DE1157784B - Process for the catalytic polymerization of unsaturated esters - Google Patents

Description

The invention relates to the polymerization of vinyl esters or acrylic acid esters, in particular of esters of «-Alkylacrylsäuren, where in the following "Alkyl" also means "cycloalkyl" compounds.

A process for the catalytic polymerization of vinyl esters or acrylic acid esters, in particular esters of the A-alkyl acrylic acids alone or found in a mixture with one another, in which the catalyst used consists of a trialkylaluminum or a dialkyl aluminum chloride with 1 to 8 carbon atoms per alkyl group and an alcohol which is either an alkenol with one more than 2 carbon atoms removed from the hydroxyl group. Multiple bond or an alkanol of the general formula

in which η is a number from 1 to 24, χ 1, 2 or 3 and m has the meaning of 2 η + 2 - χ . When reference is made in the following to an alcohol catalyst component, an alcohol of these classes is meant.

Eligible applications esters of acrylic acids include the following: ethylene glycol - dimethacrylic, polyethylene glycol - ^ methacrylic acid ester, methacrylic acid methyl ester, "-Äthylacrylsäuremethylester," -Propylacrylsäureäthylester, propylene-a-äthylacrylsäureester, "-Phenylacrylsäureäthylester, χ - Chloracrylsäuremethylester," - Cyclohexylacrylsäureäthylester and "-Decylacrylsäuremethylester.

The use of aluminum alkyls as components of the so-called "Ziegler catalysts" for the polymerization of olefin monomers is well known. However, the effectiveness of aluminum alkyls is and an alcohol as a catalyst for polymerizing the above-mentioned esters therefore as surprising to look at because oxygen-containing impurities, such as moisture and carbon dioxide, in the polymerization of ethylene and propylene, as is well known, regarded as poisons for the aluminum alkyls will. In addition, it is noteworthy that a by the addition of an alcohol to an aluminum alkyl compound formed catalyst, the monomers used in the process according to the invention (e.g. vinyl acetate) polymerized because the polymerization of monomers, such as vinyl acetate, does not use With the help of the “Ziegler catalysts” could be achieved (cf. Gaylord and Mark, “Linear and Stereoregular Addition Polymers ", p. 298, Interscience Publishers, 1959). It continues to be even more surprising consider that the alcohol in the poly process for catalytic polymerization unsaturated ester

Applicant:

W. R. Grace & Co.,

New York, N.Y. (V. St. A.)

Representative:

Dipl.-Chem. Dr. rer. nat. JD Frhr. v. Uexkull,
Patent attorney, Hamburg-Hochkamp, Königgrätzstr. 8th

Claimed priority:
V. St. v. America of February 8, 1960 (No. 7106)

Aristotle George Prapas, Haddonfield, N. J.

(V. St. A.),
has been named as the inventor

merization of the esters mentioned not only has no poisoning effect on the aluminum alkyl compound but that it instead shows a synergistic effect which leads to an increased polymer yield which, as will be shown, is even larger than when using one alone Aluminum alkyl existing catalyst; alcohol alone has no catalytic effect. The reason for this synergistic effect of the catalyst components is not known. the Experiments show that the catalyst components are preferably mixed in the presence of the monomers should be. Premixing the catalyst before adding it to the monomers to be polymerized leads to low yields; however, these yields are still better than what they are can be achieved with the sole use of aluminum alkyl compound as a catalyst. Farther the results show that the catalyst components are preferably the monomers at low Temperatures are to be added so that optimum polymer yields are achieved. At any given The polymerization reaction temperature gives an initially lower temperature for the process step the addition of catalyst greater polymer yields than when the catalyst is added and the polymerization reaction is carried out at the same temperature. The addition of the catalyst is preferably carried out at a temperature below

