Note: Descriptions are shown in the official language in which they were submitted.
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1
SPECIFICATION
Method of Manufacturing Polyolefin Solutions
Field of the Invention
The present invention relates to a method ot' manufacturing a polyolefin
solution used for manufactuririQ microporous polyolefin nienibranes,
polyolefin
fibers and the like. More particularly, it relates to a method for
continuously
manufacturing a solution of polyolefin havin, a wide molecular distribution
range,
irl a stable manner and with a high output.
Bac arou d of the Invem.tion
A polyolefin resin has superior mechanical strength and physical
characteristics; therefore, it has been used for various purposes. For
example,
microporous polyolefin niembranes and porous fibers have been used as a
separator
for batteries, a separation film for electrolytic capacitors, precision
filters, air
filters and the like. A polyolefin resin is generally manufactured using a
polyolefin
solution incorporating an advanced flow iniprover or solvent.
The polyolefin solution is conventionally manufactured by means of
"batch" type kneading, continuous kneadin- and the like of a poiyolefin resin
and a
liquid such as mineral oil and the like. In the case of the batch kneading,
the
polyolefin and the liquid are put into an autoclave equippecl with a mixer,
the
temperature is increased while the mixture is mixed, and the polyolefin and
the
liquid are kneaded. However, with the batch kneading, the kneading time takes
longer, which is a short-coming. In addition, with the batch kneading the
residence
time differs between a product taken out from the batch at the initial stage
and that
toward the end, when the kneaded solution is taken out for use. As a result,
the
quality within the batch or at the time of switc.hinb the batch is not stable,
and
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2
furthermore, this method requires man power, which is another shortcoming. In
addition, it is difficult to prepare a high viscosity solution and it is not
possible to
use higb molecular weight compositions in the pellet form. This is a further
shortcoming.
Therefore, in recent years, a continuous type kneader equipped with a
liquid feed section downstream of a resin feed section has been used- for
manufacturing a polyolefin solution. However, in the prior art, the pressure
in the
kneader at the liquid feed section is high, and in additaon, the pressure at
the liquid
feed section is higher than the pressure downstream. For that reason, when the
quantity of supplied liquid is increased, the kneading of polyolefin cannot be
carried out sufficiently, and a liquid back-flow in the upstream direction is
observed. As a result it is necessary to reduce the quantity of the supplied
liquid. In
addition, the amount of shearing exothermic energy is large within the kneader
area
in which only the polymer exists, and this often results in deterioration of
the
polymer due to heat.
In view of the above, an object of the present invention is to provide a
manufacturing method in which a polyolefin solution can be continuously
obtained
with a high yield and in a stable manner.
Disclosure of the Invention
As a result of continuous research with the above purpose in mind, the
present inventors made the present invention, using a continuous kneader
having a
self-cleaning effect, and by maintaining a starving state within an internal
section of
the kneader at a polyolefin resin feed section, a liquid feed section and a
kneading
section. The present inventors discovered that in this way, a polyolefin
solution
having uniform quality can be continuously obtained in a stable manner with a
high
yield.
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..J
Thus, the manufacturing method of a polyolefin solution according to the
present invention, comprises kneadino a polyolefin i-esin with a liquid beina
composed of a solvent, and is characterize(i by that
(1) a continuous kneader having a self-cleatiinb action is used, and
(2) a starving state is maintained in an intertial section of the kneader at a
polyolefin resin feed section, a liquid feed section, and a section in which
the
kneading of the polyolefin resin and the liquid is initially carried out.
In addition, the manufacturing method of a polyolefin solution accordina
to the present invention comprises kneading a polyolefin resin and a liquid
composed of a solvent, and is characterized by that
(1) a continuous kneadei- having a self-cleanino action is used,
(2) at least one liquid feed section is placed downstream of a polyolefin
resin feed
section, and
(3) the internal pressure in at least one section of the kneader between the
polvolefin resin feed section and a liquid feed section located rnost upstream
is set
higher than the internal pressure of' the kneader in the liquid feed section
located
most upstream.
Brief DescriDtion of the Dra.wings
The invention will be better understood with reference to the following
description of a number of prefei-red ernbodirnerits thereof', biven in the
context of
the accompanying drawinos, in which:
Figure 1 is a schematic diagram showing a first arrangement of the
location of a pressure meter in an extruder arld the location of the liquid
feed
section;
Figure 2 is a schematic diaorarn showing ~i second arranaement of the
location of a pressure meter in an extrudet- and the location of the liquid
feed
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4
section;
Figure 3 is a schematic diagram showing a third arrangement of the
location of a presstire meter in an extruder and the location of the liquid
feed
section;
Figure 4 is a schematic dia(yram showin- a fourth arrangement of the
location of a pressure meter in an extruder and the location of the liquid
feed
section;
Fiotire 5 is a schematic diagram showing a fifth arrangement of the
location of a pressw-e meter in an extruder and the iocation of the liquicl
feed
section;
Fi~ure 6 is a schematic diaaram showing a sixth arrangement of the
location of a pressure meter in an extruder and the location of the liquid
feed
section;
Figure 7 is a schematic diagranl showin~ a seventh arran-ement of the
location of a pressure meter in an extruder and the location of the liquid
feed
section;
Fiaure 8 is a schematic dia-ram showin; an eiahth arranaement of the
location of a pressure rneter in an extruder arid the, location of the licauid
feed
section;
Figure 9 is a schematic diagrani showing a ninth arrangement of the
location of a pressure meter in an extruder arid the location of the liquid
feed
section; and
Figure 10 is a schematic dia-ram showinr a tenth arrangement of the
location of a pressure metei- in an extruder and the location of the liquid
feed
section;
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S
In the drawings, the numerals I through 14 indicate a pressure meter, the
numeral
20 indicates an extruder, the nurnei-al 21 indicates n laolyolefin feed
section and the
numeral 22 indicates a licluid feed section.
