EP2970711A1

EP2970711A1 - Use of polyesters having inherent flame protection in adhesives and sealants

Info

Publication number: EP2970711A1
Application number: EP14708855.3A
Authority: EP
Inventors: Christina DIEHL; Gabriele Brenner; Bernhard Schleimer
Original assignee: Evonik Degussa GmbH
Current assignee: Evonik Operations GmbH
Priority date: 2013-03-15
Filing date: 2014-03-06
Publication date: 2016-01-20
Also published as: BR112015022139A2; KR20150132290A; CN105102557B; US9840581B2; US20160032045A1; CN105102557A; DE102013204550A1; MY172773A; WO2014139858A1; JP2016518466A

Abstract

The invention relates to the use of polyesters having inherent flame protection as or in adhesives, sealants, and coatings, to polyesters having inherent flame protection, and to methods for the production thereof.

Description

Use of Polvestern with inherent flame retardancy in adhesive and

sealants

The present invention relates to the use of inherent flame retardant polyesters as or in adhesives, sealants and coatings, inherent flame retardant polyesters and methods for their preparation.

Hotmelt adhesives represent an important class of adhesives for many applications, for example in the automotive industry, furniture manufacturing or textile bonding. They are solid at room temperature and are melted by heating and applied to the substrate at elevated temperature. Upon cooling, they solidify again, thus ensuring a firm bond. A subgroup of

Hotmelt adhesives are reactive hotmelt adhesives that additionally crosslink after application and thereby cure irreversibly. These include, for example, moisture-curing hot melt adhesives, which crosslink by reaction with atmospheric moisture.

For many applications, especially in the public sector, a sufficient flame retardancy is not only the substrates but also the adhesive bond

desirable. In order to slow or even completely prevent combustion, flame retardants are usually used as the formulation component. In addition to mineral substances, for example aluminum hydroxide or antimony oxide, organic flame retardants, such as halogen-containing, and due to the lower toxicity increasingly phosphorus-containing substances are used.

The application EP 1975217 describes flame-retardant adhesive and sealants which contain a mono- or diphosphinic acid salt as flame retardant. However, the addition of a flame retardant generally has a detrimental effect on the adhesion properties of an adhesive formulation. Overall, the bonding is thus significantly weakened by the use of an additive flame retardant.

Object of the present invention is to provide an alternative solution for introducing a flame retardant in adhesives or sealants, not to a Deterioration of the adhesive or sealing properties leads.

This object is achieved by the use of flame-retardant polyester as or in adhesives, sealants and coatings.

Accordingly, a first object of the present invention is the use of polyesters based on di- or polycarboxylic acids and di- or polyols as adhesives or sealants or as an ingredient in adhesives, sealants and

Coatings, where the polyesters contain at least one diol of the formula (I)

O

OH A O- O B OH

R (l), wherein R is a saturated linear or branched alkyl radical having 1 to 10 carbon atoms and A and B may be identical or different and are selected from saturated linear or branched alkylene groups having 1 to 10 carbon atoms or from mono - or polyalkylene glycol groups.

R is a saturated linear or branched alkyl radical having 1 to 10 C atoms, in particular having 1 to 3 C atoms. Examples of preferred alkyl radicals are methyl and ethyl groups.

A and B can be identical or different and can be selected from saturated linear or branched alkylene groups having 1 to 10 carbon atoms or from mono- or polyalkylene glycol groups.

In the case of alkylene groups are alkylene groups having 1 to 10 carbon atoms, preferably having 1 to 3 carbon atoms. Examples more preferred

Alkylene groups are ethylene and propylene groups.

In the case of mono- or polyalkylene glycol groups, these are preferably selected from ethylene glycol groups of the general formula -CH ₂ -CH ₂ (-O-CH ₂ -CH ₂ ) n- or Propylene glycol groups of the formula -CH 2 -CH (CH ₃ ) (- O-CH 2 -CH (CH ₃ )) n- with n an integer between 1 and 10. Very particularly preferred are di- and

Trialkylene glycol groups (n = 1 or n = 2). The diol of the formula (I) used is particularly preferably methylbis [2- (2-hydroxyethoxy) ethyl] phosphonic acid ester (n = 1).

