols include hydroxyl-terminated polythioethers, polyamides, polyesteramides, polycarbonates, polyacetals, polyolefins, and polysiloxanes.

The amounts of the polyisocyanate compositions and one or more isocyanate-reactive compounds reacted will depend on the nature of the polyisocyanurate (PIR) and/or polyurethane (PUR)-containing insulation foam produced and can be easily determined by those skilled in the art. technology.

According to preferred embodiments, the blowing agents are selected from at least HFO blowing agents and/or HCFO blowing agents and/or hydrocarbons such as cyclopentane having a gas lambda ≤12 mW/m.K at 10°C.

In accordance with preferred embodiments, blowing agents include at least HFO blowing agents and/or HCFO blowing agents and/or a hydrocarbon such as cyclopentane having a gas lambda ≤12 mW/m.K at 10°C.

According to embodiments, blowing agents include at least 3,3,3-trifluoropropene, 1,2,3,3,3-pentafluoropropene, cis- and/or trans-1,3,3,3-tetrafluoropropene and/ or 2,3,3,3-tetrafluoropropene and/or 1,1,1,4,4,4-hexafluorobut-2-ene and/or 1-chloro-3,3,3-trifluoropropene and/or 2-chloro -3,3,3-trifluoropropene and mixtures thereof.

Preferred examples of commercially available and suitable HFO blowing gases are Honeywell HFO-1234ze (trade name from Honeywell for trans-1,3,3,3-tetrafluoropropene) or Opteon® 1100 (trade name from Chemours for cis -1,1,1,4,4,4-hexafluorobut-2-ene CF ₃ CH=CHCF ₃ ).

A preferred example of a commercially available and suitable HCFO blowing gas is Honeywell Solstice® 1233zd (Honeywell trade name for trans-1-chloro-3,3,3-trifluoropropene CHCl=CHCF ₃ ) or Forane® 1233zd (trade name name from Arkema for trans-1-chloro-3,3,3-trifluoropropene CHCl=CHCF ₃ ).

According to embodiments, the foam according to the invention may contain blowing agents having a gas lambda value of ≤12 mW/m.K at 10° C. and selected from hydrofluorocarbons (HFCs) and/or hydrocarbons such as cyclopentane and mixtures thereof.

According to embodiments, the foam according to the invention may further contain blowing agents such as hydrocarbons selected from isopentane, isobutane, n-pentane and mixtures thereof and characterized by a gas lambda coefficient > 12 mW/m.K at 10° FROM.

According to embodiments, blowing agents may further include additional blowing agents selected from formic acid, methyl formate, dimethyl ether, water, methylene chloride, acetone, t-butanol, argon, krypton, xenon, and mixtures thereof.

The amount of blowing agent used may vary based on, for example, the intended use and application of the foam product and the desired properties and density of the foam. The blowing agent may be present in amounts ranging from 1 to 60 mass parts (m. h.) calculated on one hundred mass parts of compounds reactive with isocyanate, (polyol), more preferably from 2 to 45 w. h. In the case of the (optional) use of water as one of the blowing agents in the foam composition, the amount of water is preferably limited to amounts up to 15 ppm, preferably < 5 ppm, more preferably < 3 ppm.

According to embodiments, at least one blowing agent having a gas lambda ≤12 mW/m.K at 10°C may include additional blowing agents having a gas lambda >12 mW/m.K at 10° C, and the ratio between the blowing agent having a lambda coefficient for gas ≤12 mW/m.K at 10° C. and the additional blowing agents corresponds to a weight ratio ranging from 95/5 up to 5/95, based on the combined weight of all blowing agents.

According to embodiments, at least one blowing agent is selected from HCFO and/or HFO blowing agents and includes cyclopentane or mixtures of cyclopentane and isopentane as an additional blowing agent, and the ratio between the HCFO and/or HFO blowing agents and the cyclopentane blowing agent corresponds to a weight ratio in range from 95/5 up to 5/95 when calculated on the total weight of all blowing agents.

According to embodiments, the insulating foam of the invention comprising polyisocyanurate (PIR) and/or polyurethane (PUR) is a rigid insulating foam.

According to embodiments containing polyisocyanurate (PIR) and/or polyurethane (PUR), the insulating foam according to the invention is characterized by a foam density < 45 kg/m ³ and a stabilized thermal conductivity < 20 mW/m.K at 10° C., preferably in the range from 14 up to 20 mW/m.K at 10°C.

According to embodiments containing polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to the invention is characterized by a density of the foam > 45 kg/m ³ and a stabilized thermal conductivity < 25 mW/m.K at 10°C, preferably in the range from 14 up to 25 mW/m.K at 10°C.

In accordance with embodiments containing polyisocyanurate (PIR) and/or polyurethane (PUR), the insulating foam of the invention has a closed cell level of greater than 70% based on the combined number of closed and open cells present in the material.

In accordance with embodiments, the polyisocyanurate (PIR) and/or polyurethane (PUR)-containing foam of the present invention can be used as a thermal insulator, such as building thermal insulation foam, thermal insulation foam for electrical equipment, or pipe insulation. The polyisocyanurate (PIR) and/or polyurethane (PUR) containing insulating foam of the present invention satisfies all requirements for use as an insulating material, especially due to its low thermal conductivity value.

FIGURES

Figure 1 illustrates the effect of a CO ₂ scavenger on the lambda coefficient (measured at 10°C) as a function of time (aging at room temperature) for 1 foam obtained in accordance with the invention (example 1) and for a comparative foam (comparative example 1) .

Figure 2 illustrates the effect of a blowing agent on the lambda coefficient (measured at 10°C) versus time (aging at room temperature) for 3 foams made according to the invention (example 1, example 2 and example 3) and for 2 comparative foams (comparative examples 2+3).

