DE2119305A1 - Process for the polymerization and for the copolymerization of monomers with olefinic double bonds - Google Patents

Description

sue · C-oeeUgietL i / Caesieai ~ * 1

PATENT ADVOCATE

April 17, 1971 Application files: 75,320

Applicant: Ceskoslovenska akademie ved, Praha

Title: Process for the polymerization and for the copolymerization of monomers with olefinic double bonds

Isobutylene is one of the industrially most interesting monomers, the polymerization of which proceeds with a cationic mechanism. In commercial practice, the high molecular weight polymerization is usually catalyzed with aluminum trichloride or boron trifluoride, and performed at low temperatures of about -80 to -100 ⁰ C. Because of their high reaction rate, the polymerizations cannot be carried out without solvents or in highly concentrated monomer solutions without the heat of reaction leading to undesirably severe overheating of the mixture, even with intensive cooling and stirring. Therefore, one works in solutions with lower concentrations and thus with considerable solvent volumes, which are recycled for purification purposes. The necessary low polymerization temperature and the purification of the auxiliary solvents increases the costs of the equipment and makes the production process of the high molecular weight polyisobutylene more expensive.

The best-known isobutylene copolymers are aeine Copolymers with isoprene or butadiene. In the technical

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The high molecular weight copolymerization of isobutylene is in practice to butyl rubber carried out at low temperatures around -80 "to -100 C. The catalysis is usually carried out with Aluminum trichloride or boron trifluoride. At higher temperatures, copolymers with lower molecular weights are formed, which are therefore not suitable for further processing by vulcanization. Because of the fast response time the copolymerizations cannot be carried out without solvents or in highly concentrated monomer solutions, without the heat of reaction leading to undesirably severe overheating of the mixture, even with intensive cooling and stirring comes. Therefore one works in solutions with lower concentrations and thus with considerable Solvent volumes that are recycled for cleaning purposes. The necessary low polymerization temperature and the purification of the co-solvents increases the cost of the facilities and increases the cost of the Manufacturing process of polyisobutylene rubbers.

The invention relates to a process for the polymerization or for the copolymerization of olefinic monomers which are polymerizable by a cationic mechanism, especially of isobutylene per se or with dienes Exposure to light on the reaction mixture, which is used as catalysts, halides of tetravalent titanium, vanadium or Contains zirconium. This process enables the high molecular weight polymerization of isobutylene under a lot to carry out more advantageous conditions than is the case with the previously known technological processes is. It enables the polymerisation to a high molecular weight at a controllable rate without solvents Polymer can also be carried out at a relatively high temperature.

So far it was only known that the polymerization of monomers, which can be polymerized by free radicals,

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accelerated by irradiation in the presence of peroxidic or azo initiators or photosensitizers such as benzoin. In the case of monomers which, such as, for example, isobiitylene, cannot be polymerized with the aid of free radicals, however, no polymerization catalyst has hitherto been known which could be activated by irradiation or exposure. It has now been found that with isobutylene and unsaturated monomers which can be polymerized according to a cationic mechanism, the polymerization can be caused or accelerated by exposure to light even in a well-dried environment without the addition of cocatalysts, if halides of tetravalent titanium, yanadine or zirconium are used as catalysts . It was found here that the polymerization catalized with vanadium / rvy chloride proceeds only very slowly in the dark, but is considerably accelerated by daylight or by lighting with an electric incandescent lamp, possibly with a mercury lamp or an infrared heater. In contrast, a polymerization catalyzed with titanium halides only started after irradiation with an incandescent lamp and its speed increased in the order TiOl ₄ <TiBr ^ (TiJ ₄ . when using halides of titanium, vanadium and zirconium as catalysts - their acceleration. The overall rate of polymerization depends on the concentration of the catalyst and on the intensity of the light used (ultraviolet, visible, infrared). By metering the catalyst and by Regulation of the light intensity or by alternately switching the light source on and off, the speed can be regulated in such a way that the polymerization takes place even with less intensive cooling and conversion.

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stirring only in a narrow temperature range, practical isothermal, runs. This process thus enables polymerisation without a solvent under isothermal conditions perform. Compliance with almost isothermal conditions contributes to the production of polymers with a narrow polydispersity of the molecular weights. When polymerizing without a solvent, separation occurs of the polymer from the monomer solution, if the molecular mass of the resulting polymer is sufficiently large. That Reaction mixture has a pulpy consistency, so it can even be around $ 30 with relatively high sales Stir well and cool for the solution poly ™ Aliphatic, aromatic or chlorinated hydrocarbons can be used as solvents.

