DE1945025A1 - Liquid polymers for use in coating or encapsulation - applications - Google Patents

Abstract

Block copolymers are prepared by (1) polymerising a diolefin (I) at 0 - 100 C using 0.005 to 0.2 mole (per mole of diolefin) of a catalyst RLi where R is a C2-20 (cyclo)alkyl or aryl group, (2) contacting the polymer with up to 10 moles % (based on polymer units) of a polyvinyl aromatic hydrocarbon (II) at between -30 degrees C and 50 degrees C, and (3) deactivating the catalyst and recovering the copolymer. A terpolymer is produced if a monovinyl aromatic (III) is included in the step (1) polymerisation or if the polydiolefin is contacted with the polymer of a monovinyl aromatic monomer prior to step (2). The copolymers are liquids of low viscosity (0.05 to 200 stokes). Use as coating or encapsulating polymers is possible. The polymers are reactive and can be cured with peroxides in short reaction times. Generally (I) is a C4-10, despecially C40-6, diene and in particular is butadiene, isoprene, piperylene or dimethylbutadiene; (II) is a divinyl or trivinyl aromatic and is especially divinylbenzene; (III) is especially styrene. Preferably 2.5 to 5 moles % of (II) are used based on (I). Typical curing conditions of the copolymers are 15 min to 48 hours at 90 to 180 degrees C.

Description

Polymer of an aromatic multivinyl hydrocarbon.

The present invention relates to a polymer of an aromatic Multivinyl hydrocarbon that copolymerizes with a diolefin homopolymer or with a copolymer of a diolefin and a monovinyl aromatic hydrocarbon ter -polymerized.

High molecular weight rubber-like copolymers made from conauged Dienes and aromatic monovinyl compounds are known (see U.S. Patent No.

3.198.774 and UK Patent No. 964.4'78) but these are Copolymers in the form of elastomeric solids for encapsulation purposes totally unsuitable.

The production of solid, high-molecular terpolymers is also important by converting a monomer mixture of diolefin, monovinyl and multivinyl - flavored with a peroxide catalyst. Such terpolymers are ' cannot be used for encapsulation purposes because they are insoluble and highly cross-linked.

According to U.S. Patent 3,185,659, graft polymers can be used for Concealment purposes hereby -.

will be that you first an aromatic monovinyl compound in the presence of a peroxide catalyst with a polydiolefin (manufactured under Use of a sodium catalyst) and then a 'divinyl aromatic added together with further amounts of a peroxide catalyst; such terpolymers but can also be prepared by reaction of the sodium catalyst Polydiolefins with a mixture of a monovinylaromatic and Milti -vinylaromatic be prepared in the presence of a peroxide catalyst, or after a third Alternative method by treating one made with a sodium catalyst Mixed polymers of diolefin and monovinylaromatic with a multivinylaromatic and a peroxide catalyst.

It is known that castable diolefin homopolymers and copolymers can be used can be formed by conventional alkyl lithium polymerization processes. the However, the reactivity of these polymers is not sufficient to keep them within a reasonable period of time at elevated temperature using organic To be able to cure peroxides. However, own Polydiolefins, such as e.g. polybutadiene, with a sufficiently high molecular weight and a predominantly 1,2-vinyl structure they do have the necessary responsiveness, but unfavorably they have one very high viscosity so that they can be used with inert or reactive diluents need to be moved.

It is known that an encapsulation system should ideally be solvent-free be.

According to the invention, a highly reactive block polymer is now obtained provided with suitable viscosity for solvent-free encapsulation processes. This block polymer is either (a) aromatic multivinyl hydrocarbon, which has been copolymerized with a homopolydiolefin, or as (b) more aromatic Multivinyl hydrocarbon formed with a mixed polymer of a diolefin and a monovinyl aromatic hydrocarbon was terpolymerized prior to In der As a rule, the diolefin consists of a conjugated diene, which is 4 to 10, preferably Has 4 to 6 carbon atoms. Examples of suitable diolefins include: 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 1,3-pentadiene (piperylene), 2,3-dimethyl-1,3 butadiene etc., as well as their mixtures.