With regard to the other di- or polycarboxylic acids and diols or polyols of the polyester, there are basically no restrictions, and basically all mixing ratios can occur. The selection depends on the

desired physical properties of the polyester. These may be amorphous, liquid or (partially) crystalline at room temperature.

Examples of suitable di- or polycarboxylic acids and their derivatives are both aromatic compounds such as dimethyl terephthalate, terephthalic acid,

Isophthalic acid, naphthalenedicarboxylic acid and phthalic anhydride. Further

Examples are cyclic and linear aliphatic dicarboxylic acids such as

Cyclohexanedicarboxylic acid, hexahydrophthalic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid, 1, 12-dodecanedicarboxylic acid and

1, 14-Tetradecandicarbonsäure and their diesters and anhydrides.

For the preparation of liquid or (partially) crystalline polyesters, preference is given to using aliphatic dicarboxylic acids as di- or polycarboxylic acids.

Most preferably, the polyester contains adipic acid and sebacic acid. The diols or polyols contained in the polyesters used according to the invention may contain, in addition to the diol of the formula (I), further diols or polyols. The diols or polyols may be aliphatic or cycloaliphatic diols, such as 1, 2-ethanediol, 1, 3-propanediol, 1, 2-propanediol,

1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 9-nonanediol, 1, 12-dodecanediol, methylpropanediol, diclidol, cyclohexanedimethanol or neopentyl glycol act. Furthermore, it may be oligomeric diols such as oligoethylene glycol,

Oligopropylene glycol and other oligoether act.

Also polyols with more than two functional groups, such as

Trimethylolpropane, pentaerythrol or glycerol can be used. In addition, lactones and hydroxycarboxylic acids can be used as mono-, di- or polyols.

In addition to the diol of the formula (I), preference is given to containing no further diols or polyols with ether groups, for example oligoethylene glycol, oligopropylene glycol and other oligoethers in the polyester used according to the invention. A particularly preferred polyester consists of adipic acid, hexanediol-1, 6,

Neopentyl glycol and the diol of formula (I). The proportion of the diol of the formula (I) in the polyester is arbitrary. However, there usually exists an optimum level at which the phosphorus content is sufficiently high for a flame retardant effect in the adhesive or sealant, but at the same time, the physical properties of the polyester are not excessively affected. The phosphorus content of the polyester is therefore preferably 100 to 20,000 ppm, most preferably 5,000 to 15,000 ppm. This corresponds to a proportion of the diol of the formula (I) of from 0.1 to 15 mol%, particularly preferably from 4 to 12 mol%, based on the sum of the diols or polyols of the polyester used according to the invention. The synthesis of the polyester is preferably carried out via a melt condensation.

For this purpose, the above-mentioned di- and / or polycarboxylic acids and di- and / or polyols in an equivalent ratio of hydroxyl to carboxyl groups of 0.5 to 1.5, preferably 1 .0 to 1.3, submitted and melted. The polycondensation takes place in the melt at temperatures between 150 and 280 ° C within 3 to 30 h. First, a large part of the released amount of water is at

Distilled off normal pressure. In the course of the remaining reaction water and volatile diols is split off until the desired molecular weight is reached. Optionally, this can be facilitated by reduced pressure, enlargement of the surface or by passing an inert gas stream. The reaction may additionally be accelerated by adding an entraining agent and / or a catalyst before or during the reaction. Suitable entrainers are, for example, toluene and xylenes. Typical catalysts are organotitanium or tin compounds such as tetrabutyl titanate or dibutyltin oxide. Also conceivable are catalysts which are based on other metals such. As zinc or antimony based and metal-free esterification catalysts. Furthermore are Other additives and driving aids such as antioxidants or color stabilizers possible.

