DE10311987A1 - Functionalized styrene/olefin block copolymers, used as self-adhesive coating material, in thermoplastic (film) laminate or as compatibilizer in polymer or composite, are graft modified with unsaturated acid, anhydride or epoxide - Google Patents

Abstract

0.02-10 wt.% functionalized styrene/olefin block copolymers (I) comprise (wt.%) 70-99.7% particulate styrene/olefin block copolymer [graft substrate (II)], graft modified at 100-200[deg]C by 0.3-20% alpha ,beta -ethylenically unsaturated mono- or dicarboxylic acid, anhydride and/or epoxide and optionally comonomer, using substrate with given melt flow index and average particle diameter of 0.01-8 mm. Functionalized styrene/olefin block copolymers (I) with a degree of functionalization of 0.02-10 wt.% comprise (wt.%) 70-99.7% particulate styrene/olefin block copolymer [graft substrate (II)], graft modified at reaction temperatures of 100-200[deg]C, whilst maintaining its solid-liquid state, by means of 0.3-20% functional monomer (III) selected from alpha ,beta -ethylenically unsaturated mono- or dicarboxylic acids or their anhydrides and alpha ,beta -ethylenically unsaturated epoxides, including mixtures of these with a comonomer (IV), and 0-10% organic peroxide free radical initiator (V) with a half life of 2-150 minutes at 230-70[deg]C. (II) has a melt flow index (MFI) from 200 g/10 minutes (230[deg]C/2.16 kg) to less than 0.2 g/10 minutes (300[deg]C/2.15 kg) (to ISO 1133) and average particle diameter of 0.01-8 mm. An independent claim is also included for production of functionalized block copolymers (I).

Description

The invention relates to functionalized Styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10% by mass as well a process for their manufacture.

Hydrogenated linear styrene / butadiene (and / or isoprene) block copolymers and also hydrogenated radial styrene / diene block copolymers with a residual portion on unsaturated Bonds <20 %, preferably ≤ 5 %, are for numerous areas of application, which increase the adhesive strength of the styrene / olefin block copolymers obtained in this way need and an improved tolerance to possess polar thermoplastic plastics, not usable without further ado.

For their use as adhesives or adhesion promoters in laminates and Laminated as well as a compatibility agent in different polymer blends and / or composites Styrene / olefin block copolymers therefore in an additional Process step, mostly by grafting carboxyl-containing Monomers, such as (meth) acrylic acid, fumaric acid and other α, β-unsaturated mono- or dicarboxylic acids or their anhydrides, preferably maleic anhydride, or also of monomer compounds containing epoxy groups, such as especially glycidyl (meth) acrylate, functionalized.

The coupling of such functional monomers done to one by radical transfer or high-energy radiation at the by means of selective hydrogenation the butadiene and / or Isoprene segments obtained elastomeric ethene-butene or ethene (ethene) propene blocks of the Block copolymers generated radical site. Thereby - under consideration of the specific reaction components - various graft polymerization technologies applied.

For example, the functional monomer, especially maleic anhydride, is the preferred grafting agent in an extruder on a block copolymer backbone, preferably styrene / ethene-butene / styrene (SEBS) or styrene / ethene-propene / styrene (SEPS) and styrene / ethene Grafted ethene-propene / styrene three-block copolymers (SEEPS) and corresponding four-block copolymers of the structure SEPSEP or SEBSEB, mostly using an organic peroxy compound as a radical generator with a half-life relevant for a reaction temperature between 150 and 250 ° C ( EP 0173380 A1 . EP 0085115 B1 . EP 0216347 B1 . EP 0262691 B1 . EP 0371001 B1 . EP 0322977 B1 ; US 5,066,726 ).

The reaction temperature to be selected for the melt grafting depends on the melt viscosity of the styrene / olefin block copolymers used. Linear three-block copolymers SEBS and SEPS or SEEPS with weight-average molar masses M _w > 50,000 g / mol are generally only with the acceptance of a higher degree of molar mass degradation and especially with M _w > 150,000 g / mol generally only by adding a flow accelerator using mostly very high reaction temperatures can be functionalized up to above 300 ° C ( EP 0261748 A2 ). At these high temperatures, strong decomposition phenomena occur in the presence of peroxides. On the other hand, the monomers evade the grafting reaction because of their high volatility, which is a major reason for the low grafting efficiency.

The demand for functionalized block copolymers with M _w > 70,000 g / mol results from the need to improve the mechanical and thermal strength of the thermoplastic elastomer (TPE) compounds made therefrom, in particular to achieve lower compression set residues and improved fogging behavior. However, the block copolymers require such high melting temperatures that they cause their degradation when grafted in the melt. Furthermore, due to the toxic vapors of monomers and volatile (low molecular weight and oligomeric) by-products released at the high reaction temperatures, considerable signs of corrosion can be observed in the reaction extruder.

In addition to melt grafting (reactive extrusion), the solution grafting of the block copolymers at lower temperatures is known ( US 4,692,357 . US 4,883,834 . EP 0173380 A1 ). However, this grafting technology is very costly because of the use of larger amounts of solvent, especially because of the separation and recovery of the solvent that is necessary after the grafting from the reaction product, as well as product cleaning.

If the functionalization, in particular the maleination, is carried out without the addition of initiator, the monomer molecules couple to the double bonds remaining in the olefinic blocks after the selective hydrogenation of the diene blocks by means of the so-called ENE (addition) reaction ( US 4,427,828 . EP 0173380 A1 ).

As an alternative to modification the styrene / olefin block copolymers in their melt or solution state the functionalization carried out at temperatures up to a maximum of 100 ° C is firmer particulate Block copolymer backbones known.

This technology, known as solid-phase functionalization, includes the grafting of monomer molecules which have carboxyl or anhydride, epoxy or other functional groups onto which they are present in a powdery, granular, crumbly, flaky, granular or other dry-flowable state To understand backbone polymer ( EP 0642538 B1 . DE 4342605 A1 ).