The aromatic multivinyl hydrocarbon is one with 10 to 40 carbon atoms, according to the formula in which # z is an aromatic nucleus such as benzene, naphthalene, biphenyl, phenanthrene, etc. and the symbols R1, R2, R3 and R4 are each, independently of one another, hydrogen atoms, C1-C12-alkyl or cycloalkyl groups or vinyl groups. Specific examples of suitable multivinyl aromatic hydrocarbons are divinylbenzene, divinyltoluene, divinylxylene, isopropenylstyrene, diisopropenylbenzene, trivinylbenzene, divinylnaphthalene, etc., with divinylbenzene being preferred. Based on the number of monomeric units in the homopolydiolefin or in the mixed polymer of diolefin and aromatic monovinyl hydrocarbon, ie the “base” homopolymer or “base” mixed polymer, the amount of aromatic multivinyl hydrocarbon used is generally about 0.5 to 10 , preferably 2.5 to 5 mol%. Amounts of the same of more than 10 mol% should not be used, since they give small and non-liquid polymers.

The aromatic monovinyl hydrocarbon for the production of the mixed polymer from diolefin and aromatic monovinyl hydrocarbon (which in turn is used for the production of the terpolymer which can be cast at room temperature) contains 8 to 40 carbon atoms and corresponds to the general formula in which denotes an aromatic nucleus and R R'2, R'3, R'4 5 and are each, independently of one another, hydrogen atoms or C1-C15-alkyl or cycloalkyl groups. The aromatic monovinyl hydrocarbon is generally used in such amounts that, based on the total number of monomeric units in the copolymer of diolefin and aromatic monovinyl hydrocarbon, up to about 50, preferably up to 30, mol% of monomeric units of the aromatic monovinyl - Hydrocarbons are incorporated.

Examples of suitable aromatic monovinyl hydrocarbons are Styrene, 3-methylstyrene, 3-ethylstyrene, 3,5-diethylstyrene, 4-n-propylstyrene, 2,4,6- Trimethylstyrene, 4-dodecylstyrene, 3-methyl-5-nhexylstyrene, 4-cyclohexylstyrene, 4-phenylstyrene, 2-ethyl-4-benzylstyrene, 4-p-tolylstyrene, 3,5-diphenylstyrene, 2,4,6-'2ri-tert-butylstyrene, 2,3,4,5-tetra -methylstyrene, 4- (4-phenyl-n-butyl) -styrene, 3- (4-n-hexyl-phenyl) -styrene, l-vinylnaphthalene, 2-vinyl-naphthalene, 4,5-dimethyl-1-vinylnaphthalene, 3-ethyl-1-vinylnaphthalene, 6-isopropyl-1-vinylnaphthalene, 2,4-diisopropyl-1-vinylnaphthalene, 3,6-di-p-tolyl-1-vinylnaphthalene, 6-cyclohexyl-1-vinylnaphthalene, 4,5-diethyl-8-octyl-1-vinylnaphthalene, 3,4,5,6-tetramethyl-1-vinylnaphthalene, 3,6-di-n-hexyl-1-vinylnaphthalene, 8-phenyl-1-vinylnaphthalene, 5- (2,4,6-trimethylphenyl) -1-vinylnaphthalene, 4-n-propyl-5-n-butyl-2-vinylnaphthalene, 3-methyl-5,6-diethyl-8-n-propyl-2-vinylnaphthalene, 4-o-tolyl-2-vinylnaphthalene and 5- (3-phenyl-n-propyl) -2-vinylnaphthalene.

According to the invention, the aromatic multivinyl hydrocarbon with a pre-formed "base" homopolymer or copolymer, i.e. the homopolydiolefin or the mixed polymer of diolefin and aromatic monovinyl hydrocarbon, co-polymerized or ter; polymerized, because usually can be with Suitable polymers that can be cast at room temperature cannot be mixed or mixed directly Terpolymerization of a monomer mixture of diolefin and aromatic monovinyl hydrocarbon and multivinyl aromatic hydrocarbon.

The "base" homopolymer, i.e. the homopolydiolefin contains usually from about 5 to about 200, preferably from 10 to 100, total monomeric diolefin units and the "base" copolymer, i.e. the copolymer of diolefin and aromatic Monovinyl hydrocarbon, also has about 5 to about 200 total, preferably 10 to 100 monomer units, which in turn at least about 50, preferably at least 70 mole percent of monomeric diolefin units and up to about 50, preferably up to 30 mol of monomeric units of the aromatic monovinyl hydrocarbon can exist.

Me polymers from the mixed or terpolymerization of an aromatic Multivinyl hydrogen with a homopolydiolefin or a mixed polymer made of diolefin and aromatic monovinyl hydrocarbon are practically solvent-free, but still pourable (i.e. liquid) at room temperature.