The polyesters used according to the invention have hydroxyl and / or

Carboxyl end groups, preferably the functionality is between 1, 0 and 3.0.

The concentration of hydroxyl end groups, determined by titrimetry according to DIN 53240-2, is between 0 and 200, preferably between 5 and 50 mg KOH / g. The concentration of acid end groups, determined according to DIN EN ISO 21 14, is between 0 and 50 mg KOH / g, but preferably below 2 mg KOH / g.

The number-average molecular weight of the polyester used according to the invention is 500-30,000 g / mol, preferably 1,000-20,000 g / mol. It is determined according to DIN 55672-1 by means of gel permeation chromatography in tetrahydrofuran as eluent and polystyrene for calibration.

The glass transition temperature of the polyesters of the invention is in the range of -80 ° C to 100 ° C, preferably between -50 ° C and + 50 ° C. In addition, one or more melting and recrystallization points may occur. The determination of the thermal properties is carried out according to the DSC method according to DIN 53765.

The inventive use of polyesters containing diols of the formula (I), a flame retardant is introduced into the adhesives and sealants, without the properties of the adhesive bonds or the sealing properties are impaired. This is achieved in that the polyester used according to the invention contains a phosphorus-containing comonomer, which acts as an inherent flame retardant, so that the subsequent addition of the adhesives or sealants with

Flame retardants can be omitted. As a reactive instead of an additive

Flame retardant is used, the adhesion properties of

resulting adhesive formulation is not adversely affected compared to a non-flame retardant formulation. The covalent linkage of the flame retardant within the polyester also ensures that they are homogeneously distributed in the adhesives or sealants and can not migrate, that is can not be washed out. Thus, a long-lasting Flame protection ensured.

The use according to the invention may be any kind of adhesives known to the person skilled in the art with regard to the adhesives. In particular, the adhesives are hot-melt adhesives.

In a preferred embodiment of the present invention, the hot melt adhesives are thermoplastic hot melt adhesives that cure purely physically.

When used in thermoplastic hot melt adhesives that is

number average molecular weight in particular 10,000 - 30,000 g / mol, preferably 10,000 - 20,000 g / mol.

The proportion of the diol of the formula (I) in these cases is preferably 4 to 12 mol%, based on the sum of the diols or polyols of the polyester used according to the invention and mixtures thereof. These amounts of the diol of formula (I) are already sufficient to provide effective flame retardancy

guarantee. The other monomers are arbitrary and depend on the desired physical properties of the polyester. In a further preferred embodiment of the present invention, the hot melt adhesives are reactive hotmelts (RHM), which additionally crosslink chemically, with moisture-curing hotmelt adhesives being particularly preferred. When used in reactive hotmelt adhesives, the numbers are medium

Molecular weight of the polyester used according to the invention preferably 500 -

10000 g / mol, particularly preferably 2000-8000 g / mol.

The proportion of the diol of the formula (I) is arbitrary and is preferably 4 to

12 mol%, based on the sum of the di- or polyols of the polyester used in the invention and mixtures thereof. This ensures that also in the present in reactive hot melt adhesives additives and

Formulating ingredients, the amount of the diol of formula (I) is sufficient to ensure effective flame retardancy. A preferred example of reactive hot melt adhesives are moisture-curing Melt adhesives. As a rule, these are reaction products of the polyesters used according to the invention with an excess of polyisocyanates which after application with moisture, for. As humidity, react and lead to additional networking.

The adhesives can be produced in a simple manner. If, according to one of the preferred embodiments, further components are used with the polyester used according to the invention, the adhesive is produced in the simplest case by mixing the mixture and the additional components. The mixing can be carried out with or without solvent, preferably without solvent and most preferably in the melt. The mixing can be carried out, for example, in a stirred tank, a kneader or an extruder. The melting temperature depends on the viscosity of the constituents. It is usually in a range of 80 to 180 ° C.