DETAILED DESCRIPq'ION OF PREFERREI) EMBC>DIIVIENTS
The present invention will be clescribed iti detail hereafter.
(1] Polyolefin resin
The polyolefin resin can be -2 crvstalline homopolymer or copolymer
obtained by polymerizing ethylene, propylene, 1-butene, 4-rnethyl-l-pentene or
1-
hexene or a blend thereof. The copolymer can be, for example, a block
copolymer
(rnulti-step polymer), obtained by introducino propylene and ethyiene
sequentially
to a i-eactor. Amona those above, polypropylene., l)olyethylene and a blend of
them
are preferable. The polyolefin inay be in powder or pellet form.
Among the polyolefin resins, preferi-ed is a polyolefin resin containing a
component with a molecular weight of at least I x 106. Examples of polyolefin
resins containing a component having a rnolecular wei-ht of at least I x 106
include
crystalline homopolyrners and copolymers of ethylene, propylene, 1-butene, ~"T-
nlethyl-l-pentene, 1-hexene and the like and blends thereof. Among them,
preferred is an ultra high molecular weight polyethylene containin; at least
5% by
weight of a component havin~ a molecular wei 2ht oY~ at least i x 10~>.
As for the polyolefin resin described above, it is desirable that it contains
at least 5% by weight (according to the GPC tnethod), moi-e desirably 10% by
weight to 90% by weight, of a component havinc a molecular weight of at least
1 x
106. In addition, it is desirable that the molecular wei;ht distribntion
(weight
avera~e molecular weight/number average molecular weight) of the polyolefir
resin described above, is 5 to 300. Wllen the component having a molecular
wei.ght
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6
of at least I x 106 is less than 5% by weight, the drawing property of a
formed
object made from the solution, cannot be improved, and it is not possible to
obtain a
formed object with sufficient strength. ln addition, i he afore-mentioned
range of
molecular weight distribution is desirable in order to easily prepare the
solution.
Preferred is a polvolefin resin produced bv a reactor blend (multi.-step
polymerized polyolefin), or a mixture of two oi- rnore of such polyolefins.
Foy-
example, a mixture can be made by blending a polyolefin containing at least 5%
by
weight of a component having a molecular wei~;ht of at least I x 106 with a
polvolefin having a molecular weiaht of at least I x1(:34 but less than I x
106. A
mixture prepared by blending the polyethylene liaving an ultra high molecular
weight described above with high density polyethylene having the molecular
weight
described above is especially desirable. For- example, a reactor blend
containing at
least 5% by weight of a component having a molecular weight of at least I x
106
and a molecular weight dish~ibution (weight average molecular weightlnumber
average molecular weight) of 5 to 300 can be produced bv rneans of multi-step
polymerization. As for the multi-step polymerization rnethod, it is desirable
to use a
2-step polymerization method to produce the high rnolecular weight polymer
portion and the low molecular weight polymer portion.
In the manner described above, the polvolefin containing a component
having a molecular weight of at least t~. 14~~,, niore desirably an ultra high
molecular weight polyolefin containinb at least 5% by weight percent of a
component having a molecular weight of at least 1 x 106, especially ultra hibh
molecular weight polyethylene describeci previously, or a mixture of the ultra
high
molecular weight polyethylene anci high density polyethylene, is especially
desirable
as a solution for forminQ rnicroporous niembranes.
It is possible to add various additives, as tieeded, such as nucleation agent,
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anti-oxidant, ultra-violet ray absorbin; aoent, anti-blockin; aoent, pigment,
dye,
inorganic filler, anti-bacterial agent, deodorant, far-infrared radiation
irradiation
agent and the like.
[2] Liquid
The liquid to be added to the polyolefin resin is a low volatile and good
solvent for the polvolefin resin, and is for example, low volatile aliphatic
or cyclic
hydrocarbons such as nonane, decane, decalin, p-xylene, undeeane, dodecane,
liquid
paraffin and the like, or a fraction of mineral oil having a boiling point
corresponding to the above.
As for the mixing ratio of the polyolefin resin and the liquid, the quantity
of the liquid is 15 parts by weight to 2000 parts by weiaht, more desirably 20
parts
by wei~ht to 1500 parts by wei~ht per 100 parts by wei~ht of the laolyolefin
resin.
When the quantity of the liquid goes over 2000 parts by weight, kneading
becomes
difficult. On the other hand, when the quantity of the liquid is less than 15
parts by
weight, the viscosity is hi-h and the quality deteriorates due to shearine,
heat at the
time of kneading.
131 Continuous kneader
The continuous kneader used ior manufacturina the polyolefin solution
has a self-cleaninIg action. In the case of the c.ontinZ ious kneader with the
self-
cleaning action, through aaroove section of 1_ screw, a thread ridqe o:r
another
screw or a protrudin~ section or the like of a cylinder passes, so that the
mixture
does not rotate with the screw, and it is possible to dii-ect the mixture in a
direction
in accordance with the thread ridge of the screw or a combination angle of a
kneading disk. Therefore, in the case that there is a self-cleaning action, it
is
possible to keep a liquid feed section and a section in which the kneadin~ of
the
polvolefin resin and the iiquid is initially carried out in a starving state.
The self-
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cleaninlc, action of the kneader does not have to be effective in all sections
of the
kneader, but it is sufficient that the self-cleanino, action is effective in
at least a
section of the kneader in which the mixture described above exists, so that a
liauid
feed section and the section in which the kneadirrc, of the polyolefin resin
and the
liquid is initially carried out, are kept in the starved state.
In addition, the self-cleanin- action in the kneader cloes not have to be
effective in all section of the kneader, but it is enouah that ttie self-
cleanin- action is
effective in at least one section of the sections in which the mixture
described above
exists, so that the pressure in the licluid feed section is tOko/cm2or below.