The bulk viscosity of these pourable at room temperature Polymer is about 0.05 to about 200, preferably 0.1 to 100 stokes, measured at room temperature (i.e. at 16-250C).

Forms the first stage in the manufacture of these novel polymers the production of the base polymer, i.e. the homopolydiolefin or the mixed polymer also diolefin and aromatic monovinyl hydrocarbon.

For this purpose, the monomer (or monomers) is used in a suitable amount with an organolithium catalyst in the presence of an inert diluent, in the catalyst is sufficiently soluble, brought into contact. In the first stage, a "live", lithium-containing homopolydiolefin is now formed or a "living", lithium-containing copolymer of diolefin and aromatic Monovinyl hydrocarbon. The term "living" here means that the lithium-containing Eomo or mixed polymers after adding additional quantities of aromatic multivinyl hydrocarbon Block copolymers or interpolymers is able to form without further amounts of organolithium catalyst must be added.

The organolithium catalyst which can be used according to the invention can represented by the formula ELi in which R is a CZ-020 -alkyl, -aralkyl- or represents a cycloalkyl group; Substances like methyllithium or phenyllithium are consequently unsuitable. Examples of suitable organolithium catalysts are n-propyllithium, isopropyllithium, n-butyllithium, tert.-octyllithium, n-decyllithium, Benzyllithium, 4-phenyl-n-butyllithium, cyclohexyllithium, 4-cyclohexyl-n-butyllithium or the like .. The butyllithium compounds, i.e. n-sec.- iso- and tert-butyllithium are particularly preferred.

In contrast to U.S. Patent 3,439,064, the present Invention no cocatalysts such as monoamines, diamines, polyamines, ethers, polyethers, cyclic ethers, thioethers, polythioethers, cyclic thioethers or the like in connection used with the catalyst system. Such cocatalysts lead to formation of polymers with high Share at least 50, more likely at least 75 mole percent 1,2 or 3,4 structures. According to the invention, however, the polymers must predominantly (at least 80 mol%) have a 1,4 structure.

As already mentioned, the base polymer is produced preferably using an inert diluent in which the organolithium Catalyst is soluble. Such an inert diluent can contain 4 to 16 carbon atoms contain, for example, aliphatic hydrocarbons such as n-pentane, n-hexane, isooctane, n-nonane, etc., from alicyclic hydrocarbons such as cyclopentane, Cyclohexane, cycloheptane, etc. or from aromatic hydrocarbons such as benzene, Toluene, xylene, chlorobenzene or the like. The amount of the for the aforementioned Purpose-used diluent is not critical, provided that there is enough of it is used um.die amount of organolithium catalyst used soluble close. In general, 0.5 up to 200, preferably 1 to 50 liters of diluent per mole of organolithium Catalyst used.

The amount of used to make the base polymer Organolithium catalyst and the amount of monomer used are different from each other depending, the amount of monomer in turn on the desired degree of polymerization of the base monomer (or base monomers) is dependent. The degree of polymerization (DP) gives in the sense of the present Invention the total number of monomers Diolefin attachments or to monomeric -n units of diolefin-aromatic monovinyl hydrocarbon that is present in the base homopolymers or base copolymers.

Generally speaking, it was found that the degree of polymerization with the amount of catalyst present (in moles) in inverse proportion and d changes with the amount of monomer (in moles) in a direct ratio The degree of polymerization can be determined by the following equation :; Moles of monomers total

Degree of polymerization = moles of organolithium catalyst Da num die desirable total number of monomeric Eirilleiten in the base homopolymer or, Base copolymers above with about 5 to about 200, preferably with 10 to 100 was specified, it follows that for the preparation of the base homopolymer or base copolymers usually from about 0.005 to about 0.2, preferably 0.01 up to 0.1 moles of organic catalyst per mole of total monomer in the base homopolymer or copolymers are used.

The reaction conditions in the production of the base polymer are not critical, but for reasons of convenience, the polymerization takes place generally at 0 to 100, preferably at 20 to 60 ° C for 20 minutes to 24 hours, preferably 40 minutes to 3 hours, with the pressure can fluctuate between negative and positive atmospheric pressure, but preferably Atmospheric pressure prevails.

