Process for preparation of catalytic components for polymerization of .alpha.-olefins

A process for preparation of a component of a catalyst for polymerization of .alpha.-olefins comprising adding (a) oxygen and the reaction product of titanium tetrachloride and an organic ether, to (b) titanium trichloride or to a composition of titanium trichloride and a metal halide, and milling the mixture.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates generally to a catalyst and more 
particularly, to a specific component of a catalyst used for 
polymerization of .alpha.-olefins in high yield and a process for the 
preparation thereof. 
2. Description of the Prior Art 
It is known in the art that catalytic components formed by pulverising pure 
titanium trichloride can be used for polymerization of .alpha.-olefin 
having at least 3 carbon atoms, as for example, propylene. These 
components can be obtained by reducing titanium tetrachloride with 
hydrogen or metallic titanium; by pulverising a solid chloride having a 
composition corresponding substantially equal to Ti.sub.3 Al Cl.sub.12, 
which is obtained by reducing titanium tetrachloride with metallic 
aluminum; or by pulverising a mixture of pure titanium trichloride or the 
solid chloride having the composition corresponding substantially equal to 
Ti.sub.3 Al Cl.sub.12 with an organic ether and/or other known components 
such as an electron-donative compound. 
In the preparation of a polymer of .alpha.-olefin, e.g., polypropylene, 
when the yield of the crystalline form of the high-polymer is improved, 
there is also a concomitant improvement in the yield of the overall final 
product and in the quality of the final product. Conventionally, in 
polymerization of .alpha.-olefins, the yield of the crystalline polymer is 
more greatly influenced by changes in the properties of the catalytic 
component than it is by correspondingly significant changes in either the 
polymerization conditions or the polymerization method. However, the yield 
is influenced to some extent by the choice of polymerization method or 
polymerization conditions. Therefore, the improvement of the properties of 
the catalytic component is a significant problem not only to manufacturers 
of catalysts, but also to manufacturers of polypropylene. 
The present inventor proposed a process for the preparation of a catalytic 
component for polymerization of .alpha.-olefins which included the steps 
of forming the reaction product of titanium tetrachloride and an organic 
ether, adding it to titanium trichloride or a composition comprising 
titanium trichloride and a metal halide, and then conducting a pulverising 
treatment. While this technique did improve the properties of the final 
product of the reaction, it still was not totally satisfactory. 
Consequently, it would be most desirable to have a new catalyst which 
further improves the product quality. 
SUMMARY OF THE INVENTION 
Accordingly, it is an object of this invention to provide a component of a 
catalyst used for polymerization of an .alpha.-olefin which enables 
production of crystalline polymers in high yields. 
This and other objects of this invention as will hereinafter be made clear 
by the ensuing discussion, have been attained by providing a process for 
polymerization of .alpha.-olefins which uses an .alpha.-olefin 
polymerization catalyst comprising a catalytic component formed by adding 
(a) oxygen and the reaction product of titanium tetrachloride and an 
organic ether, to (b) titanium trichloride or to a composition comprising 
titanium trichloride and a metal halide (hereinafter referred to as a 
composition of titanium trichloride) and subjecting this component to a 
milling treatment. When this product is used as a catalyst, the proportion 
of the crystalline polymer formed to the total polymer producted is 
surprisingly improved over that of the prior methods using conventional 
catalytic components.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Suitable compositions of titanium trichloride according to the present 
invention include those compounds obtained by reducing a titanium halide 
of the maximum valency, according to conventional methods. Suitable 
reducing agents include hydrogen, metallic titanium, metallic aluminum, 
metal hydrides such as sodium hydride, magnesium hydride or silicon 
hydrides (silanes), and organometallic compounds, such as organic aluminum 
compounds including triethyl aluminum and dialkyl aluminum halogenides. 
The reaction product having the composition corresponding substantially to 
Ti.sub.3 Al Cl.sub.12, which is prepared by reacting about 3 moles of 
titanium tetrachloride with about 1 mole of metallic aluminum, is 
especially preferred for use as the composition of titanium trichloride. 
Suitable organic ethers for use in this invention include organic ethers 
having at least one ether group in the molecule. Such organic ethers 
include lower dialkyl ethers such as diethylether, n-propylether, 
isobutylether, methylbutylether and the like; ethers obtained from 
alkylene glycol or polymers thereof such as ethylene glycol 
monoethylether, diethylene glycol dimethylether, triethylene glycol and 
the like; dioxanes such as 1,4 dioxane, 2 methyl 1,3 dioxane and the like; 
alkylarylethers such as anisole, parapropenylanisole and the like; and 
diarylethers such as diphenylether and the like. Quantitative differences 
in the end product are caused by variations in the kind of ether used. The 
most satisfactory effect is obtained when the lower dialkyl ethers, the 
alkylarylethers or the organic ethers obtained from alkylene glycol or a 
polymer thereof are employed. 