309 749/443

3 4

-20 ° C, with the lower limit of the miniums (TIBA) (5.6 millimoles) in heptane by the The freezing point of the solution to be polymerized. Metal lid and the pierceable rubber washer The temperature of the polymerization was charged at normal pressure. The jar was immediate is for any given pressure through the compo- on it in a dry ice bath (-24 ° C) in a light center limited, which brought the lowest boiling point 5 tight shaker in which it owns. Of course, higher temperatures can be shaken mechanically for 5/2 hours. Dates can be used when the dry ice bath has been depressurized from the container instead of normal after is worked under overpressure. The polymer is removed, which then takes another 16 hours at a sation is generally shaken mechanically at temperatures of 22 ° C. Range from -25 to 40 ° C or higher below normal 10 The container was then opened and the bottle pressure was checked carried out. The preferred method is worked out as follows:

it says that at the lower temperature limit the contents were dissolved in 50 ml of methanol and

is started, and that the mixture is poured up to / _o poured into 250 ml of 5 ° aqueous hydrochloric acid solution.

Let it warm up to room temperature or higher. The polyvinyl acetate precipitated in this way was

Take the molar ratio of the catalyst components 15 and add 100 ml in a Waring mixer

is not essential. Crush a suitable molar ratio of water. The product was then over

Aluminum alkyl compound to alcohol lies in one night at 45 ° C and a pressure of 30 mm Hg

Range from 5: 1 to 1:10, however a ratio is dried. The dried polymer weighed 7.8 g,

of about 1: 1 or between 1: 1 and 1: 1.2 preferred. _{which corresponds} to a 90.7 ° / ₀ by weight conversion of the distilled

Examples of aluminum alkyls to be used are equivalent to vinyl acetate 20. The polyvinyl acetate had

Trimethyl, triethyl, tripropyl, triisopropyl, tri-one measured at 25 ° C in methyl ethyl ketone (MEK)

butyl, triamyl, triisoamyl, trihexyl, triisohexyl, intrinsic viscosity of 0.7.

Triheptyl and trioctyl aluminum, as well as the The following example shows with a lower

corresponding dialkyl aluminum chlorides. Conversion the feasibility of the present

The catalytic alkenols, which as alcohol 25 invention in the absence of a solvent.

Catalyst component can be used.

are oleyl alcohol, ω-undecylenyl alcohol, 4-hexene Example 11

1-qI, l-pentan-5-ol, 4-octen-l-ol, 3-buten-l-ol. The implementation was carried out analogously to Example I

Alkanols can lead to methanol, ethanol, 1-propanol, but now no n-heptane is added and that

2-propanol, 1-butanol, isobutyl alcohol, 2-butanol, 30 mixture 4V ₂ hours at -23 ° C mechanically

tert-butyl alcohol, amyl alcohol, isoamyl alcohol, and then shaken at room temperature

tert-amyl alcohol, sea-amyl alcohol, n-hexyl alcohol, temperature (20 ° C) was shaken for 76 hours.

n-heptyl alcohol, n-octyl alcohol, n-nonyl alcohol, It must be noted that the 76 hours of shaking

n-decyl alcohol, n-undecyl alcohol, lauryl alcohol and at room temperature was not necessary but

Myristyl alcohol can be used. 35 done for convenience only

Polymerization is preferred, but has not been. Within the preferred temperature range, it is essential to carry out the polymerization step in the presence of a solvent. The solvent used should be inert, a shaking time of 8 hours and not with the monomers to be polymerized, or less, in order to react with the maximum achievable polymer wall polymer chain under the prevailing catalysts used or the growing conditions. To be achieved as an inert solvent. After working up the product, dry aliphatic hydrocarbon solutions are used, as in Example I, the weight of the dried agent of the alkane and cycloalkane groups was preferred. Polyvinyl acetate 5.14 g, which corresponded to a 59.8 ⁰ ZoISeO Um-Suitable examples for such preferred solution conversion. The means measured according to Example I are n-pentane, η-hexane, n-heptane, n-octane, 45 intrinsic viscosity of the polymer was 0.7.
n-nonane and cyclohexane. However, it can also
aromatic hydrocarbons, ζ. B. Benzene, Toluene Example 111
or chlorobenzene can be used. Analogously to Example I, a mixture of 14.0 ml

In the following, the invention is based on some n-heptane, 9.3 ml (0.1 mol) of vinyl acetate, 0.24 ml of Me-

