DE2231995C3 - Process for the preparation of homo- and copolymers of the polyalkenamer class - Google Patents

Description

The invention relates to a process for the preparation of homo- and copolymers of the polyalkenamer class by polymerizing a norbomene, which is an esterified hydroxyl or carboxyl group, a halogen atom or a nitrile group in the 5-position or via an alkylene radical with the Contains 5-position connected, where optionally the 5-position is an alkyl group as a further substituent with 1 to 6 carbon atoms, in the presence of a metallic catalyst system in the liquid phase.

Polyalkenamers belong to a class of polymers which are formed from cyclic olefins by ring opening are generated by polymer molecules between double-bonded carbon atoms, the latter then combine separately with similar carbon atoms of other ring-opened monomer molecules, in order to saturate each other's free valences by creating new double bonds and therefore extended ones Molecular chains are formed.

It is known to use norbornene derivatives using metal catalysts such as ruthenium, iridium and / or to polymerize osmium compounds (GB-PS 12 30 597, J. of Poly. Science A, 895-905 (1965) and Polymer Letters Vol. 3, 1049-52 (1965)). However, these known noble metal catalysts allow just an economically extremely costly process.

The object of the invention is a process for the preparation of homopolymers and copolymers of the polyalkenamer class with high yields, the process being carried out in a simple and economical manner is feasible.

The invention relates to a process for the preparation of homopolymers and copolymers of the polyalkenamer class by polymerizing a norbomene, which is an esterified hydroxyl or carboxyl group, a halogen atom or a nitrile group in the 5-position or via an alkyl radical in the 5-position contains connected, the 5-position optionally being an alkyl group with 1 to 6 as a further substituent May have carbon atoms in the presence of a metallic catalyst system in the liquid phase, characterized in that the catalyst system used is one which is obtained by reacting Halides of tungsten, molybdenum or tantalum with alcohols and organometallic compounds of a metal from group la, Ha, Hb or lila des

Periodic table is obtained.

The ethylene radical is preferably methylene. Suitable tungsten halides are especially WCU, WCU, WOCi ₄ and WO ₂ Cl ₂ - suitable molybdenum halides include molybdenum pentahalide MoCls. Suitable tantalum halides are TaCU and TaBr *. Preferred arganometallic compounds are aluminum alkyls, alkyl hydrides and alkyl halides of the general formula AIR _x X ^ in which χ + y - 3; and .y 1,2 or

ίο is 3; and R is lower alkyl, for example ethyl, isopropyl, isobutyl or n-hexyl; and X (if present) is hydrogen, or preferably halogen, for example chloride. Analogous Mg, Be and Zn compounds can be used as alternatives to the organic aluminum compounds. The proportion of organometallic compound which is incorporated into the catalyst is advantageously greater on a molar basis than the proportion of the W, Mo or Ta halide, for example such that the Al: W atomic ratio is at least 2: 1, preferably at least 4 : 1 and in particular on the order of 10: 1

According to the invention, the catalyst system can optionally be used and / or the polymerization reaction in a suitable organic solvent, for example a cycloaliphatic or aromatic hydrocarbon (such as benzene or toluene) or be carried out. The polymerization reaction is expediently carried out at or in the vicinity of

temperature, but a wide temperature range is permissible. In practice, one will usually choose a temperature in the range from -50 to +50 ", although the temperature is advantageously somewhat higher, for example 55 to 70 ^° C., if products with lower molecular weight are desired. The production of polymers with lower molecular weight is also favored by incorporating into the reaction medium a controlled, small amount of a chain-terminating acyclic monoolefin, e.g.

The esterified hydroxyl or carboxyl group -OCOR or -COOR advantageously has an alkyl radical R with 1 to 6 carbon atoms. According to the invention usable as monomers norbornene compounds are expediently by addition reaction between cyclopentadiene and

so corresponding mono-olefinically unsaturated compounds, for example vinyl compounds, Λ-alkyl vinyl compounds and allyl compounds such as in the British patent. 11 23 878 is described

The following examples illustrate the invention:

example 1

50 g of 5-acetoxy-2-norbornene are diluted with 100 cm ^{3 of} benzene in a flask under a nitrogen blanket. 5 m-mol WoH'ramhexachlorid, dissolved in 100 cm ^J benzene, and 5 m-mol ethanol, dissolved in 50 cm ^J Benzo !, are then added and the contents of the flask are flushed with nitrogen to remove the HCl, which is produced by reaction between WCU and ethanol is released. Then 50m-mol of ethylaluminum sesquichloride (a reaction product

of ethyl chloride with aluminum), dissolved in 50 cm ³

hydrogenated isobutene trimers added. The subsequent polymerization reaction is allowed to proceed for 20 minutes (initial temperature 20 ° C., final temperature 25 ° C.) and the reaction is then terminated by adding 50 cm ^{3 of} a mixture of 1 g of 2,2'-methylene-bis [4, 4'-dimethyl-6,6 '- (l-methylcyclohexyI)] phenol (antioxidant), 3 g of ethanolamine, 20 g of ethanol and 100 cm ^{3 of} benzene are added The yield of polymers! is 38 g (96%) of the molecular weight 68800 ± 1%. The polymer is soluble in benzene, toluene and carbon tetrachloride.