A twin-screw kneader or special single screw kneader is preferred as
this type of continuous kneader described above. Specific examples of such
kneader
includes a co-rotating twin screw mixer (extruder), a counter-rotating twin
screw
mixter (extruder), or a special single-screw kneader such as a Bosco kneader
and
the like. The co-ratating twin-screw mixer is especially preferred.
On the other ha.nd, in the case of a kneader without a self-cleaninc, action,
even if a thread rid;e of the screw is in the direction of feedin~, the
coefficient of
friction between a cylinder and the mixture of the polyolefin resin and the
liquid in
which the kneading has not been made sufficient, is extremely low, and the
mixture
described above only rotates with the screw, ~ind it tioes not have the
capacity to
feed the mixture toward the lower strearn. Therefore, in the case of a
Icneader
without self-cleaning action, it is not possible to keep the liquid feed
section and the
section in which the polyolefin resin and the liquid are initially kneaded in
a
starvina state. In addition, in order to move downstream the mixture rotating
with
this screw, an upstream pressure has to be increased. For that reason, the
pressure
is high in the case of the kneader without self-cleaning action.
At least one liquid feed section is placed. at a polyolefin resin feed
sectiori
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or downstream thereof. The liquid is supplied en route to the kneader in which
the
polyolefin resin exists, and the solution of thc polyolefin resin of a uniform
concentration is prepared by kneading.
[4] Kneading conditions
(1) Conditions inside the kneader
The nianufacturing method of a polyolefin solution according to the
present invention, includes a case that a polyolefin i-esin and a liquid are
supplied
from the sanie feed section, and a case that the liquid feed section is placed
downstream of the feed section of the polyolefin resin_ It is necessary to k-
eep an
internal section of the kneader at each feed section in a starvin(y state. In
addition,
it is necessary to keep the internal section of the kneader at a kneading
section of an
initial liquid and the polyolefin resin in a starving state. The starving
state of the
internal section of the kneader here means that there exists an air space
between the
cylinder and the screw where the polyolefin resiri or the mixture of' the
liquid with
the polyolefin resin does not exist. When such a starving state is realized,
the
pressure toward the direction of the screw length becomes 0.
In the manner described above, by making the pressure 0, it is possible to
transport the mixture of the polyolefin resin and the liquid which has not
been yet
well kneaded toward the lower stream, without creating a backflow of the
liquid
even though there is a section where the polyolefin resin is not filled
sufficientl_y
upstrean-i of the liquid feed section. The fact that ttiere is no section
being filled
with only the polyolefin resin, means that the deterioration of the polyolefin
resin
does not take place due to the sheai-ing heat, even though the polyolefin
resin with
high viscosity is used.
In addition, in the case that the liquid feed section is placed at the
polyolefin resin feed section and downstream thereof, it is preferred in the
case that
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an extremely large quantity of the liquid is supplied, to keep at least one
internal
section of the kneader is filled with the polyole.fin resin, between the
polyolefin
resin feed section and the liquid feed section located most upstream. As
described
above, in the case that there is a section filled upstream, it is possible to
reduce a
5 pressure in the section filled with only a polyolefin resin, and it is
possible to
prevent deterioration due to the heat at the section of the polyolefin resin
alone.
This means that upstream from the liquid feed section located the most
upstream in a starving state, a section is created of a greater pressure than
the
internal pressure at the said liquid feed section. A back flow toward upstream
can
10 be prevented, by creating the pressure distribution in the manner described
above,
even when the quantity of the liquid is increased. As a result, an increase in
yield
can be achieved.
In addition, when two or more liquid feed sections are to be placed
downstream of the polyolefin resin feed section, it is preferred for the same
reason to
set the internal pressure of at least one internal section of the kneader
between the
most upstream liquid feed section and the next downstream liquid feed section,
at a
higher value than the internal pressure of the liquid feed section of the
kneader
located most upstream. Furthermore, it is preferred to keep the internal
pressure of
at least one section of the kneader between the liquid feed section most
upstream
and the liquid feed section located next downstream, larger than the internal
pressure in the kneader located in the consecutive two liquid feed sections
immediately downstream of the polyolefin resin feed section. Doing so is
advantageous since the quantity of supplied liquid and the yield can be
increased.
The pressure distribution described above can be obtained by changing
the shape of the screw of the kneader, the liquid feed location, operation
conditions
such as screw rotation number and the like.
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(2) Internal pressure distribution in the kneader
The method of manufacturing a polyolefin solution according to the
present invention can be characterized by that a specific pressure
distribution is
maintained in the kneader. The pressure in the kneader here is an average
value of
the pressure in the internal section of the kneader over a coaistant time
interval, and
this constant time is a sufficiently long tinle to averaoe out the changes in
pressure
attributable a rotation of the screw of the kneader.
To achieve the desired pr-essure distribution, at least one section of the
kneader located between the polyolefin resin feed section and the most
upstream
liquid feed, is kept at a liigher pressure than the pressure of the nlost
upstream
liquid feed. In other words, a section having g:reater pressure than the
internal
pressure of the liquid feed section is maintained upstream of the rnost
upstream
liquid feed. By establishiiig the pressure distribution in the manrrer
described above,
it is possible to prevent a backflow toward the upstreAun side of the kneader,
even
though the quantity of the added liquid is increased, and as a result, the
yield can be
increased.
In addition, when two or more liquid feed sections are to be placed, for
the same reason, it is desirable to set the pressure in at least one section
in the
kneader between each of the liquid feed section and the feed section located
immediately downstream, larger than the inner pressure of the iiqUid feed
section
located irnmediately downstream. Furthermore, it is clesirable to set the
pressure in
at least one section in the kneader between each of the liquid feed section
and the
feed section located immediately downstream, larger than the inner pressure of
the
two liquid feed sections described above. By doing so is an advantage that the
liquid feed quantity and the yield can be increased.
In addition, it is desirable that the pressLu-e in the kneader at the liquid
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76042-6
12
feed section located most upstream is set less than 10 kg/cm2 (gauge
pressure).
