DE19921416A1 - Preparation of glycidyl functional polymers comprises thermally initiated grafting of monomers on polymers with units based on butadienes and acrylonitrile - Google Patents

Abstract

Preparation of glycidyl functional polymers comprises the thermally initiated grafting of monomers on polymers Y/Z, where Y represents units based on butadienes or other conjugated dienes and Z represents units based on acrylonitrile or other alkene nitrile compounds.

Description

Technical field

The present invention describes a process for the preparation of new glycidyl Functionalized polymers based on nitrile rubbers.

Background of the Invention

Functionalized elastomers and the find in numerous publications and patents Making the same description. Elastomers containing epoxy functionalities play an important role in this context.

The desired functionalization is carried out either by suitable copolymerization with epoxy-containing monomers or by grafting epoxy containing monomers on existing ethylenic polymers, such as ethylene Propylene copolymers (EPR), ethylene-propylene-diene terpolymers (EPDM) or ethylene-α- Olefin copolymers.

These elastomers are used, for example, as compatibilizers in Polymer alloys or polymer mixtures, mostly in connection with polar ones thermoplastic polymers such as polyesters or polyamides. The improvement of Impact strength, impact strength and tear resistance of these thermoplastics are often targeted targets of developments in this area.

In the patents US 3,886,227 of May 27, 1975, US 4,026,967 of May 31, 1977, EP 0 149 192 of December 20, 1984, 800.33 of November 21, 1985, EP 0 274 744 of December 28, 1987, U.S. 4,965,111, October 23, 1990, and U.S. Patent 5.008.342 from April 16, 1991 include methods for the functionalization of EPDM and EPR described.

None of the inventions describes the application of glycidyl functionalization Nitrile rubbers.

The long-sighted and widespread opinion, a priori, is partly responsible for this fact polar elastomer materials, such as nitrile rubbers, are not retrofitted for the required ones To make fields of application more polar. The one with the suitable glycidyl functionalization associated further advantage, over the introduced glycidyl functions chemical couplings to polymers with suitable functional groups such as B. carboxy, hydroxyl or amine functions.

The present invention, however, is based on nitrile rubbers and their special methodology to be functionalized with glycidyl-containing monomers.  

Disclosure of the invention

The present invention describes a process for the preparation of new glycidyl Functionalized polymers based on acrylonitrile-butadiene polymers in particular Elastomers.

Formulated more clearly, the compositions according to the invention for the production of new glycidyl-functionalized elastomers based on nitrile rubbers, produced by functionalization during mixing in the molten polymer phase, comprise:

• A) 40-99.95 parts by weight of a polymer X / Y / Z. Y represents in this Connection units based on butadienes or other conjugated Diene compounds and Z units based on acrylonitrile or other alkene nitrile compounds. Component X may or may not be present consisting of units based on carboxyl-containing compounds. In addition, the polymer X / Y / Z can be hydrogenated afterwards available.
• B) 0.05-50 parts by weight of a component that contains glycidly functional Groups and radical graftable functional groups such as vinyl or allyl Contains functions.
• C) 0-10 parts by weight of a component that is thermal or otherwise initiates into free radicals and thus a radical one Grafting reaction of the glycidyl-containing monomeric component to the Elastomer can cause.

If new glycidyl-functionalized elastomers based on nitrile rubbers are produced, which are produced by functionalization in solution, component (D) is also used to dissolve the components mentioned in (A), (B), (C):

• A) solvent, suitable to dissolve the components mentioned under (A), (B), (C).

Typical examples of the polymers mentioned in (A) are acrylonitrile-butadiene copolymers (NBR), hydrogenated acrylonitrile-butadiene copolymers (HNBR), carboxylated acrylonitrile-butadiene Terpolymers (XNBR).

Typical examples of the glycidyl-containing monomers contained in (B) are Glycidyl acrylate, glycidyl methacrylate, glycidyl itaconate, vinyl glycidyl ether, allyl glycidyl ether, 2-methylallylgylcidyl ether and styrene-p-glycidyl ether.  