The reaction product of titanium tetrachloride and the organic ether 
according to the present invention is obtained by the reaction of titanium 
tetrachloride and the organic ether at temperatures in the range of from 
that at which the ether is in the liquid state to the boiling point of the 
ether. It is preferred that the titanium tetrachloride to be used in this 
invention be sufficiently purified. Also, oxygen gas of a high purity is 
preferred for use in this invention. 
The addition of oxygen and the reaction product can occur at any time 
before, after or during the milling treatment of the composition of 
titanium trichloride, so long as the composition of titanium trichloride, 
oxygen and the reaction product are sufficiently reacted and uniformly 
mixed. 
Suitable pulverizers for use in the milling treatment according to the 
present invention include conventional pulverizers which have been used in 
the past for the fine pulverization of powder such as a ball mill, a 
vibration mill, an aerofoil mill, a tower type grinder, a ring mill, an 
impact grinder and the like. The amount of time required for the milling 
treatment can be determined by the conventional techniques well known to 
those skilled in the art. The period will depend on the type of 
pulverizers used in the milling treatment and the medium being pulverized. 
The milling treatment is preferably conducted in an atmosphere of an inert 
gas at a temperature of -20.degree. C. to +80.degree. C., preferably 
0.degree. C. to 60.degree. C. The inert gas atmosphere, of course, is not 
necessary when the milling is performed during the addition of the oxygen. 
The molar concentration of oxygen should be 0.1 to 5 mole %, based on the 
number of moles of the composition of titanium trichloride. When the 
amount of oxygen exceeds 5 mole %, the catalytic activity is drastically 
lowered and the yield of the crystalline polymer is reduced. When the 
amount of oxygen is smaller than 0.1 mole %, the oxygen addition has no 
substantial effect. 
The amount of the reaction product relative to the amount of the 
composition of titanium trichloride should be 0.1 to 30 weight %, 
preferably 1 to 15 weight %. In the reaction product titanium 
tetrachloride should be present within 0&lt;titanium tetrachloride &lt;100 
weight %, preferably 1 to 70 weight % relative to the amount of organic 
ether. 
The titanium compound catalytic component according to this invention 
constitutes a catalyst, together with an organic aluminum compound, known 
as a component of a Ziegler type catalyst. It can also be used with the 
aluminum compound, with other known catalytic components such as an 
electron-donative compound. In either form it is very effective for 
polymerization of .alpha.-olefins. 
Having generally described the invention, a more complete understanding can 
be obtained by reference to certain specific examples, which are included 
for purpose of illustration only and are not intended to be limiting 
unless otherwise specified. 
EXAMPLE 1 
200 g of a composition of titanium trichloride having a formula 
substantially equal to Ti.sub.3 Al Cl.sub.12 is charged into a vibration 
mill with a 1.0 liter inner capacity. The mill has an argon gas atmosphere 
and contains a 0.8 liter apparent volume of 12mm .phi. steel balls. The 
composition of titanium trichloride is milled at 35.degree. C. for 30 
hours in the atmosphere of argon. Then a reaction product formed between 
10g of diethylether and 2g of titanium tetrachloride is admixed therewith 
and further milled at 35.degree. C. for 5 hours. 1 mole % of oxygen gas 
based on the number of moles of the composition of titanium trichloride is 
then charged into the mill and further milled at 35.degree. C. for 5 
hours. A catalytic component is obtained. 
A 1.5 liter stainless steel autoclave is filled with argon and loaded with 
0.5g of the resulting catalytic component, 0.75g of diethyl aluminum 
monochloride and 500 ml of n-heptane. The autoclave is heated to 
70.degree. C., 200 ml of hydrogen is fed and propylene is fed into the 
autoclave. The propylene is polymerized at a propylene partial pressure of 
6.03 Kg/cm.sup.2 G at 70.degree. C. for 2 hours. 
After the polymerization is stopped by adding butanol into the autoclave, 
the contents of the autoclave are sufficiently shaken to decompose the 
catalyst and filtered. Then, the solid reactants are washed with a mixture 
of isopropanol and methanol and dried in vacuo to yield a solid polymer. 