Upstream of the most upstream liquid feed section, in order to provide-
shearing to
the section of the polyolefin resin along with high viscosity, the section
filled with
only the polyolefin is reduced to the minimum, by setting the pressure in the
kneader within the range described above, and as a result, the shearing heat
is
controlled and the deterioration due to the heat can be prevented.
The pressure distribution described above can be obtained by changing
the sbape of the screw of the kneader and the like.
(3)Kneading temperature
It is desirable that the kneading temperature be set from the melting point of
the
polyolefin to 250 C, preferably from the melting point of the polyolefin + 10
C-to
220 C. If the kneading temperature is less than the melting point of a
polyolefin-,
sufficient kneading cannot be carried out, and if the kneading temperature is
higher
than 250 C, the deterioration of a polyolefin resin takes place.
Effects
In the present invention, it is possible to make the pressure at the liquid
feed section zero, by creating a starving state in the internal section of the
Imeader
at the polyolefin -resin feed section and the liquid feed section and the
initial
kneading section. As a result, it is possible to obtain a uniform polyolefin
solution
with a high yield, without creating the back flow of the liquid, even though
there is
no section filled with only the polyolefin resin upstream of the liquid feed
section.
In addition, when there is a section filled with the polyolefin resin upstream
of the most upstream liquid feed section, it is possible to reduce the
pressure, and the
deterioration due to the heat can be prevented at the section filled with the
polyolefin resin alone, and at the same time, a large quantity of the liquid
can be
supplied.
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13
In the present invention, it is possible to obtain a uniform polyolefin~
solution with a high yield, by creatitig a specific distribution of the
internal
pressure in the kneader.
Exa es
The present invention will be described further in detail by way of the
following Examples however, the present invention is not lirnited to the
Examples.
Examples 1 through 16
Each of the polyolefin resins and the liquids, were kneaded in the mixing
ratios, shown in Table 1, using a co-rotating twin screw rnixer(extruder), TEX-
54,
(manufactured by The Japan Steel Works, f,td. and the screw diameter = 58 mm,
L/D ratio = 42). In addition, the screw shape of the extruder was selected so
that a
preferred pressure distribution could be obtained. F'ressure tr.eters were
placed at
141ocations in the internal section of the krieader. p'i ;ure I through Figure
5 show
the locations of the pressure meters in the internal section of the extruder
and the
liquid feed positions, and the relation of each Example and the Figures are
shown in
Table 1. However, the distance from the pressure meter i to left end of the
extruder 20 was 236 mm, and the distance between each adjacent pressure meter
was 94.5 mm. The die attached to the extruder, contains a slit having a
thickness of
3 mm, and a width of 104 mm. Table I shows the hotyolefin resin and the liquid
being used, and the quantity of supplied liquid for the polyolefin resin 100
parts by
weight. In addition, the quantity (shown with parts by weight for the
polyolefin of
100 parts by weight) of the liquid suppiied from each of' the liquid feed
holes and
the pressure in the internal section of the extruder and operation conditions
are
shown in Table 2. However, the pressut-e value shown in T able 2 was the value
(kg/cm2, gage pressure) if the atmospheric pressure was set as zero. As shown
in
'I'able 1, an extruder of a different structural type was used for each
Example.
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14
In addition, after the measurement of the nressure in the extruder, the
pressure meters of the polyolefin feed section or the liquid feed section
located
most upstream and the pressure meter located at the place immediately
downstream
were removed, and several grains of the polyolefin resin (PE) pellet were
dropped
into the holes where the pressure rxietei-s had been rernoved. T'he PE pellets
went
into the internal section of the extruder irnmediately. Therefore, it was
clear that
the polyolefin feed section, the liquid feed section beinc, located most
unstream and
the location of the pressure meter located at the irnmediately downstream were
in a
starved state. In addition, the screw located in the space between the
polyolefin
feed section and the location of the first pressure meter locate.d at the
immediate
downstream, or in the space between the liqriid feed sectior- located most
upstream
and the location of the pressure meter located immediately downstream, was the
kneading section to carry out the kneading of the polyolefin resin and the
liquid. In
addition, Examples 6 through 16 show that the pressure value (kg/cm2, gage
pressure) at the location of the pressure meter located immediately upstream
of the
liquid feed section located most upstream, was over zero, so that the internal
section
of the extruder was in the filled state. The polyolefin solution, obtained in
the above
manner, was formed into a sheet of 2 rlim in thickness usitlg the press
forrning die.
The sheet being obtained looked superior in its appearance. In addition, the
sheet
was drawn with a simultaneous two-axis, using a bLitch type rolling mill, and
it
became clear that it was possible to draw in the scale of more than 2 x 2 for
all.
Comparative Examples 1 through 6
Each of the polyolefin resins and the liquids, shown in Table 1, were
kneaded, using the co-rotating twin screw mixer (extruder), TEX-54, the same
as
that of Example 1. In addition, the screw shape of the extruder was selected
so that
the preferred pressure distribution could be obtained. The pressure meters
were
CA 02189868 2002-04-22
placed in the same manner with those of Example i.'T'lle location of the
pressure
meter and the location of the Iiquid feed section are shown in FFiQure 1,
Figure 3,
Figure 4, and Fi~ure 6, and the relation of each Cotnparative Exampie and the
Figures are shown in Table 1.
Table 2 shows the internal pressure of the extruder and the operation
conditions. As shown in Table 2, as for the Cornpa.rative Examples, the value
of
the pressure was over zero at the location of the imtnediately downstream of
the
polyolefin resin feed section, or the liquid feed section located rnost
upstream, and
at the location of the pressure meter irnrnediately downstream, it shows that
the
internal of the extruder was in the filled state, and it was not in a
starvinc, state.
However, the pressure value shown in Table 2, was the value when the
atmospheric
pressure was zero (kglcm2, ga,e pressure). ~l,he operation conditions shown in
Table 2 were the conditions when the stable production could be seen and when
the
maximum yield was realized.
