JPH0222310A - Production of propylene copolymer - Google Patents

Abstract

PURPOSE:To efficiently obtain the title copolymer useful for bonding, etc., by copolymerizing propylene with an alkenylsilane by using a specific stereoregular catalyst, separating unreacted monomers from the formed copolymer and using the monomers for the next polymerization. CONSTITUTION:First, propylene is copolymerized with an alkenylsilane (e.g., vinylsilane) by using a catalyst consisting of a transition metal catalyst prepared by supporting a titanium halide on a magnesium halide and an organoaluminum compound as a stereoregular catalyst in the presence of an inert hydrocarbon medium (e.g., pentane). Then, after the polymerization reaction is over, unreacted monomers are separated from the formed copolymer and used for the next polymerization as they are. The ratio of the alkenylsilane and propylene is preferably <=30mol% alkenylsilane with respect to catalytic activity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a copolymer of propylene. Specifically, the present invention relates to a method for efficiently producing a copolymer of propylene and alkenylsilane.

[Prior art]

Alkenylsilane is polymerized using a Ziegler-Natsuta catalyst consisting of a transition metal catalyst and an organometallic compound, and copolymers with olefins such as propylene can be crosslinked with water and are said to be useful as crosslinked polyolefins (
USP3223686. Although not previously known, these copolymers are extremely useful not only as crosslinked polyolefins but also for adhesives, coatings, etc., although they were not previously known.

[Problem to be solved by the invention]

As mentioned above, copolymers of alkenylsilane are extremely useful copolymers, especially copolymers with propylene, but alkenylsilane is not only expensive but also relatively difficult to copolymerize with olefins. Conventional methods have had the problem that copolymers are expensive and their use is limited.

[Means to solve the problem]

The inventors of the present invention have completed the present invention by intensively studying methods for solving the above problems.

That is, the present invention provides a method for producing a copolymer of propylene and alkenylsilane by copolymerizing propylene and alkenylsilane using a stereoregular catalyst, in which titanium halide is supported on magnesium halide as a stereoregular catalyst. Copolymerization of propylene and alkenylsilane is carried out using a catalyst consisting of a transition metal catalyst and an organoaluminum in the substantial absence of an inert hydrocarbon medium, and then, after the polymerization reaction, unreacted monomers are converted into propylene and alkenyl silane. This is a method for producing a propylene copolymer, which is characterized in that it is separated from a silane copolymer and used as it is in the next polymerization.

The present invention also provides a method for producing a copolymer of propylene and alkenylsilane by copolymerizing propylene and alkenylsilane using a stereoregular catalyst. Copolymerization of propylene and alkenylsilane is carried out using a catalyst consisting of a metal catalyst and an organoaluminum using a bulk polymerization method using propylene as a liquid medium. After the polymerization reaction,
This propylene copolymerization method is characterized in that unreacted monomers are separated into solid and liquid from the copolymer and used in the next polymerization.

The alkenylsilane used in the present invention has at least one 5i-H bond, such as vinylsilane, allylsilane, butenylsilane, pentenylsilane, and one of the 5t-H bonds of these monomers.
Examples include those in which ~2 of the substituents are substituted with alkyl groups.

As the stereoregular catalyst used in the present invention, a catalyst system consisting of a transition metal catalyst and an organometallic compound is used, and as the transition metal catalyst, a catalyst in which titanium halide is supported on magnesium halide is used. As a catalyst in which titanium halide is supported on magnesium halide, various improved methods have been known since it was disclosed in Japanese Patent Publication No. 39-12105, and there are no restrictions on the manufacturing method, but for example, magnesium halide or its unmixed catalyst can be used. A catalyst obtained by supporting a titanium halide on another active support or a co-pulverization thereof with an electron-donating compound, or a reaction product of a magnesium halide and an alcohol is dissolved in a hydrocarbon solvent, and then the halogen It is treated with a precipitant such as titanium chloride to make it insoluble in a hydrocarbon solvent, and if necessary, treated with an electron-donating compound such as an ester or ether at some stage after dissolving the magnesium halide. An example is a catalyst system consisting of a catalyst obtained by a method such as a method of treating with organic aluminum, an organoaluminum compound, and, if necessary, a stereoregularity improver such as an oxygen-containing organic compound (for example, various examples are described in the following literature). Ziegler-Natta Catalysts
and Polymerization by
John Boor Jr.
c Press), Journal of Mac
romorecular 5ienceRevie@s
in Macrosolecular Che
mistry and physics, C24
(3), 355-385 (1984), C25 (1
), 578-597 (1985)).

Preferred examples of stereoregularity improvers or electron-donating compounds include oxygen-containing compounds such as ethers, esters, orthoesters, alkoxy silicon compounds, or sterically hindered amines, and further examples of electron-donating compounds include alcohols, aldehydes, Water can also be used.

One component, the organoaluminum compound, is
Trialkylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide, and alkylaluminium civalide can be used; examples of the alkyl group include methyl group, ethyl group, propyl group, butyl group, and hexyl group; and examples of the halide include chlorine and bromine. ,
An example is iodine.

