RU2798167C2 - Compositions containing polymers based on carbodiimides, epoxies and polyesters, their preparation and application - Google Patents

Abstract

FIELD: chemical industry.

SUBSTANCE: group of inventions relates to a composition containing polymers based on carbodiimides, epoxides and polyesters, their production and use for hydrolysis inhibition. Described is a composition for obtaining moulded articles containing: (a) 0.2-2 wt.% of at least one aromatic carbodiimide; (b) 0.05-4 wt.% of at least one epoxide; and (c) 94-99.75 wt.% of at least one polyester thermoplastic polymer. At the same time, at least one aromatic carbodiimide is a carbodiimide of the formula

, where R¹ is NHCOOR⁵, R⁵ is C₁-C₂₂-alkyl, C₆-C₁₂-cycloalkyl, C₆-C₁₈-aryl or C₇-C₁₈-aralkyl radical, and unsaturated alkyl a radical having 2-22 carbon atoms, preferably 12-20, particularly preferably 16-18 carbon atoms, or an alkoxypolyoxyalkylene radical, and R⁶, R⁷ and R⁸ are each independently methyl or ethyl, where each benzene ring bears only one a methyl group and n has a value from 1 to 10. Epoxide is a compound

where a is between 0 and 10, where a is the average or

where R⁹, R¹⁰ are H, C_1-C₈-alkyl, R¹¹ is C_1-C₈-alkyl, x, y are 1-20 and z is 2-20, and R* is H, C_1-C₈-alkyl. Also described is a method for obtaining the composition, the finished product and the use of the composition to obtain finished products by extrusion.

EFFECT: providing compositions for moulded products that are resistant to hydrolysis, demonstrate reduced gas emission, and their production is cost-effective.

7 cl, 3 tbl, 11 ex

Description

The present invention relates to compositions containing polymers based on carbodiimides, epoxides and polyesters, their preparation and use for the inhibition of hydrolysis.

A wide variety of carbodiimides have proven to be useful in many applications, eg as hydrolysis inhibitors for thermoplastics, ester polyols, polyurethanes, triglycerides, lubricating oils, etc. However, they have disadvantages: the emission of gases, possibly harmful to health, and the very high cost and complexity of production.

Epoxides are cheaper to produce, but they have the disadvantage that they do not achieve stabilization activity against the hydrolysis of carbodiimides even at very high concentrations. They only act as acid scavengers and provide only insufficient long-term stabilization at higher temperatures. Particularly in very demanding applications, such as high atmospheric humidity and temperature conditions, they have insufficient activity as hydrolysis inhibitors, since ester plastics are usually processed at temperatures above 200°C. DE 10349168 A1 describes a hydrolysis inhibitor composed of epoxidized fatty acid esters and glycerides and mixtures thereof with monomeric carbodiimide. The stabilizers described there act as acid scavengers in oils. However, when processed under the above conditions, thermoplastics based on esters show insufficient activity, if any, in terms of long-term resistance to hydrolysis. In addition, as a result of the use of monomeric carbodiimides, the emission of toxic gases increases.

Thus, it is an object of the present invention to provide new, cost effective compositions that are resistant to hydrolysis, exhibit reduced gas emissions, and are cost effective to manufacture.

It has now surprisingly been found that the above object can be achieved using a combination of at least one polymeric aromatic carbodiimide, at least one epoxide having at least 2 epoxy groups, and at least one polymer based on a polyester, in particular polyalkylene terephthalate or polylactide.

