DE1745266A1 - Method and device for the production of polyethylene at high pressures - Google Patents

Description

Patent application

aes Mr. Dipl. «Ing. Friedrich Prochnow v.einheim / Bergstrasüe, Oberer Sandweg 6

Method and device for the production of polyethylene with high backs

ii8 began to produce l ^ olyaethylene at high pressures uses a process and apparatus in which catalyst-free ethylene is continuous flows through a Kings can space, aer between a thick-walled high-pressure tube as the outer tube is formed una a thin-walled inner tube. This catalyst-free ethylene of the annular gap tube takes as Cooling medium part of the exothermic «poor, which is in the inner tube space during polymerization after entry of the ethylene in the inner tube heated to the light-off temperature when the catalyst is fed in.

In this procedure, the various options were available the implementation, the regulation etc. successfully tested, so z. B. the reverse driving style, namely that the catalyst-free ethylene, which flows through the inner tube and serves as a cooling medium, the heat of reaction that is formed during the polymerization in the annular pipe space, partially absorbs, or, for example, that the feed Aegezweigter substreams of catalyst-free ethylene takes place at points of the annular gap tube, if

ßAD ORIGINAL · 109833/1595

ζ. B. in this the polymerization is carried out.

With this new process, in contrast to the known processes in tubular reactors, it has proven to be extremely advantageous and, in particular, decisive for the course of the polymerization, that gaseous catalysts, for example oxygen, under no circumstances be mixed with ethylene, long heating pipe sections of copper. Do not run through 55 ⁰ C up to the initial temperature of the polymerization, except that, according to the process, the catalysts are: the bark of a straight pipe section and, at the beginning of a curved section of the reactor pipe, are brought into the flowing, catalyst-free ethylene, which is heated to the initial temperature of the polymerization, The catalyst-free ethylene and the catalyst and / or negator and / or moderator are fed into their own feed lines at one or more points of the keuKtors, and in the event that the catalyst and / or additives are fed in, it is useful to design the feed that the catalyst is entrained or sucked in by the flow rate ues catalyst-free ethylene by suitable shaping of the catalyst feed line within the Aetnyien-Zufohrungsrunres.

It was surprisingly found that it is more angular is that the catalyst-free ethylene and the catalyst possibly in combination with Hegler and / or moderator, in one or more feed points of the double tube reactor depending on whether the polymerization tube is the inner tube or the canister tube, in its own way Feed lines flowing into the Kohrreaktor, wherein

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the respective Einspei8ungsstelle is preferably in a straight pipe section, from which in the same gas flow direction of the Keuktionspartner the heated to the ring temperature is polymerized, if you continue according to the invention by suitable measures such . B. a short pipe constriction ensures that a & ss exactly at the feed section for a catalyst etc. briefly an increased ethylene leakage rate combined with a corresponding pressure reduction occurs, once the catalyst feed without the hitherto necessary and costly / unnecessary pressure increase compared to other Aethylene urucic in the lieaictor take place, and on the other hand, the formation of a "vOlyaetnylenbelag" in the feed area is excluded. Jjurch structural masonry on the narrowed pipe, ζ. Β. Inclined ribs or grooves in the constriction can advantageously be achieved by swirling the ethylene-catalyst mixture. The artificially generated pressure reduction, which is advantageous for feeding in the catalyst, is also beneficial after the start of the polymerization due to the effect of the known drop in reaction pressure, which with the onset of polymerization proceeds proportionally with the catalyst consumption reaction and causes the subsequent flow of ethylene and catalyst into the reaction center during operation The natural pressure reduction in the iteuCtion range can also be used to feed the catalyst without reducing the pressure.