Examples are explained in more detail. All numbers that contain 50 ethanol and 2.0 ml of a solution of triisobutyl

The conversion concerns relate to the aluminum (6.0 millimoles) made in heptane. That

Weight of monomer starting material. this mixture containing vessel was in the

Shaking container with dry ice brought and 5Va hours

Vinyl acetate polymerization takes place mechanically at a temperature of -30 ° C

Example I ⁵⁵ shaken. The reaction was interrupted at -30 ° C and the contents poured into a 5% aqueous salt

Poured into a 3 50 ml poly acid solution filled with dry nitrogen. The dried polymerisation vessel made of Pyrex glass was 10 ml of dry vinyl acetate weighed after work-up according to Bein heptane, 9.3 ml (0.1 mol) of distilled vinyl acetate game I 1.88 g and had in methyl ethyl ketone at 25 ° C and 0.20 given ml of methanol. The jar had an intrinsic viscosity of 0.49 at 60. The total area of a puncturable neoprene rubber and converter washer was 21.8 "from closed with a metal lid; this metal.
lid had a sufficiently large opening in the middle Example IV
for the introduction of a hypodermic syringe. After the same mixture was closed as in Example III, the vessel was cooled to -60 ° C, prepared at room temperature (22 ° C) and then placed in the shaking container with a syringe whose needle was long enough 5 ³ Z ₂ hours at and down to the bottom of the vessel, 2.0 ml of a room temperature (22 ° C) mechanically shaken solution of a commercially pure triisobutylalu was. According to the structure described in Example I

processing were (/ _O by weight conversion 15.3 °) trockn.es Vinylacetatpolymerisat obtain 1.31 g with a viscosity of 0.25. A comparison of the yields of Examples III and IV with that of Example I clearly shows that adding the catalyst at lower temperatures and then carrying out the polymerization at a higher temperature is more advantageous compared with carrying out the addition of the catalyst and polymerization at the same temperature. . . ,

Example V

The procedure was analogous to Example I, except that 3.4 ml of a solution of triethylaluminum (TEA) (6.1 millimoles) of commercial purity dissolved in heptane were used instead of the triisobutylaluminum solution. The experiment was interrupted after mechanical shaking for 5 to ₂ hours at -25 ° C. After work-up, 4.57 g (53.2% conversion) of dry polymeric vinyl acetate was obtained.

Example VI

The procedure was analogous to the previous example, but now, after _{mechanical shaking at -25 ° C for 2} hours, the addition of dry ice was interrupted and the shaking was continued for a further 16 hours while the contents warmed to 16 ° C. There was obtained 7.07 g of dry polymeric vinyl acetate corresponding to an 82.4% conversion.

A comparison of Example V with Example IV shows the ability of the system to continue the polymerization, when the temperature of the polymerization step is increased by a small amount. Since the rate of polymerization decreases rapidly with time at any given temperature, a continuously increasing temperature is preferably preferred in order to achieve the greatest possible conversion of the monomer occurs at any given time.

Example VII

The reaction was carried out as in Example III, but now 0.72 ml of methanol was added instead of 0.24 ml. After _{mechanical shaking for 2} hours at -30.degree. C., the product was worked up analogously to Example I. The dry polymer had a weight of 0.93 g and had a viscosity of 0.3 in methyl ethyl ketone at 25 ° C. The conversion was 10.8%.

Comparative experiment A

The procedure and the ingredients according to Example III were used, but now no triisobutylaluminum was added as a catalyst. After an hour and a half mechanical Shaking at -30 ° C. gave no polymer.

Comparative experiment B

The same procedure and with the same reactants as in Example III were used, but now no methanol was added. After mechanical shaking for 5 to ₂ hours at -30.degree. C., the polymer produced was worked up according to Example I. The yield of dry

The polyvinyl acetate was 0.23 g, which is 2.7% strength Conversion corresponds to.