The moisture-curing hot melt adhesives described above can be prepared at temperatures between 50 and 130 ° C depending on the viscosity of the respective formulation. In a several hours tempering of the

Adhesive for further processing is recommended a storage temperature of <100 ° C, since at higher temperatures as side reaction, the formation of carbodiimides occurs. This leads to a significant increase in viscosity and a strong foaming of the formulation.

In particular, the moisture-crosslinking hot melt adhesives additionally contain isocyanates and / or polyisocyanates. In the adhesives, the OH: NCO ratio of polyester to isocyanate and / or polyisocyanate is generally 1: 1, 2 to 1: 3, preferably 1: 1, 5 to 1: 2.5.

The polyisocyanates may be difunctional and / or multifunctional, aromatic, aliphatic or / and cycloaliphatic isocyanates and carbodiimide-modified isocyanates or isocyanate-terminated prepolymers. Aromatic polyisocyanates are particularly preferred. Examples of polyisocyanates are 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, toluene diisocyanate isomers, isophorone diisocyanate, hexamethylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, and mixtures thereof. In particular, it is 4,4'-diphenylmethane diisocyanate and Mixtures of 4,4'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate.

In a further embodiment, the moisture-crosslinking hotmelt adhesives additionally comprise organosilanes in addition to or instead of the polyisocyanates. The functionalization of the polyesters used according to the invention can be carried out by a stepwise reaction with polyisocyanates to isocyanate-terminated prepolymers and subsequent reaction with organosilanes or by reaction with an adduct of polyisocyanates and organosilanes. In the simplest case, the reaction of the polyesters with an isocyanatoalkylsilane takes place in an OH / NCO ratio of 1: 1 to 1: 1, 5.

Examples of organosilanes are aminopropyltrimethoxysilane,

Aminopropyltriethoxysilane, N-methyl-aminopropyltrimethoxysilane, N-cyclohexylaminopropyltrimethoxysilane, N-phenyl-aminopropyltrimethoxysilane

Mercaptopropyltrimethoxysilane, mercaptotriethoxysilane.

In the reactive hot melt adhesives, the proportion of the polyesters used according to the invention is 1-99% by weight, and preferably 5-85% by weight.

In preferred embodiments, in addition to the polyesters used according to the invention, other polyols are present in the reactive hotmelt adhesives, such as polyesterpolyols, polyetherpolyols and any desired hydroxyl-functional components.

The admixed polyester polyols may be liquid or solid, amorphous or (partly) crystalline polyesters of any structure having number average molecular weights (M _n ) between 1000 g / mol and 30 000 g / mol, preferably between 2000 g / mol and 10000 g / mol (calculated from the hydroxyl number), with linear polyester polyols being preferably used. The admixed polyether polyols are polyether di- and triols. Examples include homopolymers and copolymers of ethylene glycol, propylene glycol and 1,4-butanediol. The number-average molecular weight (M _n ) of the mixed polyether polyols should be in a range of 200 g / mol to 10,000 g / mol, preferably, between 400 g / mol and 6000 g / mol. Examples of any hydroxy-functional components are functionalized (H acide), thermoplastic polyurethanes (TPU) and / or polyacrylates and / or ethylene-vinyl acetate copolymers (EVA).

In addition, the hot melt adhesives may contain other additives. These additives may be: non-functionalized polymers, e.g. B. thermoplastic

Polyurethanes (TPU) and / or polyacrylates and / or ethylene-vinyl acetate copolymers (EVA); Pigments or fillers, eg. Talc, silica, titania,

Barium sulfate, calcium carbonate, carbon black or colored pigments, external

Flame retardants; Tackifier, like. z. For example, rosin resins, hydrocarbon resins, phenolic resins, hydrolysis stabilizers and anti-aging and auxiliary agents

Adhesives, sealants and coatings comprising polyesters based on di- or polycarboxylic acids and diols or polyols, where the polyesters comprise at least one diol of the formula (I)