Through the invention, artificial and / or natural .Let use of the pressure minimization in the leakage pipe Disadvantages with which the known methods

109833/1595 pad ORIGINAL.

are olyaethylenherstellung to x ^J afflicted in .Röhrenreaktoren how extraordinarily large operating uncertainty York Convention susceptibility, low levels of revenue, among other things, avoid. In the known KÖhrenreaktorverfahren is known to migrate the polymerization reaction after a few hours of operation because of the formation of polya ethylene; Wall lies at the end of the heating-up zone and at the beginning of the reaction zone, i.e. in front of the reaction center, steadily in the rear core pipe sections, and the heating center itself is simultaneously shifted to the rear sections of the reaction zone. According to the method according to the invention, in contrast to the known method , the activity center no longer migrates due to the lack of the ro lya ethylene - »« anübel age in front of the iteaiction center.

When carrying out the process, the .catalyst, possibly together with Hegler and / or Luüderator, in the through suitable measures, but without going through a long preheating zone, heated to a ring temperature, Catalyst-free ethylene sucked in the direction of flow, so that the polymerization just behind the Point of introduction of the catalyst in the tubular reactor begins. The resulting polyethylene is from the unreacted ethylene in the gas stream, after the for this with of the short-range Hohrqu cross section reduction apply ot flow laws, steadily driven away. The constriction must be designed and dimensioned so that the outflow Ethylene-x'olyaethylene mixture by no means Passing through the constriction and flowing into the keak

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tion zone, left the original ear cross-section: sits, comes into contact with the pipe walls, whereby the formation of polyethylene coverings remains excluded, which as mentioned in the known processes especially at the end of the heating zone and at the beginning of the reaction zone always appears in front of the reaction center and is the cause of procedural difficulties and degradation. The work-up of the ethylene-polyethylene mixture and the recirculation of the jiricectsaethylene takes place in the usual way, but worth mentioning is that you can dispense with the ^ usual intermittent relaxation at the end of the reactor and the iteactor pressure z. B. by an adjustable Keeps the opening cross-section constant at the end of the reactor. The volyaethylene produced is of excellent homogeneous Quality, tti.e allows every processing option and. to be used for all purposes is.

Possess by additives to the catalyst-free ethylene and / oüer to the catalyst, preferably one hand polyaethylenlösende within the temperature and pressure range of the .Polymerisation Eigenscnaften and on the other hand, the ethylene-decomposition temperature up set, * m ^ n continue to beeinfluaden low able to erfinaungsgemässen iOlymerisutionsaDlauf and to pay. Every possible quality of olyaethylene can be produced in this way.

The invention experiences a further development of this process by the quickest formation of

109833/1695

sufficiently effective free radicals in predetermined Temperature ranges not only triggers polymerization, sufficient polymerization rates achieved and aie chain reaction of the polymerisation of Ethylene in the so-called burner zone is operationally safe and trouble-free in (lasts for a long time, but the various variable high quality Polyaethylentyoen each same quality and properties and also ethylene. iuischpolymerisaten with other copolymerizable Monomers, such as. B. butadiene, Lityrol achieved. This is achieved according to the invention in that one

^ suitable catalysts initiated by suitable irradiation, preferably by means of gamma rays or hard X-rays or neutrons in such a way that, in particular due to the surprisingly enormous shortening of the half-lives of the catalysts, the polymerization of ethylene in the burner zone takes place simultaneously with the irradiation. Pur this formation of free radicals takes place according to the invention, in addition to the known i'eroxide and azo compounds, oxygen or ozonated oxygen at higher temperatures, e.g. B. 165 ⁰ C to 185 ⁰ C, as a suitable catalyst use, namely by the fact that oxygen in the supply of radiation activation

'energy is also enabled for the immediate education of free radicals. The number of temperature, pressure and reaction participants, possibly also of the reaction medium, within the scope of the protection request is determined by the desired properties, such as density, molecular weight, melt index, processability as well as transparency, flexibility, etc. whose foils should have.