Thus, the present invention relates to a composition containing

(a) at least one polymeric aromatic carbodiimide of formula (I)

R ¹ -R ² -(-N=C=NR ² -) _m -R ¹ (I), where

m is an integer from 2 to 500, preferably from 3 to 20, particularly preferably from 4 to 10,

R ² is C ₁ -C ₁₂ -alkyl-substituted arylenes, C ₇ -C ₁₈ -alkylaryl-substituted arylenes and optionally C ₁ -C ₁₂ -alkyl-substituted C ₁ -C ₈ -alkylene-bridged arylenes, containing in total from 7 to 30 carbon atoms, and arylene, preferably

where R ⁶ , R ⁷ and R ⁸ each independently represents methyl or ethyl, where each benzene ring carries only one methyl group and n=1 to 10, and

R ¹ is -NCO, -NCNR ³ -NHCONHR ³ , -NHCONR ³ R ⁴ or -NHCOOR ⁵ where R ³ and R ⁴ are the same or different and are C ₁ -C ₁₂ -alkyl, C ₆ -C ₁₂ -cycloalkyl , C ₇ -C ₁₈ -aralkyl or aryl radical, and R ⁵ represents C ₁ -C ₂₂ -alkyl, C ₆ -C ₁₂ -cycloalkyl, C ₆ -C ₁₈ -aryl or C ₇ -C ₁₈ -aralkyl radical and an unsaturated alkyl radical having 2-22 carbon atoms, or an alkoxypolyoxyalkylene radical _,

(b) at least one epoxide, preferably having at least 2 epoxy groups, and

(c) at least one polyester thermoplastic polymer.

The term "arylene" includes in particular phenylene, naphthalene, anthrylene and/or phenanthrylene radicals, preferably phenylene radicals.

The polymeric aromatic carbodiimides a) are preferably compounds of formula (II)

(II)

(II)

where R ¹ is selected from the group -NCO, -NHCONHR ³ , -NHCONR ³ R ⁴ or -NHCOOR ⁵ where R ³ and R ⁴ are the same or different and represent C ₁ -C ₁₂ -alkyl, C ₆ -C ₁₂ -cycloalkyl , C ₇ -C ₁₈ -aralkyl radical or aryl radical,

R⁵ represents C₁-C₂₂-alkyl, C₆-C₁₂-cycloalkyl, C₆-C₁₈-aryl or C₇-C₁₈an aralkyl radical and an unsaturated alkyl radical having 2-22 carbon atoms, preferably 12-20, particularly preferably 16-18 carbon atoms, or an alkoxypolyoxyalkylene radical, And

R ⁶ , R ⁷ and R ⁸ are each independently methyl or ethyl, where each benzene ring bears only one methyl group and n=1 to 10.

The content of carbodiimide (NCN content determined by titration with oxalic acid) for carbodiimides of formula (II) used according to the invention is preferably 2-14% by mass, preferably 4-13% by mass, particularly preferably 6-12% by mass.

In addition, the carbodiimides used according to the invention preferably have an average molar mass (Mw) of 1000-5000 g/mol, preferably 1500-4000 g/mol, particularly preferably 2000-3000 g/mol, determined by GPC viscometry.

In addition, preference is given to carbodiimides of the formula (II) having a polydispersity D=Mw/Mn of 1.2-2.2, particularly preferably 1.4-1.8.

The carbodiimides are preferably commercially available compounds such as, for example, the Stabaxol® trademark polymeric carbodiimides from Lanxess Deutschland GmbH. However, they can also be obtained, for example, by the methods described in EP14191710.4.

Preferably, component b) contains a total of at least two epoxy groups per molecule, where preferably at least one epoxy group is terminal.

The preparation of epoxidized compounds is also known to those skilled in the art. Preferred epoxidized compounds are polyglycidyl or poly(beta-methylglycidyl) esters, preferably prepared by reacting a compound having at least two free alcohol or phenolic hydroxyl groups and/or reacting the phenolic hydroxyl groups with substituted epichlorohydrin.

Preferred are polyglycidyl or poly(beta-methylglycidyl) ethers, derivatives of acyclic alcohols, in particular ethylene glycol, diethylene glycol and higher poly(oxyethylene)glycols, propane-1,2-diol or poly(oxypropylene)glycols, propane-1,3- diol, butane-1,4-diol, poly(oxytetramethylene) glycols, pentane-1,5-diol, hexane-1,6-diol, hexane-2,4,6-triol, glycerin, 1,1,1- trimethylpropane, bistrimethylolpropane, pentaerythritol, sorbitol or polyepichlorohydrins.