After production of the "living", lithium-containing base polymer becomes the selected aromatic multivinyl hydrocarbon in the aforementioned amount added to the reaction mixture. The mixed or perpolymerization of the aromatic Multivinyl hydrocarbons with the basic homopolydiolefin or

the basic mixed polymer of diolefin and aromatic monovinyl hydrocarbon takes about 1 minute to about 2 hours, preferably 2 minutes to 1 hour a temperature between about -30 and about + 5000, preferably between 0 and 40 ° C, whereby the pressure can fluctuate between negative and positive atmospheric pressure, but preferably atmospheric pressure prevails. The viscosity of the resulting Mixed or terpolymers depends to a certain extent on the or lerpolymerization applied reaction conditions, but is obtained within of the condition range just mentioned is generally a castable at room temperature Polymer with a bulk viscosity of about 0.05 to about 200 Stokes, measured at room temperature.

The second reaction stage can be carried out according to various methods will. According to the first method, the aromatic multivinyl hydrocarbon the lithium-containing homopolydiolefin with the formation of a lithium-containing block copolymer added. The second method is a mixture of Monomer Diolefin and aromatic monovinyl hydrocarbon to form a lithium-containing copolymer copolymerized, which is then mixed with the aromatic multivinyl hydrocarbon is added to form a lithium-containing block terpolymer. After The third method is the lithium-containing homopolydiolefin with the production of a lithium-containing one Mixed polymer of polydiolefin and aromatic monovinyl hydrocarbon mixed with the aromatic monovinyl compound, after which the aromatic multivinyl compound is added, so that a lithium-containing block terpolymer is formed.

According to the fourth "series" method, a lithium-containing Rlock-1s1ischpolymerisat formed.

For this purpose, either (a) a lithium-containing homopolydiolefin is used and then the aromatic monovinyl hydrocarbon is added, or (b) a mixture of the monomeric diolefin and ilonovinyl aromatic hydrocarbon copolymerized.

The lithium-containing block copolymer is mixed with the monomeric Diolefin, then (optionally) with aromatic monovinyl hydrocarbon etc. added, the reaction by the addition of aromatic multivinyl hydrocarbon is finally terminated to form a lithium-containing block terpolymer.

The lithium-containing block copolymer cannot be mixed by copolymerization a mixture of monomeric diolefin and aromatic multivinyl hydrocarbon be prepared, because such a procedure leads to an insoluble cross-linked copolymers. Likewise, the "series" method does not apply to manufacture the lithium-containing copolymer of diolefin and aromatic multi-vinyl hydrocarbon applicable as they also contribute to the formation of ice-insoluble crosslinked copolymers leads. The polymer which can be cast at room temperature is made using known methods Practices won. Polar substances such as water or Cl-C5-alkanols can be used Inactivation of the catalyst are added, after which the hydrocarbon solution washed with water or dilute mineral acids.

But you can also use the active polymer solution with hydrated clays (e.g. attapulgus clay), which both inactivate the catalyst and chemically absorb the lithium component. The polymer solutions obtained are filtered and, if necessary, dried and the inert diluent is added elevated temperature (e.g. 70 to 1200Ö) and reduced pressure (e.g. 0.1 to 100 on the Hg) stripped.

The reactions shown below illustrate the various methods of making the polymeric products of the present invention: RLi (polybutadiene) -Lit + (1) butadiene # Divinylbenzene Catalyst inactivation Butadiene-divinylbenzene block copolymer RLi (2) butadiene + styrene # (butadiene-styrene copolymers) -Li + Divinylbenzene Catalyst inactivation Budadiene-styrene-divinylbenzene block terpolymer RLi (polybutadiene) -Li + (3) butadiene # Styrene (Butadiene-styrene mixed polymer) -Li + Divinylbenzene Catalyst inactivation Butadiene-styrene-divinylbenzene block terpolymer RLi (polybutadiene) -Li + butadiene + styrene (4) butadiene Styrene or RLi (Butadiene-styrene copolymer) -Li + Butadiene (Butadiene-styrene-butadiene mixed polymer) -Li + Styrene (if applicable) Butadiene (if applicable) Divinylbenzene Catalyst inactivation Butadiene-styrene-butadiene (styrene) - (butadiene) divinylbenzene block terpoly mer.