^109833/1595 ** _OomiNAL

According to German patent 914 434 and German, ⁰ C and pressure tables 50o and 4000 atmospheres and on the other hand at temperatures of 10 to 30 ⁰ C and pressures of HO to 200 atmospheres can polymerize. In these processes, however, the space-time yield and all conversions of ethylene to roly-ethylene are extremely unsatisfactory. After erfindiui ^ sgemässen process, preserving, however, thanks uer surprising increased efficacy four catalysts by irradiation, high-KaumiJeit exploit and ir'olyaethylen per throughput high sales ύοπ ethylene zxx, una succeeds homogeneous Polyethylene same quality in different density and To produce molecular weight ranges, namely by not only choosing different catalyst concentrations at the feed parts into the flowing ethylene, but also bringing the initial temperatures into agreement with the catalyst quantities and the reaction pressures and, above all, the energy content and the energy quantity of the respective type of radiation varies. According to the invention, as already described, the irradiation does not serve to irradiate the large amount of ethylene, but rather to initiate the small amount of catalyst. For example, in the inventive polymerization of ethylene in the presence of the usual amounts of oxygen as a catalyst, hydrogen as a chain growth regulator and isobutane as Mouer tor at a reaction pressure of

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"2100 atmospheres and a temperature of 200 ⁰ C in the burner zone of the polymerization catalyst for initiating aes for example with gamma rays with an energy content of 1.25 MeV at a dose of 0.5 Höntgeneinheiten per second;. According to the invention it is also possible with high-energy radiation sources and work with higher radiation levels.

It is also very surprising that in the inventive Process. The amounts of catalysts, based on the amount of j-ό lya ethylene produced, are lower than is the case with the known letterpress printing process.

The process according to the invention operates in such a way that pressures between 500 to 5000 atmospheres, preferably from 2000 to 2500 atmospheres, at temperatures from 100 to 300 ^° C., preferably from 160 to 240 ^° C., one or more of the known ones, are used Catalysts in a mixture with one or more of the usual regulators together with or without one or more of the known moderators in one or more feed points of a tubular reactor in one or more separate feed lines in the same direction of flow in the catalyst-free ethylene, which is heated to the starting temperature, flows in such a way, that the catalyst, with or without additives, is metered into the flowing ethylene by reducing the pressure by means of a narrowing of the reactor tube cross-section in the area of the respective suction point, and after the polymerization has started, by subsequent flow of

^109833/1595

further, no longer heated fresh ethylene and the sufficient amounts of catalyst, with or without additives, the polymerization of ethylene at the focal point polymerisation triggered is kept going, where appropriate, .eise the respective radiation source ζ. B. for gamma rays radioactive cobalt 60 in the Zone in which the previously heated catalyst-free ethylene and the catalyst with or without additives meet and mingle as appropriate - that the short-wave electromagnetic rays are concentric the catalyst flow initially in the feed line and continue to penetrate in front of and in the burner zone, to initiate the catalyst molecules in such a way that the free radicals formed in the formation state, as it were, act as seed radicals, the chain reaction tier ethylene polymerization and this through the practically constant initiation of the incoming catalyst is able to keep going steadily. That continuously accruing xteaktionsgut is known in The unreacted ethylene, if necessary after a previous purification, of the reaction is relaxed fed back and the obtained ^ olyaethylene, also as usual, worked up.

The heat of formation released during L ^J olymerisation is absorbed by the ethylene-x flowing off ^; olyaethylene added. If an excess of heat remains, this is achieved through an indirect heat exchange by passing the ethylene to be polymerized through a second pipe of the reactor system or through another type of heat exchanger.

109833/1595

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The inventive proceeded sees the Müglichicuit ago, the former, while the whole i-olyiaerisationsverlaufes always on the Ans vv ingtemperatür done heating up to dispense of ethylene. The icatalyst-free ethylene is only briefly heated for delivery to the temperature required for the polymerization, e.g. B. by electrical heating of a short pipe section, and combined with a catalyst, for example oxygen, and / or negator and / or moderator, if the polymerization begins, the heating is switched back; Cold ethylene and analyzer meet in a suitable device, preferably in a bunsen-like or welding torch-like design, and keep the polymerization on record in a "burner-one". The heat released during the polymerization is carried away by the ethylene which has not been used. Me conversion level is limited upwards by the amount of catalyst, which in turn depends on the Jibeosungen of the keactor

According to the invention, it is possible in a Kohrreactor to allow several burner zones to become effective and, depending on the number, to select suitable products «Ejecting them separately, or the reaction good Mix the first with that of the second or the other burner zones and in the usual way. «ice relaxation, ethylene recirculation and polyethylene processing perform.