Example 2

30 g of 5-acetoxy-2-norbornene are dissolved in 470 cm ^{3 of} benzene in a flask under a nitrogen blanket. 1 m-mol of tungsten hexachloride is dissolved in 20 cm ^{3 of} benzene and 1 m-mol of ethanol, dissolved in 20 cm ^{3 of} benzene, and 1 m-mol of ethanol, dissolved in 10 cm ^{3 of} benzo], are then added and the contents of the flask are also added Purged with nitrogen to remove HCl released by the reaction between WCk and the ethanol. Thereafter, 2 m-mol of ethyl acetate, dissolved in 2 cm ^{3 of} hydrogenated isobutene trimers, are added. The following polymerisation reaction is allowed to proceed for 120 minutes (initial temperature 20 ° C.) and the reaction is then terminated by adding 10 cm ^{3 of} a mixture of 1 g of 2,2'-methylenebis [4,4'-dimethyl-6,6 '- (Imethylcyclohexyl)] phenol (antioxidant), 3 g of ethanolamine, 20 g of ethanol and 100 cm ^{3 of} benzene. The yield of polymer is 15.2 g (52%). The polymer is soluble in benzene, toluene and carbon tetrachloride.

Example 3

The procedure of Example 1 is followed using 2-norbornene-5-nitrile in place of the 5-acetoxy-2-norbornens repeated. The polymerization reaction time however, in this case it is 120 minutes. The yield of polymer is in the Of the order of 50%. The polymer is common in benzene, toluene, carbon tetrachloride and the others Solvent insoluble.

Example 4

The procedure of Example 2 is followed using the norbornene compound, which by addition reaction between methyl methacrylate and cyclopentadiene, namely des Methyl ester of 2-norbornene-5-methyl-5-carboxylic acid. The polymerization reaction time is here 45 minutes and the polymer yield (soluble in benzene) is on the order of 73%.

j Example 5

Example 4 is carried out using the ethyl ester of 2-norbornene-5-carboxylic acid as monomers repeated. A 76% yield of polymer is obtained, which in benzene and carbon tetrachloride is soluble.

Example 6

Example 3 is carried out using 2-norbornene-5-chloride as the monomer in place of the Nitrile repeated again one obtains a ring-opened one Polymer.

Example 7

100 g of 5-acetoxy-2-norbornene are diluted in a flask under a nitrogen blanket with 400 cm ^{3 of} toluene. 8 m-moles of tungsten hexachloride, dissolved in 100 cm ^{3 of} benzene, and 8 m-moles of ethanol, dissolved in 50 cm ^{3 of} benzene, are then added and the contents of the flask are flushed with nitrogen to remove the HCl, which is produced by reaction between WCU and Ethanol is released. Thereafter, 40 m-moles of ethylenium sesquichloride, dissolved in 4C cm ^{3 of} hydrogenated isobutene trimers, are added. The following polymerization reaction is allowed to proceed for 20 minutes at a temperature of 60 ° C. and then it is terminated by adding 50 cm ^{3 of} a mixture of 1 g of 2,2'-methylene-bis- [4,4'-dimethyl-6, 6 '- (1-methylcyclohexyl)] phenol (antioxidant), ethanolamine (3 g), ethanol (20 g) and benzene (100 cm ³ ). The resulting polymer is recovered in 60% yield and it has an inherent viscosity of 1.3.

Example 8

Example 7 is repeated with the only difference that the reaction mixture contains 20 m-mol of octene-1 having. The resulting polymer has an inherent viscosity of 0.32, which is the chain termination effect of the incorporated acyclic monoolefin is demonstrated.

In all examples, the polymers as those of the polyalkenamer class (ie open ring) are positively identified by analytical techniques, which include nuclear magnetic resonance spectroscopy
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Claims (1)

Claim: Process for the preparation of homo- and copolymers of the polyalkenamer class by polymerization a norbo-nene, which is an esterified hydroxyl or carboxyl group, a halogen atom or a nitrile group in the 5-position or connected to the 5-position via an alkylene radical contains, where optionally the 5-position is an alkyl group with 1 to 6 as a further substituent May have carbon atoms in the presence of a metallic catalyst system in the liquid phase, characterized in that the catalyst system used is one which is characterized by Conversion of tungsten halides, molybdenum or tantalum with alcohols and organometallic Compounds of a metal of group Ia, Ha, Hb or IHa of the periodic table is obtained.