O

OH- A- 0- 0- B- OH

(I)

wherein R is a saturated linear or branched alkyl radical having 1 to 10 carbon atoms and A and B may be identical or different and are selected from saturated linear or branched alkylene groups having 1 10 C atoms or from mono- or polyalkylene glycol groups also

Subject of the present invention. We described above are preferably hot melt adhesives, and more preferably around

Moisture-curing hotmelt adhesives. The adhesives of the invention are particularly suitable for the production of bonds. In particular, the hot melt adhesives of the invention are suitable for bonding a variety of substrates, in particular for bonding metallic substrates, wood, textiles and very particularly for bonding various plastics. The type and extent of the bond are not limited.

The bonds are preferably adhesions in the wood and furniture industry (for example Montageverklebung as well as the lamination and lamination of decorative films of fiberboard, production of sandwich composites for the production of lightweight panels), in the automotive sector (for example

Retainerverklebungen as well as the lamination and lamination of films and textiles on door side parts and headliner, the seat manufacturing), in the

Construction industry, shoe industry and textile industry as well as in window construction (for example, for profile wrapping). Furthermore, the adhesives according to the invention are suitable in the packaging industry and as sealants and as coating materials. A further subject of the present invention are polyesters based on dicarboxylic polycarboxylic acids and diols or polyols which do not contain an ether group, characterized in that the polyesters contain at least one diol of the formula (I)

O

OH A O- 0 B OH

R (l), wherein R is a saturated linear or branched alkyl radical having 1 to 10 carbon atoms and A and B may be identical or different and are selected from saturated linear or branched alkylene groups having 1 to 10 carbon atoms or from mono - or polyalkylene glycol groups. It is essential that, in addition to the diol of the formula (I), no further diols or polyols having ether groups are contained in the polyester according to the invention.

In the case of alkylene groups are alkylene groups having 1 to 10

C atoms, preferably having 1 to 3 carbon atoms. Examples more preferred Alkylene groups are ethylene and propylene groups.

In the case of the mono- or polyalkylene glycol groups, these are preferably selected from ethylene glycol groups of the general formula -CH ₂ -CH ₂ (-O-CH ₂ -CH ₂ ) n or propylene glycol groups of the formula -CH ₂ -CH (CH 3) (- O-CH ₂ -CH ( CH ₃ )) n- with n an integer between 1 and 4. Very particularly preferred are di- and

Trialkylene glycol groups (n = 1 or n = 2).

The diol of the formula (I) used is particularly preferably methylbis [2- (2-hydroxyethoxy) ethyl] phosphonic acid ester (n = 1).

In the polyesters according to the invention, in addition to the diol of the formula (I), further mono-, di- or polyols may be present. Suitable are all aliphatic or cycloaliphatic diols which contain no ether group. However, unsuitable are ether-group-containing aliphatic or cycloaliphatic diols. These include, for example, diethylene glycol, dipropylene glycol, triethylene glycol and oligomeric diols, especially oligoethylene glycol, oligopropylene glycol and other oligoethers. These diols show in the presence of a diol of the formula (I) over the non-ether-containing diols a prolonged reaction time during the

Polycondensation. Another disadvantage of the low molecular weight ether group-containing aliphatic or cycloaliphatic diols are side reactions that occur during the polycondensation in melt. For example, it tends

Diethylene glycol, especially in the presence of phosphorus-containing compounds for cyclization to the highly volatile dioxane.

Otherwise, all non-ether group-containing aliphatic diols are suitable. These include, for example, 1, 2-ethanediol, 1, 3-propanediol, 1, 2-propanediol,

1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 9-nonanediol, 1, 12-dodecanediol, methylpropanediol, diclidol, cyclohexanedimethanol or neopentyl glycol.

Also polyols with more than two functional groups, such as

Trimethylolpropane, pentaerythrol or glycerol can be used.

In addition, lactones and hydroxycarboxylic acids can be used as mono-, di- or polyols.