In Comparative Example I throuoh Comparative Example 4, vvhen the
yield was increased, the following phenomena were observed: its variation
became
big and the liquid not being kneaded jets out interniittently.
In addition, the polyolefin solution in Cornparative Example 5 and
Comparative Example 6 was formed into a sheet of 2 ml-rl in thickness, using a
press forminc, die. The color of the sheet was chanQed to yellow.
5ubsequently,
this sheet was drawn with a simultaneous two-axis, using a batch type rolling
mill,
however, it was torri in all experimental coriditions.
16
Table 1
Quantity of Supplied
No. Polyolefin Resin Liquid Liquid "I Types of the Extruder
Examples
1 P E - 1 'Z' Liquid Parafin '8' 3 0 Figure 1
2 P E - 23' ii 3 0 Figure 1
3 P E - 1 ii 5 0 0 Figure 2
4 P E - 2 ii 5 0 0 Figure 2
PE-2 ~i 500 Figure 2
6 P E - 1 ~i 1 5 0 Figure 3
7 P E - 2 ~i 1 5 0 Figure 3
8 P E - 1 ri 5 0 0 Figure 4
9 PE-2 ii 500 Figure 4
PE-1 1 200 Figure 5
11 PE-2 ii 1 2 0 0 Figure 5
12 P E 31 4i n 5 0 0 Figure 5
= 13 P E - 4'5 ii 5 0 0 Figure 5
14 P E - 5"' ~i 5 0 0 Figure 4
p P ") ii 3 0 0 Figure 3
16 p p ir 1 2 0 0 Figure 4 co
Comparative 00
Examples 00
i P E - 1 3 0 Figure 1
2 PE-2 i~ 3 0 Figure 1
3 PE-1 ii 1 50 Figure 6
4 PE-2 ii 1 5 0 Figure 6
5 PE-2 >i 500 Figure :l
6 P P 3 0 0 Figure 3
Note: (1) Quantity of supplied liquid:Parts by weight nf the liquid for the
100 parts by weight of the
polyolefin resin
(Z)PE-l:Weight average molecular weight 3.7X10' powder-form polyethylene(PE)
(3)PE-2:Weight average molecular weight 2.OX106 powder-form
polyethylene(PE)and Weight average
molecular weight 3.7X10' powder-form polyethylene(PE)were blended using 3:14
ratio.(Component of the
molecular weight of 1X10' and over according to the GPC method, 21.6% bv
weight percent)
(4)PE-3:Weight average molecular weight 3.7X105 pellet-form PE.
(5)PE 4:Weight average molecular weight 2.0X10' powder-form
polyethylene(PE)and Weight average
molecular weight 3.7X105 pellet-form polyethylene(PE),are blended using 3:14
ratio.(Component of the
molecular weight of 1X10' and over according to the GPC method,21.6% by
weight)
(6)PE-5:Weight average molecular weight 2X106 powder-form polyethylene
(7)PP:Weight average molecular weight 3.9X10' pellet-form polypropylene,to
which sorbitol-based
nucleation agent was added by lpart by weight.
(8)Liquid paraffin:Kinematic viscosity at 40'C is 64 cSt.
17
Table 2 Feed Quantity of the Liquid, Internal Pressure in the Extruder, and
the Operation Conditions
Position on the Extruder Cylinder Screw Rotation
! -r- Yield
Polyolefin Tenm. Number
Resin 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Feed Hole 'C rpm kg/h
Example Liquid Feed Quantity 30 - - - - - - - - - - - - - 150 100 80
1 Pressure in the Internal of the Extruder - 0.0 0.0 0. 0 0.0 0. 0 0.0 0.0 0.0
0.0 0.0 0.0 0.0 0.0 0.0 ~ 200
30 150 100 40
Ex2~lG PrLiquid essuree~ Quantity of the Extruder
- 0.0 0. 0 0. 0 0.0 0.0 0.0 0. 0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 -200
j----- -~ -~- -~ ------ -
Example Liquid Feed Quantity _ 80 - - 180 - 240 - - - - - - - r 150 350 90
3 Pressure in the Internal of the Extruder 0. 0 0. 0 0. 0 0. 0 0,0 0. 0 0. 0
0. 0 0. 0 0. 0 0. 0 0. 0 0. 0 0. 0 ~ 200
Example Liquid Feed Quantity - 50 -;- 180 - 1 270 - -- - - - 150 350 100
= 4 Pressure in the Internal of the Extruder - ( 0.0 0. 0 1 2. 6 1.4 1.0 8.9
7.8 7.8 6. 0 5.1 4.0 2.1 0.2 0.0 ~-200
Example Liquid Feed Quantity - 80 - - 180 - - 240 - - - - - - -' 150 350 60
Fressure in the Internal of the Extruder - 0.0 0. 0 0.0 0.0 0.0 j 0. 0 0 ~ 0
0.0 0.0 0. 0 0. 0 0.0 0. 0 0.0 -200 Example Liquid Feed Quantity
~~-
- - -! 150 - - ji--~j -- - - - 150 200 200 rv
6 Pressure in the Internal ef the Extruder 0. 0 Z. 1 0. 0 0. 0 U 0 l 0.0 0.0
0. U u. U 0. 0 1 0. 0 0. 0 0. 0 -200 00
Fxample Liquid Feed Quantity - - - 150 - - - - - - - - -- - 150 200 100
7 Pressure in the Internal of the Extruder - 0. 0 i. 4 0, 0 0. 0 O. 0 0, 0 0,
0 0. 0 0- 0 0. 0 0. 0 0, D 0. 0 ~200
O1
0.0 t---- ;------ _
Examrle Liquid Feed Quantity - - -; 130 370 350 200
8 Pressure in the Internal of the Extruder 0.0 .9 0. 0; 0 0 0 0i0. i i~' 9. 6
8.6 4 a% o. 1 -200
3. 6 0.8
-~
~---~-
Example Liquid Feed Quantity - - - 130 T- -! 370 - - - -!- ~- I - 15~ 350 100
o
9 Pressure in the Internal of the Extruder 0.9 0 0 0.0 11.2 10.2 9.8 9 5 8.2
7.4 6. 0 4.6 3. 6 1.8 ~-200
-- - - - - --- -- - -~
780 i- - - - 150 6po 200 N
4-~-
p iluantity 140 - -'-- 280 ,
Pressure in the Internal of the Extruder 0.0 0.0 0,0 0.0 2.2 0.9 0.7 20.1
~arrt~le iquid r
1! 15.315.0 14.211~.48.0 3.i 200 (.