Figure 3 illustrates the effect of diffusion impermeable conditions of the foam on the lambda coefficient (measured at 10° C.) as a function of time (aging at room temperature) for the foam obtained in accordance with the invention (example 1) and for the comparative foam (comparative example four).

Figure 4 illustrates the lambda coefficient measured at 10°C for examples A2 - A4 according to the invention and comparative examples A0 - A1 as a function of time (aging at room temperature) using HCFO as a physical blowing agent and various amounts of CO ₂ scavenger (illustrating the amount of CO ₂ scavenger required).

Figure 5 illustrates the lambda coefficient measured at 10°C for examples B2 - B3 according to the invention and comparative examples B0 - B1 as a function of time (aging at room temperature) using cyclopentane as a physical blowing agent and various amounts of CO ₂ scavenger (illustrating the amount of CO ₂ scavenger required).

Figure 6 illustrates the lambda coefficient measured at 10°C for examples D2 - D3 according to the invention and comparative examples D0 - D1 as a function of time (aging at room temperature) using HCFO as a physical blowing agent and various amounts of CO ₂ scavenger (illustrating the amount of CO ₂ scavenger required).

MEASUREMENT METHODS

1. Titration Method for Determination of Residual Scavenger (NaOH) in Stabilized Aged Foam

The titration method is used to determine the residual amount of NaOH in stabilized aged foam based on the following reaction (which takes place in stabilized aged foam ):

2NaOH+CO ₂ → Na ₂ CO ₃ + H ₂ O [1]

Titration method:

Sufficient foam is crushed and mixed with water in a closed system (hermetically sealed mixer)

filter out the water

A measured amount of this filtered water is titrated using a solution of HCl (0.5 N).

As a result of titration, it is possible to determine the residual compound NaOH

Titration reaction:

NaOH+HCl → NaCl+H ₂ O

2. Method for Determining the Amount of NaOH Compound Required to Achieve Optimum CO ₂ Removal and Minimal Residual NaOH Compound in Aged Foam

Under actual process conditions or laboratory scale conditions, in the absence of scavenger (NaOH), a foam sample is obtained having the selected composition.

This sample (sufficiently sealed using a diffusion-tight lining according to the invention) is aged until a stable lambda coefficient is achieved (accelerated aging can be carried out).

Immediately after stabilization of the lambda coefficient at the end of aging, the amount of CO ₂ is measured (using a Cell Gas Analysis (CGA) device). This is the cumulative amount of CO ₂ formed in the aged foam sample in the absence of scavenger.

Calculate the "stoichiometric" amount of NaOH required to remove the measured amount of CO ₂ in the sample (referring to the above single reaction [1]). Since 2 mol of NaOH react with 1 mol of CO ₂ , the molar ratio of NaOH / CO ₂ \u003d 2: 1.

A slight excess of the calculated amount of NaOH is used, according to actual process conditions or laboratory scale conditions, a new prototype is prepared which includes the NaOH scavenger/scavenger.

This new sample (sufficiently sealed using a diffusion-tight lining according to the invention) is aged until a stable lambda coefficient is achieved (accelerated aging can be used).

Once the aged lambda coefficient is stabilized by titration, the residual NaOH compound is measured, the residual CO ₂ compound is measured using a CGA device.

As a result of successive approximation, the exact amount of NaOH can be fine-tuned to achieve the desired CO ₂ removal and/or to obtain the desired amount of residual NaOH compound.

EXAMPLES

Used chemical compounds :

- Polyisocyanate Suprasec® 5025 (S5025), standard functionality MDI polymer composition showing NCO%=31.0 and average functionality=2.7 and viscosity at 25°C=210 mPa.s

- Polyisocyanate Suprasec® 2085 (S2085), high functionality MDI polymer composition showing NCO%=30.5 and average functionality=2.9 and viscosity at 25°C=625 mPa.s

- Foam stabilizer: silicon surfactant

- Catalyst 1: N,N-dimethylcyclohexylamine

- Catalyst 2: pentamethyldiethylenetriamine

- Catalyst 3: 1,3,5-tris(3-(dimethylamino)propyl)hexahydro-s-triazine

- Catalyst 4: potassium octanoate catalyst

- Catalyst 5: potassium acetate catalyst

- Sodium hydroxide beads (from Sigma Aldrich), NaOH (20-40 mesh)

- Sodium hydroxide micrograins from Prochimica

- Polyol 1: sucrose/DELA initiated polyether polyol (OHv=585 mg KOH/g, viscosity at 25°C=4400 mPa.s)

- Polyol 2: DADPM/DEG initiated polyether polyol (OHv=310 mg KOH/g, viscosity at 25°C=2000 mPa.s)

- Polyol 3: polyether polyol initiated using glycerol/sorbitol (OHv=500 mg KOH/g, viscosity at 25°C=610 mPa.s)

- Polyol 4: Aromatic polyester polyol based on PTA (OHv=240 mg KOH/g, viscosity at 25°C=3000 mPa.s)

- Flame retardant 1: tris(chloroisopropyl)phosphate (TCPP)

- Water

- Foaming agent n-pentane

- Foaming agent cyclopentane

- HCFO Solstice® 1233zd foaming agent from Honeywell - trans-1-chloro-3,3,3-trifluoropropene (CHCl=CHCF ₃ )

- Foamer HFO Opteon® 1100 from Chemours (cis-1,1,1,4,4,4-hexafluorobut-2-ene CF ₃ CH=CHCF ₃ )

- HFC foaming agent Enovate® 245fa from Honeywell

1. Production of insulation foam containing PUR polymer using a CO absorber ₂ and HCFO blowing agent (example 1) and comparative example 1 without the use of a CO scavenger ₂ (illustrating the effect of a CO absorber ₂ )

Two insulating foams were made containing polyurethane using an isocyanate index of 123.

Table 1 summarizes the reaction system and the amounts of ingredients used in parts by weight (m.h.) for implementation

1) Example 1 according to the present invention using NaOH as CO ₂ scavenger and Solstice® 1233zd HCFO blowing agent and

2) Comparative example 1 without using CO ₂ scavenger and using HCFO 1233zd blowing agent as blowing agent.