Components suitable for use in the context of the present invention which are thermally or initiated in another way to free radicals and thus a radical initiated grafting reaction of the glycidyl-containing monomer component to the Can cause elastomer, including peroxidic compounds. Especially Diacyl peroxides, such as. B. di (2,4-dichlorobenzoyl) peroxide, Di (3,5,5-trimethylhexanoyl) peroxide, didecanoyl peroxide, dilauroyl peroxide, di (4- methylbenzoyl) peroxide, dibenzoyl peroxide as well as peroxyl carbonates, such as. B. Tue (2- ethylhexyl) peroxycarbonate, dicyclohexyl peroxydicarbonate, di (4-tert-butylcyclohexyl) peroxydicarbonate, dimyristyl peroxydicarbonate, dicetyl peroxydicarbonate.

Furthermore Perester, such as. B. Di (2-neodecanoyl-peroxy-isopropyl) benzene, tert-amylperoxy deodecanoate, tertiary butyl peroxy neodecanoate, tertiary amyl peroxy pivalate, tertiary butyl peroxy pivalate, tert.-butylperoxy-2-ethylhecanoate, tert.-butylperoxy-3,5,5-trimethylhexanoate, tert.- Butyl peroxy benzoate and perketals, such as. B. 1,1-Di (tert-butylperoxy) 3,3,5- trimethylcyclohexane, 1,1-di (tert.butylperoxy) cyclohexane, 2,2-di (tert.butylperoxy) butane, n- Butyl 4,4-di (tert.butylperoxy) valerate, ethyl 3,3-di (tert.butylperoxy (butyrate, 3,3,6,6,9,9- Hexamethyl-1,2,4,5-tetraoxa-cyclononane and perketals, such as. B. 1.1- Di (tert.butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-di (tert.butylperoxy) cyclohexane, 2,2- Di (tert.butylperoxy) butane, n-butyl-4,4-di (tert.butylpreoxy) valerate, ethyl 3,3- di (tert.butylperoxy) butyrate, 3,3,6,6,9,9-hexamethyl-1,2,4,5-tetraoxa-cyclononane.

Likewise dialkyl peroxides, such as. B. dicumyl peroxide, part. Butylcumyl peroxide, di (tert.butylperoxy isopropyl) benzene, 2,5-dimethyl-2,5-di (tert.butylperoxy) hexane, 2,5-dimethyl-2,5- di (tert.butylperoxy) hexin-3, di (tert.butyl) peroxide and ketone peroxides, such as. B. Methyl isobutyl ketone peroxide, methyl ethyl ketone peroxide, acetylacetone peroxide, Cyclohexanone peroxide and hydroperoxides, such as. B. cumene hydroperoxide, tert.- Amyl hydroperoxide, tert-butyl hydroperoxide.

Examples

In the following examples, the phr ("parts per hundred parts resin") is one Weight-related quantity information related and in such a way that the weight proportion per hundred parts of the main component (polymer) is obtained.

Melt kneading is carried out with the aid of kneaders known to those skilled in the art, such as e.g. B. Brabender® type internal mixer, Banbury® mixer, roller and others Kneaders, single or twin screw extruders and various other extruders.

Specifically, an internal mixer of the type Brabender® Plasticorder PL 2000 used with online torque and temperature measurement. The kneading blades are selected with high shear.

In the examples and comparative examples, the following acrylonitrile butadiene Copolymers, hydrogenated acrylonitrile butadiene copolymers, carboxylated acrylonitrile butadiene Terpolymers, glycidy-containing compounds and peroxides used:  

Acrylonitrile-butadiene copolymer:

• 1. Perbunan NT 3946 (NBR-1),
  Component (X): not available; Component (Y): acrylonitrile content: 40.0 ± 1.0;
  Mooney viscosity ML (1 + 4) 100 ° C: 37 ± 5,
  Bayer AG, Leverkusen, Germany.
• 2. Perbunan NT 2831 (NBR-2),
  Component (X): not available; Component (Y): acrylonitrile content, 28.6 ± 1.0;
  Mooney viscosity ML (1 + 4) 100 ° C: 30 ± 5,
  Bayer AG, Leverkusen, Germany.