, - -
Example Liquid Feed Quantity - - 140 - - 280 780 - - - - 150 600 100
11 Pressure in the Internal of the Extruder - 0. 0 0.4 U. 0 0. 0 2 . 4 l . 1
U. 8 1 1 . 5 10.2 10. 0 8.9 3. 0 0. 200
---~-------- ~--~--
- - 100 Liquid Feed Quantity - - 200 - - 200 - - - - 'rJ 150 l~n
~ample ~ 1J f J~
12 Pressure in the Internal of the Extruder - 0.0 2 . 6 6.0 0.0 5. 3 2. 6 0.7
15- 3 10.2 10.0 9.5 8. 1 4.9 2.9 200
Fxarttple Liquid Feed Quantity - - 80 -- 180 - - 240 - - 150
350
13 Pressure in the Internal of the Extruder - 0. 0 1.4 0. 0 0. 0 2. 6 1. 8 0.7
5. 5 4.4 4. 3 4. 2 4. 0 3.6 2.9 200 ( 80
Fatample Liquid Feed Quantity _ - - 130 - - 370 - - - - - - - - 150 250 50
14 Pressure in the Internal of the Extruder 0.0 0.2 0.0 0.0 1. 1 0. 5 0. 3 0.2
0.1 0.0 0.0 0.0 0.0 0.0 ~-200
Example Liquid Feed Quantity - - - 300 - - - - - - - - - 150 150 200
Pressure in the Internal of the Extruder - 0. 0 1.4 0.0 0.0 0. 0 0.0 0.0 0.0
0.0 0.0 0,0 14.0 13.6 12.9 ~-200
Example Liquid Feed Quantity - - - 230 - - !970 - - - - - - - - 150 600 200
6 Pressure in the Internal of the Extruder - 0.0 1.0 0.0 0.0 3.9 2. 3 2. 1 1.2
0.8 1. 3 9.8 5.6 4.3 3.1 ~-200
18
Table 2-2 Feed Quantity of the Liquid, Internal Pressure in the Fxtruder, and
the Operation Conditions
Position on the Extruder Cylinder Screw Rotation
Yield
Polyolefin Temp. Nwnber
Resin 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Feed Hole C rpm kg/h
Comparative Liquid Feed Quantity 30 - - - - - - - - - - - - - - 150 100 4
Example 1 Pressure in the Internal of the Extruder - 6.8 6. 3 5. 3 4.9 3.3 2.5
0. 6 0.0 0.0 0.0 0.0 0.0 0.0 0. 0 -~200
Comparative Liquid Feed Quantity 30 - - - - - - - - - - - - - - 150 100 2
Example 2 Pressure in the Internal of the Fxtruder - 1.1 4. 5 8. 6 4.8 2.9 1.4
0.0 0. 0 0.0 0.0 0.0 0.0 0.0 0. 0 -200
Comparative Liquid Feed Quantit - 30 - - 0 - 45 - - 150 200 10
Exarnple 3 Pressure in the Internal of the Ext-ruder - 0.0 0.4 4.3 5.6 1.1 3
18. 10.6 6 1 167 17.5 1.5 0.7 34.3 29.7 ~-200
Gcmpa~at.ivz Liquid Feed Quantit.y 30 35 40~ 45 150 200 8
Ex.atr~ple 4 Pressure in the Internal of the Extruder 0. 0 1 0.0 2.4 4.1 0. 0
10. 3 15. 2 0. 4 13.2 14.1 0.2 2,.). 5 30.1 25.1 200
-----
Comparative Liquid Feed Quantity - - - 130 - - 370 - - - - - - - - 150 350 100
Example 5 Pressure in the Internal of the Ext.ruder i.! II 11. 2 8. 5 40.6
31.2 30.1 25. 3 23. 5 20.1 16.7 13.1 10.1 6.7 ~-200
= -- r - ----- - I -
Comparative L.tquid Feed Quantity 300 - - - - - - - - I - - - 150 150 200 N
Example 6 Pressure in the Internal of the Extruder - ) 6. 5 32.5 12.5 11. 3
9.9 8 5 1 7.3 b. 0 4.1 2.3 0. 8 j 5. 2 15.3 10. 3 -200 00
00
rn
00
CA 02189868 2002-04-22
19
Examples 17 through 33
Each of the polyolefin resins and the 11quids, shown in "' able 3, were
kneaded, usin; the co-rotatinb twin screw niixer(extruder),TEX-54,
(manufactured
by 'The Japan Steel Works Ltd., anci the screzx., diameter = 58 mm, L/D ratio
= 42).
In addition, the screw shape of the extruder was selected so that a preferred
pressure distribution could be obtained. The pressure ineters were placed at
14
locations of the internal section of the kneader. 1-'ioure 7 through Figure 10
show
the locations of the pressure meters in the internal section of the extruder
and the
liquid feed positions, and the relation of each Exatnple and the F'iQures are
shown in
Table 4 and 6. However, the distance frotn the pressure meter 1 to left end of
the
extruder 20 was 142 mm, and the distance between each pressure meter adjoining
was 94.5 mm.