Both foams were produced in a closed mold measuring 30 cm (long) by 30 cm (wide) by 3 cm (thick) using the same gas diffusion-tight sealant according to the invention.

reaction system Comparative example 1, m.h. An example of the invention (example 1), m.h. Polyol 1 29.7 29.7 Polyol 2 fifteen fifteen Polyol 3 50.8 50.8 Catalyst 1 1.9 1.9 Catalyst 2 0.5 0.5 Catalyst 3 0.1 0.1 Foam Stabilizer 0.7 0.7 Water 1.3 1.3 Foaming agent HCFO (Solstice® ^1233zd ) 7 7 CO ₂ absorber (NaOH beads) 0 21.6 Molar ratio [X]/[X1] ^(**) 0 7.5:1 S5025 162 162 Isocyanate index 123 123 Foam density (kg/m ³ ) 63.5 71.7 Facing Diffusion-tight cladding with open sides ^(*) Diffusion-tight cladding with open sides ^(*)

Table 1

^(*) The foam was made by applying a gas diffusion impermeable sealant (aluminum-containing air impervious laminated foil) to the top and bottom surfaces of the foam and leaving the sides open (thickness). This results in a foam where 83% of the foam surfaces are coated with a diffusion-tight sealant.

^(**) Molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ] .

The residual amount of the NaOH compound measured in the aged foam, the measured stabilized aged lambda coefficients, and the measured % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam are shown below:

Molar ratio [X]/[X1] ^(*) Amount of absorber in foam [% (w/w)] Stabilized aged lambda coefficient [mW/m.K] Measured CO ₂ compound (when stabilized and aged) [% (w/w)] Measured physical blowing agent VA (when stabilized and aged) [% (w/w)] % CO ₂ ^(**) (with stabilization and aging) [%] Residual NaOH compound measured in aged foam, [% (w/w)] Comparative example 1 (without absorber) - 0 23.6 2.2 1.32 83% 0 Example 1 (in the presence of an absorber) 7.5:1 7.4 18.6 0.02 1.16 5% 0.7

^(*) The molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ].

^(**) Measured value % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam.

Figure 1 illustrates the lambda coefficient measured at 10° C. for Example 1 and Comparative Example 1 as a function of time (aging at room temperature). The synergistic effect of a CO ₂ scavenger in combination with a physical blowing agent having a lambda coefficient for gas ≤12 mW/m.K at 10° C. (in this case an HCFO blowing agent) under gas diffusion impermeable conditions is surprising and significant. Example 1 has a surprisingly low stabilized thermal conductivity < 19 mW/m.K, while comparative example 1 has a much higher stabilized thermal conductivity at coefficients > 23 mW/m.K.

As can be seen, the effect of the CO ₂ scavenger is complete at the end of 8 weeks of aging, after this period the lambda coefficient for the foam of example 1 stabilizes. To ensure that lambda coefficient stabilization is maintained, the foam must be coated at least partially with a diffusion-tight sealant (aluminium-containing air- and CO2-tight laminated foil) _on the top and bottom surfaces of the foam.

Comparative Example 1 illustrates the insufficiency of using blowing agents having low thermal conductivity under conditions of gas diffusion impermeability to achieve insulating foams having a long-term low lambda coefficient.

2. Production of insulation foam containing PUR polymer using a CO absorber ₂ , blowing agents HCFO, HFO and HFC (examples 1, 2 and 3) and comparative examples 2+3 using a CO absorber ₂ and alternative blowing agents (illustrating the effect of a blowing agent)

Four insulating foams containing polyurethane were made in a closed mold having dimensions of 30 cm (long) by 30 cm (width) by 3 cm (thickness), using an isocyanate index of 123.

Table 2 summarizes the reaction system and the amounts of ingredients used in parts by weight (m. h.) for implementation

1) Example 1 according to the present invention using NaOH as CO ₂ scavenger and HCFO 1233zd blowing agent and

2) Example 2 of the present invention using NaOH as CO ₂ scavenger and Opteon® 1100 HFO blowing agent and

3) Example 3 according to the present invention using NaOH as CO ₂ scavenger and HFC foaming agent Enovate® 245fa,

4) Comparative example 2 using NaOH CO ₂ scavenger and using n-pentane as blowing agent having a gas lambda coefficient >> 12 mW/m.K at 10°C, and

5) Comparative Example 3 using the CO ₂ scavenger NaOH and water as the sole blowing agent.

All foams were produced by applying the same gas diffusion-tight sealant according to the invention (where 83% of the foam surfaces are covered with a gas-diffusion-tight sealant).

reaction system Comparative example 2, m.h. Comparative example 3, m.h. An example of the invention (example 1), m.h. An example of the invention (example 2), m.h. An example of the invention (example 3), m.h. Polyol 1 29.7 29.7 29.7 29.7 29.7 Polyol 2 fifteen fifteen fifteen fifteen fifteen Polyol 3 50.8 50.8 50.8 50.8 50.8 Catalyst 1 1.9 1.9 1.9 1.9 1.9 Catalyst 2 0.5 0.5 0.5 0.5 0.5 Catalyst 3 0.1 0.1 0.1 0.1 0.1 Foam Stabilizer 0.7 0.7 0.7 0.7 0.7 Water 1.3 2.3 1.3 1.3 1.3 Foaming agent HCFO (Solstice® ^1233zd ) 7 Foaming agent HFO (Opteon ^® 1100) 9 Foaming agent n-pentane 3.9 Foaming agent HFC 245fa 7.2 CO ₂ absorber (NaOH beads) 21.3 22.5 21.6 21.7 21.6 Molar ratio [X]/[X1] ^(**) 7.4:1 4.4:1 7.5:1 7.5:1 7.5:1 S5025 162 181 162 162 162 Isocyanate index 123 123 123 123 123 Foam density (kg/m ³ ) 67.6 68.8 71.7 73.1 72.1 Facing Diffusion-tight cladding with open sides ^(*) Diffusion-tight cladding with open sides ^(*) Diffusion-tight cladding with open sides ^(*) Diffusion-tight cladding with open sides ^(*) Diffusion-tight cladding with open sides ^(*)

table 2

^(*) The foam was made by applying a gas diffusion impermeable sealant (aluminum-containing air impermeable laminated foil) to the top and bottom surfaces of the foam and leaving the sides open. This results in a foam where 83% of the foam surfaces are coated with a sealant impervious to gas diffusion.