In principle, there are no restrictions with regard to the di- or polycarboxylic acids used, and basically all mixing ratios can be used occur.

Examples of suitable di- or polycarboxylic acids and derivatives thereof are aromatic compounds such as dimethyl terephthalate, terephthalic acid,

Isophthalic acid, naphthalenedicarboxylic acid and phthalic anhydride. Further

Examples are cyclic and linear aliphatic dicarboxylic acids such as

1, 14-Tetradecandicarbonsäure and their diesters and anhydrides.

Preferably, aliphatic dicarboxylic acids such as adipic acid and / or sebacic acid are used as di- or polycarboxylic acids.

A particularly preferred polyester consists of adipic acid, hexanediol-1, 6, neopentyl glycol and the diol of the formula (I).

The application DE 2646218 also describes phosphorus-containing polyesters. The phosphorus-containing diol is based on 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide (DOP), which reacts with aromatic dicarboxylic acids and other diols

flame-retardant polyesters copolymerize. Find these polyesters

Use in refractory fibers, films or moldings. The good compatibility of the reactive flame retardant with the polyester is based on the chemically similar structure of the biphenyl derivative DOP with aromatic dicarboxylic acids.

In contrast, the present invention relates to polyesters which are preferred in

Hot melt adhesives are used. For use in hot melt adhesives, the physical properties of the polyesters are of great importance. However, when using the sterically demanding DOP-based diol, the desired polyester properties, such as low viscosities, high crystallinities or high UV stability, often can not be adjusted.

Another disadvantage of DOP-based reactive flame retardants relates to use in reactive hot melt adhesives. These are melted by the reaction of hydroxyl-terminated polyesters with polyisocyanates

synthesized. It is known that pentavalent phosphorus compounds catalyze the reaction of polyisocyanates to carbodiimides. That in this reaction released carbon dioxide leads to a strong foaming of the formulation. In addition, this undesired side reaction leads to an intense orange-red coloration and the formulation already crosslinks during the

Adhesive synthesis.

The catalytic activity of the phosphorus compounds decreases with increasing number of phosphorus-bound oxygen atoms. The side reaction to carbodiimide is thus more pronounced in phosphinates such as the DOP-based diol than in

Phosphonates, such as the diol of formula (I). Thus one observes in a reactive hotmelt formulation containing a polyester from the DOP-based

Phosphinate at a temperature of 80 ° C and exclusion of moisture after 24 h a pronounced cross-linking with foaming. In contrast, formulations based on the polyester of the present invention are stable at the same phosphorus content and under the same conditions and thus easier to handle.

Another advantage of the phosphorus-containing diol according to formula (I) is that, compared with the already known DOP-based diol, a significantly reduced phosphorus content is sufficient to achieve adequate flame retardancy in the adhesive or sealant.

DE 2900686 describes phosphorus-containing polyesters as Egalisierungshilfsmittel. The described polyesters contain, in addition to the diol of the formula (I), preferably

Ether-group-containing diols. They are therefore soluble in water and thus for the

Application as an adhesive unsuitable for the production of durable materials.

Water-soluble means that 20 percent and neutralized with NaOH aqueous solutions of the described polyester have no turbidity.

In contrast, the polyesters according to the invention are not soluble in water, since apart from the diol of the formula (I), no further ether-containing diols are used. This makes them more suitable for use in hot melt adhesives.

The polyesters according to the invention overcome the above-mentioned disadvantages of the prior art and are therefore particularly suitable as or in adhesives, in particular in hotmelt adhesives, with reactive hotmelt adhesives being particularly preferred. Even without further statements, it is assumed that a person skilled in the art can use the above description to the greatest extent. The preferred ones

Embodiments and examples are therefore to be considered as merely descriptive, in no way limiting, disclosure.

Hereinafter, the present invention will be explained in more detail by way of examples. Alternative embodiments of the present invention are obtainable in an analogous manner.