It was found that the copolymerization of isobutylene with. Dienes in a well-dried environment and in an inert atmosphere without the addition of cocatalysts by exposure to light on the reaction mixture in the presence caused and accelerated by halides of tetravalent titanium, vanadium or zirconium can. To induce and accelerate the copoly- merization, irradiation with a mercury can be used lamp, an electric light bulb or an infrared heater. Since the reactions after Turning off the light can stop the polymerization rate due to the intensity of the Light source and / or can be regulated by alternately switching the lighting on and off. Because the speed the polymerization also depends on the concentration of the catalyst, it can therefore also be metered of the metal halides can be regulated with simultaneous irradiation of the reaction mixture. By regulating the The rate of polymerization can remove the heat of reaction from the mixture even at less intense

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Cooling and stirring are ensured in such a way that there is no overheating and the reaction is practically isothermal. The copolymerizations can thus also be carried out isothermally in the absence of an auxiliary solvent. When a copolymer with a sufficiently high molecular weight is formed, the polymer is deposited from the monomer mixture. The pasty mass can still be mixed and cooled well at conversions around 30 ° β>. The molecular masses of the copolymer, especially that of isobutylene with butadiene, are significantly higher than in the case of a copolymerization which occurs under comparable conditions in processes customary in industry. These differences are striking especially when copolymers, prepared at higher temperatures, so that copolymers with the usual commercial butyl rubbers I.iolekülmassen of the subject invention can be obtained even at temperatures of -20 to ⁰ -4o according G. The unsaturation of the copolymers varies $ e on the composition of the starting mixture j at a relatively high unsaturation (around $ 3) and sufficiently high molecular weights, the copolymers in the reciprocal number of cases in organic solvents are well solvable. In addition to butadiene and isoprene, the copolymerization of isobutylene can also be carried out with advantage with 2,3-dimethylbutadiene-1,3, piperylene, cyclohexadiene, cyclopentadiene, alkoxybutadiene, chloroprene and with dimethallyl. For solution polymerization, aliphatic, aromatic and chlorinated hydrocarbons can be used as solvents.

Example 1t

A block polymerization of isobutylene was carried out, in an all-glass reactor under strictly dry conditions in an argon atmosphere

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and with constant stirring of the reaction mixture with a magnetic stirrer. The reactor was filled with 25 ml of isobutylene ( ^{degree of purity 99 »2 l} ß>) , which after! Tempering to -4-0 ⁰ G 1. 10 "^ moles of litanthene tetrachloride dissolved in n-heptane was added. The polymerization began after. Irradiation of the reactor with a mercury lamp (250 watts), which is noticeable by the increase in the temperature and the viscosity of the reaction mixture the conversion achieved in the polymer products was 30 #;; observed Gkrenzen between -40 to -58 ⁰ G, the irradiation of the reactor was ever interrupted as required after one hour, the reaction was terminated by addition of alcohol. whose molecular weight determined by means of viscometric method, showed the value of 130,000.

Example 2:

The polymerization of isobutylene without a solvent was carried out as described in Example 1, with the difference that titanium tetraiodide was used as the catalyst instead of the chloride. By briefly irradiating the reactor with a mercury lamp, rapid polymerization was started, which is accompanied by the precipitation of the polymer formed from the lonomer solution, the polymerization reaction slowly subsiding. To further stimulate the polymerisation it is sufficient to use ordinary electric light (100 watt incandescent lamp); by alternately bond and off the light source, it is possible to keep the reaction according to need in such a screw so that the temperature remains adhered to the Reaktionsgemisehes in the range -40 to -38 ⁰ G. With a conversion of 45 ° ß> achieved after 30 minutes, the KoIe-

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Bulk weight of the polymer 4-50,000. The molecular weight of a polymer prepared at -78 ° C was 2. 10 ⁶ .

Example 3:

The polymerization of Iaobutylene without solvent was carried out - as described in Example 1 -, but with the addition of 1.2. 10 moles of vanadium / IV / chloride as a catalyst and when irradiated with an electric incandescent lamp (200 watts). The polymerization proceeded in the course of one hour to a conversion of 45 #, with simultaneous deposition of the polymer from the monomer solution. The molecular weight of the prepared -4o at ⁰ C the polymer was 250,000.