^(**) Molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ] .

The residual amount of the NaOH compound measured in the aged foam, the measured stabilized aged lambda coefficients, and the measured % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam are shown below:

Molar ratio [X]/[X1] ^(*) Amount of absorber in foam [% (w/w)] Stabilized aged lambda coefficient [mW/m.K] Measured CO ₂ compound (when stabilized and aged) [% (w/w)] Measured physical blowing agent VA (when stabilized and aged) [% (w/w)] % CO ₂ ^(**) (with stabilization and aging) [%] Residual NaOH compound measured in aged foam, [% (w/w)] Example 1 (Solstice LBA) 7.5:1 7.4 18.6 0.02 1.16 5% 0.70 Example 2 (Opteon 1100) 7.5:1 7.4 17.8 0.02 2.61 3% 0.60 Example 3 (HFC 245fa) 7.5:1 7.4 19.3 0.03 1.96 5% 0.90 Comparative Example 2 (n-pentane) 7.4:1 7.4 23.3 0.02 0.7 5% 0.60 Comparative example 3 (foaming by reaction with water) 4.4:1 7.4 28 ^(***) 0.09 0 100% 0.10

^(*) The molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ].

^(**) Measured value % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam.

^(***) at 14 weeks there is no stabilization yet.

Figure 2 illustrates the lambda coefficient measured at 10° C. for Example 1, Example 2, Example 3 and Comparative Examples 2 and 3 as a function of time (aging at room temperature). The synergistic effect of a CO ₂ scavenger in combination with the use of a physical blowing agent having a gas lambda value ≤12 mW/m.K at 10° C. under air diffusion tight conditions is again surprising and significant. The comparative examples illustrate the inadequacy of using a CO ₂ scavenger under gas diffusion impermeability to achieve insulating foams having a long-term low lambda coefficient.

As can be seen, the effect of the CO ₂ scavenger is complete at the end of 8 weeks of aging, after this period the lambda coefficient for foams from examples 1, 2 and 3 stabilizes. To ensure that lambda coefficient stabilization is maintained, the foam must be coated with a gas diffusion-tight (air-tight) sealant on the top and bottom surfaces of the foam.

3. Production of insulation foam containing PIR polymer using a CO absorber ₂ and HCFO Foamer (Example 1) and Comparative Example 4 Excluding Gas Diffusion Impermeability Conditions (Illustration of Foam Sealing Effect)

Two insulating foams containing polyurethane were made in a closed mold measuring 30 cm (long) by 30 cm (width) by 3 cm (thickness) using an isocyanate index of 123.

Table 3 summarizes the reaction system and amounts of ingredients used in parts by weight (m.p.h.) for implementation

1) Example 1 according to the present invention using NaOH as a CO ₂ scavenger and a physical blowing agent having a gas lambda value of ≤12 mW/m.K at 10°C (which in this case is HCFO Solstice® 1233zd blowing agent) in conditions of impermeability for gas diffusion and

2) Comparative Example 4 using NaOH as a CO ₂ scavenger and a physical blowing agent having a gas lambda value of ≤12 mW/m.K at 10°C (which in this case is the blowing agent HCFO 1233zd), but without impermeability conditions for gas diffusion (in the presence of gas-permeable paper lining).

reaction system Comparative example 4, m.h. An example of the invention (example 1), m.h. Polyol 1 29.7 29.7 Polyol 2 fifteen fifteen Polyol 3 50.8 50.8 Catalyst 1 1.9 1.9 Catalyst 2 0.5 0.5 Catalyst 3 0.1 0.1 Foam Stabilizer 0.7 0.7 Water 1.3 1.3 Foaming agent HCFO (Solstice® ^1233zd ) 7 7 CO ₂ absorber (NaOH beads) 21.6 21.6 Molar ratio [X]/[X1] ^(**) 7.5:1 7.5:1 S5025 162 162 Isocyanate index 123 123 Foam density (kg/m ³ ) 70.3 71.7 Facing Gas permeable paper lining Diffusion-tight cladding with open sides ^(*)

Table 3

^(*) The foam was made by applying a gas diffusion impermeable (air impermeable) sealant to the top and bottom surfaces of the foam and leaving the sides open. This results in a foam where 83% of the foam surfaces are covered with a gas diffusion impervious sealant (aluminium-containing air impervious laminated foil).

^(**) The molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the isocyanate present in the formulation used to make the foam, [X ₁ ].

The residual amount of the NaOH compound measured in the aged foam, the measured stabilized aged lambda coefficients, and the measured % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam are shown below:

Molar ratio [X]/[X1] ^(*) Amount of absorber in foam [% (w/w)] Stabilized aged lambda coefficient [mW/m.K] Measured CO ₂ compound (when stabilized and aged) [% (w/w)] Measured physical blowing agent VA (at stabilization and aging) [% (w/w)] % CO ₂ ^(**) (with stabilization and aging) [%] Residual NaOH compound measured in aged foam, [% (w/w)] Comparative Example 4 7.5:1 7.4 21.2 0.07 1.23 fourteen 0.9 Example 1 7.5:1 7.4 18.6 0.02 1.16 5 0.7

^(*) The molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ].

^(**) Measured value % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam.