The advantage of modifying the backbone polymers (also known as graft substrates) in their tro The free-flowing state at temperatures significantly below their melting or softening points compared to the melting modification carried out at much higher temperatures lies in the avoidance or strong suppression of the occurrence of toxic vapors of monomers and volatile reaction by-products as well as in the gentler treatment and thus the degradation minimization of those used graft substrates.

The disadvantage of the known solid-phase functionalization carried out at reaction temperatures between 40 and 100 ° C., preferably between 50 and 90 ° C., is - despite the use of high initiator concentrations - the low reaction rates and the formation of heterogeneous graft products ( EP 0642538 B1 . DE 4342605 A1 ).

High molecular weight and therefore mechanically and thermally more resilient styrene / olefin block copolymers with a high oil addition> 20% by mass, generally 60 - 150 parts by weight of paraffinic and / or naphthenic process oil per 100 parts by weight of block copolymer, in the same reaction temperature range between 50 and 90 ° C graft-modifiable with reasonable sales ( DE 19502206 A1 . EP 0805827 B1 ). The high oil content has proven to be a weak point for the production of sophisticated TPE compounds, especially for use in the automotive sector and for other high-quality technical and household products.

The property profile of the means Modified styrene / olefin block copolymers obtained by known solid phase grafting is not sufficient the high demands regarding heat resistance and mechanical resilience, which generally refers to the process management in the Temperature range below 100 ° C and the one for it applied formulation, including either too low Block copolymer molar masses or excessive process oil proportions.

The object of the present invention consisted in the development of functionalized styrene / olefin block copolymers with degrees of functionalization between 0.02 and 10 mass%, the the described disadvantages of known functionalized styrene / olefin block copolymers, especially their limited thermal and mechanical resilience, do not have and thus an expanded Use as adhesive, coupling agent, adhesion and tolerance agent allow, as well as in the development of a process for their manufacture.

• – 70 bis 99,7 Masse-% eines partikulären Styrol/Olefin-Blockcopolymers mit einer Schmelzflussrate MFR (300°C/2,16 kg) ≥ 0,2 g/10 min (nach DIN ISO 1133) entsprechend gewichtsmittleren Molmassen M_w zwischen 20.000 und 200.000 g/mol sowie einem mittleren Teilchendurchmesser (d_T) zwischen 0,01 und 8 mm unter Aufrechterhaltung ihres festfluiden Zustandes mittels
• – 0,3 bis 20 Masse-% eines Funktionsmonomers aus der Reihe der α,β-ethylenisch ungesättigten Mono- oder Dicarbonsäuren bzw. ihrer Anhydride sowie der α,β-ethylenisch ungesättigten Epoxide, einschließend Mischungen des Funktionsmonomers mit einem Comonomer, und gegebenenfalls unter Verwendung von
• – bis 10 Masse-% eines organischen peroxidischen Radikalbildners, der eine Halbwertszeit zwischen 2 und 150 min im Temperaturbereich zwischen 230 und 70°C besitzt,

bei Reaktionstemperaturen zwischen 100 und 200°C pfropfmodifiziert worden ist.The present invention relates to functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10% by mass, obtained in that

• - 70 to 99.7 mass% of a particulate styrene / olefin block copolymer with a melt flow rate MFR (300 ° C / 2.16 kg) ≥ 0.2 g / 10 min (according to DIN ISO 1133) corresponding to weight-average molar masses M _w between 20,000 and 200,000 g / mol and an average particle diameter (d _T ) between 0.01 and 8 mm while maintaining their solid fluid state by means of
• - 0.3 to 20% by mass of a functional monomer from the series of the α, β-ethylenically unsaturated mono- or dicarboxylic acids or their anhydrides as well as the α, β-ethylenically unsaturated epoxides, including mixtures of the functional monomer with a comonomer, and optionally below use of
• Up to 10% by mass of an organic peroxidic radical generator which has a half-life between 2 and 150 min in the temperature range between 230 and 70 ° C,

has been graft modified at reaction temperatures between 100 and 200 ° C.

As backbone polymers to be modified (Graft substrates) linear or radial styrene / olefin multi-block copolymers, preferably linear styrene / olefin tri and - Four-block copolymers with a total styrene content between 5 and 85% by mass, based on the total block copolymer mass, in a dry-flowable consistency, preferably powdery, flaky, crumbly, granular, granular or other particulate form be used.

The styrene / olefin block copolymers are made using known methods by selective hydrogenation of linear and radial block copolymers consisting of monovinyl aromatic hydrocarbon segments, preferably from styrene and / or substituted (alkylated and / or halogenated) styrenic blocks (S), and conjugated Diene segments, preferably made from butadiene (1,3) and / or methylbutadiene (1,3) (isoprene) assembled blocks (B and / or I), the different blocks (S, B and / or I) being sharp be separated from one another or have “smeared” transitions (tapered sections) can, with olefinic residual unsaturation degrees <20 o, preferably ≤ 5%.

Particularly suitable backbone polymers are those by selective hydrogenation of linear styrene / butadiene / styrene three-block copolymers (symmetrical SBS or asymmetrical SBS ', where S and S' represent styrene blocks with different sequence molecular weights) with one in the end blocks (S, S ') Total styrene content in the block copolymer between 5 and 85% by mass, preferably between 10 and 70% by mass, and a vinyl group content in the butadiene center block between 10 and 80%, preferably between 25 and 65%, of styrene / ethene-butene / styrene triblock copolymers produced (SEBS, SEBS ') and the corresponding styrene / isoprene / styrene (SIS or SIS') or styrene / butadiene-isoprene / styrene three-block co polymeric (SBIS or SBIS ') styrene / ethene-propene / styrene (SEPS, SEPS') or styrene / ethene-ethene-propene / styrene three-block copolymers (SEEPS, SEEPS ').

The corresponding four-block copolymers with one additional each olefinic outer block EB or EP or EEP (SEBSEB, SEPSEP or SEEPSEEP), the styrene and / or olefin blocks are the same or can also have different sequence molecular weights as backbone polymers according to the invention usable.