Example 4;

At a temperature of -50 ⁰ G, the polymerization of a 30 #igen (WW) of styrene solution in n-heptane was conducted with vanadium / IV / chloride as catalyst, and when irradiated with room light (200 watt bulb). The reaction took place in a goose glass reactor and was accompanied by the deposition of the polystyrene as a fine powder from the heptane solution. The catalyst was added successively in small doses in the form of its 0.5 molar solution in n-heptane; its total consumption was 2. 10 mol / 100 g of a 30 # strength monomer solution. The polymerization proceeded in the course of an hour to a conversion of £ 85.

Example 5 »

The polymerization of the Isobutylvinylathers was stirred at -30 ⁰ C with a 30 ^ by weight (W / W) monomer solution in n-heptane

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—4 carried out. To 25 g of this solution was 0.1. 10 moles of titanium tetraiodide were added and the mixture was irradiated with a mercury lamp. The polymer precipitates out of the solution in the course of the polymerization. After 1 hour, a 100 consecutive conversion into polymer products was achieved; their intrinsic viscosity was 0.95.

Example 6i

The polymerization of the isobutylene was carried out at a temperature of -3O ⁰ O with a 30% strength (W / W) monomer solution in methylene chloride. For 40 g of this isobutyl

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oil solution was 0.2. 10 moles of titanium tetrabromide were added and the mixture was irradiated with a mercury lamp for 1 hour. The polymerization proceeded up to a conversion of 90 % with separation of the resulting polymer from the solution. The molecular weight of the resulting polyisobutylene was 150,000.

Example 7:

The polymerization of isobutylene was carried out with its 30> Sigen (W / W) solution in toluene at a temperature of -10 G and under irradiation with a mercury lamp (250 watt). To 30 g of this solution was 0.1. 10 "" * moles of titanium tetraiodide were added, the irradiation was maintained for 45 minutes. The polymerization proceeded practically completely through (conversion 100 io) \ the molecular mass of the polymer obtained was 110,000 ..

At a temperature of -4O ⁰ C, the Kopolymeriua

Example 8 ":

At a T

tion of isobutylene with styrene without auxiliary sweet

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carried out, with vanadium / IV / '- chloride as a catalyst and when initiated by irradiation with an electric incandescent lamp (200 watts). The mixture used contained 25 g Isobutylene and 5 g of styrene, to which 1.5. 10 moles of yanadine / IV / chloride was added. That in the course of the polymerization The copolymer that forms gradually precipitates out of the lonomer mixture. The polymerization is after 1.5 otunden ended; 12 g of a copolymer are obtained a viscometrically determined molecular weight of 75,000.

example

At a temperature of -4-O ⁰ C, the copolymerization of isobutylene with isobutyl vinyl ether was without liilfslösungsmittel, uecksilberlampe with iitantetrajodid as a catalyst and initiation by irradiation with a ^ carried out. Into the monomer mixture of 25 g of isobutylene

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and 5 g of isobutyl vinyl ether became 0.1. 10 moles of the catalyst added. After the polymerization had proceeded for one hour, it was ended. You win overall 10 g of a copolymer with a molecular weight of 134 x. 000.

Example 10;

A copolymerization of 30 g of a heptane solution was carried out which contained 5 g of alpha-methylstyrene and 5 g of isobutyl vinyl ether. At a temperature of -4-0 ⁰ C was 0.1 as a catalyst. 10 " ³ mol of titanium tetraiodide are added and irradiation with a mercury lamp (250 V / att) is carried out. The copolymer precipitates out of the solution in the course of the polymerization Limiting viscosity number / W = 0.65.

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Example 11:

A copolymerization of isobutylene with butadiene was carried out in an all-glass reactor under strictly dry conditions in an argon atmosphere purified of oxygen and with constant stirring of the reaction mixture with a magnetic stirrer. The reactor was filled with 25 g of isobutylene ( degree of purity 99 »2%) and with 8 g of butadiene. After the temperature has been adjusted to -4O ⁰ G, 1 is added. 10 "^ moles of titanium tetrachloride in the form of its n-heptane solution. The polymerization only began after the reactor had been irradiated with a mercury lamp (250 watts), which was noticeable by the rise in temperature and the separation of the polymer from the monomer solution. Around the temperature The irradiation was interrupted as required at a bath temperature of -45 ° C. After one hour, the polymerization is terminated, and 12 g of a product, which is 10 % of an insoluble gel, are obtained The molecular weight of the soluble fraction, determined with the aid of the viscometric method, is 350,000, its unsaturation 1.8 ^.