Figure 3 illustrates the lambda coefficient measured at 10° C. for Example 1 and Comparative Example 4 as a function of time (aging at room temperature). The synergistic effect of the CO ₂ scavenger in combination with the use of a physical HCFO blowing agent and the presence of a sealant is surprising and significant. Example 1 has a surprisingly low stabilized thermal conductivity < 19 mW/mK, while Comparative Example 4 has no stabilized thermal conductivity, on the contrary, the thermal conductivity increases (degrades) over extended periods of time.

As can be seen, the effect of the CO ₂ scavenger is complete at the end of 8 weeks of aging, after this period the lambda coefficient for example 1 stabilizes. To ensure that lambda coefficient stabilization is maintained, the foam must be coated with a gas diffusion-tight (air-tight) sealant on the top and bottom surfaces of the foam.

Comparative Example 4 illustrates the importance of applying a sealant to achieve gas diffusion impermeability conditions according to the invention in achieving insulating foams having a long-term low lambda coefficient.

4. Making insulation foam containing PIR polymer using HCFO as a physical blowing agent and various amounts of CO scavenger ₂ (Illustration of the amount of CO absorbent required ₂ )

Five insulating foams containing polyisocyanurate were made using an isocyanate index of 320.

Table 4 summarizes the reaction system and amounts of ingredients used in parts by weight (m.p.h.) for implementation

1) Comparative example A0 without scavenger and with HCFO Solstice LBA blowing agent and

2) Comparative Example A1 using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [ X ₁ ] 3 : 1 and when using HCFO Solstice LBA foam concentrate and

3) Example A2 using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ] 15 : 1 and when using HCFO Solstice LBA foam concentrate and

4) example A3 according to the invention, using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed as a result of the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain foam, [X ₁ ] 33 : 1 and using HCFO Solstice LBA foam concentrate and

5) example A4 according to the invention, using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain foam, [X ₁ ] 21 : 1 and using HCFO Solstice LBA blowing agent.

All foams were produced in a closed mold measuring 30 cm (length) by 30 cm (width) by 3 cm (thickness) while applying a 100% EVOH-based diffusion-tight sealant according to the invention.

reaction system Comparative example A0, m.h. Comparative example A1, m.h. Example A2, m.h. Example A3, m.h. Example A4, m.h. Polyol 4 80.16 80.16 80.16 80.16 80.16 Flame retardant 1 16 16 16 16 16 Catalyst 2 0.1 0.1 0.1 0.1 0.1 Catalyst 4 1.36 1.36 1.36 1.36 1.36 Catalyst 5 0.45 0.45 0.45 0.45 0.45 Foam Stabilizer 1.6 1.6 1.6 1.6 1.6 Water 0.33 0.33 0.33 0.33 0.33 Foaming agent HCFO (Solstice® ^1233zd ) 32.7 32.7 32.7 32.7 32.7 CO ₂ absorber (NaOH micrograins) 0 2.2 10.9 24.0 15.2 Molar ratio [X]/[X1] ^(**) - 3:1 15:1 33:1 21:1 S2085 170 170 170 170 170 Isocyanate index 320 320 320 320 320 Foam density (kg/m ³ ) 44.7 45.8 46.2 48.2 46.4 Facing Diffusion-tight lining ^(*) Diffusion-tight lining ^(*) Diffusion-tight lining ^(*) Diffusion-tight lining ^(*) Diffusion-tight lining ^(*)

Table 4

^(*) The foam was made by applying a gas diffusion-tight sealant made from EVOH polymer and thus completely encapsulating the foam (100% coverage).

^(**) Molar ratio between the added CO ₂ scavenger [X] and the calculated theoretical molar amount of CO ₂ compound formed from the reaction between the molar amount of water and the molar amount of isocyanate present in the foam [X ₁ ].

The residual amount of the NaOH compound measured in the aged foam, the measured stabilized aged lambda coefficients, and the measured % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam are shown below:

Molar ratio [X]/[X1] ^(*) Amount of absorber in foam [% (w/w)] Stabilized aged lambda coefficient [mW/m.K] Measured CO ₂ compound (when stabilized and aged) [% (w/w)] Measured HFO compound (when stabilized and aged) [% (w/w)] % CO ₂ ^(**) (with stabilization and aging) [%] Residual NaOH compound measured in aged foam, [% (w/w)] Comparative example A0 - 0 19.0 2.72 9.14 47% 0 Comparative example A1 3:1 0.7 18.6 1.78 9.21 36% 0 Example A2 15:1 3.5 17.4 0.30 8.84 9% 0 Example A4 21:1 4.8 16.6 0 8.52 0% 0.2 Example A3 33:1 7.3 16.5 0 8.43 0% 2.7

^(*) The molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ].

^(**) Measured value % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam.

Figure 4 illustrates the lambda coefficient measured at 10°C for examples A2 - A4 and comparative examples A0 - A1 as a function of time (aging at room temperature). The synergistic effect of an optimized amount of CO ₂ scavenger in combination with the use of a physical blowing agent having a lambda coefficient for gas ≤12 mW/m.K at 10° C. (in this case an HCFO blowing agent) under conditions of impermeability to gas diffusion is surprising and significant. Examples A3 and A4 have surprisingly low stabilized thermal conductivity (< 17 mW/m.K), while comparative examples A1 and A0 have much higher stabilized thermal conductivity at coefficients > 18.5 mW/m.K.

As can be seen, the effect of the CO ₂ scavenger is complete at the end of 8 weeks of aging, after this period the lambda coefficient of the foam stabilizes. To ensure that the stabilization of the lambda coefficient is maintained, the foam must be coated with a diffusion-tight sealant (in this case made from EVOH polymer and thus completely encapsulating the foam (100% coverage)).