The styrene / olefin multi-block copolymers used according to the invention cover a melt viscosity range corresponding to melt flow rates MFR (230 ° C / 2.16 kg) of 200 g / 10 min to MFR (300 ° C / 2.16 kg) of 0.2 g / 10 min (according to DIN ISO 1133), which generally have molecular weights M _w between 20,000 and 200,000 g / mol.

The group of block copolymer backbones that can be used also includes compositions consisting of 80-100% by mass, preferably 90-99.9% by mass of styrene / olefin block copolymer, and 20-0.0% by mass, preferably 10-0, 05% by mass, an organic solvent and / or a process oil consisting entirely or predominantly of paraffinic and / or naphthenic fractions, included. In addition to the use of conventional aromatic or (cyclo) aliphatic solvents, especially small process oil additives are preferred, which - in contrast to high oil concentrations according to the known solid phase grafting ( EP 0805827 B1 ) - do not change the structure of the block copolymer backbone and thus its melting behavior. Small amounts of solvent or oil serve for better initiator and, if appropriate, monomer dispersion on the graft substrate and, moreover, as an auxiliary for the intended subsequent graft product processing, in particular as a compatibilizer in the production of special compounds.

Α, β-ethylenically unsaturated mono- and dicarboxylic acids, such as especially (meth) acrylic or fumaric acid, acid anhydrides, such as particularly Maleic and itaconic anhydride, and α, β-ethylenic unsaturated epoxidic compounds, such as especially glycidyl acrylate and methacrylate, used. Preferred functional monomers are acrylic acid (AS), maleic anhydride (MSA) and glycidyl methacrylate (GMA).

MSA is the most preferred Functionalizing.

The functional monomers (FM) can also as a mixture with a comonomer (CM) from the non-polar range or opposite the FM used has a significantly lower hydrophilicity α, β-ethylenically unsaturated low molecular weight compounds according to compositions 100 - 20% by mass FM and 0 - 80 % By mass CM, preferably 90-30 Mass% FM and 10 - 70 % By mass CM.

Particularly suitable comonomers are monovinylaromatic compounds, preferably styrene and / or α-methylstyrene, and / or C ₁ - to C ₁₂ -alkyl esters of acrylic or methacrylic acid, such as especially ethyl acrylate (EA) and / or n-butyl acrylate (BA) and / or methyl methacrylate (MMA) is used. Styrene is the preferred comonomer.

For a number of use cases have "(co) graft" portions by means of Use of FM / CM mixtures, especially MSA / styrene or also AS / styrene and GMA / styrene compositions, for the Control of special graft product properties as advantageous proved.

The radical graft reaction is used, in particular to achieve higher levels of functionalization as well as an even grafting, advantageous in the presence of an organic peroxy group-containing Radical generator with a half-temperature after one hour (measured as a 0.2 molar solution in benzene) between 70 and 200 ° C carried out.

Selected examples of this are dilauroyl peroxide with a 1-hour half-life temperature (T _{HW / 1h} ) of 80 ° C, dibenzoyl peroxide (DBPO) with T _{HW / 1h} of 92 ° C, tert.-butyl peroxy-2-ethylhexanoate with T _{HW / 1h} 92 ° C, tert-butyl peroxy-isobutyrate with T _{HW / 1h} 95 ° C, tert-Butylmonoperoxy maleate with T _{HW / 1h} 104 ° C, tert-butyl perbenzoate (TBPB) with T _{HW / 1h} 125 ° C, dicumyl peroxide (DCP) with T _{HW / 1h} 135 ° C, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane (DHBP) with T _{HW / 1h} 138 ° C , 2,5-Dimethyl-2,5-di (tert-butylperoxy) hexin (3) (DYBP) with T _{HW / 1h} at 149 ° C, di-tert.-butylperoxide (TBP) with T _{HW / 1h} of 149 ° C, cumene hydroperoxide with T _{HW / 1h} of 190 ° C and tert-butyl hydroperoxide with T _{HW / 1h} of 200 ° C, in a concentration based on the block copolymer backbone between 0.002 and 10 mass%, preferably between 0.005 and 2 mass% can be used.

For Reaction temperatures above 100 ° C are especially DBPO, TBPB, DCP, DHBP, DYBP and TBP in one related to the block copolymer backbone Concentration between 0.01 and 1 mass% preferred. Such low Initiator concentrations are for the usual ones Solid phase grafting processes are not known.

It is useful to use polymerization mixtures from 0.3 to 20 mass% FM, preferably 0.5 to 10 mass% FM, including FM / CM mixtures with a maximum of 80% by mass of CM, and radical formers accordingly mass ratios from the monomer (s) to be used (FM + CM) and radical generator between 200 and 0.2, preferably between 50 and 1 to use.

• A) in der Dispergierstufe – 70 bis 99,7 Masse-% eines partikulären Styrol/Olefin-Blockcopolymers mit einer Schmelzflussrate MFR (300°C/2,16 kg) ≥ 0,2 g/10 min (nach DIN ISO 1133) sowie einem mittleren Teilchendurchmesser (d_T) zwischen 0,01 und 8 mm allein oder gegebenenfalls zusammen mit – bis 10 Masse-% eines organischen peroxidischen Radikalbildners, der eine Halbwertszeit zwischen 2 und 150 min im Temperaturbereich zwischen 230 und 70°C besitzt, bei einer Dispergiertemperatur (T_D) im Bereich zwischen 10 und 50°C vorgelegt wird und anschließend – 0,3 bis 20 Masse-% eines Funktionsmonomers (FM) aus der Reihe der α,β-ethylenisch ungesättigten Mono- oder Dicarbonsäuren und/oder ihrer Anhydride oder der α,β-ethylenisch ungesättigten Epoxide, gegebenenfalls in Form ihrer Mischungen mit bis maximal 80 % Comonomer (CM), bezogen auf die Gesamtmonomer (FM + CM)-Masse, aus der Reihe der monovinylaromatischen Verbindungen und/oder der C₁- bis C₁₂-Alkylester der (Meth)Acrylsäure, hinzugesetzt werden und die Reaktionsmischung unter gleichzeitiger Dispersion mittels Stickstoffspülung inertisiert wird und danach
• B) in der Aufheizstufe die Mischung von der Dispergiertemperatur T_D auf die Endreaktionstemperatur T_R zwischen 100 und 200°C unter Aufrechterhaltung der fest-fluiden Konsistenz der Reaktionsmischung aufgeheizt wird und anschließend
• C) in der Reaktionsstufe unter Aufrechterhaltung der Endreaktionstemperatur T_R (± 10°C) zwischen 100 und 200°C die Pfropfreaktion in der fest-fluiden Reaktionsmischung bis zum Endumsatz geführt wird und danach
• D) in der Desorptionsstufe unter Temperaturabsenkung mittels Durchleiten von Stickstoff und gegebenenfalls unter Absenkung des Druckes im Reaktionsgefäß bei einer Desorptionstemperatur T_Des zwischen der Reaktionstemperatur T_R und 80°C der nicht umgesetzte Monomeranteil aus der Reaktionsmischung entfernt sowie gegebenenfalls vorhandener Restinitiator deaktiviert wird