Hydrogenated acrylonitrile-butadiene copolymer (HNBR):

• 1. Therban XN 540 A,
  Component (X): not available; Component (Y): acrylonitrile content: 34.0 ± 1.0;
  Mooney viscosity ML (1 + 4) 100 ° C: 63 ± 7,
  Residual double bond content: max 0.9%,
  Bayer AG, Leverkusen, Germany.

Carboxylated acrylonitrile-butadiene copolymer (XNBR):

• 1. Nipol 1072,
  Component (Y): acrylonitrile content: 27,
  Mooney viscosity ML (1 + 4) 100 ° C: 47 ± 7,
  Component (X): acrylic acid; Carboxyl group content: 0.075 ephr,
  Zeon GmbH, Düsseldorf, Germany.

Glycidyl-containing compounds:

• 1. glycidyl methacrylate (GMA),
  C ₆ H ₁₀ O ₂ ; FW: 142.15; bp: 189 ° C,
  Sigma-Aldrich-Chemie GmbH.
• 2. Allyl glycidyl ether (AGE)
  C ₆ H ₁₀ O ₂ ; FW: 114.14; bp: 154 ° C / 760,
  Sigma-Aldrich-Chemie GmbH.

Peroxides:

• 1. dicumyl peroxide (DCP),
  Perkadox BC,
  Akzo Nobel Chemicals GmhH, Germany.
• 2. 2,5-dimethyl-2,5-di (tert.butylperoxy) hexane (Tri-101),
  Trigonox 101,
  Akzo Nobel Chemicals GmhH, Germany.
• 3. 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane (Tri-29),
  Trigonox 29 B90,
  Akzo Nobel Chemicals GmhH, Germany.

Solvent:

• 1. ortho-dichlorobenzene (o-DCB),
  Sigma-Aldrich-Chemie GmbH.

Each composition had a number of physical properties measured. Unless otherwise stated, the samples were examined as follows:

The degree of GMA grafting was determined by FTIR spectroscopy. The sample material was pressed under 120 ° C, 80 kN pressure, 4 minutes into films of about 10 microns thick. These films were measured in transmission in a Nicolet P 510 FTIR spectrometer and evaluated with computer support. The degree of GMA grafting in the rubber was determined by creating and measuring defined mixtures of (H, X) NBR-g-GMA and GMA-containing polyethylenes. The evaluation was carried out on the basis of characteristic signal bands in the substances. The CH ₂ rocking vibration at 721 cm ^-1 for ethylene units and the CN stretching vibration at approx. 2200 cm ^{-1 were} selected as characteristic bands. The C = O stretching vibration at ∼1720 cml was defined as characteristic of the GMA. The quotient was formed from the integral absorptions of the characteristic signals. This could be quantitatively assigned by means of previously created calibration measurements of materials of a defined, known composition and thus the degree of GMA grafting in the material could be determined. All determinations were verified by means of quantitative elemental analysis on a Perkin Elmer Elementary Analyzer EA 240.

To differentiate between grafted and homopolymerized GMA, the Samples are subjected to a cleaning method prior to being pressed into FTIR films Homopolymerized as well as monomeric GMA can separate from the sample. The degree of crosslinking of the samples was determined analogously to the ASTM standard D-3616 performed in boiling p-xylene. After applying the method insoluble mass fraction of the material compared with the mass of the starting material and the gel content of the sample is determined.

Examples 1-10

The (H, X) NBR polymer was at 110 ° C and 20 revolutions per minute (rpm) in Internal mixer melted by kneading. A pre-made mix of peroxide and Glycidyl-containing monomer was added in portions and briefly in the Melt homogeneously dispersed. The grafting reaction of the glycidyl-containing monomer was due to an increase in speed and the associated additional Heat generation initiated by shear loading the sample by adding the peroxide breaks down into free radicals above a certain temperature. The course of the Grafting reaction was tracked by measuring the online torque. The Reactions were made after reaching a stable torque level and a few more Moments knead broken off. The material was removed from the kneading chamber and Allow to cool to room temperature. The gel content was as described above  determined. To determine the degree of GMA grafting, the samples correspond to the cleaned and analyzed method described above.