To prevent gel formation during storage, the hultivinylaromat, e.g. divinylbenzene, often diluted with a monovinyl aromatic such as ethyl styrene. These mixtures can be used instead of the pure multivinyl aromatics, without that this caused a significant change in the properties of the base polymer will. The component to be encapsulated can with the inventive, at room temperature castable polymer impregnated at about 20 to 120 ° C and the polymer to -.Finally in situ on the component at an elevated temperature in the presence of a or more organic peroxides are hardened. The. in the form of organiæchet Peroxide present hardeners are normally the 'pourable at room temperature Polymer before the impregnation process in amounts of about 0.5. ,, to about 10, preferably 1 to 6 parts by weight per 100 parts of polymer are added. as Peroxide curing agents can include any of those for curing diolefin homopolymers and mixed polymers are used, such as di-tert-butyl peroxide, 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-bis (tert-butylperoxide) -hexyne-3, Benzoyl peroxide, di-tert-butyl diperphthalate, tert-butyl perbenzoate, dicumyl peroxide, Cumene hydroperoxide, 2,4-di- (tert-butyl-peroxyisopropyl) -benzene, tert-butylcumyl peroxide etc. as well as mixtures thereof.

The usual hardening conditions, i.e. 90 to 180 ° C for 15 ' Applied minutes to 48 hours.

Optionally, that can be cast at room temperature Polymer with conventional antioxidants (e.g. 2,6-di-tert-butyl-p-cresol and tert-butyl -hydroquinone), pigments, fillers, etc. are mixed, provided that the total bulk viscosity of the mixture is between 0.05 and 200 Stokes at room temperature.

In the case of industrial impregnation processes, the bulk viscosity of the Polymerisats at the impregnation temperature will normally be 1.0 Stoke or less. As the examples will show, the polymers according to the invention are virtually ideal suitable for such procedures. Compared to the commonly used Temperatures can be the impregnation due to the low bulk viscosities present Polymers actually carried out at considerably lower temperatures will. Conversely, where extremely low bulk viscosities are used for the impregnation are deemed necessary, the polymers according to the invention can be used for impregnation -Temperature of over 1350C can be used, as they do not contain any volatile substances.

The following examples serve to further illustrate the invention. Unless otherwise noted, all parts and percentages are given on weight.

Example 1: This example shows the production of a butadiene-divinylbenzene copolymer with a degree of polymerization of about 20 (DP 20) under one Described nitrogen atmosphere: 2070 g of toluene and 213 g of a 15% solution of n-butyllithium in n-hexane (0.5 mol of n-butyllithium) given. The resulting solution was heated to 40 ° C. and with stirring at this temperature in the course of one hour with 513 g (9.5 mol) of butadiene. While The mixture was stirred for a further two hours at 40 ° C. and 65 g of a 1: 1 mixture from divinylbenzene and ethyl styrene were added all at once with stirring. Man received the reaction mixture at 40 ° C. and withdrew it at various time intervals Fractions as samples. To the.

500 g of sample material with 4-0 to 60 g were obtained in each case natural attapulgus clay, then filtered and the solvent stripped at 100 ° C and 2-4 mm Hg for two hours.

The results are shown in Table I.

Table I: Weight Weight of the bulk viscose or sample time, obtained sity of the ge-sample (gr) (min.) polymer wonn. Polym.

(gr) (Stokes) # A 530.7 5 97.5 0.89 B 476 10 94.5 0.89-0 5Q0 15 88.8 1.29 D 504 30 89.5 4.43 E - 60 135.1 5.00 measured at 25 ° C.

As can be seen from the data in Table I, copolymers can be used with a degree of polymerization of about 20 and a divinylbenzene content of Easily produce 2.5 moles. In particular, it can be seen that samples A and B can be used for impregnation purposes at room temperature, while samples C, D and E at only slightly increased temperature for impregnation are usable.

Example 2: This example uses the procedure according to Example 1, the preparation of butadiene-divinylbenzene copolymerization described with a degree of polymerization of about 20 under a nitrogen atmosphere, namely from: 2070 g toluene, 213 g 15% n-butyllithium in n-hexane (0.5 mol n-butyllithium), 486 g (9.0 mol) of butadiene and 130 g of a 1: 1 mixture of divinylbenzene and ethyl styrene (0.5 mole divinylbenzene, 0.5 mole ethyl styrene).

As in Example 1, the reaction mixture were added at various time intervals the same samples were taken and the bulk viscosities of the polymers obtained therefrom measured at room temperature. The results obtained are shown in the table II compiled.

Table II: Sample Weight Time Weight of the bulk viscose sample (gr) (min.) Polymers n Polymers (gr) (Stokes) + 555.5 5 100.9 0.60 Tabel II (continuation) sample weight time weight of bulk viscous or sample (min.) Obtained sity of the (gr) (min.) polymer recovered poly - (gr) mers (Stokes) + G 473.4 10 82.0 1.65 H 43T, 0 30 80.5 78.0 I 833.5 60 140.9 88.0 +) measured at 2500.