Comparative example A1 illustrates that the [X]/[X1] 3 : 1 molar ratio is not sufficient to obtain a sufficient reduction in CO ₂ due to aging, for the case of sealing the foam with respect to gas transfer, but not with respect to moisture diffusion, the amount of CO ₂ increases even more . Therefore, a [X]/[X1] molar ratio of much more than 3:1 is required.

Example A2 illustrates the non-detection of residual NaOH compound in the aged foam even at a [X]/[X1] molar ratio of 15:1, which means that all the NaOH compound is consumed in the CO ₂ scavenging process while contributing to the decrease in the lambda coefficient. Therefore, a [X]/[X1] molar ratio of much more than 3:1 is required.

5. Production of insulating foam containing PIR polymer using different amounts of CO scavenger ₂ and cyclopentane as a physical blowing agent (illustration of the amount of CO scavenger required ₂ )

Five insulating foams containing polyisocyanurate were made using an isocyanate index of 320.

Table 5 summarizes the reaction system and the amounts of ingredients used in parts by weight (m.h.) for implementation

1) comparative example B0 without the use of scavenger and using cyclopentane as a physical blowing agent and

2) Comparative Example B1 using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [ X ₁ ] 3 : 1 and when using cyclopentane as a physical blowing agent and

3) example B2 using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ] 15 : 1 and when using cyclopentane as a physical blowing agent and

4) example B3 according to the invention, using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed as a result of the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain foam, [X ₁ ] 33 : 1 and when using cyclopentane as a physical blowing agent.

All foams were produced in a closed mold measuring 30 cm (length) by 30 cm (width) by 3 cm (thickness) while applying a 100% EVOH-based diffusion-tight sealant according to the invention.

reaction system Comparative example B0, m.h. Comparative example B1, m.h. Example B2, m.h. Example B3, m.h. Polyol 4 80.16 80.16 80.16 80.16 Flame retardant 1 16 16 16 16 Catalyst 2 0.1 0.1 0.1 0.1 Catalyst 4 1.36 1.36 1.36 1.36 Catalyst 5 0.45 0.45 0.45 0.45 Foam Stabilizer 1.6 1.6 1.6 1.6 Water 0.33 0.33 0.33 0.33 Foaming agent cyclopentane 17.2 17.2 17.2 17.2 CO ₂ absorber (NaOH micrograins) 0 2.2 10.9 24.0 Molar ratio [X]/[X1] ^(**) - 3:1 15:1 33:1 S2085 170 170 170 170 Isocyanate index 320 320 320 320 Foam density (kg/m ³ ) 45.3 45.3 46.5 48.7 Facing Diffusion-tight lining ^(*) Diffusion-tight lining ^(*) Diffusion-tight lining ^(*) Diffusion-tight lining ^(*)

Table 5

^(*) The foam was made by applying a gas diffusion-tight sealant made from EVOH polymer and thus completely encapsulating the foam (100% coverage).

^(**) Molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ] .

The residual amount of the NaOH compound measured in the aged foam, the measured stabilized aged lambda coefficients, and the measured % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam are shown below:

Molar ratio [X]/[X1] ^(*) Amount of absorber in foam [% (w/w)] Stabilized aged lambda coefficient [mW/m.K] Measured CO ₂ compound (when stabilized and aged) [% (w/w)] Measured cyclopentane (when stabilized and aged) [% (w/w)] % CO ₂ ^(**) (with stabilization and aging) [%] Residual NaOH compound measured in aged foam, [% (w/w)] Comparative example B0 - 0 21.2 2.98 5.05 48% 0 Comparative example B1 3:1 0.7 21.0 2.41 5.1 43% 0 Example B2 15:1 3.7 20.3 0.25 4.92 eight% 0 Example B3 33:1 7.7 19.1 0 4.67 0% 1.75

^(*) The molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ].

^(**) Measured value % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam.

Figure 5 illustrates the lambda coefficient measured at 10° C. for Examples B2 - B3 and Comparative Examples B0 - B1 as a function of time (aging at room temperature). The synergistic effect of an optimized amount of CO ₂ scavenger in combination with the use of a physical blowing agent having a lambda coefficient for gas ≤12 mW/m.K at 10° C. (in this case cyclopentane blowing agent) under conditions of impermeability to gas diffusion is surprising and significant. Example B3 has a surprisingly low stabilized thermal conductivity (approximately 19 mW/m.K), while comparative examples B1 and B0 have a much higher stabilized thermal conductivity at coefficients of approximately 21 mW/m.K.

As can be seen, the effect of the CO ₂ scavenger is complete at the end of 8 weeks of aging, after this period the lambda coefficient of the foam stabilizes. To ensure that lambda coefficient stabilization is maintained, the foam must be coated with a diffusion-tight sealant (in this case, a gas-diffusion-tight sealant made from EVOH polymer and thus completely encapsulating the foam (100% coverage)).

Comparative example B1 illustrates that the [X]/[X1] 3 : 1 molar ratio is insufficient to obtain a sufficient reduction in CO ₂ due to aging, for the case of sealing the foam with respect to gas transfer, but not with respect to moisture diffusion, the amount of CO ₂ increases even more . Therefore, a [X]/[X1] molar ratio of much more than 3:1 is required.

6. Making insulation foam containing PUR polymer using HFO as a physical blowing agent and various amounts of CO scavenger ₂ (Illustration of the amount of CO absorbent required ₂ )

Five insulating foams were made containing polyurethane using an isocyanate index of 123.

Table 6 summarizes the reaction system and amounts of ingredients used in parts by weight (m.h.) for implementation

1) Comparative example D0 without scavenger and HFO Solstice LBA blowing agent and

2) Comparative Example D1 using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the formulation used to obtain the foam, [ X ₁ ] 3 : 1 and when using HCFO Solstice 1233zd foam concentrate and

3) example D2 using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ] 5 : 1 and when using HCFO Solstice 1233zd foam concentrate and

4) example D3 according to the invention, using the molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed as a result of the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain foam, [X ₁ ] 7.5 : 1 and using HCFO Solstice 1233zd foam concentrate.