Alternatively, polyglycidyl or poly(beta-methylglycidyl) esters are preferred, derivatives of cycloaliphatic alcohols, in particular 1,3- or 1,4-dihydroxycyclohexane, bis(4-hydroxycyclohexyl)methane, 2,2-bis(4-hydroxycyclohexyl) propane or 1,1-bis(hydroxymethyl)cyclohex-3-ene, or they contain aromatic nuclei based on N,N-bis(8,2-hydroxyethyl)aniline or p,p'-bis(2-hydroxyethylamino)diphenylmethane.

Preferred epoxidized compounds are also based on mononuclear phenols, on polynuclear phenols.

Preferred mononuclear phenols are resorcinol or hydroquinone.

Preferred polynuclear phenols are bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane or 4,4'-dihydroxydiphenylsulfone.

The preferred condensation products of phenols with formaldehyde are phenolic novolacs.

Preferred aromatic epoxy compounds have 2 terminal epoxy functions.

A preferred aromatic epoxy compound having 2 terminal epoxy functions is the oligomeric reaction product of bisphenol A with epichlorohydrin having an average molecular weight (according to EN ISO 10927) of 900 to 1200 g/mol and an epoxy index (according to ISO 3001) of 450 to 600 g for the equivalent. Particularly preferred component c) is the oligomeric reaction product of bisphenol A with epichlorohydrin of formula (III).

(III),

(III)

where a is from 0 to 10, preferably a is from 1 to 8, more preferably a is from 1 to 6, particularly preferably from 2 to 3, where a is an average.

Components c) are preferably obtained by the method according to US2002/0128428 A1 and have an average molecular weight according to EN ISO 10927 from 900 to 1200 g/mol (corresponding in formula (III) to a value of a from 2 to 3) and an epoxy index (according to ISO 3001) from 450 to 600 g per equivalent.

The epoxy compound used according to the invention preferably has a Mettler softening point according to DIN 51920 in the range from 0 to 150°C, even more preferably from 50°C to 120°C, particularly preferably from 60°C to 110°C and in particular , from 75°C to 95°C. The Mettler softening temperature is the temperature at which the sample flows out of a cylindrical nozzle having a drain hole with a diameter of 6.35 mm, thus interrupting the optical shutter, which is located 19 mm below. For this purpose, the sample is heated in air under constant conditions.

Preferably, the epoxy compounds used have an average epoxy equivalent weight (EEW, g of resin containing one mole of epoxy-bonded oxygen), determined by titration according to DIN 16945, in the range from 162 to 2000 g/eq., preferably from 250 to 1200 g/eq. , even more preferably from 350 to 1000 g/eq. and particularly preferably from 450 to 800 g/eq.

Particularly preferably, the compound used as component b) is poly(bisphenol A-coepichlorohydrin) [CAS No. 25068-38-6], preferably having an average molecular weight (M _n ) value determined by MALDI-TOF mass spectrometry, matrix-assisted laser desorption / ionization time-of-flight mass spectrometry according to EN ISO 10927, in the range from 600 to 1800 g /mol obtained, for example, as Epilox® from Leuna Harze GmbH, Leuna.

Still preferred epoxy compounds having at least 2 epoxy functions are from the series of epoxides commercially available under the trademark Joncryl® from BASF AG, eg Joncryl® 4368, which contain the following units in any combination.

,

,

и

And

where R ⁹ , R ^{10 =} independently of each other H, C _{1 -} C ₈ -alkyl, R ¹¹ = independently of each other C ₁ -C ₈ -alkyl, x, y=1-20, z=2-20, where the end groups R* represent H, C ₁ -C ₈ -alkyl.

The epoxide preferably corresponds to the formula (IV)

(IV)

(iv)

where R ⁹ , R ^{10 =} independently of each other H, C _{1 -} C ₈ -alkyl, R ¹¹ = independently of each other C ₁ -C ₈ -alkyl, x, y=1-20, z=2-20, where the end groups R* represent H, C ₁ -C ₈ -alkyl.

