POLYMERIZATION PROCESS FOR LIQUID COPOLYMERS OF ETHYLENE AND GLYCIDYL (METH)ACRYLATE

Abstract

The present invention relates to a continuous high-pressure polymerization process for the preparation of a liquid ethylene copolymer which comprises in polymerized form ethylene; and more than 10 wt % of a reactive acrylate which is selected from glycidyl acrylate and glycidyl methacrylate, where a monomer feed comprising the ethylene and the reactive acrylate is polymerized in the presence of at least 2 wt % of a chain transfer agent.

Claims

1.-16. (canceled)

17. A continuous high-pressure polymerization process for the preparation of a liquid ethylene copolymer which comprises in polymerized form ethylene; and more than 10 wt. % of a reactive acrylate which is selected from glycidyl acrylate and glycidyl methacrylate, where a monomer feed comprising the ethylene and the reactive acrylate is polymerized in the presence of at least 2 wt. % of a chain transfer agent.

18. The polymerization process according to claim 17, where the chain transfer agents are saturated or unsaturated hydrocarbons, aliphatic ketones, aliphatic aldehydes, or hydrogen, or mixtures thereof.

19. The polymerization process according to claim 17, where the monomer feed is polymerized in the presence of 4 to 18 wt. % of the chain transfer agent.

20. The polymerization process according to claim 17, where the polymerization process is carried out at a pressure in the range from 1000 to 4000 bar.

21. The polymerization process according to claim 17, where the ethylene copolymer has a pour point below 25 C.

22. The polymerization process according to claim 17, where the ethylene copolymer comprises in polymerized form 20 to 80 wt. % of the ethylene.

23. The polymerization process according to claim 17, where the ethylene copolymer comprises in polymerized form 11 to 70 wt. %.

24. The polymerization process according to claim 17, where the ethylene copolymer comprises in polymerized form 30 to 80 wt. % of ethylene, and 20 to 70 wt. % of the reactive acrylate.

25. The polymerization process according to claim 17, where the ethylene copolymer comprises in polymerized form an alkyl (meth)acrylate which is selected from C.sub.1-C.sub.22 alkyl (meth)acrylate.

26. The polymerization process according to claim 25, where the alkyl (meth)acrylate is selected from C.sub.1-C.sub.6 alkyl (meth)acrylate.

27. The polymerization process according to claim 25, where the ethylene copolymer comprises from 10 to 65 wt. % of the alkyl (meth)acrylate.

28. The polymerization process according to claim 25, where the ethylene copolymer is free of further monomers beside the ethylene, the reactive acrylate, and the alkyl (meth)acrylate.

29. The polymerization process according to claim 25 where the ethylene copolymer comprises in polymerized form 20 to 70 wt. % of ethylene, 12 to 60 wt. % of the reactive acrylate, and 5 to 70 wt. % of the alkyl (meth)acrylate, which is selected from C.sub.1-C.sub.6 alkyl (meth)acrylate.

30. A liquid ethylene copolymer as defined in claim 17.

31. A coating material comprising the liquid ethylene copolymer as defined in claim 17.

32. A use of the liquid ethylene copolymer as defined in claim 17 to produce a coating material.

Description

EXAMPLES

[0137] Preparation of Copolymers

[0138] A high-pressure autoclave, of the type described in the literature (M. Buback et al., Chem. Ing. Tech. 1994, 66, 510-513) was used for continuous copolymerization

[0139] Ethylene was fed continuously into a first compressor until approx. 250 bar. Separately from this, the amount of glycidyl methacrylate GMA was also compressed continuously to an intermediate pressure of 250 bar and was mixed with the ethylene fed. The ethylene acrylate mixture was further compressed using a second compressor. The reaction mixture is brought to a 1 liter autoclave with pressure and temperatures given also according to Table 1. The desired temperature is controlled depending on the amount of initiator tert-amyl peroxypivalate in isodecane, which is introduced to the autoclave separately from the monomer feed (about 1000-1500 ml/h).

[0140] Separately from this, the amount of chain transfer agent (propionaldehyde (PA) or methyl ethyl ketone (MEK)) was first compressed to an intermediate pressure of 250 bar and then fed continuously into the high-pressure autoclave with the aid of a further compressor under the reaction pressure.