und anschließend
nach Temperaturabsenkung auf eine Endtemperatur unterhalb 80°C das trockene funktionalisierte Styrol/Olefin-Blockcopolymer dem Reaktionsgefäß entnommen wird.Another object of the present invention is a process for the production of functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10% by mass, characterized in that

• A) in the dispersion stage - 70 to 99.7 mass% of a particulate styrene / olefin block copolymer with a melt flow rate MFR (300 ° C / 2.16 kg) ≥ 0.2 g / 10 min (according to DIN ISO 1133) and an average particle diameter (d _T ) between 0.01 and 8 mm alone or optionally together with - up to 10% by mass of an organic peroxidic radical generator, which has a half-life between 2 and 150 min in the temperature range between 230 and 70 ° C, at a Dispersed temperature (T _D ) in the range between 10 and 50 ° C and then - 0.3 to 20% by mass of a functional monomer (FM) from the series of α, β-ethylenically unsaturated mono- or dicarboxylic acids and / or their anhydrides or the α, β-ethylenically unsaturated epoxides, optionally in the form of their mixtures with up to 80% comonomer (CM), based on the total monomer (FM + CM) mass, from the series of the monovinylaromatic compounds and / or the C ₁ - to C ₁₂ alkyl esters of (meth ) Acrylic acid, are added and the reaction mixture is rendered inert by means of nitrogen purging while simultaneously dispersing and then
• B) in the heating stage, the mixture is heated from the dispersion temperature T _D to the final reaction temperature T _R between 100 and 200 ° C. while maintaining the solid-fluid consistency of the reaction mixture and then
• C) in the reaction stage while maintaining the final reaction temperature T _R (± 10 ° C) between 100 and 200 ° C, the grafting reaction is carried out in the solid-fluid reaction mixture until the final conversion and then
• D) in the desorption stage by lowering the temperature by passing nitrogen through and, if appropriate, by lowering the pressure in the reaction vessel at a desorption temperature T _Des between the reaction temperature T _R and 80 ° C., the unreacted monomer fraction is removed from the reaction mixture and any residual initiator present is deactivated

and subsequently
after lowering the temperature to a final temperature below 80 ° C., the dry functionalized styrene / olefin block copolymer is removed from the reaction vessel.

• – für die Dispergierstufe A) eine Dispergierzeit t_D zwischen 5 und 60 min,
• – für die Aufheizstufe B) eine Aufheizzeit t_A zwischen 5 und 120 min,
• – für die Reaktionsstufe C) eine Reaktionszeit t_R zwischen 5 und 90 min sowie
• – für die Desorptionsstufe D) eine Desorptionszeit t_Des von 5 bis 12 0 min.

The times that can be assigned to the individual process stages A) to D) can be selected within wide ranges. The following have proven to be particularly advantageous time periods for the method according to the invention:

• For the dispersion stage A) a dispersion time t _D between 5 and 60 min,
• - for heating stage B) a heating time t _A between 5 and 120 min,
• - For reaction stage C) a reaction time t _R between 5 and 90 min and
• - For the desorption stage D) a desorption time t _Des of 5 to 12 0 min.

The heating stage B), in which - depending on the radical offer, in particular on initiator type and concentration - the grafting reaction begins and is carried out up to a certain conversion, can be designed differently. Technologically preferred is either continuous heating in a single stage (without a stopover) in the time t _A directly to T _R or in two stages (with a stopover), after which heating is carried out in a first time interval t _A * <t _A until one is reached provisional reaction temperature T _A * <T _R , at which the reaction takes place over a period of time t _R *, and is then heated from T _R * to the final reaction temperature T _R in a period t _A - (t _A * + t _R *).

The functionalization, in particular Maleinierung, the block copolymers according to the invention can be done without the addition of a radical generator, the "ENE" addition of MSA one of the remaining double bonds in the olefinic middle block Contribution to the "connection" of succinic anhydride groups guaranteed.

The specific use of the peroxidic radical generator, ie the choice in terms of its chemical structure, half-life and its concentration, depends on the degree of functionalization to be achieved. Furthermore, the exact comparison with the current reaction conditions, in particular T _R and t _R , type and concentration of FM and CM and the form of the addition of the reaction components (batch or semi-batch procedure) takes place.

The preparation of the reaction mixture, its dispersion and inertization in accordance with stage A) and heating to T _{A in} accordance with stage B) and the functionalization reaction which generally begins in stage B) and continues in reaction stage C), ie the reaction of FM or FM / CM-Ge Mix at reaction end temperatures (T _R ) between 100 and 200 ° C, preferably between 105 and 180 ° C, are expediently carried out in the reaction vessel in which the reaction mixture is kept in the solid-fluid state.