All foams were produced in a closed mold measuring 30 cm (length) by 30 cm (width) by 3 cm (thickness) while applying a 100% EVOH-based diffusion-tight sealant according to the invention.

reaction system Comparative example D0, m.h. Comparative example D1, m.h. Example D2, m.h. Example D3, m.h. Polyol 1 29.7 29.7 29.7 29.7 Polyol 2 fifteen fifteen fifteen fifteen Polyol 3 50.8 50.8 50.8 50.8 Catalyst 1 1.9 1.9 1.9 1.9 Catalyst 2 0.5 0.5 0.5 0.5 Catalyst 3 0.1 0.1 0.1 0.1 Foam Stabilizer 0.7 0.7 0.7 0.7 Water 1.3 1.3 1.3 1.3 Foaming agent HCFO (Solstice® ^1233zd ) 7 7 7 7 CO ₂ absorber (NaOH micrograins) 0 8.7 14.4 21.7 Molar ratio [X]/[X1] ^(**) - 3:1 5:1 7.5:1 S5025 162 162 162 162 Isocyanate index 123 123 123 123 Foam density (kg/m ³ ) 71.4 71.7 74.0 75.8 Facing Diffusion-tight lining ^(*) Diffusion-tight lining ^(*) Diffusion-tight lining ^(*) Diffusion-tight lining ^(*)

Table 6

^(*) The foam was made by applying a gas diffusion-tight sealant made from EVOH polymer and thus completely encapsulating the foam (100% coverage).

^(**) Molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ] .

The residual amount of the NaOH compound measured in the aged foam, the measured stabilized aged lambda coefficients, and the measured % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam are shown below:

Molar ratio [X]/[X1] ^(*) Amount of absorber in foam [% (w/w)] Stabilized aged lambda coefficient [mW/m.K] Measured CO ₂ compound (when stabilized and aged) [% (w/w)] Measured HFO compound (when stabilized and aged) [% (w/w)] % CO ₂ ^(**) (with stabilization and aging) [%] Residual NaOH compound measured in aged foam, [% (w/w)] Comparative example D0 - 0 23.4 2.86 2.19 79% 0 Comparative example D1 3:1 3.1 22.1 1.12 2.14 61% 0 Example D2 5:1 5.1 20.6 0.23 2.08 25% 0 Example D3 7.5:1 7.5 18.4 0 2.06 0% 0.84

^(*) The molar ratio between the added CO ₂ scavenger [X] and the theoretical calculated molar amount of the CO ₂ compound formed by the reaction between the molar amount of water and the molar amount of isocyanate present in the composition used to obtain the foam, [X ₁ ].

^(**) Measured value % mol. CO ₂ in stabilized aged foam based on the combined moles of CO ₂ and physical blowing agents in stabilized aged foam.

Figure 6 illustrates the lambda coefficient measured at 10°C for examples D2 - D3 and comparative examples D0 - D1 as a function of time (aging at room temperature). The synergistic effect of an optimized amount of CO ₂ scavenger in combination with the use of a physical blowing agent having a lambda coefficient for gas ≤12 mW/m.K at 10° C. (in this case an HCFO blowing agent) under conditions of impermeability to gas diffusion is surprising and significant. Example D3 has a surprisingly low stabilized thermal conductivity (< 19 mW/m.K), while comparative examples A1 and A0 have a much higher stabilized thermal conductivity at coefficients > 22 mW/m.K.

As can be seen, the effect of the CO ₂ scavenger is complete at the end of 8 weeks of aging, after this period the lambda coefficient of the foam stabilizes. To ensure that the stabilization of the lambda coefficient is maintained, the foam must be coated with a diffusion-tight sealant (in this case, a sealant made from an EVOH polymer and thus completely encapsulating the foam (100% coverage)).

Comparative example D1 illustrates that the [X]/[X1] 3 : 1 molar ratio is not sufficient to obtain a sufficient reduction in CO ₂ due to aging, for the case of sealing the foam with respect to gas transfer, but not with respect to moisture diffusion, the amount of CO ₂ increases even more . Therefore, a [X]/[X1] molar ratio of much more than 3:1 is required.

Claims (31)