As can be seen from Table II, an aluminum polymer can be used with a divinylbenzene content of 5 mol% without difficulty. In particular it can be seen that sample F is suitable for impregnation purposes at room temperature, while sample G can be used for the same purpose at a slightly elevated temperature is. The big difference between the viscosity values of samples H and I and those of the samples i? and G says that the viscosity of the product by regulation the interpolymerization time can be easily controlled.

Example 3: Copolymers with a degree of polymerization of about 100 were made under a nitrogen atmosphere as follows: In a reaction vessel were 2070 g of toluene and 61.8 cm3 of a 15% solution of Added n-butyllithium in n-hexane (0.1 mole n-butyllithium). The solution was heated to 60 ° C. and added 513 g (9.5 mol) of butadiene over the course of one hour at 60 ° C. with stirring to.

The solution was stirred for a further two hours at 60 ° C. and then up Chilled to 25 ° C. 65 g of 50% divinylbenzene (0.25 mol of divinylbenzene, 0.25 Mol of ethyl styrene) was added all at once with stirring and the temperature was kept at 25 ° C. The same samples were taken from the reaction mixture periodically and as in Example 1 processed. The results are compiled in Table III: Table III: sample weight time weight of the bulk viscosity or sample (min.) Obtained strength of the recovered (Er) min.polymer Soly- (gr) mers (Stokes) + J 472.8 10 89.1 43.0 K 691.7 20 132.9 57.0 L 436.6 30 79.3 94.0 413.6 45 80.0 123.5 496.0 60 107.1 300.0 measured at 25 ° C.

As can be seen from the table above, a copolymer can be used with a degree of polymerization of about 100 and a divinylbenzene content of Produce 2.5 mol% without difficulty. Still there the table III to recognize that the Mischpolymerisa tion implementation are carefully controlled must in order to obtain copolymers with technically useful viscosity values.

Example 4: Some of the copolymers produced according to Example 3 were mixed as follows: Copolymer 10.0 parts of 2,5-dimethyl-2,5-di-tert-butylperoxydhexane 0.2 parts tert-butyl perbenzene 0.05 parts The mixtures were then left for 20 minutes held at 160 ° C, after which a cured rubber compound was present. The properties of the product are listed in Table IV: Table IV: Mixed poly bulk viscosity Shore A hardness of the sample of the mixed polymer cured mixed (Stokes) polymer J 43.0 20-22 57.0 38-40 L 94.0 long Example 5: A low molecular weight Polybutadiene [molecular weight (number average) about 1200] was based on conventional Made by sodium-catalyzed butadiene polymerization. These Polybutadiene sample had a bulk viscosity of about 20 Stokes (measured at Room temperature) and thus complied with the viscosity requirements for impregnation processes.

After mixing this polybutadiene sample with 2 parts of ~ 2,5-dimethyl-2,5-di-tert-butylperoxyhexane and 0.5 parts of tert-butyl perbenzoate per 100 parts of polybutadiene and afterwards However, the material remained cured at a temperature of 160 ° C for 20 minutes of liquid nature and showed only a slight increase in viscosity.

Example 6: Polybutadiene was made by polymerizing butadiene with an n-butyllithium catalyst prepared by the method of Example l. No multivinyl aromatic hydrocarbon was used.

After the end of the homopolymerization, the reaction mixture became with treated with natural attapulgus clay, filtered and for the recovery of polybutadiene stripped in vacuum. The polybutadiene thus produced had a molecular weight (Number average) of about 1000, a degree of polymerization of about 19 and a bulk viscosity of about 1.3 Stokes (measured at room temperature).

This polybutadiene sample was then used. according to mixing instructions and curing conditions of Example 5 cured, but the cured material remained of flü ger consistency 'and showed only a slight increase in viscosity.

Comparing the results of Examples 5 and 6 with those of Example 4 shows, a low molecular weight "base polymer" like this arises from sodium or alkyllithium catalysis, has a reactivity, which is insufficient for its use in encapsulation processes. Although this Homopolymers have suitable low bulk viscosity values, so cure they - in contrast to the erfindungsge ', moderate copolymers' (see. Example 4) but not too rubbery masses, as required for encapsulation processes is.