Examples:

Example 1 (not according to the invention)

Production of polyester P1:

951 g of adipic acid (6.51 mol) are melted together with 378 g of neopentyl glycol and 429 g of 1,6-hexanediol (3.63 mol in each case) in a flask with distillation head under nitrogen. At a temperature of 240 ° C, the majority of the resulting water of reaction is distilled off within about four to six hours. Subsequently, 0.15 g (0.01% by weight) of a

Titanium catalyst added and the pressure in the apparatus gradually reduced to 10 mbar. After reaching the desired hydroxyl and acid number range, the reaction is complete.

The polyester P1 has a hydroxyl value of 40 mg KOH / g, measured according to DIN 53240-2 and an acid number of 1 mg KOH / g, measured according to DIN EN ISO 21 14, on.

Example 2 (according to the invention)

Production of polyester 2:

913 g of adipic acid (6.25 mol) are melted together with 349 g of neopentyl glycol and 396 g of 1,6-hexanediol (3.36 mol in each case) in a flask with distillation head under nitrogen. As an additional comonomer, 109 g (0.43 mol) of Exolit OP 560 (from Clariant, according to formula I with R = CH ₃ , A, B = oligoethylene glycol) are added. This corresponds to a phosphorus content of 0.9 wt .-% based on the polyester. The reaction procedure is analogous to that of Example 1. After reaching the desired hydroxyl and acid number range, the reaction is complete.

The incorporation of the reactive flame retardant in the polyester chain can be detected by ³¹ P phosphor NMR. The signal at 33 ppm breaks down due to the covalent bond to the polyester and is slightly upfield shifted.

The polyester P2 has a hydroxyl number of 40 mg KOH / g, measured according to DIN 53240-2 and an acid number of 1 mg KOH / g, measured according to DIN EN ISO 21 14, on. Adhesive Application:

Production of moisture-curing hotmelt adhesives

RHM example 1 (not according to the invention)

250 g of the polyester P1 are melted in a 500 ml flat-bottomed flask and dried at 130 ° C. under reduced pressure. Thereafter, 49 g of 4,4'-diphenylmethane diisocyanate (MDI), which corresponds to an OH / NCO ratio of 1 / 2.2, was added and rapidly homogenized. For complete reaction of the reactants is stirred for 45 minutes at 130 ° C under a protective gas atmosphere. Subsequently, the moisture-curing hot melt adhesive is filled.

RHM example 2 (not according to the invention)

250 g of polyester P1 are melted in a 500 ml flat-bottomed flask.

After addition of 34 g of bisphenol A bis-diphenyl phosphate, the mixture is dried at 130 ° C in a vacuum. Thereafter, 49 g of 4,4'-diphenylmethane diisocyanate (MDI), which corresponds to an OH / NCO ratio of 1 / 2.2, added and rapidly homogenized. To complete the reaction of the reactants

Stirred for 45 minutes at 130 ° C under a protective gas atmosphere. Subsequently, the moisture-curing hot melt adhesive is filled.

By adding a phosphorus-containing additive flame retardant, for example

Bisphenol A bisdiphenyl phosphate, a phosphorus content of 1 wt .-% in the

Formulation to be discontinued.

RHM example 3 (according to the invention)

The preparation is analogous to RHM Example 1 with polyester 2 instead of polyester. 1

Characterization: a) Flame retardancy:

The flame retardant properties are determined according to the test standard UL 94 on test bars from a cured 0.5-1 mm thick RHM film. The curing took place within seven days at 20 ° C and 65% relative humidity in a climatic chamber. Results:

RHM 1 has no flame retardancy.

Dripping burning particles ignite an underneath cotton sample corresponding to vertical flame retardant category V-2.

RHM 2 and RHM 3 are the least flammable and have the highest

Category V-0 on.

b) adhesive properties:

The determination of the adhesive properties on various substrates was carried out according to the method DIN EN 1465 after a curing time of seven days at 20 ° C and 65% relative humidity.