A comparison of Examples III with Comparative Experiments A or B shows the synergistic effect of the catalyst components when these are used together, compared with when these substances are used alone. While the alcohol alone cannot catalyze a polymerization reaction (comparative experiment A), when used together with the aluminum alkyl (example III), a conversion that is eight times as great as when aluminum alkyl was used alone (comparative experiment B) is achieved. _. . , _ΤΛΤΤΤ,. ._, "' Example VIII to XV

The following table shows the use of various alcohols as a catalyst component.

Table I.

n-heptane, ml

Vinyl acetate, ml

TIBA in heptane (5.6 millimoles, ml)
Type of alcohol

Amount of alcohol, ml

Temperature on addition of the catalyst, ⁰ C

Polymerization temperature ^{, 0 C 1} )
Polymerization temperature ^{, 0 C 2} )

Dry polymer, g

Conversion,%

Intrinsic viscosity
(MEK at 25 ° C)

VIII

IX

XI

example
I XII

XIII

XIV

XV

10
9.3
2.0

Methyl alcohol

0.20

-60
-24

22nd

7.8
90.7

0.7

10
9.3
2.0

tert-

Butyl

alcohol

0.47 -60

Yes

22nd
5.92

1.2

10 9.3 2.0

tertiary amyl alcohol

0.54

-60

-24

22nd

6.13

71.3

0.9 10
9.3
2.0

2-octanol

0.79

-60

-24
22nd
6.49

75.5

1.5

10
9.3
2.0

1-octadecanol

1.35g

-60

-24
22nd
3.35

38.9

0.7

10
9.3
2.0

1.3-

Propanediol

0.36

-60

-24

4.80

55.9

0.7

9.3

2.0

Isopropyl alcohol

0.38

-60

-23 20 4.77

55.5

1.1

9.3

2.0

Isoamyl alcohol

0.54

-60

-23 20 7.47

86.9

1.1

^J ) Examples VIII to XIII Residence time at the specified temperature:

specified temperature: 4V2 hours.
*) Examples VIII to XIII Residence time at the stated temperature: stated temperature: 76 hours. 5V ₂ hours, Examples XIV and XV residence time at the 16V2 hours, Examples XIV and XV residence time at the

Example XVI

12 ml of chlorobenzene, 4.7 ml (0.05 mol) of distilled vinyl acetate and 0.24 ml of methanol were in a 350 ml "Pyrex" polymerisation vessel, which was previously cleaned at a temperature of -60 ° C with a dry Nitrogen had been filled. The jar came with a puncturable neoprene rubber pad and a metal lid closed with a hole through which, analogously to Example I, using a syringe 2 ml of a commercial grade solution of triisobutyl aluminum (5.6 millimoles) in heptane were introduced. The jar was placed in a light-tight shaking container, which by means of Dry ice was kept at a temperature of -23 ° C and mechanically shaken for 5 hours. Then the addition of dry ice was stopped and the jar shaken for a further 18 hours it warmed to room temperature (22 ° C). After this period of shaking, the polymer became recovered by pouring the clear solution prepared therefrom into 200 ml of heptane for precipitation. The precipitate was taken up and dissolved in 100 ml of methanol, which contained 10 ml of concentrated hydrochloric acid, dissolved. The resulting solution was then poured into 300 ml of water to precipitate the polymer. The polymer was comminuted in a Waring mixer and kept at 45 ° C. and overnight 75 mm Hg dried. The dried polymer weighed 0.63 g, which corresponds to a 14.3% conversion.

Methyl Methacrylate Polymerization Example XVII

A mixture of 9.45 ml of methyl methacrylate, 0.20 ml of methanol and 2.0 ml of triisobutylaluminum (5.6 millimoles) in heptane was prepared as described in Example I for the preparation of vinyl acetate. The vessel containing the mixture was placed in a light-tight shaking container in a dry ice bath (−23 ° C.) and mechanically shaken ^{4 ×} / _{2 hours.} The mixture was then poured into 300 ml of methanol, which contained 35 ml of concentrated hydrochloric acid, to precipitate the polymer. The polymer was collected and dried at 5O ⁰ C and 30mm Heg pressure. The dried methyl methacrylate polymer weighed 2.71 g and had an ^{intrinsic viscosity, measured in methyl ethyl ketone at 25 °} C., of 0.75. The conversion was 30.7%.