The amount of the resulting polymer is designated as (B). 
Then, the resulting solid polymer is extracted with boiling heptane for 6 
hours to yield a heptane insoluble polymer. The amount of the heptane 
insoluble polymer is designated as (C). 
The amount of polymer remaining in the solvent is designated as (A). The 
yield of the isotactic polymer (D) can thus be calculated by the formula: 
EQU D=C/(A+B).times.100 
the polymerization activity (E) of the catalyst can be calculated by the 
formula: 
EQU E=A+B/amount of catalyst 
The yield of atactic polymer can be calculated by the formula: 
EQU 100-D 
the results are shown in Table 1. 
EXAMPLE 2 
The experiment is conducted in the same manner as in Example 1 except that 
1 mole % of oxygen based on the number of moles of the composition of 
titanium trichloride is added prior to initiation of the milling treatment 
of the composition of titanium trichloride. Then the milling treatment is 
conducted for 35 hours. A reaction product derived from 8 g of 
diethylether and 2 g of titanium tetrachloride is added and the milling 
treatment is conducted for 5 hours to obtain a catalytic component. 
Results obtained are shown in Table 1. 
EXAMPLE 3 
The experiment is conducted in the same manner as in Example 1 except that 
a reaction product derived from 18 g of diethylether and 3 g of titanium 
tetrachloride is added prior to the milling treatment of the composition 
of titanium trichloride (having a composition corresponding substantially 
to Ti.sub.3 Al Cl.sub.12). 
The milling treatment is conducted for 10 hours, 1 mole % of oxygen based 
on the number of moles of the composition of titanium trichloride is added 
and then the milling treatment is further conducted for 30 hours to obtain 
a catalytic component. Results obtained are shown in Table 1. 
EXAMPLE 4 
The experiment is conducted in the same manner as in Example 1 except that 
1 mole % of oxygen based on the number of moles of the composition of 
titanium trichloride is added prior to the milling treatment of the 
composition of titanium trichloride (having a composition corresponding 
substantially to Ti.sub.3 Al Cl.sub.12). The milling treatment is 
conducted for 20 hours. A reaction product derived from 16 g of 
diethylether and 4 g of titanium tetrachloride is added and the milling 
treatment is conducted for 20 hours to obtain a catalytic component. 
Results obtained are shown in Table 1. 
EXAMPLE 5 
The experiment is conducted in the same manner as in Example 1 except that 
a reaction product derived from 6 g of diethylether and 3 g of titanium 
tetrachloride and 1 mole % of oxygen based on the number of moles of the 
composition of titanium trichloride are added prior to the milling 
treatment of the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3 Al Cl.sub.12). Then the milling 
treatment is carried out for 40 hours to obtain a catalytic component. 
Results obtained are shown in Table 1. 
EXAMPLE 6 
The experiment is conducted in the same manner as in Example 1 except that 
1 mole % of oxygen based on the number of moles of the composition of 
titanium trichloride is added prior to the milling treatment of the 
composition of titanium trichloride (having a composition corresponding 
substantially to Ti.sub.3 Al Cl.sub.12). The milling treatment is 
conducted for 20 hours. A reaction product derived from 12 g of diethyl 
glycol dimethylether and 2 g of titanium tetrachloride is added and the 
milling treatment is conducted for 20 hours to obtain a catalytic 
component. Results obtained are shown in Table 1. 
EXAMPLE 7 
The experiment is conducted in the same manner as in Example 1 except that 
a reaction product derived from 10 g of anisole and 2 g of titanium 
tetrachloride is added prior to the milling treatment of a composition of 
titanium trichloride (having a composition corresponding substantially to 
Ti.sub.3 Al Cl.sub.12). The milling treatment is conducted for 35 hours. 1 
mole % of oxygen based on the number of moles of the composition of 
titanium trichloride is added and the milling treatment is further 
conducted for 5 hours to obtain a catalytic component. Results obtained 
are shown in Table 1. 
EXAMPLE 8 
The experiment is conducted in the same manner as in Example 1 except that 
0.15% of oxygen gas based on the number of moles of the composition of 
titanium trichloride is added. Results obtained are shown in Table 1. 
EXAMPLE 9 
The experiment is conducted in the same manner as in Example 1 except that 
5 mole % of oxygen gas based on the number of moles of the composition of 
titanium trichloride is added. Results obtained are shown in Table 1. 