1. Stabilized aged containing polyisocyanurate (PIR) insulating foam obtained with an isocyanate index of more than 180, and / or containing polyurethane (PUR) insulating foam obtained with an isocyanate index in the range of 123-180, while the foam contains: - at least one physical blowing agent having a lambda coefficient for gas ≤12 mW/m⋅K at 10°C, at least one CO ₂ scavenging compound selected from NaOH and/or KOH and/or reaction products between the CO ₂ scavenging compound and CO ₂ , - a sealant impervious to gas diffusion to avoid air exchange between the foam and the environment, which covers at least 50% of the surfaces of the foam, where the value of % mol. The CO ₂ in the stabilized aged foam is between 0 and 33% based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam, and the amount of residual CO ₂ scavenging compound in the stabilized aged foam is between 0 and 10 % wt. when calculated on the total weight of the stabilized aged foam. 2. The foam according to claim. 1, where the value of mol%. The CO ₂ in the stabilized aged foam is between 0 and 30%, more preferably between 0 and 27%, based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam. 3. Foam according to any one of paragraphs. 1, 2, wherein the amount of residual absorbent compound in the stabilized aged foam is between 0 and 5 wt %, more preferably between 0 and 3 wt %, based on the total weight of the stabilized aged foam. 4. Foam according to any one of paragraphs. 1-3, where the value of mol%. The CO ₂ in the stabilized aged foam is between 0 and 33%, preferably between 0 and 30%, more preferably between 0 and 27%, based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam, and the amount of residual absorbent compound in the stabilized aged foam is in the range between 0 and 5 wt %, more preferably between 0 and 3 wt %, based on the total weight of the stabilized aged foam. 5. Foam according to any one of paragraphs. 1-4, wherein the gas diffusion impervious sealant is selected from gas barrier polymer resin layers such as ethylene-vinyl alcohol (EVOH) copolymer resin layers or multilayers comprising resin layers and combinations thereof, and wherein at least 90%, more preferably 95%, most preferably 90-100%, of the foam surfaces are coated with a gas diffusion-tight sealant. 6. Foam according to any one of paragraphs. 1-4, wherein the gas diffusion impervious sealant is selected from metal foils such as aluminum foil or metal multilayers including aluminum foil, and wherein 50-95%, more preferably 50-85%, most preferably 50-75% , from the surfaces of the foam material is covered with a sealant that is impervious to gas diffusion. 7. Foam according to any one of paragraphs. 1-6, wherein the blowing agents include HFO blowing agents and/or HCFO blowing agents and/or hydrocarbon blowing agents such as cyclopentane having a gas lambda coefficient of ≤12 mW/m⋅K at 10°C, and mixtures thereof. 8. Foam according to any one of paragraphs. 1-7, where blowing agents include cis-1,1,1,4,4,4-hexafluorobuten-2-ene and/or trans-1-chloro-3,3,3-trifluoropropene. 9. Foam according to any one of paragraphs. 1-8, where the blowing agent includes chlorofluorocarbons (CFC) and/or hydrofluorocarbons (HFC) and/or hydrochlorofluorocarbons (HCFC), characterized by a lambda coefficient for gas ≤12 mW/m⋅K at 10°C. 10. The method of obtaining stabilized aged containing polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to any one of paragraphs. 1-9, the method includes: a) combining and/or mixing at least the following ingredients with an isocyanate index in the range of 123-180 for insulating foam containing polyurethane (PUR), and with an isocyanate index of more than 180 for insulating foam containing polyisocyanurate (PIR ), - a polyisocyanate composition containing one or more polyisocyanate compounds, and - at least one catalyst compound suitable for use in the production of foam containing polyisocyanurate (PIR) and/or polyurethane (PUR), and an isocyanate-reactive composition comprising one or more isocyanate-reactive compounds, and - at least one physical blowing agent having a lambda coefficient for gas ≤12 mW/m⋅K at 10°C, and - at least one CO ₂ scavenging compound selected from NaOH and/or KOH, and thereafter b) coating at least 50% of the foam surfaces with a gas diffusion-tight sealant to avoid air exchange between the foam and the environment, and thereafter c) aging the foam to achieve stabilized aged foam, characterized in that the foam is coated with a sealant impervious to diffusion of gas, and the amount of compounds that absorb CO ₂ is such that the value of mol%. The CO ₂ in the stabilized aged foam is between 0 and 33% based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam, and the amount of residual absorbent compound in the stabilized aged foam is between 0 and 10 wt%. when calculated on the total weight of the stabilized aged foam, and where the ratio between the molar amount of added absorbent compound [X] and the theoretical calculated molar amount of CO ₂ [X1] formed as a result of the reaction between the molar amount of water and the isocyanate present in the composition used for foam, [X]/[X1] is more than 3. 11. The method according to p. 10, where the value of mol%. The CO ₂ in the stabilized aged foam is between 0 and 33%, preferably between 0 and 30%, more preferably between 0 and 27%, based on the combined moles of CO ₂ and physical blowing agents in the stabilized aged foam and the amount of residual compound , absorbing CO ₂ in the stabilized aged foam is in the range between 0 and 5 wt. -%, more preferably between 0 and 3 wt. -%, based on the total weight of the stabilized aged foam. 12. The method according to any one of paragraphs. 10, 11, wherein the foam is a polyisocyanurate (PIR) insulating foam and the process is carried out at an isocyanate index greater than 180, more preferably an isocyanate index greater than 250, and the catalyst compound is selected from at least one trimerization catalyst, and the insulation foam is a polyisocyanurate (PIR)-containing foam. 13. The method according to any one of paragraphs. 10-12, wherein the foam is a polyisocyanurate (PIR) insulating foam and the process is carried out at an isocyanate index of more than 180, more preferably an isocyanate index of more than 250, and where the ratio between the molar amount of added absorbent compound [X ] and the theoretical calculated molar amount of CO ₂ [X1] formed as a result of the reaction between the molar amount of water and the isocyanate present in the formulation used to obtain the foam, [X]/[X1] is more than 6, preferably more than 10, more preferably more than 15. 14. The method according to any one of paragraphs. 10-13, where the polyisocyanate compounds are selected from toluene diisocyanate, methylene diphenyl diisocyanate or a polyisocyanate composition containing methylene diphenyl diisocyanate, or a mixture of such polyisocyanates. 15. The method according to any one of paragraphs. 10-14, wherein the one or more isocyanate-reactive compounds include polyols and polyol blends having average hydroxyl numbers ranging from 50 to 1000, especially from 150 to 700, mg KOH/g and hydroxyl functionalities of range from 2 to 8, especially from 3 to 8. 16. The method according to any one of paragraphs. 10-15, where the blowing agent is present in an amount in the range from 1 to 60 wt. hours, preferably from 2 to 45 wt. hours, when calculated per 100 wt. including compounds reactive with respect to isocyanate. 17. The method according to any one of paragraphs. 10-16, further comprising, in addition to blowing agents having a lambda coefficient for gas ≤12 mW/m⋅K at 10°C, additional blowing agents having a lambda coefficient for gas > 12 mW/m⋅K at 10°C, and where the ratio between blowing agents having a lambda coefficient for gas ≤12 mW/m⋅K at 10°C and additional blowing agents corresponds to a weight ratio in the range from 95/5 up to 5/95 when calculating the total mass of all blowing agents. 18. Use containing polyisocyanurate (PIR) and/or polyurethane (PUR) insulating foam according to any one of paragraphs. 1-9 for thermal insulation and/or insulating panels.

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