[0141] The output of the reactions in Table 1 was usually around 5-6 kg/h at a conversion of 30 to 45 wt % (based on ethylene feed). Details of the reaction conditions were summarized in Table 1 and the analytical data of the liquid ethylene copolymers are summarized in Table 2. The regulator feed in Table 1 refers to propionaldehyde if nothing else is indicated.

TABLE-US-00001 TABLE 1 Preparation of liquid ethylene copolymers P T Ethylene Acrylate Regulator Ex. Monomers [bar] [ C.] Feed Feed Feed 1 E-GMA 1700 220 12060 g/h 1380 g/h PA: 590 g/h (4.2 wt %) 2 E-GMA-MMA 1700 220 11990 g/h GMA: 1500 g/h PA: 990 g/h (6.2 wt %) MMA: 1490 g/h MEK: 1490 g/h (8.5 wt %) 3 E-GMA-MMA 1700 220 12000 g/h GMA: 1490 g/h PA: 1000 g/h (5.5 wt %) MMA: 1855 g/h MEK: 1855 g/h (10.1 wt %) 4 E-GMA-NBA 1700 220 11840 g/h GMA: 1350 g/h PA: 1490 g/h (7.9 wt %) NBA: 3990 g/h 5 E-GMA 1700 220 12050 g/h GMA: 3100 g/h PA: 1500 g/h (9.0 wt %) 6 E-GMA 1700 220 11980 g/h GMA: 3180 g/h PA: 2000 g/h (11.6 wt %) 7 E-GMA-NBA 1700 220 12060 g/h GMA: 2090 g/h PA: 1990 g/h (10.3 wt %) NBA: 3080 g/h 8 E-GMA-NBA 1700 220 11950 g/h GMA: 2030 g/h PA: 2000 g/h (10.5 wt %) NBA: 3000 g/h 9 E-GMA-NBA 1700 220 11930 g/h GMA: 3030 g/h PA: 2000 g/h (10.0 wt %) NBA: 3000 g/h 10 E-GMA-NBA 1700 220 11990 g/h GMA: 3050 g/h PA: 2000 g/h (10.5 wt %) NBA: 2000 g/h 11 E-GMA-NBA 1700 220 12000 g/h GMA: 3490 g/h PA: 2000 g/h (10.5 wt %) NBA: 1500 g/h

[0142] Characterization of the Liquid Ethylene Copolymers

[0143] The molecular weight number distribution Mn and the molecular weight weight distribution Mw were determined via GPC. The polydispersity was calculated as PD=(M.sub.w/M.sub.n). The GPC analysis was made with a RI detector, a PLgel MIXED-B column (column temperature 35 C.) and THF with 0.1% trifluor acetic acid as elution medium. The calibration was done with very narrow distributed polystyrene standards from the Polymer Laboratories with a molecular weights M=from 580 until 6.870.000 g/mol.

[0144] The Cloud Point CP was determined according to ISO 3015. The Pour Point PP was determined according to ASTM D 97.

[0145] The results demonstrated that all ethylene copolymers were liquid at room temperature and had a pour point below 25 C.

[0146] The results further indicate that all ethylene copolymers tend to have good low temperature characteristics because of their low cloud point.

[0147] The amounts of monomomers which are present in polymerized form in the polymer was determined by H-NMR.

[0148] The Kinematic Viscosity at 120 C. (V120) were determined according to ASTM D 445. The appearance of the liquid ethylene copolymers was determined visually.

[0149] The results demonstrated that the ethylene copolymers have a desired high kinematic viscosity and is liquid at room temperature.

TABLE-US-00002 TABLE 2 Analytical data of copolymers Amounts Mn Mw V120 Ex. Monomers [wt %] [g/mol] [g/mol] PD [mm.sup.2/s] 1 E-GMA 63-37 3300 8070 2,4 400 2 E-GEMA-MMA 46-26-28 2610 5620 2,2 280 3 E-GMA-MMA 42-23-35 2660 5750 2,2 370 4 E-GMA-NBA 33-17-50 2640 6320 2,4 140 5 E-GMA 46-54 2360 4910 2,1 170 6 E-GMA 46-54 1930 3850 2 100 7 E-GMA-NBA 34-27-38 2440 5260 2,2 95 8 E-GMA-NBA 36-27-37 2530 5220 2,1 100 9 E-GMA-NBA 32-34-33 2720 5760 2,1 150 10 E-GMA-NBA 35-29-25 2490 5060 2 130 11 E-GMA-NBA 35-45-20 2480 5100 2,1 150