Example 12;

The isobutylene was copolymerized as described in Example 2, with the difference that 1 g of isoprene was used instead of the butadiene. The resulting copolymer contained 15 'ß> gel, calculated on isobutylene at a conversion of $ 50. The molecular weight of the soluble fraction was 330,000 and its unsaturation was then $ 1.5.

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Example 13:

lia was the copolymerization of isobutylene with butadiene carried out under the same conditions as described in Example 1, with sitanetetraiodide as the catalyst. The resulting copolymer has a molecular weight at a conversion of 45%, calculated on the isobutylene from 280,000 to.

Example 14 ·;

At a temperature of -40 0, a copolymerization of isobutylene with butadiene was carried out in an all-glass reactor, without auxiliary solvents, with constant stirring with a magnetic stirrer and using vanadium / IV / chloride as a catalyst. The butadiene used had a degree of purity of 99 »2 - /> » the catalyst was metered in in the form of its 0.3 molar solution in n-heptane. Initially 180 g of isobutylene and 58Ag of butadiene were condensed into the dried-out reactor under inert gas. After additions of 1.1. The reaction mixture was irradiated with the light of two incandescent lamps (200 watts) for 10 mol of titanium tetrachloride, and after 1.5 hours the reaction was inhibited at a conversion of 32 fo. A product is obtained which is completely soluble in organic solvents and whose molecular weight, determined by the viscometric method, has a value of 400,000 and its unsaturation is 2.2 fo. The copolymer obtained can be well vulcanized with the usual vulcanizing agents used in the vulcanization of butyl rubber.

Example 15:

In an all-glass reactor with a magnetic stirrer

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- described in Example 14 - the copolymerization of isobutylene with isoprene was carried out without auxiliary solvents, a 0.3 molar yanadine / IV / chloride solution in n-heptane being used as the catalyst. 25 g of isobutylene and 0.5 g of isoprene are condensed into the reactor under inert gas. After adding 1.6. 10 mol of VCl ^ the reaction mixture was irradiated at -4O ⁰ G for one hour with the light of a 200 watt G incandescent lamp; the reaction is inhibited after a conversion of $ 4-0 has been achieved. A copolymer is obtained whose molecular weight, determined by the viscometric method, has a value of 250,000 and its unsaturation is 1.1 fo.

Example 16;

A copolymerization of the isobutylene was carried out as described in Example 1, piperylene being used in an amount of 5 g instead of the butadiene. With a conversion of $ 40> t, calculated on the isobutylene, the resulting copolymer has a molecular mass of 360,000.

Example 17:

At a temperature of -40 ⁰ O the copolymerization of isobutylene with butadiene was carried out in a n-hexane solution, with titanium tetra;} ο did as catalyst and "upon initiation by irradiation with a mercury lamp. The reactor was filled with 30 g of a solution, which contained 10 g of isobutylene and 3 g of butadiene, after which

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2. 10 moles of catalyst was added. After two hours, the polymerization was ended and the conversion achieved, calculated on the isobutylene content, was 80 fo. The molecular weight of the copolymer was 230,000.

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Example 18:

At a temperature of -4-0 C the copolymerization carried out a 30 g batch of a monomer solution in carbon tetrachloride containing 10 g of isobutylene and 3 g With an addition of 2.10 mol of vanadium / rV "/ chloride, butadiene contained as a catalyst. The polymerization took place in an inert gas atmosphere when the reactor was irradiated with an electric incandescent lamp (200 ./a't'fc) for a total of 2 hours. Sales in Polymer products, calculated in relation to the isobutylene used, was 85% the molecular weight of the Copolymers was 180,000.

example

At a temperature of -30 ⁰ C was added in an inert gas atmosphere and in the presence of vanadium / IV / chloride, the copolymerization of butadiene with styrene performed. The reactor was filled with 20 g of butadiene and 10 g of styrene; after adding 1.2. The reaction mixture was irradiated with an electric incandescent lamp (200 watts) for 10 moles of the catalyst for 2 hours. When the polymerization was complete, 5 g of a copolymer which is insoluble in the usual solvents are obtained.

Example 20:

At a temperature of -5O ⁰ O, a copolymerization of isobutylene with isoprene in a toluene solution, catalyzed with titanium tetrabromide, was carried out in a protective gas atmosphere. The reactor was filled with 50 g of a 1.ionomer solution in toluene, the 15 g of isobutylene

—4 and 0.5 g of isoprene, after adding 2.10 mol i'itantetrabromid was the reaction by irradiation

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started with a mercury lamp. After the end of the polymerization - after 2 hours - a total of 14 g of a copolymer with a molecular weight of 31,000 and an unsaturation of 1.6% is obtained .