Thermoplastic polyester polymers c) are preferably poly-C ₁ -C ₈ -alkyl terephthalates, particularly preferably polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), and copolyesters, thermoplastic polyester elastomers (TPE E), ethylene vinyl acetate (EVA), polylactic acid (PLA) and/or PLA derivatives, polybutylene succinates (PBS), polyhydroxyalkanoates (PHA) and various mixtures thereof.

Polylactides (PLA) are particularly preferred.

In a preferred embodiment of the present invention, the composition of the invention contains:

a) from 0.2% to 2% wt., preferably from 0.4% to 1.5% wt., particularly preferably from 0.5% to 1.0% wt.;

b) from 0.05% to 4% wt., preferably from 0.1% to 2% wt., particularly preferably from 0.5% to 1.5% wt.;

c) from 94% to 99.75% wt., preferably from 96.5 to 99.5% wt., particularly preferably from 97.5 to 99.0% wt.

In another preferred embodiment of the present invention, the compositions do not contain additional components other than components a), b) and c), where the sum of the shares of a), b) and c) is equal to 100% of the mass.

In addition, the present invention relates to a method for producing a composition, according to which the components a) and b) are mixed with at least one thermoplastic polyester polymer c). Here preference is given to extruders or kneaders, extruders are particularly preferred. These are commercially available mixing and stirring units.

In one preferred embodiment of the present invention, the mixing of components a), b) and c) is carried out at temperatures from 150°C to 300°C.

In yet another embodiment of the process according to the invention, additional additives are added to the mixture of components a), b) and c), preferably nucleating agents, fiber reinforcing agents, impact modifiers, flow enhancers and/or UV stabilizers.

The present invention also relates to a method for obtaining hydrolysis-resistant finished products by processing a composition containing components a), b) and c), in at least one mixing unit, preferably a compounder (intensive mixing apparatus0, to shaped materials and their further processing is preferably by injection molding or extrusion to obtain finished products.

The processes according to the invention for producing finished articles by extrusion or injection molding are carried out at melting temperatures ranging from 160 to 330°C, preferably from 190 to 300°C, and optionally also at pressures not exceeding 2500 bar, preferably at pressures not exceeding 2000 bar, even more preferably at pressures not exceeding 1500 bar and particularly preferably at pressures not exceeding 750 bar.

In extrusion, it is preferable to distinguish between an extrusion profile and a sequential co-extrusion profile. Sequential co-extrusion involves extruding two different materials alternately. Thus, a preform is formed having a different composition of the material in sections in the direction of extrusion. It is possible to obtain individual product sections with specifically desired properties throughout the respective material section, e.g. for products with soft edges and a hard middle section or uniform soft bottom areas (Thielen, Hartwig, Gust, "Blasformen von Kunststoffhohlkörpern" [Blow-Moulding of Hollow Plastics Bodies], Carl Hanser Verlag, Munich 2006, pp. 127-129).

The injection molding method includes melting (plasticizing) a raw material, preferably in the form of granules, in a heated cylindrical cavity and pouring it as an injection molding material into a temperature controlled cavity. Compositions according to the invention are used as raw materials, which are preferably already processed into a shaped material by mixing, where said shaped material is in turn preferably processed into a granular material. After cooling (curing) of the molded material poured into the temperature-controlled cavity, the injection molded part is taken out of the mold.

In contrast to injection molding, extrusion uses a continuous plastic extrudate of the molding composition of the invention in the extruder, where the extruder is a machine for producing thermoplastic molded/finished products. Devices used include:

single screw extruders and twin screw extruders and related subgroups,

conventional single screw extruders, conveyor single screw extruders,

twin screw extruders with opposite and unilateral screw rotation.

Extrusion plants preferably consist of the following elements: extruder, mould, downstream equipment, extrusion blow moulds. Extrusion plants for the production of profiles preferably consist of the following elements: extruder, profile mold, sizing element, cooling zone, crawler and roller, separating device and chute. Film extrusion plants consist of the following elements: extruder, cooling zone, stretching zone and roller outlet.