Table 4 and Table 6 show the operation conditions, and Table 5 and Table
7 show the pressure distribution being measured. However, the pressure values
shown in Table 5 and Table 7 were the value (gauge pressure) at the time when
the
atmospheric pressure was set as zero. 1'he oDeration conditions shown in
'hable 4
and Table 6 were the conditions at the tirne of maximum yield when a stable
yield
was seen.
The polyolefin solution obtained in the above manner, is formed into a
sheet of 2 mm in thickness using a p1-ess forming die. The sheet obtained
looked
superior in its appearance. In addition, the sheet was dt-awn irt simultaneous
two-
axis, using a batch type rolling mill, and it was clear that it was possible
to draw in
the scale of more than 2 x 2 for all.
Comparative Example 7 through Comparative Example 12
Each of the polyolefin resins and the liquids, shown in Table 3, were
CA 02189868 2002-04-22
kneaded, usina co-rotating twin screw mixer (extruder), TEX--54, the same with
Example 17. In addition, the screw shape of the extruder was selected so that
a
preferred pressure distribution could be obtained. The pressure meters were
placed in the same manner with that of Example 17. "i,he locations of the
pressure
meters and the locations of the liquid feed sections are shown in Fioure 7
through
Figure 10, and the relation of each Comparative, Example and the Figures are
shown in Table 4 and Table 6.
Table 4 and Table 6 show the operation conditions, and Table 5 and Table
7 show the pressure distribution being rneastired. However, the operation
conditions were the conditions at the time of maximum yield when the stable
yield
was observed.
In Comparative Examples 7, 8, 10 and 1 i, when the yield was increased,
the following phenomena were observed: its variation becomes big and the
liquid
not being kneaded jetted out interrnittently.
in addition, the polyolefin solutions in the Comparative Example 9 and
the Comparative Example 12 were formed i.nto a sheet of 2 mm in thickness,
usin~
a press forming die, and these sheets were drawn in simultaneous two-axis,
rising
the batch type rolling mill, however, these sheets were torn in all
experimental
conditions.
21
Table 3
Quantity of Supplied
No. Polyolefin Resin Liquid Liguid'1'
Examples
17 P E- 1'2 ' Liquid Parafin'$' 5 0 0
18 PE-l 500
19 PE-1 30
20 PE-1 ~i 1 50
21 PE-1 500
22 PE-1 1 2 0 0
2 3 P E- 3'A' 5 0 0
24 PP "' 300
25 PP 1 200 0
26 PE-2 500
27 PE-2 500
28 PE-2 30 00
29 PE-2 1 50 00
30 PE-2 500 D
3 1 P P - 2 1 2 00
32 PE-4 cs ,~ 5 0 0
33 PE-5 500
Comparative Examples
7 P E- 1 3 0
8 PE-1 i~ 150
= 9 PP '1 50
P E- 2 3 0
lI P E 2 " 1 5 0
12 PE-2 ~i 500
Note :(I)through(8) are the same as those of the Table 1.
22
Table 4 Feed Quantity of Liquid"" and the Operation Conditions of the Kneader
---
Position on the Kneader 121 Cylinder Screw Rotation
Yield
Temp. Number
1 2 3 4 5 6 7 8 9 10 11 12 13 14
C rpm kg/h
_ __----
----
_- ---- -- - -
Example 17 - - 220 - - J 140 - - J 140 - - J- J- - 150 ~-200 200 80
Example 18 - - 160 - - 170 - - 170 - - - - - 150 ~-200 350 100
I Example 19 - - 30 - ~ - - - - - - - - - - 1150 ~-200 100 100
---- , Example 20 - - 150 150 ~-200
200 200
- - { - _ _-
~ '~0 370 _ - - - - - - 150 ~-200 350 200
Example ..l - - 1 õ , - -
--- - -- - !
Example 22 - - 140 ,- -~ 280 -;- 780 - - - - - 150 ~~200 600 200
{ ao
_- ! ~
Example 23 - - 60~ - - 130 -~- 310 - I-~-- J- - 150 ~-200 350 160
0,
300 150 ~-200 150 200 D
Exam le 24
P
- -i--'------- N
--~ - T , , rt
Example 25 J - 230 - ! - 970 ! - - - ~ - - - ! - - 15 0 0 ~-20 600 200
- -- - _ __ __ -- ---
_ - _ ~- - '-- j
Comparative Example 7 - - 30 150 -200 100
- , ,
Comparative Example 8 30 40 ~- - 45 150 -200 200 10
~ 200
Comparative Exampie 3 ~0 JJI 4r,
4,i 150 ~00 i3
-
---- _ -_ -- -----'------ - ----- ~-_ Note:
(1) Feed quantity of liquid: Parts by weight of the liquid for the polyolefin
resin 100 parts by weight.
(2) Position in the Kneader: The numericals 1 through 14 indicate the location
positions of pressure
meters shown in Figure 7 through Figure 10.
23
Table 5 Internal Pressure in the Kneader (kg/cm2)
Position on the Kneader "'
1 2 3 4 5 6 7 8 9 10 11 12 13 14
Example 17 0. 0 15. 2 10. 1 8. 6 2. 1 0. 0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Example 18 0. 0 5. 1 0. 0 0.0 0. 0-~~ 0. 0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
Example 19 0.0 19.315.311.2 6 7.2 4.0 1.8 0.0 0.0 0.0 0.0 0.0 0.0
Example 20 0.0 10.9 8.6 8.4 8.2 8.0 7.51 6.7 5.2 3.9 2.41 0.8 0.0~ 0.0
Example 21 0.0 9. 1 4.8 2.2 20.1 15.4 15.0 14.2 13.5 12.1 11. 1 9.8 8.4 7.2
Example22 0.0 0.8 0.0 0.0 9.5 5.3 4.211 25.218.318.017.617.1 16.6 15.9
ao
Example 23 0. 0 10. 3 6.3 2.425.61 20.3I 5.626.519.6 18.517.316.4115.012.4
--- _ 4 -j -i- _
5.9 --~ 5. 5, 5.0 4.6 4.0 3.2 1.6 0. 2 D
Example 24 G. G 9. 4 6.8 6.8 6. 5 6. 3 - -~~ o
Example2) 0.Or 3 1. 1 0.0113.39.3i 9.3 9.3; 9.2~ 9.29.0~ 7.8 6.8;
0.0 ~ 0.0 0.0 0.0 0.0 0.0 0.0
Comparative Example 7 0. 0 2. 5 8 21 11. 1 7 . 2 4 2 0 9
_
~~~omparati~,e ExamPlP n U. U 0. 4 4, i h, h 1 . 1 17 i lts. 1 U.h 1 6 . 7
17.5 1 . ~ 30.7 34, s 1 29. 71
--a- --I-
Comparative Example 9 0. 0 0. 0 3 . 1 4_ 3 3 10. 5 1 2 . 2 3. 1 2 . 3 14. ? G
~ ! 25. 3 28. ! 24. 3
Note:
(1) Position in the kneader: The nLmericals 1 throug.h 14 indicate location
positions of press.:re
meters shown in Figure 7 through Figure 10.