Example 21:

At -78 ⁰ G copolymerization of a vinyl ether with isoprene with i'itantetrajodid performed · to 50 was in an n-heptane g of a solution containing 15 g of isobutyl vinyl ether and 0.5 g of isoprene was. 2 10 mol of the catalyst were added and the reaction mixture was irradiated with a mercury lamp. After one hour of polymerization, 12 g of a copolymer with a maximum viscosity number of 1.82 are obtained.

Example 22:

At a temperature of -30 ⁰ C was in the presence of 1.2. 10 moles of vanadium / IV / chloride and under irradiation with an electric incandescent lamp (200 watts) carried out a copolymerization of a mixture which contained 25 g of isobutylene and 3 g of cyclopentadiene. The copolymer that forms separates out of the monomer solution in the course of the polymerization. At an isobutylene-based conversion of 45? », Which was achieved after one hour, the molecular weight of the copolymer was 550,000.

Example 23:

At a polymerization ^{temperature of -20 0} C was with catalysis with an addition of 1.2. 10 "^ moles of vanadium / IV / chloride and accelerated by irradiation with an electric incandescent lamp (200 watts) the copolymer!

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sation carried out oines monomer mixture, which contained 25 g of isobutylene and 3 g of 2,3-dimethylbutadiene-1,3. After the end of the polymerization after one hour, 11 g of a copolymer with a molecular weight of 150,000 and an unsaturation of 1.1 % are obtained.

Example 24;

At a temperature of -40 ° 0 in the presence of vanadium / IV / '- chloride and under irradiation with an electric Incandescent lamp (200 watts) a copolymerization of isobutylene with isoprene in a methylene chloride solution carried out. 50 g of this solution were used, the 20 g of isobutylene, 1 g of isoprene and 1.5. 10 "moles of vanadium / IV / chloride contained. When the polymerization has ended - after 4-5 minutes - 18 g of a copolymer are obtained with a molecular mass of 230,000.

Example 25 1

One was initiated with vanadium / IV / bromide and light Polymerization of isobutylene carried out without auxiliary solvents. To 25 g of a cooled to -40 ° 0 and The light-protected monomer became 5.10 moles of vanadium / IV / bromide added in the form of its toluene solution. In the dark there is practically no polymerization, which only occurs when the mixture is irradiated an electric incandescent lamp (200 watts). After 30 minutes the polymerization was complete Addition of ethyl alcohol ended; 10 g of a polymer with a molecular weight of 230,000 are obtained. It was similar also the polymerization catalyzed by vanadium / IV / iodide. Under the same conditions as when using vanadium / IV / bromide, one gains after 30 minutes continuous polymerization 8 g of a polymer with a molecular weight of 210,000.

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Example 26s

the copolymerization of isobutylene with chloroprene carried out at -78 C without auxiliary solvents.

The Llonomergeiaisch contained 22 g isobutylene and 4.4 g

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Chloroprene. The catalyst was 1.8. 10 KoI vanadium tetrachloride used. After the catalyst had been metered in, the reaction mixture was illuminated for 5 seconds with a 500 watt incandescent lamp and after 30 minutes the reaction was terminated at a conversion of 42 $ and a viscosity average molecular weight of 300,000 with the addition of ethanol. The resulting copolymer was soluble in common organic solvents, and contained 2.48 f »chlorine and 1.7 ^ double bonds.

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Claims (1)

PATENT CLAIM {J}. Process for the polymerization and for the copolymerization of cationically polymerizable monoolefinic ionomers, in particular of isobutylene per se or with dienes, characterized in that the polymerization or the copolymerization is effected by the action of ultraviolet, visible or infrared light on the halide of tetravalent titanium, vanadium or zirconium-containing reaction mixture is caused and / or accelerated. 2 · The method according to claim 1, characterized in that the polymerization rate by metering the catalyst and by the intensity of the irradiation or as required Switching the light source on and off is controlled. 3. The method according to claim 1 and 2, characterized in that the polymerization without solvents or in solution in aliphatic, aromatic or halogenated hydrocarbons is carried out. 4-. Process according to Claims 1, 2 and 3, characterized in that the polymerization is carried out in the temperature range from +30 to -14-0 0. 109849/1626