Table 1: Tensile shear strength in N / mm ²

c) migration resistance:

To determine the migration resistance, the percentage mass loss after extraction of the cured reactive hot melt adhesive in boiling acetone was determined after eleven hours.

RHM1 has a mass loss of 1 1%, RHM 2 of 22% and RHM 3 of 13%.

The examples show that the addition of a phosphorus-containing additive flame retardant, the flame retardant compared to a formulation without

Flame retardant is improved. However, the deteriorate

Adhesive properties to various substrates drastically. The higher mass loss illustrates that the additive flame retardant from the adhesive is washed out and can migrate.

The use of polyesters with inherent flame retardancy in hot melt adhesives ensures adequate flame retardance as well as adhesive properties comparable with conventional, flameproof formulations. Of the

Mass loss is also comparable. This shows that the reactive

Flame retardant is covalently bound to the polyester chains and can not migrate.

Claims

claims:

1 . Use of polyesters based on di- or polycarboxylic acids and di- or polyols as adhesives or sealants or as an ingredient in adhesives,

Sealants or coatings, characterized in that the polyesters at least one

Diol of the formula (I) o

OH- A- 0- 0- B- OH

R (i)

wherein R is a saturated linear or branched alkyl radical having 1 to 10 carbon atoms and A and B may be identical or different and are selected from saturated linear or branched alkylene groups having 1 to 10 carbon atoms or from mono- or polyalkylene glycol groups.

2. Use according to claim 1, characterized in that it is the adhesives to hot melt adhesives.

3. Use according to claim 2, characterized in that it is reactive hot melt adhesives in the hot melt adhesives.

4. Use according to one or more of claims 1 to 3, characterized

in that the mono- or polyalkylene glycol groups are selected from ethylene glycol groups of the general formula -CH ₂ -CH ₂ (-O-CH ₂ -CH ₂ ) n or propylene glycol groups of the formula -CH ₂ -CHCH 3 (-O-CH ₂ -CHCH ₃ ) n- with n an integer between 1 and 10.

5. Use according to one or more of claims 1 to 4, characterized

in that in addition to the diol of the formula (I) no further diols or polyols having ether groups are contained in the polyester. Use according to one or more of claims 1 to 5, characterized in that the polyester of adipic acid, hexanediol-1, 6,

Neopentyl glycol and the diol of the formula (I).

Use according to one or more of Claims 1 to 5, characterized in that the diol of the formula (I) used is methylbis [2- (2-hydroxyethoxy) ethyl] phosphonic acid ester.

Adhesives, sealants and coatings containing polyesters based on and / or polycarboxylic acids and di- and / or polyols, characterized

in that the polyesters contain at least one diol of the formula (I)

O

OH- ^■ A- 0- 0- ^■ B- ^■ OH

(I)

9. Adhesives according to claim 8, characterized in that the adhesives are hotmelt adhesives.

10. Adhesives according to claim 9, characterized in that the hot melt adhesives are reactive hot melt adhesives.

1 1. Polyesters based on di- and / or polycarboxylic acids and di- and / or

Polyols containing no ether groups, characterized in that the polyesters contain at least one diol of the formula (I) O

OH A O- ^■ 0 B OH

(I)

Polyester according to claim 1 1, characterized in that the mono- or polyalkylene glycol groups are selected from ethylene glycol groups of the general formula -CH ₂ -CH ₂ (-O-CI-12-CI-12) n- or propylene glycol groups of the formula -CH 2 -CHCH ₃ (-O-CH 2 -CHCH ₃ ) _n - with n an integer between 1 and 10.

A polyester according to claim 11 or 12, characterized in that the diol of the formula (I) used is methylbis [2- (2-hydroxyethoxy) ethyl] phosphonic acid ester.

Polyester according to one or more of claims 1 1 to 13, characterized in that the polyester of adipic acid, hexanediol-1, 6,

Neopentyl glycol and the diol of the formula (I).