Example XVIII

According to the procedure of Example XVII A mixture of 10 ml of methyl methacrylate, 20 ml of n-heptane, 0.24 ml methanol and 4.0 ml of a solution of triisobutylaluminum (12 millimoles) in heptane was prepared and at a temperature of ⁰ C -6O placed in a 350 ml "Pyrex" polymerization jar. The vessel was mechanically shaken in a light-proof shaking vessel for 6 hours at -40 ⁰ C and then for 64 hours at + 17 °. The work-up of the product, carried out according to the procedure of Example XVII, gave 4.41 g of dry methyl methacrylate polymer, which corresponded to a conversion of 47.1%.

Example XIX to XXI ^6s

The following table shows the use of various alcohols as catalyst components.

Table II XIX example
XX XXI 9.45 9.45 9.45 5 Methyl methacrylate, ml 2.0 2.0 2.0 5.6 millimoles of TIBA
in heptane, ml Methyl- Iso-
propyl Iso-
amyl IO Type of alcohol 0.20 0.38 0.54 Amount of alcohol, ml -60 -60 -60 15th Temperature at addition
of the catalyst, ⁰ C -23 -23 -23 Polymerization
temperature 2.71 2.03 2.19 Dry polymer,
B ¹ ) 30.7 23.0 24.8 20th Conversion,% 0.75 0.53 0.53 Intrinsic viscosity
(MEK at 25 ° C) ...

*) Dwell time at the temperature 4Va hours.

Ethylene glycol dimethacrylate polymerization, comparative experiment C A mixture of 9.3 ml of ethylene glycol dimethacrylate, 14.7 ml of n-heptane and 1.0 ml of a solution of triisobutylaluminum (2.8 millimoles) in heptane was placed in a 350 ml "Pyrex" polymerization vessel which was filled with dry nitrogen at -60 ° C. The vessel was placed in a dry ice bath (-40 ⁰ C) in a light-tight container, and vibrating mechanically shaken in this three quarters of an hour. The polymer produced was worked up by dissolving the contents of the polymerization vessel in 100 ml of methanol and pouring the solution into 500 ml of a 5% strength aqueous hydrochloric acid. The polymeric product was then washed with methanol and dried overnight at room temperature and a pressure of 50 mm Hg

dried. The dried ethylene glycol dimethacrylate polymer weighed 2.66 g, which is a conversion of 26.9%.

The effect of adding alcohol is illustrated by the next example.

Example XXII

The same mixture as in Comparative Experiment C which, however, still contained 0.12 ml of methyl alcohol, was shaken mechanically for three quarters of an hour. After working up according to Comparative Experiment C 8.95 g of dry polymer were obtained, which corresponded to a conversion of 90.4%.

Polyethylene glycol dimethacrylate polymerization Example XXIII

A mixture of 23 ml of toluene, 15 ml of polyethylene glycol dimethacrylate, 2.0 ml of a solution of triisobutylaluminum (5.6 millimoles) in heptane and 0.24 ml of methyl alcohol was placed in a 350 ml "Pyrex" polymerization vessel according to Example I, which was filled with nitrogen at a temperature of -6O ^{0 C.} The vessel was placed in a light-tight shaking apparatus and at 2% hours

-40 ° C shaken. After working up according to Example XXIV, 14.5 g of dry polymer, corresponding to a conversion of 89%> obtained.

Example XXIV

In a 350 ml "Pyrex" polymerization vessel filled with dry nitrogen, ΙΟτηΙ were dry n-heptane, 9.3 ml (0.1 mol) of distilled vinyl acetate and 0.21 ml of methanol were added. The jar was with a pierceable neoprene rubber disk and a metal cap provided with a hole closed; the hole in the center of the metal cap was large enough to allow a hypodermic needle to pass through. After closing the jar, it was cooled to -60 ° C, whereupon with a syringe, whose needle was long enough to reach the bottom of the jar, 2.0 ml of a cyclohexane solution of diethylaluminum chloride (5.6 millimoles) of commercial purity through the metal cap and the ao pierceable rubber washer was introduced. The jar was immediately placed in a dry ice-isopropanol bath (-25 ° C) placed in a light-tight shaking container and in this 5Va hours mechanically shaken. Thereafter, the addition of dry ice was stopped and the shaking was stopped continued for a further 12 hours while heating to 27 ° C. The container was then opened and the The contents of the bottle are dissolved in 50 ml of methyl alcohol, whereupon the solution is dissolved in 250 ml of 5% aqueous hydrochloric acid was poured. The precipitate was collected and ground in 100 ml of water in a Waring blender and dried overnight at 45 ° C and 30 mm pressure.