EXAMPLE 10 
The experiment is conducted in the same manner as in Example 1 except that 
the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3.5 Al Cl.sub.13.5 is subjected to a 
milling treatment for 10 hours. Then a reaction product formed between 16 
g of diethylether and 2g of titanium tetrachloride is admixed therewith 
and further milled for 25 hours. One (1) mole % of oxygen based on the 
number of moles of the composition of titanium trichloride is then added 
and further milled for 5 hours. A catalytic component is obtained. Results 
obtained are shown in Table 1. 
EXAMPLE 11 
The experiment is conducted in the same manner as in Example 1 except that 
1 mole % of oxygen gas based on the number of moles of the composition of 
titanium trichloride is added prior to the milling treatment of titanium 
trichloride (having a composition corresponding substantially to 
Ti.sub.2.5 Al Cl.sub.10.5). The milling treatment is conducted for 30 
hours. A reaction product derived from 18g of diethylether and 2g of 
titanium tetrachloride is then added and the milling treatment is 
conducted for 10 hours to obtain a catalytic component. Results obtained 
are shown in Table 1. 
COMATIVE EXAMPLE 1 
The experiment is conducted in the same manner as in Example 1 except that 
the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3 Al Cl.sub.12) is subjected to a 
milling treatment for 35 hours. 5 g of diethylether alone is added instead 
of oxygen and the diethylether-titanium tetrachloride reaction product. 
Then the milling treatment is further conducted for 5 hours to obtain a 
catalytic component. Results obtained are shown in Table 2. 
COMATIVE EXAMPLE 2 
The experiment is conducted in the same manner as in Comparative Example 1 
except that 20 g of diethylether is added prior to the milling treatment 
of the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3 AlCl.sub.12). Then the milling 
treatment is conducted for 40 hours to obtain a catalytic component. 
Results obtained are shown in Table 2. 
COMATIVE EXAMPLE 3 
The experiment is conducted in the same manner as in Example 1 except that 
the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3 AlCl.sub.12 is subjected to a 
milling treatment for 20 hours. 2 g of titanium tetrachloride and 8 g of 
diethylether are individually but simultaneously added instead of oxygen 
and the diethylether-titanium tetrachloride reaction product. The milling 
treatment is conducted for 20 hours to obtain a catalytic component. 
Results obtained are shown in Table 2. 
COMATIVE EXAMPLE 4 
The experiment is conducted in the same manner as in Comparative Example 3 
except that the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3 Al Cl.sub.12) is subjected to a 
milling treatment for 30 hours. 16 g of diethylether and 4 g of titanium 
tetrachloride are added individually but simultaneously and the milling 
treatment is then conducted for 10 hours to obtain a catalytic component. 
Results obtained are shown in Table 2. 
COMATIVE EXAMPLE 5 
The experiment is conducted in the same manner as in Example 1 except that 
the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3 Al Cl.sub.12) is subjected to the 
milling treatment for 35 hours. 1 mole % of oxygen alone based on the 
number of moles of the composition of titanium trichloride is added 
instead of oxygen and the diethylether-titanium tetrachloride reaction 
product. The milling treatment is conducted for 5 hours to obtain a 
catalytic component. Results obtained are shown in Table 2. 
COMATIVE EXAMPLE 6 
The experiment is conducted in the same manner as in Example 1 except that 
the composition of titanium trichloride (having a composition 
corresponding substantially to Ti.sub.3 Al Cl.sub.12) is subjected to a 
milling treatment for 35 hours. A reaction product derived from 10 g of 
diethylether and 2.1 g of titanium tetrachloride is added instead of 
oxygen and the diethylether-titanium tetrachloride reaction product. The 
milling treatment is then conducted for 5 hours to obtain a catalytic 
component. Results obtained are shown in Table 2. 
COMATIVE EXAMPLE 7 
The experiment is conducted in the same manner as in Comparative Example 6 
except that prior to the milling treatment of the composition of titanium 
trichloride (having a composition corresponding substantially to Ti.sub.3 
Al Cl.sub.12) a reaction product derived from 10 g of diethylether and 2.1 
g of titanium tetrachloride is added. The milling treatment is conducted 
for 40 hours to obtain a catalytic component. Results obtained are shown 
in Table 2. 
COMATIVE EXAMPLE 8 
The experiment is conducted in the same manner as in Comparative Example 1 
except that 0.05 mole % of oxygen gas based on the number of moles of the 
composition of titanium trichloride is added. Results obtained are shown 
in Table 2. 