In the present invention, polymerization includes penkune, hexane, heptane,
The conditions used for ordinary propylene polymerization are sufficient as zero polymerization conditions for bulk polymerization and gas phase polymerization that do not substantially use inert solvents such as nonane, decane, benzene, toluene, etc. There are no restrictions, usually at room temperature ~
It is generally carried out at a temperature of 150°C and a pressure of normal pressure to 100 kg/cm''.The polymerization ratio of alkenylsilane and propylene is particularly determined as long as the resulting polymer maintains crystallinity. Although there is no limit, the alkenylsilane content is usually 30 mol% or less to improve the catalyst activity during polymerization.
Alternatively, it is preferred for use as a copolymer.

Also, as long as it maintains crystallinity, other olefins, such as
Ethylene, butene-1, hexene-1, etc. may be polymerized randomly or in a block manner, and usually when polymerized randomly, the olefin is 10 wt% or less,
When polymerizing in a block manner, the mixing ratio of monomers during polymerization should be set to 30 wt% or less. Further, in order to control the molecular weight of the polymer, hydrogen can be present in a desired amount during polymerization.

In the present invention, after the polymerization reaction, the unreacted monomer can be recovered by evaporation and separated from the copolymer, and the separated gas can be re-agglomerated if necessary; A method of static separation, a method of separating the polymer with a cyclone, or a method of washing with propylene in a countercurrent washing tower, recovering unreacted propylene, alkenylsilane, and organic aluminum from the upper part of the tower, and discharging the copolymer propylene slurry from the lower part. An example is a method of recovering -.

At this time, in order to avoid uncontrolled polymerization as much as possible, it is preferable to carry out the reaction at a temperature lower than the polymerization temperature.

The recovered unreacted monomer is mixed with propylene, alkenylsilane and propylene in a desired ratio.
Alternatively, it can be reused as is by simply adding alkenylsilane. When the liquid phase is separated, find out the concentration of organoaluminum or electron donor in the recovered monomer and adjust the amount of organoaluminum or electron donor to be added during polymerization to achieve the optimum value during polymerization. It is preferable that the amount ratio is the same.

〔Example〕

The present invention will be further explained with reference to Examples below.

Example 1 Internal volume 20I! In an autoclave, 71 parts of refined kerosene, 100 g of magnesium chloride and 3 parts of 2-ethylhexanol were added.
70 g was added and stirred at 100°C for 24 hours to completely dissolve. After adding 23 g of phthalic anhydride and stirring, 407 g of titanium tetrachloride! 10 kept at -20°C
0! The mixture was added dropwise to the autoclave under stirring.

Thereafter, the temperature was slowly raised to 100°C, and 56d of diisobutyl phthalate was added thereto, and the mixture was treated for 1 hour. Next, remove the supernatant, add 202 ml of titanium tetrachloride, and add 10 ml of titanium tetrachloride.
The mixture was stirred at 0° C., and the solid content was finally washed 10 times with n-heptane to obtain a transition metal catalyst.

30 cm of the above transition metal catalyst was placed in an autoclave with an internal volume of 52 cm.
, 0.1 d of triethylaluminum, 0.03 d of diphenyljethoxysilane, 1 d of propylene, 51C
g, and 300 g of vinylsilane were added, followed by polymerization at 70°C for 2 hours. The temperature of the polymerization was lowered to 20°C, and 860 g of unreacted monomer was recovered through a siphon tube covered with a 200-mesh wire mesh. The recovered monomer was analyzed to contain 235 g of vinylsilane. In addition, the polymer taken out from the autoclave was dried and weighed 735g.
A copolymer of propylene with a vinylsilane content of 2.1 wtχ and an intrinsic viscosity of 1.95 as measured in a tetralin solution at 135°C was obtained.

Using the recovered monomers, 875 g of propylene and 65 g of vinyl silane were added to make the ratio of propylene and vinyl silane the same as in the above polymerization, and 0 of triethylaluminum was added.
．． 07d, diphenyljethoxysila: The same procedure as in Example 1 was carried out except that 10.02 m was used, and 728 g of polymer was taken out in the same manner, and it contained vinylsilane! 2.1w
tχ, the intrinsic viscosity was 1.89, and the reaction proceeded in substantially the same manner as the initial polymerization.

〔Effect of the invention〕

By carrying out the method of the present invention, a copolymer containing alkenylsilane can be efficiently obtained and is extremely valuable industrially.

Patent applicant Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. A method for producing a copolymer of propylene and alkenylsilane by copolymerizing propylene and alkenylsilane using a stereoregular catalyst, in which titanium halide is added to magnesium halide as the stereoregular catalyst. Copolymerization of propylene and alkenylsilane is carried out using a catalyst consisting of a supported transition metal catalyst and an organoaluminum in the substantially absence of an inert hydrocarbon medium, and then, after the polymerization reaction, unreacted monomers are converted into propylene. 1. A method for producing a copolymer of propylene, which is separated from a copolymer of propylene and alkenylsilane and used as it is in the next polymerization. 2. In a method for producing a copolymer of propylene and alkenylsilane by copolymerizing propylene and alkenylsilane using a stereoregular catalyst, a transition metal catalyst in which titanium halide is supported on magnesium halide is used as the stereoregular catalyst. Propylene and alkenylsilane are copolymerized using a catalyst made of organoaluminum using a bulk polymerization method using propylene as a liquid medium. After the polymerization reaction, unreacted monomers are separated from the copolymer by solid-liquid separation. A propylene copolymerization method characterized in that it is used in the following polymerization.