Example 7: A low molecular weight, high grade polybutadiene 1,2-linkage under a nitrogen atmosphere was made as follows: In a reaction vessel were 630 g of n-heptane, 202 g (2.8 mol) of tetrahydrofuran and 120 g g of a 15% solution of. n-butyllithium in n-hexane (0.28 mol n-butyllithium) given. The resulting solution was stirred at 25 ° C. and continued over the course of one hour Add 300 g (5.6 moles) of butadiene. The mixture was stirred at 25 ° C. for a further two hours and then the catalyst by adding 100 cm3 of water deactivated. The heptane solution was washed with water until the wash water responded neutrally to litmus. Then it was dried over anhydrous MgSO4 and filtered and the solvent was for two hours at 1000 C and 2-4 mm Hg stripped.

The polymer obtained had a molecular weight (number average) of 1000 (determined by vapor phase osmometry) and a viscosity of 378 Stokes (measured at 25 ° C) and had a 90%, 1,2-vinyl structure (determined by Infrared spectroscopy).

It follows that low molecular weight polybutadienes with high Share of 1,2-vinyl structure not required for solvent-free encapsulation, Required low bulk viscosity owner.

Example 8: Sample J of Example 3 was mixed with 2.5 parts of 2,5-dimethyl-2,5-tert-butyl-peroxyhexane and 0.5 part of tert-butyl perbenzoate per 100 parts of copolymer. With the mixture (a total of 20 parts) was 75 parts of sand with a clear mesh size from 0.833 to 1.651 mm (Tyler) using conventional methods such as those used in industrial Impregnation process used, vacuum-impregnated. It was determined, that the sand could be quickly impregnated with the mixture at room temperature. the composition filled with sand was about 75 minutes at 160 ° C cured to a Shore A hardness of 70 to 50. It follows that the novel polymers according to the invention for the impregnation of sand-filled apparatus, like solid state transformers, are very suitable.

Example 9: Following the procedure of Example 1, a Butadiene-styrene copolymer by polymerizing a monomeric mixture 410 parts of butadiene and 198 parts of styrene at about 40 ° C in the presence of about 2070 Parts of an inert diluent such as toluene and 213 parts of a 15% Solution of n-butyl lithium in n-hexane shown. The base copolymer produced in this way normally contains about 80 MolO monomeric butadiene units and 20 slold; mono - mer styrene units. The resulting solution became about 65 g of one at a time 1: 1 mixture of divinylbenzene and ethyl styrene added and the terpolymerization took place for about 5 to 100 minutes at 40 ° C. After working up the reaction mixture with natural attapulgus clay, filtering and vacuum stripping one obtained Terpolymer with a bulk viscosity of 15 to 100 Stokes (measured at Raum -temperature; the actual bulk viscosity in each case depends on the period of time which is attributed to the terpolymerization). The hardening of a mixture of this Terpolymers with the Perox, yd approach and under the curing conditions of the example 4 gave a gummy mass with a Shore A hardness of 15 to 45.

Example 10: A butadiene-styrene copolymer was at 2500 below a nitrogen atmosphere prepared as follows: 4,590 g of toluene and 1700 g of a 15% solution of n-butyllithium in n-hexane (4.0 mol n-butyllithium) given. The catalyst solution kept under stirring became in the course one hour simultaneously with 3,256 g of butadiene (60 mol) and 1,664 g of styrene (16 mol) added, continued for four hours and then deactivated the catalyst by adding water. The polymer solution was prepared as in Example 7.

The copolymer had a molecular weight (number average) of 1200 (determined by vapor phase osmometry) and a viscosity of 25 Stokes at 2500.

A sample of this interpolymer was prepared using the procedure and curing conditions of Example 5 cured, but the material remained liquid and showed only a slight increase in viscosity. It follows that by alkyllithium catalysis manufactured, low molecular weight base copolymers, although one for solvent-free Encapsulation have suitable bulk viscosity, but that they are not too rubbery Curing masses as required for encapsulation processes is (as there is no aromatic multivinyl hydrocarbon present).