COMATIVE EXAMPLE 9 
The experiment is conducted in the same manner as in Comparative Example 1 
except that 6 mole % of oxygen gas based on the number of moles of the 
composition of titanium trichloride is added. Results obtained are shown 
in Table 2. 
From the results shown in Tables 1 and 2, it can easily be seen that when 
polymerization is carried out by using a catalyst comprising a catalytic 
component prepared according to the process of this invention, the yield 
of the crystalline polymer is significantly improved over the yield of the 
crystalline polymer obtained when polymerization is carried out by using a 
catalyst comprising a catalytic component prepared according to a method 
outside the scope of this invention. 
Table 1 
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Experimental Results 
__________________________________________________________________________ 
Example 
Example 
Example 
Example 
Example 
Example 
Example 
Example 
Example 
1 2 3 4 5 6 7 8 9 
__________________________________________________________________________ 
Amount (A)g of 
Polymer Remaining in 
2.1 2.3 2.3 2.4 2.6 2.5 2.6 2.5 2.3 
Polymerization Solvent 
Amount (B)g of 
211.2 
206.8 
207.5 
200.4 
203.3 
201.8 
204.2 
209.5 
195.0 
Solid Polymer 
Amount (C)g of 
Boiling Heptane- 
209.5 
204.9 
205.4 
198.3 
200.8 
200.1 
201.8 
207.1 
202.0 
Insoluble Polymer 
Yield (D)% of 
Isotactic Polymer, 
##STR1## 98.2 
98.0 
97.9 
97.8 
97.5 
97.9 
97.6 
97.7 
97.4 
Polymerization 
Activity (E) of 
Catalyst, 
##STR2## 426.6 
418.2 
419.6 
405.6 
411.8 
408.6 
413.6 
424.0 
394.6 
Yield % of Atactic 
Polymer, 1.8 2.0 2.1 2.2 2.5 2.1 2.4 2.3 2.6 
(100 - D) 
Example 
Example 
10 11 
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Amount (A)g of 
Polymer Remaining in 
2.4 2.5 
Polymerization Solvent 
Amount (B)g of 
Solid Polymer 
201.9 
201.8 
Amount (C)g of 
Boiling Heptane- 
199.8 
199.4 
Insoluble Polymer 
Yield (D)% of 
Isotactic Polymer, 
##STR3## 97.8 
97.6 
Polymerization Activity (E) of 
Catalyst, 
##STR4## 410.4 
408.6 
Yield % of Atactic 
Polymer, 2.2 2.4 
(100 - D) 
__________________________________________________________________________ 
table 2 
__________________________________________________________________________ 
Experimental Results 
__________________________________________________________________________ 
Comparative 
Comparative 
Comparative 
Comparative 
Comparative 
Comparative 
Comparative 
Example 1 
Example 2 
Example 3 
Example 4 
Example 5 
Example 
Example 
__________________________________________________________________________ 
7 
Amount (A)g of 
Polymer Remaining in 
5.5 5.7 4.0 3.6 7.6 2.9 3.2 
Polymerization Solvent 
Amount (B)g of 
Solid Polymer 198.8 197.9 197.2 198.9 191.7 200.9 198.7 
Amount (C)g of 
Boiling Heptane- 
193.3 193.0 192.3 194.0 185.7 197.3 195.2 
Insoluble Polymer 
Yield (D)% of 
Isotactic Polymer, 
##STR5## 94.6 94.8 95.6 95.8 93.2 96.8 96.7 
Polymerization 
Activity (E) of 
Catalyst, 
##STR6## 408.6 407.2 402.4 405.0 398.6 407.6 403.8 
Yield % of 
Atactic Polymer, 
5.4 5.2 4.4 4.2 6.8 3.2 3.3 
(100 - D) 
Comparative 
Comparative 
Example 8 
Example 9 
__________________________________________________________________________ 
Amount (A)g of 
Polymer Remaining in 
3.5 6.0 
Polymerization Solvent 
Amount (B)g of 
Solid Polymer 200.0 124.8 
Amount (C)g of 
Boiling Heptane- 
197.0 120.6 
Insoluble Polymer 
Yield (D)% of 
Isotactic Polymer, 
96.8 92.2 
##STR7## 
Polymerization 
Activity (E) of 
Catalyst, 
##STR8## 407.0 261.6 
Yield % of 
Atactic Polymer, 
3.2 7.8 
(100 - D) 
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having now fully described this invention, it will be apparent to one of 
ordinary skill in the art that many changes and modifications can be made 
thereto without departing from the spirit or scope of the invention as set 
forth herein.