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One can know this process according to the invention also in a reactor combination of double tube, Polymerize conventional tube and autoclave reactor.

It was also determined that suitable measures can be taken to control the need for heat dissipation in all parts of the reaction zone, preferably in the area of the maximum temperature increase, by using catalyst-free ethylene, which serves as a cooling medium, regardless of whether this is the annular space or the inner pipe either optionally in cocurrent or in countercurrent flow Λ 'aurchfliesst it ut-to btromungerichtung aes Heaktiuns ^, on a OAER .vorzugsweise at several adjacent positions of the relevant tubular wall aurch üeffriungen »z. B. are provided with outflow nozzles or nozzle-like constrictions, flows directly into the flowing polymerization mixture without supply lines. "'·." -

This inventive method not only has the advantage of the exothermic i ^J olymerisationswärme from the endangered reaction zones reliable and aozuführen it easy to V.ege but unlike the oeicann- * th process, it is möglieh, the supply of compressed cold Aethyien into the flowing High-pressure polymerisation mixture at reaction pressures between 1500 and 4000 atmospheres without expensive precision pumps of a special design. The natural pressure reduction prevailing in the action area is converted into cold gas

1098 33/1695 bad original

introduction exploited una Namely, the maximum allowable j-'olymerisationstemperatur preferably \, _s i on eini ge few degrees higher than the notwendige- i-olymerisations light-off temperature, for example Dei oxygen as il-italsysator of about 190 ⁰ C, flowing in through aas lowered.

Lie invention further provides the supply of the gaseous, preferably of the catalysts in solution, with ouer no known chain growth regulator and / or .bekannte iüoaeratoren, advantageously in adjacent utellen to aen aforementioned openings for aas Cold ethylene in otrömun _r srichtung aes neaktionsgemisches by the combined effect of the known natural reaction pressure drop, increased ethylene flow rate and the artificial through the restrictions in the xialtaethylenöffnungen generated pressure impairment, so that the catalyst in addition to the named additives to flow as it were automatically without iümpenkraft in aas new ethylene-i ^J olyaethylen mixture and aie i'olymerisation of the inflowing cold ethylene and keep this in motion until the end of the catalyst consumption reaction. The flow velocity in the reactor must be 1.5 m / sec. not fall below.

The cold in the inflowing keaktionsgemisch Aethylenmenge with temperatures of preferably between 20 and 50 ⁰ C is olymerisationsteimeraturen-i directly related to the üenicungen aer. If there is a desire to have ile sales of Ac-thy len; olyaetnylen by j.'polymeri-

109 8 33/1595 BATHROOM _{OFTEN iGmÄL}

sations of the cold To increase the amount of ethylene, so is the amount of ethylene flowing in directly determining the strength of the catalyst to be introduced and indirectly determining the lowering of the Polymerization temperature, which is known to be of the type of the Xaxalysator, boiler and control technology Are these interdependent parameters taking into account the other variables, such as flow velocity, Dwell time, reactor diameter, lleaictorlange, reactor volume, etc. , preferably for the possible variations of the polymerization process and the required polyethylene materials, i <molecular weight widths and the like, recovered.

In general, the process according to the invention is used carried out in such a way that after an initial process of polymerisation and again reaching the maximum permissible temperature to kill the educational worms cold ethylene flows in automatically, likewise in this V.'repeatungsfall ii catalyst, if necessary also the mentioned Hegler and / or moderators. the Flowability of the resulting folyaethylene-ethylene mixture, those with a higher polyethylene content Easier to form and more difficult in the operating state iOlya-ethylene coatings to be removed from the reactor walls and limit the steadily yielding V. value of the pressure drop the number of polymerizations of cold ethylene and thus also the level of conversion.