The finished articles obtained according to the invention are preferably materials exposed to an aqueous environment, atmospheric humidity or water splashes.

Such hydrolysis-resistant finished products can be found in automobiles, electronic devices, telecommunications, information technology or computer industries, as well as in the household, sports, medical or entertainment fields. In a preferred embodiment, the compositions according to the invention are used to obtain hydrolysis-resistant films, for example, for packaging or solar cells.

The present invention also relates to the use of the composition according to the invention for the production of finished products by extrusion, preferably for packaging or solar cells.

The scope of the invention covers all of the conventional or preferred definitions of radicals, indices, parameters and explanations thereto, as listed here above and here below, including respective ranges and preferences in any combination.

The examples that follow serve to explain the invention, but are not restrictive.

typical options.

Materials used:

1) Stab. A: monomeric carbodiimide having an NCN content of about 10.8% by weight. in terms of 2,6-diisopropylphenyl isocyanate obtained from Lanxess Deutschland GmbH under the name Stabaxol® I.

2) Stab. B: polymeric carbodiimide having an NCN content of about 11.8 wt %, D=about 1.8 and Mw=2300 g/mol of formula (II), where n=about 3-4, R ⁶ , R ⁷ , R ⁸ each independently represents methyl or ethyl, where each benzene ring carries only one methyl group, R ¹ =-NHCOOR ⁵ and R ⁵ =cyclohexyl.

3) Stab. C: epoxide of formula (III), where n is 2-3 with an epoxy equivalent weight (DIN 16945) of 500 to 700 g/eq. and softening temperature (Mettler, DIN 51920) from 75 to 90°C [CAS No. 25068-38-6].

4) Polyethylene terephthalate (PET) from Novapet.

5) Polyacrylic acid (PLA) obtained from NatureWorks.

Inhibition of hydrolysis in polyethylene terephthalate (PET)

To evaluate the effect of hydrolysis inhibition in PET, the stabilizers used according to Example (Stab A, B and C) are dispersed in PET before determination using a laboratory twin screw extruder ZSK 25 from Werner & Pfleiderer at a temperature of about 280° C., as described below. F3 standard tensile strength test pieces are then prepared from the Arburg Allrounder 320S 150-500 injection molded granular materials.

For the hydrolysis test, these F3 standard test pieces are stored in water vapor at 110° C. and their tensile strength is measured in MPa.

Inhibition of hydrolysis in polylactic acid (PLA)

In order to evaluate the effect of hydrolysis inhibition in PLA, the stabilizers used according to Example (Stub B and C) are dispersed in PLA before determination using a laboratory twin screw extruder ZSK 25 from Werner & Pfleiderer at a temperature of about 200°C, as described below. F3 standard tensile strength test pieces are then prepared from the Arburg Allrounder 320S 150-500 injection molded granular materials.

For the hydrolysis test, these F3 standard test pieces are stored in water at 65° C. and their tensile strength is measured in MPa.

The amounts of mixture components used and the test results are listed in Tables 1 and 2:

Table 1 :

Relative tensile strength (%) Etc. 1 (compar.)
PET Etc. 2 (comp.) PET, 1% Stab A Etc. 3 (comp.) PET, 2% Stab C Etc. 4 (comp.) PET, 4% Stab C Etc. 5 (comp.) PET, 1% Stab A, 1.5% Stab C 0 days 100 100 100 100 100 1 day 75 86 61 63 86 2 days 40 80 33 40 81 3 days 0 64 0 0 65 4 days 44 47 5 days thirty 38

com.=comparative example from DE10349168, fig.=according to the invention

Table 2:

Relative tensile strength (%) Etc. 1
(comp.) PET Etc. 6
(comp.) PET, 1% Stab. B Etc. 7
(image) PET, 1% Stub B, 1.5% Stub C 0 days 100 100 100 1 day 75 86 89 2 days 40 83 89 3 days 0 76 87 4 days 60 82 5 days 40 64 6 days 18 54 7 days 0 40

com.=comparative example, pic.=according to the invention

Table 3 :