After functionalization T _Des is preferably between T _R and 100 ° C and desorption times t _Des preferably between 10 and 50 min, the unreacted fraction of monomer (s) from the reaction mixture by passing nitrogen is expelled and optionally still remaining initiator disabled in desorption. At the same time, an antioxidant in the usual concentrations can be added during or at the end of the desorption stage.

This temperature control underlying the present invention within the entire process is particularly advantageous for the gentle treatment of the reaction product due to the avoidance of temperature increases above T _A for the desorption stage following the grafting reaction.

After residual monomer desorption has taken place, the reaction product is usually cooled further to a temperature below T _Des - up to a maximum of room temperature - and removed from the reactor.

Surprisingly, by means of the process according to the invention, styrene / olefin multiblock copolymers within a wide molar mass range, in particular linear SEBS and linear SEPS or SEEPS with M _w between about 40,000 and 200,000 g / mol or melt viscosities corresponding to MFR (230 ° C. / 2.16 kg) from 100 g / 10 min to MFR (300 ° C / 2.16 kg) from 0.2 g / 10 min, which is only in the lower molar mass range (M _w ≤ 100,000 g / mol) by means of reactive extrusion can be functionalized with a satisfactory result.

The solid-phase graft modification of multi-block copolymers with M _w > 100,000 g / mol, in particular with M _w ≥ 150,000 g / mol, has previously been possible only if their viscosity by means of a higher oil content (≥ 20% by mass, generally> 50% by mass) %) had previously been reduced, as a result of which the resulting functionalized block copolymers, due to the high oil content, remained unsuccessful, particularly in the automotive sector.

The styrene / olefin block copolymers modified according to the invention have high functionality through the high adhesion and peel strengths when used in coatings, laminates and composite films result. Furthermore, those with the graft products according to the invention are distinguished modified polymer, especially TPE compounds, through an improved mechanical characteristic level, especially due to high impact and notched impact strengths, Flexural strength and modulus of elasticity when ensuring high elongation at break values, as well as an improved thermal resilience, recognizable by lower Fogging values and a very limited odor nuisance, out.

This high level of properties is based on the general modifiability of styrene / olefin block copolymers with different melt viscosities corresponding to the above-mentioned MFR range, their degradation, which cannot be observed or can only be observed to a small extent as a result of the functionalization reaction, and thus the general securing of high molar masses of M _w ≥ 40,000 g / mol and on the other hand to a very uniform distribution of functional groups attached (grafted) to the backbone chain, so when using MSA or specific MSA / styrene mixtures especially succinic anhydride (BSA) groups or defined “BSA- styrene Copfropf "spacers.

There is also the advantage of the process according to the invention across from functionalization of the melt, especially in its high cost-effectiveness. That is due to the easy-to-control solid phase process with simultaneous achievement high monomer sales (very low residual monomer content) and in avoiding a damage or decomposing the block copolymer structure as above the Block copolymer melting or softening point z. T. be observed. In this context it is particularly surprising that by means of very low initiator concentrations, which in general one to two powers of ten below the concentrations for the known ones Solid phase and also below that for most melt grafting technologies lie, modified by high reaction rates styrene / olefin block copolymers can be obtained with high degrees of functionalization.

The functionalized styrene / olefin block copolymers with Functionalization levels between 0.02 and 10 mass%, preferably between 0.1 and 5 mass%, as a self-adhesive coating material on different surfaces, as a component or separate layer in different thermoplastic Multi-layer films, laminates and as a compatibilizer in polymer blends and / or -composites very well suited.

The styrene / olefin block copolymers functionalized according to the invention, especially those based on linear SEBS and SE (E) PS, and the method used to manufacture them are described by the following Examples explained without being limited to that to be.

In order to characterize the block copolymer graft substrates used and the functionalized graft products obtained, instead of the MFR values, the volume flow indices (MVR) measured directly with a melt index device from Göttfert (model MP-D) are compared to those used for the Temperature (230 - 320 ° C) applicable melt densities (between 0.5 and 0.8 g / cm ³ ) multiplied MFR-Wer ten correspond.

example 1

In a temperature-controlled, vertical 200 l reactor equipped with a stirring device (length / diameter ratio: 1.5 to 1), 100 parts by mass of SEEPS are grafted, characterized by an MVR (320 / 1.2 kg) value of 4 , 2 g / 10 min, d _T of 0.32 mm and a styrene content of 30% by mass (SEEPS-1), together with 0.1 part by weight of 2,5-dimethyl-2,5-di (tert. -butylperoxy) hexane (DHBP) and 0.1 part by weight of white oil at an internal reactor temperature of 20 ° C and dispersed in a nitrogen atmosphere at 80 min ^{-1 for} a total of 30 min while increasing the temperature to 33 ° C, at the same time completely removing the residual moisture by means of vacuum becomes. Then 2.1 parts by weight of MSA are added at 33 ° C., the stirrer speed is increased to 440 min ⁻¹ and the reaction mixture is rendered inert to a dispersion temperature T _D of 55 ° C. within 20 min by means of multiple nitrogen flushing with simultaneous temperature increase. Under a nitrogen atmosphere and further stirring, the temperature of 60 ° C is heated at a heating rate of 2.9 ° C / min to a final reaction temperature T _R of 155 ° C, after which T _R and the stirring of 360 to 320 min ^-1 the reaction is carried out over a period t _R of 60 min. Then 0.2 mass% of tris (nonylphenyl) phosphite (TNPP) is added as an antioxidant and the reaction is ended by reducing the stirring speed to 80 min ⁻¹ by passing nitrogen through the fluid reaction product mass and unreacted MSA and volatile Reaction by-products are driven out.

After a desorption time t _Des of 45 min, the reaction product cooled down to a temperature of 145 ° C. is passed into a cooling mixer, from where, after further cooling, it reaches the storage container from which samples are taken for subsequent determination of the characteristic value.