10 9833/1595 teAD

example 1

By an i-Olymerisations- ^ uppelrührsystem flow continuously at a .ivruck of 2300 atmospheres per hour 20 OOü Gev, i ts parts tü-Italy sator free A len, uas upon entering the heated on 2ϋυ ⁰ C itean.-tion zone from a separate supply line a mixture of 3½ ppm oxygen (= 3 parts by weight of oxygen per one million parts by weight of acetylene), 0.2 parts by weight of 3 parts of hydrogen and 350 parts by weight of ßenzene-saturated isobutane, after flowing through an upstream jieeactor tube constriction, sucks in the resulting pressure reduction Termination of the oxygen consumption reaction at the end of the burner zone follows. The known relaxation and in the downstream high-pressure stripper a separation of the generated x'olyaetnyiens from the unreacted ethylene-hydrogen-benzene-isobutane mixture, a proportionate, the initial concentration corresponding Quantities of ethyl alcohol, water and benzene-saturated isobutane are added to this mixture. Is fed to the renewed polymerization, we receive 4-150 parts per hour of x-olyaethyien with a melting index of 1.5 and a density of 0.922.

The x-olyaethylene obtained can be processed very well and hex-divided blown films are distinguished by excellent transparency, flexibility and surface brilliance from as well as due to improved strength properties.

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Example 2

In a high-pressure double-tube polymerization system, the ^{catalyst-free ethylene, which is compressed to a reaction pressure of 2100 atmospheres and heated to 1Ö5 0} C, sucks in a mixture of 20 ppm oxygen (= 20 parts by weight of oxygen per million parts by weight of ethylene) and 0.1 part from a separate feed line ., 'Asserttoff together with 1.5 parts of benzene-filled isobutane, in each case based on 1000 parts of fresh ethylene, so that before the catalyst-regulator-aerator device emerges from the supply line it is produced by gamma rays from a cobalt 60- Source with an energy content of 1.25 MeV and a dosage of 0.25 Roentgen per second has already been initiated, so the polymerization begins shortly after the maximum reactor tube constriction and the discharge point of the mixture and is located in the elongated burner zone in the xieaictor, which is also still through gamma rays, continues until the permanent consumption reaction has ended. After the start of the polymerization, only heated fresh ethylene flows in continuously. The flowing ^ethylene-i> olyaethylen-Ge; .. ish the Bilaungswärme absorbs.

The polyethylene produced is a high-quality material that can be used for all relevant purposes can be used. .

Example 3

To further explain the invention, the following shows

1 098 3 3/159 B

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standing example of iiana of a scientific drawing an embodiment of the inventive idea for carrying out the process.

The drawing shows schematically a combination of three high-pressure reactors, each of which can also be used individually to carry out the process, if necessary several can be connected in series or in parallel an inner tube (2) of equal length with a clear diameter of 31 mm, the catalyst-free ethylene through the line (4) as a coolant through the between the outer wall of the thin-walled inner tube (2), which in this example serves as a heating tube, and one between the Outer wall of the thick-walled high-pressure pipe (1) with a clear passage of 5 mm in the same direction as the ethylene to be polymerized through the combined lines (3 and 3a) entering the inner pipe space and in the course of the polymerization at several points through separate lines (6a ) or through openings (6b), preferably e in the area of greater temperature differences between reaction mixture and cooling medium, with prischaethylene flows into the reaction space. The catalysts and additives, such as solvents, bowlers and / or judges, are fed into the flowing ethylene through associated lines, depending on their composition or composition. In this embodiment of the process, the catalysts and additives are used

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through the lines (5) and the two lines (7) brought in. The inlet lines (5), (6a) and (7) and the openings (6b) are each preferably located on find an arc and end in the direction of the flow direction of the ethylene. Three short-haul Constrictions (8) of the inner tube (2) on the catalyst feed parts 3 are with inclined ribs or grooves. -

In this example, the polymerization in the double tube reactor is followed by a high pressure tube reactor (10) without a

Clear cooling jacket about 120 m long and 50 mm Diameter. This reactor tube is provided with four tube constrictions (8). The analog feed-in points for the catalyst and the usual additives also run in the direction of flow of ethylene, and the lines (5) and (7) for the introduction of the the same catalyst and / or additives in each case have nozzle-like configurations at the end. The ethylene-polyethylene mixture passes through line (11) and the ethylene through lines (3) and (3b) as well (6a) sin into the reactor.