Example 11

Elastomer was in the internal mixer at 140 ° C and 20 revolutions per minute (rpm) melted kneading. The glycidyl-containing monomer is melted metered in portions and briefly homogenized. The grafting reaction of the glycidyl containing monomer by increasing the kneading chamber temperature, caused by electrical resistance heating elements in the chamber walls and by a speed increase and the associated additional heat development through Initiated shear stress on the sample. To determine the degree of GMA grafting, the Samples are cleaned and analyzed according to the method described above.

Example 12

The reactions were carried out in a three-necked flask with KPG stirrer with constant degassing the solution with nitrogen. Neatly shredded pieces of the elastomer were dissolved in o-dichlorobenzene at 140 ° C with stirring. After all admitted When the polymer had dissolved, the GMA was added. For this solution, the im initiator dissolved in the same solvent. Thereupon the temperature became below constant stirring of the solution by external heating to about 160 ° C and the Grafting reaction initiated. After the completion of the reaction, the solution became under added constant stirring to cold acetone and the polymer precipitated. The polymer was further extracted in a Soxhlett apparatus with acetone for about 8 hours and then dried in a vacuum drying cabinet at 60 ° C. overnight.

The compositions of the mixtures, the determined GMA grafting levels and Gel contents are shown in Table 1 and Table 2.

It is worth mentioning in the sense of the invention that the grafting should preferably be carried out in the melt. Temperatures which are at a maximum and at which peroxidic initiation can still be preferred are preferred. This reduces evaporation losses of the glycidyl-containing monomer.

Claims (9)

1. A process for the preparation of glycidyl-functionalized polymers, characterized in that the glycid-containing monomers in a thermally initiated reaction to a polymer of the structure Y / Z, where Y in this context represents units based on butadienes or other conjugated diene compounds and Z units based on acrylonitrile or other alkene-nitrile compounds known to those skilled in the art as NBR rubbers. 2. Process for the preparation of glycidyl-functionalized polymers according to claim 1, characterized in that the polymers Y / Z were subsequently hydrogenated, the Are known to those skilled in the art as HNBR rubbers. 3. Process for the preparation of glycidyl-functionalized polymers according to claim 1, characterized in that the polymers X / Y / Z are composed of units Y and Z according to claim 1 and additionally from units based on Acrylic acids and / or other alkene carboxylic acids, which experts call XNBR Rubbers are known. 4. Process for the preparation of glycidyl-functionalized polymers according to the Claims 1 to 3, characterized in that the glycidyl functionalization takes place during a mixing process in the molten phase. 5. Process for the preparation of glycidyl-functionalized polymers according to the Claims 1 to 3, characterized in that the functionalization is not in the Melt, but is made in suitable solvents. 6. Process for the preparation of glycidyl-functionalized polymers according to the Claims 1 to 3, characterized in that the glycidyl functionalization is started specifically by thermally initiated decomposition of peroxides. 7. Process for the preparation of glycidyl-functionalized polymers according to the Claims 1 to 3, characterized in that the glycidyl functionalization is started specifically by thermally initiated decomposition of peroxides, the Decay temperature is in the range of 90 ° -130 ° C to evaporation losses of the Minimize glycidyl-containing monomers. 8. Process for the preparation of glycidyl-functionalized polymers according to the Claims 1 to 3, characterized in that the glycidyl functionalization especially by thermally initiated decomposition of 1,1-bis (tert-butylperoxy) -3,3,5-trimethyl- cyclohexane is started.   9. Process for the preparation of glycidyl-functionalized polymers according to the Claims 1 to 3, characterized in that the glycidyl functionalization is pure initiated thermally, i.e. without the use of peroxides.