• – Auswaage des Reaktionsproduktes
• – Gehalt an Carbonsäure, berechnet auf Masse-% MSA, mittels Rücktitration der durch den Carbonsäureanteil nicht neutralisierten Kalilauge, indem eine 2 g-Probe der Auswaage sechs Stunden mit einer Mischung aus 100 ml Xylol und 20 ml 0,1-molarer methanolischer Kalilauge bei 80°C behandelt und nach Zugabe eines Tropfens Phenolphthalein mittels 0,1-molarer Salzsäure titriert wird: – für die (getrocknete) Auswaage den Carbonsäuregehalt CS (berechnet als MSA-Masseanteil) und – für den im siedenden Methanol erhaltenen Rückstand, d. h. den vom Blockcopolymer-Rückgrat chemisch gebundenen („gepfropften") MSA-Masseanteil CS_ex, der sogenannte Funktionalisierungs- bzw. Maleinierungsgrad.

Be determined:

• - Weighing of the reaction product
• - Carboxylic acid content, calculated on mass% MSA, by back-titration of the potassium hydroxide solution not neutralized by the carboxylic acid content by adding a 2 g sample to the balance for six hours with a mixture of 100 ml xylene and 20 ml 0.1-molar methanolic potassium hydroxide solution 80 ° C and after adding a drop of phenolphthalein is titrated with 0.1 molar hydrochloric acid: - for the (dried) weight, the carboxylic acid content CS (calculated as the MSA mass fraction) and - for the residue obtained in boiling methanol, ie from Block copolymer backbone chemically bound ("grafted") MSA mass fraction CS _ex , the so-called degree of functionalization or maleination.

• – der mittels Methanol bei Raumtemperatur gelöste Anteil der (getrockneten) Auswaage, ein niedermolekulareres MSA-Peroxid-Reaktionsprodukt PMSA, und
• – der mittels siedendem Methanol aus dem Extrakt ermittelte Anteil an oligomeren MSA-Peroxid-Reaktionsprodukt P(MSA)_ex.
• – MVR-Wert nach DIN ISO 1133 (320°C/21,6 kg Auflagegewicht)

The following have also been determined:

• - The portion of the (dried) scale dissolved by means of methanol at room temperature, a low molecular weight MSA-peroxide reaction product PMSA, and
• - The proportion of oligomeric MSA-peroxide reaction product P (MSA) _ex . Determined from the extract by means of boiling methanol.
• - MVR value according to DIN ISO 1133 (320 ° C / 21.6 kg bearing weight)

Characteristic values for the maleated SEBS (example no. 1): Final weight 101.9 parts by weight (sales of 80.2%) Carboxylic acid content CS 1.64 mass% Degree of functionalization CS _ex 1.42 mass% PMSA share 0.02 mass% P (MSA) _ex share 0.08 mass% MVR (320 / 21.6) 166 cm ^3/10 min

Examples 2 to 24

According to the process control described in Example 1, using one of the following powdery block copolymer backbones
SEBS-1: styrene content = 22% by mass; MVR (320 ° C / 2.16 kg) = 128 cm ^3/10 min
SEBS-2: styrene content = 56% by mass; MVR (320 ° C / 2.16 kg) = 4.3 cm ^3/10 min
SEBS-3: styrene content = 30% by mass; MVR (320 ° C / 1.2 kg) = 24 cm ^3/10 min; M _w = 55,000
SEBS-4: styrene content = 30% by mass; MVR (320 ° C / 1.2 kg) = 4.4 cm ^3/10 min; M _w = 72,000
SEBS-5: styrene content = 31% by mass; MVR (320 ° C / 21.6 kg) = 13 cm ^3/10 min; M _w = 120,000
SEBS-6: styrene content = 32% by mass; MVR (320 ° C / 21.6 kg) = 7.9 cm ^3/10 min; M _w = 175,000
SEEPS-1: styrene content = 30% by mass; MVR (320 ° C / 1.2 kg) = 4.2 cm ^3/10 min; M _w = 75,000
SEEPS-2: styrene content = 30% by mass; MVR (320 ° C / 21.6 kg) = 3 cm ^3/10 min; M _w = 176,000
with one of the initiators mentioned below, a functional monomer - apart from MSA also AS or GMA - and optionally a comonomer - besides styrene (S) also MMA and BA - in different concentrations or functional monomer (FM) / comonomer (CM) mass ratios according to the invention functionalized SEBS and SEEPS block copolymers.

While the same dispersion / inerting stage as in Example 1 was chosen (t _D = (20 + 5) min; T _D between 50 and 60 ° C), the heating and reaction conditions, including the form of addition of the reaction components ( single presentation of all reaction components or monomer replenishment) have been varied. Examples are also given with a two-stage reaction procedure (Ex. Nos. 11, 22 and 24), characterized by the fact that after the dispersion / inertization, first in a time t _A * to a first reaction temperature T _R * of 95-97 ° C. in which the reaction over a time t _R * of 18-30 minutes, and after heating for about ten minutes to a final reaction temperature T _R of 115-120 ° C. in which the reaction is carried out over a total time of 20-30 minutes.

The listed graft parameters CS, CS _ex and HP _ex (especially P (MSA) _ex when using MSA, P (AS) _ex from AS and P (GMA) _ex from GMA as FM) are in% by mass (Ma. -%), based on 100 parts by weight of graft product, the acid determination described in Example 1 for the MA titration also being used when using AS as FM (in% by weight AS). The grafted GMA fractions were determined from the mass balance and oxygen analysis.

In some examples, the backbone polymers, together with the initiator, contain amounts of 0.05 to 2% by mass, based on the backbone polymer mass, of a high-boiling, predominantly aliphatic process oil (density = 0.865 g / cm ³ , dynamic viscosity = 0.28 Pa · s; paraffinic / naphthenic hydrocarbon fraction = 68/32 mass%) added.

The following peroxidic are used Initiators: dilauroyl peroxide (DLPO), dibenzoyl peroxide (DBPO), dicumyl peroxide (DCUP); 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane (DHBP) and 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne (3) (DYBP).