This polymerization is followed by the downstream I

Polymerisatton in an upright autoclave reactor (17) of about 10 m length and a clear diameter of 300 mm with a suitable stirrer. Drive (18), agitator shaft (19) with agitator (20), for example Schaafelartlg, the reaction material in the upper part of the reactor, only slowly in the lower Autoklnventeil

109833/1595 ■ 'BAD OFMGINAL'

Let ana sink in this part of the container by means of increased Ktihrurganzuhl Jas achieve the desired effective leads to ensure the liomogcni Ut of the polymer and the safe flow of oil to achieve the oil through the line (21), into the autoclave chamber aas Aetnylen- The ethylene ethylene mixture through the line (16) and the primary cycle ethylene through the combined lines (3) and (5c). Mixing is achieved by means of suitable odoriferous food, e.g. B. uurch Regenstrommasöigeκ tangential tinstrümen. The catalyst in! (Earring ;. (^ occurs aurch the lines (5) and (7), for example, each via a distributor, 4) various Great one, lie ausenartige i / urchbon- wrestled in ütrdoiungsrichtung aes, te tnylens own. Also, this reactor (17) as well as the iot: tüuKtor (10) una uer double tubular reactor: ait appropriate as- me and itegelgeraten auo _£ _, erastet such v.ie ü distributed with but aie temperature zones iemperatur-iiletiageraten the ongoing Deberpr-.. It is used for the production of specific polymers with characteristic temperature profiles.

The air, which is compressed to 150 atmospheres and heated to the ana print temperature, first flows through the inner tube (2) of the double tube reactor. B. a for the Ani; tem.jeratur suitable bekaiinten free na..ikale bLlaeruien a catalyst, the; _e orin

ORiGiNAu

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.-. 19 -

in a roly-ethylene-free liquid with Mocieratorwiri-ung is yellow, like.ζ. Β. Benzene or cyclohexanes

jV-vs. oxygen is supplied as a catalyst while a catalyst-free ethylene in the outer tube (1), heated by the i-polymerization warine, flows through the line (4), if necessary after passing through known heat exchangers, via distribution points into the inner tube (2) -ale- line (9) Uas j'polymeris5? j tion mixture preferably: a with tangential inlet into a separating vessel (22a), in which part of the unreacted catalyst-free ethylene, preferably through aie line Oa) in the oil circulation in the inner tube aes Boo ^ Blrohrreaktors is fed back. From the reaction mixture passed through the lower outflow of the separating vessel, a part can optionally be withdrawn through line (12) and worked up in a known manner to a special i'ölyaethylene type and the ariaeren part through line (11) in the nohrreaktor (lü) i'unren, which is also under the compression pressure of 25ÜÜ atmospheres, minus the previous pressure loss, in a this heater repeated suction of the catalysts through lines {5) and (7), the introduction of ethylene through the pipes (3 plus 3b) and (6a), and the like kbfluss * tion of Hea! sehes through the conduit (13) in uas Tr.ehn _£ efass (22b) analogously from the AEM Trenngefass (22a) respectively the Gus Product discharges (3b), (14), (15) and (16) take place.