0.881 g of dry polyvinyl acetate corresponding to a 10.2% conversion was obtained.

Example XXV

The procedure of Example XXIV was followed, but now 5.6 millimoles of cyclohexylmethanol,

CH ₂ (CHa) ₄ CHCH ₂ OH

instead of 0.21 ml of methanol and 2.0 ml of a heptane solution of triisobutylaluminum (5.6 millimoles) were used as a catalyst in place of diethylaluminum chloride. There were 0.384 g of dried Polyvinyl acetate obtained, which corresponded to a conversion of 4.5%.

Example XXVI

The procedure was analogous to Example XXIV, but now 5.6 millimoles of oleyl alcohol instead of 0.21 ml of methanol and 2.0 ml of a commercially available heptane solution of triisobutylaluminum (5.6 millimoles) Purity were used in place of diethylaluminum chloride as the catalyst. There were 7.35 g of dried polyvinyl acetate were obtained, corresponding to a conversion of 80.5%.

Example XXVII

10.0 ml of n-hexane, 0.1 mol of methyl methacrylate and 0.21 ml of methanol were placed in a 350 ml "Pyrex" polymerization vessel filled with dry nitrogen. The jar was closed with a puncturable neoprene rubber disk and a metal disk with a hole in the center. The vessel was then cooled to about -60 ° C., whereupon 2.0 ml of a solution of diethylaluminum chloride (5.6 millimoles) in cyclohexane was passed through the metal cap and through the puncturable rubber disk by means of a hypodermic syringe. The vessel was immediately placed in a dry ice-isopropanol bath (-25 ° C.) in a light-tight shaking apparatus, in which it was mechanically shaken for 5 1/2 hours. After this time, the addition of more dry ice was interrupted and the shaking was continued for a further 15 hours, while the temperature gradually rose to 27 ^° C. The container was then opened and the contents of the bottle worked up according to Example XXIV. 0.361 g of dry polymethyl methacrylate corresponding to a conversion of 4.2% were obtained.

It is also possible to use copolymers of the various polymers which can be polymerized by the process according to the invention Esters are obtained when mixtures of two or more monomers are exposed to the action of the catalysts. So let yourself for example vinyl acetate-methyl methacrylate copolymers obtain.

The polymers obtained by the process according to the invention can in the same way as the polymeric products produced by known processes are used. For example are the polymethyl methacrylates for cover panels in tail lights of motor vehicles or used as lenses for signal lighting systems; the polyvinyl acetates serve as an adhesive and as Binder for water-based emulsion paints. The polyacrylates produced by the new process, such as polybutyl acrylate, differ from the previously known products in that they do not even flow at 200 ° C., while the known acrylates have a certain cold flow behavior demonstrate. Accordingly, the articles made from the new acrylate polymers have better dimensional accuracy, especially at higher temperatures.

Claims (1)

PATENT CLAIM: Process for the catalytic polymerization of vinyl esters or esters of acrylic acids alone or in a mixture with one another, characterized in that the catalyst used consists of a trialkylaluminum or a dialkylaluminum chloride with 1 to 8 carbon atoms per alkyl group and an alcohol, which is either an alkenol with one to more as a multiple bond removed from the hydroxyl group by 2 carbon atoms or an alkanol of the general formula in which η is a number from 1 to 2A, x \, 2 or 3 and m has the meaning of 2κ + 2-χ . Considered publications:
German patent specification No. 878 560. Θ 309 749/443 11.63