Relative tensile strength (%) Etc. 8 (comp.) PLA Ex 9
(comp.) PLA, 4% Stab C Etc. 10
(comp.) PLA, 0.5% Stab B Etc. 11 (image) PLA, 0.5% Stub B, 1.5% Stub C 0 days 100 100 100 100 1 day 94 96 98 98 2 days 62 79 96 97 3 days 22 57 71 97 4 days 0 0 44 97 5 days 0 97 6 days 97 7 days 97 8 days 97 9 days 97 10 days 97 11 days 94 12 days 88 13 days 67 14 days 53 15 days 28 16 days 0

com.=comparative example from DE 10349168, pic.=according to the invention

The percentages given in tables 1 and 2 are the % by weight of the respective stabilizers.

The results of hydrolysis inhibition tests show that the epoxides alone show little if any stabilizing effect, but together with the polymeric carbodiimides of the invention (eg Stab. B) unexpectedly show a clear positive synergistic effect on hydrolysis resistance. In contrast, the combination of monomeric carbodiimides with epoxides does not provide such a synergistic effect.

Claims (25)

1. Composition for obtaining molded products, containing (a) 0.2-2% by weight of at least one polymeric aromatic carbodiimide of formula (II)

where R ¹ is NHCOOR ⁵ , R ⁵ is C ₁ -C ₂₂ alkyl, C ₆ -C ₁₂ cycloalkyl, C ₆ -C ₁₈ aryl or C ₇ -C ₁₈ aralkyl, and an unsaturated alkyl radical having 2-22 carbon atoms, preferably 12-20, preferably 16-18 carbon atoms, or an alkoxypolyoxyalkylene radical, and R ⁶ , R ⁷ and R ⁸ are each independently methyl or ethyl, where each benzene ring bears only one methyl group, and n is between 1 and 10, (b) 0.05-4% by weight of at least one epoxide selected from oligomeric product of interaction of bisphenol A with epichlorohydrin of formula (III),

where a is between 0 and 10, where a is the average, or compounds of formula (IV)

where R ⁹ , R ¹⁰ are H, C ₁ -C ₈ -alkyl, R ¹¹ is C ₁ -C ₈ -alkyl, x, y are 1-20 and z is 2-20, and R* is is H, C _1- C ₈ -alkyl, and (c) 94-99.75% by weight of at least one polyester thermoplastic polymer selected from the group consisting of polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), thermoplastic polyester elastomers (TPE E), ethylene vinyl acetate ( EVA), polylactic acid (PLA) and/or PLA derivatives, polybutylene succinates (PBS), polyhydroxyalkanoates (PHA) and mixtures thereof, thermoplastic polyurethanes, polyurethane elastomers, PU adhesives and PU sealing resins. 2. The composition according to claim 1, characterized in that the epoxide is an oligomeric product of the interaction of bisphenol A with epichlorohydrin, having an average molecular weight (according to EN ISO 10927) from 900 to 1200 g / mol and an epoxy index (according to ISO 3001) from 450 to 600 g per equivalent. 3. Composition according to claim 1 or 2, characterized in that said composition contains a), b) and c) in the following proportions: a) 0.4-1.5% by weight, more preferably 0.5-1.0% by weight, b) 0.1-2% by weight, more preferably 0.5-1.5% by weight, c) 96.5-99.5% by weight, more preferably 97.5-99.0% by weight 4. The method of obtaining a composition according to any one of paragraphs. 1-3, characterized in that the components a) and b) are mixed with at least one polyester-based thermoplastic polymer c). 5. A method for preparing a composition according to claim 4, characterized in that components a) and b) are mixed with at least one polyester-based thermoplastic polymer c) at temperatures of 160-330°C. 6. The finished product obtained by mixing the compositions according to any one of paragraphs. with 1-3, at least one mixing unit, and further processing by injection molding or extrusion to obtain molded materials. 7. The use of compositions according to any one of paragraphs. 1-3 to obtain extruded finished products.