Example 11: This example describes the production of a copolymer having a degree of polymerization of about 105 under a nitrogen atmosphere: In a reaction vessel was 2070 g of toluene and 61.8 cm of a 15% solution of n-butyllithium given in n-eexane (0.1 mol n-butyllithium). The solution was heated to 600C and added 203 g of butadiene (3.75 mol) over half an hour with stirring. Stirring was continued for one hour and then styrene in an amount of 260 g (2.5 Mol) styrene added with stirring. An additional hour at 60 ° C was allowed and then a further 203 g (3.75 moles) of butadiene in the course of a half Hour added. After the addition, stirring was continued at 60 ° C. for a further hour. The solution obtained was cooled to 2500 and mixed with 65 g of 50% divinylbenzene (0.25 mole divinylbenzene, 0.25 mole ethyl styrene) by adding them all at once offset. The mixture was stirred for a further 20 minutes at 25 ° C. and then the polymerization reaction was stopped by adding natural attapulgus clay. After filtration and solvent separation gave a polymeric product with a bulk -Viscosity less than 75 stokes at 25 ° C.

If the product is prepared according to Example 8 and 75 Cured minutes at 160 ° C, then the cured composition has a Shore A hardness from 30 to 50 on.

Like this example, it can be hardened and at room temperature Pourable terpolymers of butadiene, styrene and divinylbenzene through one another - Subsequent addition of butadiene and styrene and subsequent final addition of divinylbenzene getting produced.

Claims (8)

Patent claims: 1. Polymer of an aromatic multivinyl hydrocarbon which copolymerizes with a diolefin homopolymer or a copolymer terpolymerized from diolefin and aromatic monovinyl hydrocarbon, characterized in that the mixed polymer is in practically solvent-free form has a bulk viscosity of from 0.05 to about 200 Stokes and as a block copolymer is present and that, based on the number of monomeric units in the homo- or mixed polymer, the multivinyl aromatic hydrocarbon is present in an amount up to 10 mol / o is. 2. Copolymer according to claim 1, characterized in that the diolefin is a C4-C6 conjugated diene. 3. Copolymer according to Claim 1 or 2, characterized in that the aromatic multivinyl hydrocarbon has 10 to 40 carbon atoms and the general formula has, in which Ib has an aromatic nucleus. and R1> R2, R3 and R4 independently of one another are a hydrogen atom, C1-C12-alkyl groups, C1-C12-cycloalkyl groups or vinyl groups. 4. block copolymer according to claim 1 to 3, characterized in that the aromatic lilonovinyl hydrocarbon has 8 to 40 carbon atoms and the general formula having; in which # is an aromatic nucleus and R'2, R'3, R'4 and R '5 are, independently of one another, hydrogen atoms, C1-C15-alkyl groups or C1-C15-cycloalkyl groups. 5. block copolymer according to claims 1 to 4, characterized in that that the diolefin 1,3-butadiene, the aromatic multivinyl compound divinyl benzene and the IV ionovinyl aromatic hydrocarbon is styrene. 6. Copolymer according to Claims 1 to 5, characterized in that that it is at an elevated temperature in the presence of at least one organic peroxide has been hardened. 7. Process for the production of copolymers after -den claims 1 to 6, characterized in that (a) a diolefin in one Temperature from 0 to 100 ° C with 0.005 to 0.2 moles per mole of diolefin of one essentially An organolithium compound catalyst of the general Formula RLi, in which R represents a C2-C20 alkyl, aralkyl or cycloalkyl group, brought into contact, (b) the lithium-containing polydiolefin thus obtained with up to 10 moles of multivinyl aromatic hydrocarbon by number monomeric units in the polydiolefin, at a temperature of -30 to + 500C brought into contact, and (c) inactivated the catalyst and the block copolymer is isolated from the reaction mixture. 8. A process for the preparation of copolymers according to claim 1 to 6, characterized in that (a) a lithium-containing block copolymer from diolefin and aromatic monovinyl hydrocarbon by (1) at 0 to 100 ° C contacting a diolefin with 0.005 to 0.2 moles per mole of diolefin one organolithium catalyst of the general formula RLi, in which R is C2-C20 -Alkyl, -aralkyl or -Cycloalkylgruppe, and conversion of the lithium-containing group obtained Polydiolefins with an aromatic monovinyl copolymer, or (2) at 0 to 100 ° C taking place contact of a mixture of diolefin and aromatic lhono -vinylkolenwasserstoff with 0.005 to 0.2 mol of the organolithium catalyst, based on the total number of moles of diolefin and aromatic iono-vinyl hydrocarbon, produced, and (b) the lithium-containing block copolymer thus obtained with up to 10 mole percent multivinyl aromatic hydrocarbon based on the total monomeric units in the copolymer at a temperature between - '»0 and + 500C brought into contact, as well as (c) the catalyst is inactivated and the solvent-free Block terpolymer is isolated from the reaction mixture.