10 9 8 3 3/1595 bad original

The flow velocities in the elongated reaction zones of the tubular reactor are to be selected in a suitable manner so that the polymerization temperatures correspond to the specified temperature profiles. Composed of the lines (16), (3 plus 3c) and (6a) in the stationary reactor vessel (17) - which is also under the compressive pressure of 2500 atmospheres, minus the previously occurred pressure loss - introduced ethylene-Polyaethylengemisch and Frischcethylen is by means of the catalysts as in the earlier reactors from lines (5) and (7) in a suitable manner, for example with the aid of the nozzle-like bores in the annular tubes (24) and the stirring device (18, 1,9, 20), ζ. B. with blades, polymerized in the usual way. The reaction material flows through line (21), preferably tangentially into a separation vessel, for the purpose of pre-separating the unreacted ethylene, which is returned to the gas cycle through line (3a). The polymerization mixture flowing out through line (23) is depressurized in a known manner in a one- or two-stage process and worked up as usual.

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Claims (1)

Pat . Process for the production of polyethylene at high pressures, characterized in that the kstalysa '* gate-free ethylene and the catalyst, optionally mixed with a regulator and / or Moderr.tor, in one or more feed points of the double-tube reactor, optionally whether the polymerisation tube is the inner tube or the annular gap pipe, flows into own Zufiihrungsleitungen in the tubular reactor, with the respective feed point is preferably in a straight pipe section from the same C ta direction of flow of the reactants the mixture was heated to the starting temperature ethylene is polymerized from. 2. The method according to claim 1, characterized in that that catalyst-free ethylene, drs as a cooling medium is passed through the cooling system of a double tube reactor, through openings in the walls of the reactor. onsrohres, preferably in the area of greater temperature differences between the reaction mixture and Cooling medium, possibly with nozzle-like constrictions, flows into the reaction mixture. 3. The method according to claim 1 and 2, characterized in that that the catalyst in the flowing ethylene by pressure reduction by means of constriction of the reactor tube cross-section is metered in in the section of the feed point. BATH 1098 33/1 59 5 4. The method according to claim 1 to 3, characterized in that that for feeding in the catalyst, the pressure reduction in the reaction center is optional is used with / without an upstream artificial reactor tube constriction. 5. The method according to claim 1 to 4, characterized in that in adjacent locations to the Openings for the Kaltaethylene catalyst, possibly regulators and / or moderators, automatically flows into the reaction mixture, 6. The method according to claim 1 to 5, characterized in that the ethylene to be polymerized Substances themselves and / or in a mixture with the catalyst adds, on the one hand within the Temperature and pressure range of the polymerization have polyethylene-dissolving properties and on the other hand raise the ethylene decomposition temperature. 7. The method n> ch claims 1 to 6, characterized in that that after the onset of polymerization, this cannot be done by merging the light-off temperature of heated fresh ethylene and the usual amounts of catalyst in the fire point the initiated polymerization keeps going. 8. The method according to claim 1 to 7 »characterized in that that the catalyst-üinspeisungsstrom in the flowing catalyst-free ethylene gamma rays, X-rays or neutrons. ^BATH 1098 33/1595 9, method np.ch claim 1 to B, characterized in that that, regardless of the design of the reactor, the polymerization can be carried out in a reactor combination z ". B. consisting of a double-tube reactor, a known high-pressure tube reactor and an autoclave reactor. 1ü «device for carrying out the method according to Claims 1 to 9, consisting of high pressure reactors, which preferably consist of straight pipe sections and are composed of arcs and can be combined into several parts connected one behind the other or in parallel, each ™ High pressure reactor consisting of an outer tube and a inner tube of equal length beat.eht, characterized j that for the supply of the ketalysator-free Ethylene and the catalyst one or more feed points (5, 6a, 6b, 7), preferably on Provided at the beginning or at the end of a straight pipe section and its own nozzle-like at the end of the line trained supply lines to the inner pipe • which are built into the annular gap pipe. 11. The device according to claim 10, characterized in that is connected to the working with cooling double ä tube reactor (1, 2) optionally, a known high pressure tubular reactor (1O) and optionally then a likewise known per se autoclave reactor (17), said analog the arrangement of feed points in the cooled double-tube reactor also includes feed lines 1098 3 3/1595 ^c BAD (5f 6a, 7), which em end nozzle-like formations have, are provided. Friedrich Prochnow 109833/1595