• – Beispiel-Nummer und Rückgratpolymer (Spalte 1)
• – Art und Konzentration des Radikalbildners in Ma.-% (Spalten 2 und 3)
• – Konzentration der FM (MSA, AS, GMA) in Ma-% (Spalte 4) und
• – Konzentration der CM (S, MMA und BA) sowie des Prozessöls in Ma.-% (Spalte 5)
• – Aufheizzeiten (t_A, t_A*): durchgehend bis zur Endreaktionstemperatur T_A (t_A) oder bis zur Zwischen-Reaktionstemperatur T_R* (t_A*) in min (Spalte 6)
• – Reaktionstemperaturen (T_R*, T_R) in °C (Spalte 7)
• – Reaktionszeiten (t_R*, t_R) in min (Spalte 8)
• – Desorptionszeit (t_Des) in min (Spalte 9)

Table 1 lists the process parameters:

• - Sample number and backbone polymer (column 1)
• - Type and concentration of the radical generator in mass% (columns 2 and 3)
• - Concentration of FM (MSA, AS, GMA) in mass% (column 4) and
• - Concentration of the CM (S, MMA and BA) and the process oil in% by mass (column 5)
• - Heating times (t _A , t _A *): continuously up to the final reaction temperature T _A (t _A ) or up to the intermediate reaction temperature T _R * (t _A *) in min (column 6)
• - reaction temperatures (T _R *, T _R ) in ° C (column 7)
• - Response times (t _R *, t _R ) in min (column 8)
• - Desorption time (t _Des ) in min (column 9)

For comparison, Table 1 contains the production of SEEPS-1 and SEEPS-2 functionalized at T _R below 100 ° C (Vg1.1A: without oil and Vg1.5A: with 50% by mass oil) as well as three modified SEBS (Vg1. 7A and Vg1.12A: with 60 and 50 o oil and Vg1.15A: without oil).

Table 1

As in Example 1, the functionalized styrene / ethene-butene / styrene and styrene / ethene-ethene-propene / styrene block copolymers prepared according to further Examples 2 to 24 are generally each by adding 0.2% by weight of TNPP after a desorption time t _Des of 30 min at the end of the reaction, ie immediately before desorption - was stabilized.

Table 2

• – MVR (320 °C/2,16 kg) oder (320°C/21,6 kg) in cm³/10 min (Spalte 2)
• – umgesetzter Funktionsmonomeranteil CS (Spalte 3) und chemisch gebundener („gepfropfter") MSA- oder AS- oder GMA-Anteil im Extraktionsrückstand CS_ex, in Ma.-% (Spalte 4)
• – aus niedermolekularen Monomer-Initiator-Verbindungen bestehender extrahierter „Oligomer"-Anteil (PMSA_ex bzw. PAS_ex, PGMA_ex), in Ma.-% (Spalte 5) sowie
• – Güte: visuelle Beurteilung gespritzter Probekörper bezüglich Oberflächengüte und Verfärbung (Gelbstich) sowie Verarbeitbarkeit von Zusammensetzungen aus 37 Masseteilen funktionalisiertes SEBS oder SEEPS, 45 Masseteilen oben verwendetes Öl und 18 Masseteilen Polypropylen zu 2 mm-Spritzplatten mit entsprechender qualitativer Benotung (Spalte 6): 1 – sehr gut, 2 – gut, 3 – befriedigend, 4 – schlecht, 5 – nicht verarbeitbar.

Table 2 lists the characteristic values that are important for evaluating the reaction products as modifiers in polymer blends and / or polymer composites and for direct use as coating material or adhesion promoter layer:

• - MVR (320 ° C / 2.16 kg), or (320 ° C / 21.6 kg) in cm ^3/10 min (column 2)
• - Converted functional monomer fraction CS (column 3) and chemically bound ("grafted") MSA or AS or GMA fraction in the extraction residue CS _ex , in% by mass (column 4)
• - Extracted “oligomer” fraction (PMSA _ex or PAS _ex , PGMA _ex ) consisting of low molecular weight monomer initiator compounds, in mass% (column 5) and
• - Quality: Visual assessment of sprayed test specimens with regard to surface quality and discoloration (yellow tinge) as well as the processability of compositions consisting of 37 parts by weight of functionalized SEBS or SEEPS, 45 parts by weight of oil used above and 18 parts by weight of polypropylene to form 2 mm spray plates with the corresponding qualitative grade (column 6): 1 - very good, 2 - good, 3 - satisfactory, 4 - bad, 5 - cannot be processed.

Through the choice of the specific process parameters (temperature / time regime, initiator / functional monomer concentrations, comonomer and / or oil content, monomer / initiator mass ratio), specific product parameters, in particular different degrees of functionalization with specific to negligible permissible "oligomer" portion HP _ex (PMSA _ex , PAS _ex , PGMA _ex ) and the MVR or MFR values required for the intended use or processing, adjustable.

Claims (12)

Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass%, characterized in that - 70 to 99.7 mass% of a particulate styrene / olefin block copolymer with a melt flow rate MFR (300 ° C / 2, 16 kg) ≥ 0.2 g / 10 min (according to DIN ISO 1133) corresponding to a weight-average molar mass M _w between 20,000 and 200,000 g / mol and an average particle diameter between 0.01 and 8 mm (graft substrates) while maintaining their solid-fluid state by means of - 0.3 to 20% by mass of a functional monomer from the series of the α, β-ethylenically unsaturated mono- or dicarboxylic acids or their anhydrides and the α, β-ethylenically unsaturated epoxides, including mixtures of the functional monomer with a comonomer, and if appropriate using - up to 10 mass% of an organic peroxidic radical generator, which has a half-life between 2 and 150 min in the temperature range between 230 and 70 ° C, at Reaction temperatures between 100 and 200 ° C has been graft modified. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass% Claim 1, characterized in that as the backbone polymers to be modified linear or radial styrene / olefin multi-block copolymers with olefinic Degrees of residual unsaturation <20%, preferably <5%, and one in the end blocks Total styrene content in the block copolymer between 5 and 85 % in particulate dry flowable form have been used. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass% the claims 1 and 2, characterized in that as the backbone polymers to be modified by selective hydrogenation of linear styrene / butadiene / styrene triblock copolymers (SBS or asymmetrical SBS ', where S and S 'styrene blocks with represent different sequence molecular weights) with one in the end blocks (S, S ') in the block copolymer contained total styrene content between 5 and 85% by mass, preferably between 10 and 70% by mass, as well as one contained in the block of butadiene Vinyl group content between 10 and 80 o, preferably between 25 and 65%, styrene / ethene-butene / styrene triblock copolymers (SEBS, SEBS ') and the corresponding from styrene / isoprene / styrene (SIS or asymmetrical SIS ') or styrene / butadiene-isoprene / styrene three-block copolymers (SBIS or asymmetrical SBIS ') manufactured styrene / ethene propene / styrene (SEPS, SEPS ') or Styrene / ethene-ethene-propene / styrene three-block copolymers (SEEPS, SEEPS ') and the corresponding four-block copolymers, each with an additional one olefinic outer block EB or EP or EEP (SEBSEB, SEPSEP or SEEPSEEP), the styrene and / or Olefinblöcke may have the same or different sequence molecular weights, in powdery, flaky, crumbly, grained granular or other dry-flowable form have been used are. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass% one or more of the claims 1 to 3, characterized in that the backbone polymer in one composition 80 to 100% by mass of styrene / olefin block copolymer and 20 to 0 % By mass of organic solvent and / or completely or predominantly consisting of paraffinic and / or naphthenic parts mineral oil has been used. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass% one or more of the claims 1 to 4, characterized in that α, β-ethylenically unsaturated mono- and dicarboxylic acids, such as especially (meth) acrylic or fumaric acid, acid anhydrides, such as particularly Maleic and itaconic anhydride, and α, β-ethylenic unsaturated epoxidic compounds, such as especially glycidyl acrylate and glycidyl methacrylate, have been used. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10% by mass according to one or more of claims 1 to 5, characterized in that the functional monomer (FM) as a mixture with a comonomer (CM) from the series of α , β-ethylenically unsaturated vinyl aromatics and / or C ₁ - to C ₁₂ -alkyl esters of acrylic or methacrylic acid in a composition of 100 to 20% by mass of FM and 0 to 80 have been used. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass% according to claim 6, characterized in that functional monomer (FM) / comonomer (CM) mixtures in a ratio of 100 to 20 mass% FM and 0 to 80 mass% CM, preferably 90 to 30 Mass% FM and 10 to 70 mass% CM have been used. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass% one or more of the claims 1 to 7, characterized in that the peroxy group-containing used Radical generator under dilauroyl peroxide, dibenzoyl peroxide, tert-butyl-peroxy-2-ethylhexanoate, tert-butyl-peroxy-isobutyrate, tert-butyl-monoperoxy-maleate, tert-butyl perbenzoate, dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butyl peroxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne (3), Di-tert-butyl peroxide, cumene hydroperoxide and tert-butyl hydroperoxide in a concentration related to the block copolymer backbone between 0.002 and 10% by mass, preferably between 0.005 and 2 % By mass are. Functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass% one or more of the claims 1 to 8, characterized in that the radical generator containing peroxy groups with dibenzoyl peroxide, tert-butyl perbenzoate, dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butyl peroxy) hexane, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne (3) and di-tert-butyl peroxide in a block copolymer backbone Concentration between 0.01 and 1 mass% has been selected. Process for the preparation of functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10 mass%, characterized in that A) in the dispersion stage - 70 to 99.7 mass% of a particulate, highly viscous styrene / olefin block copolymers with a melt flow rate MFR (300 ° C / 2.16 kg) ≥ 0.2 g / 10 min and an average particle diameter between 0.01 and 8 mm alone or optionally together with - up to 10% by mass of an organic peroxidic radical generator, which has a half-life between 2 and 150 min in the temperature range between 230 and 70 ° C, is presented at a dispersion temperature (T _D ) in the range between 10 and 50 ° C and then - 0.3 to 20% by mass of a functional monomer (FM ) from the series of the α, β-ethylenically unsaturated mono- or dicarboxylic acids and / or their anhydrides or the α, β-ethylenically unsaturated epoxides, optionally in the form of their mixtures with up to a maximum of 80% como nomer (CM), based on the total monomer (FM + CM) composition of the series of monovinyl aromatic compounds and / or C ₁ - to C ₁ 2 alkyl ester of (meth) acrylic acid, are added and the reaction mixture with simultaneous dispersion is inertized by means of nitrogen purging and then B) in the heating stage, the mixture is heated from the dispersion temperature T _D to the final reaction temperature T _A between 100 and 200 ° C. while maintaining the solid-fluid consistency of the reaction mixture and then C) in the reaction stage while maintaining the Final reaction temperature T _R (± 10 ° C) between 100 and 200 ° C the grafting reaction is carried out in the solid-fluid reaction mixture until the final conversion and then D) in the desorption stage by lowering the temperature by passing nitrogen and, if appropriate, by lowering the pressure in the reaction vessel a desorption temperature T _Des between the final reaction temperature T _R and 80 ° C the unreacted monomer portion is removed from the reaction mixture and any residual initiator present is deactivated and the dry functionalized styrene / olefin block copolymer is then removed from the reaction vessel after lowering the temperature to a final temperature below 80 ° C. A process for the preparation of functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10% by mass according to claim 10, characterized in that - for the dispersion stage A) a dispersion time t _D between 5 and 60 minutes, - for the heating stage B) a heating time t _A between 5 and 120 min - for the reaction stage C) a reaction time t _R between 5 and 90 min and - for the desorption stage D) a desorption time between 5 and 120 min is selected. Use of functionalized styrene / olefin block copolymers with a degree of functionalization between 0.02 and 10% by mass according to one or more of claims 1 to 11 as a self-adhesive coating material on different surfaces, as a component or separate layer in various thermoplastic multilayer films and laminates and as a compatibility agent in polymer blends and / or composites.