24
Table 6 Feed Quantity of Liquidand the Operation Conditions of the Kneader
Position on the Kneader Cylinder Screw Rotation
- - -- ---
Temp. Number Yield
1 2 3 4 5 6 7 8 9 10 11 12 13 14 rpm kglh
-- - - - --- - -
Example 26 - - 220 - ! - 140I - - 140 - - - ! - - 150 ~-200 200 50
; -_- _-- - f - ---__ i ~----- -----~ - -- ----- - -- -
LExample 27 - - 160 - - 170 - - 170 - - - -~- 150 ~-200 350 70
70 Example 28 30 15
~- - - - - -~- - 0 ~-200 100
Example 29 150 - + - - - - 150 ~-200 200 100
~--- - - -- -------~- i ~--r-~ 17 -1---~---~ --- 350
1--1
Example 30 -!- 130 - - 0 - - - - - - - - 150 -200 35u 100
-------------- - - +--- { - - , _
'
Example 31 2
- ~ 140 - T fiQ~ r80 T- 150 - 20G 600 100 oo
, - -- - - - ---- , -T--- ~
Example 32 - - 60 -~-~ 130 (- - 310 -~- - - - 150 -200 350 80
_---- -- - ~--~ 00
_ -' o
- j- 150 ~ 200 250 50 o
--- -- _ - _ ~
1 _ ------- -- ---
Go parative Example 101 - - 1~~ -~ - ~70 - -~- - - - - -;150 -200 100 3 N
--- - -_i - - - _ = 1--- - { o
-- ---- ---! ---! ---, _ ~ _ ---' - -
i ~----- -- .-.-----' Ip
Comparative Example 11 ! - 30 30 40 50 - 1 150 -200 200 8
-- -- -
rt- ?
Comparative Example 121 - 130 - 1 370 150 -200 350 100
- -- -~ - ! - - ~ -~
Note:
(1) Feed quantity of liquid: Parts by weight of the liquid for the polyolefin
resin 100 parts by weight.
(2) Position in the Kneader: The numericals 1 through 14 indicate the location
positions of pressure
meters shown in Figure 7 through Figure 10.
25
Table 7 Internal Pressure in the Kneader (kglcm2)
Position on the Kneader
1 2 3 4 5 6 7 8 9 10 11 12 13 14
--- - - - -
Example 26 0.0 2.8 2.0 0.8 0. 0 0. 0 0.0 0 0 0.0 0.0 0.0 0.0 0.0 0.0
---_ - -_._ __---- ---- -- _--~ { -i
Example 27 0. 0 1.4 0.0 0.0 0.0 0.0 0.0 0.0
2. 0.0 0.0 L ~0.0 0.0 0.0 0 - .0~~
__ T - -----~ - ~-_
Example28 0.0 I 9 2.4i u.0 0.0i 0.0 0.01 0.0 0.0 0.0 0.0 0.0 0.0 0.0
___ _ --- ~_----- - _~_--- __ -- - , ,
Example 29 0. 0 1 . 5 0. 5 0. 0 0. 0 0. 0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0
- --~
~ Example 30 0.0 l . 3 0.4 0.0 1 1 : 2 10 1 9. 8 1 11.4 9. : i 8. 1 ~: 3 5.9
~. 3.44 _~
Lxample3l 0. 0 0. 4 0 0 u.~0 5 iL; ~.~10.1 9 8.6 0.93.1 ~.3 00
Example32 0.0I 1.3i 0.2 0.01 2.5 1.81 0.7 5.5 4.5 4.4 4.3 4.1 3.6 3.0
Example 33 0.0 0.3 0.0 0.0 1.3 0.61 0.51 0.3 0Ø0 0.0 0.01 0.0 O.Oi
Comparative Example 10 0. 0 2.3 !. 5 i 10. 5 5. 7 1 2. 2' 0 c
~ " - - ~;--' ~,-~ 0.0 0.0 0.0 0.0 0.0 0.0 0.0
o
Comparat~:eExample~l, 0.0; 0.01 ~..4 4.11 0.01Q V ~15.2 0.4 13.2 14.11
0.2~22.530.11 25.1~
Comparative Example 1 2 1. 7 1 15. 2 11,2 8. 5 40. 6 31. 2 30.1 25.3 23.5 1
20. 1 I 16. 7 13.1 10.1 1 6.7
rote :
(1) Position in the kneader: The numericals 1 through 14 indicate location
positions of pressure
meters shown in Figure 7 through Figure 10.
CA 02189868 2002-04-22
26
Applicability in Industry-
As described in detail above, with a riiethod accordiria to the present
invention, by creating a straving state in an inter-nai section of the kneader
at a
polyolefin resin feed section and a licluid feed section, and an initial
lcneadinc,
section, it is possible to obtain a uniform polyolefin solution with a high
yield,
without creatinb a backflow of the liyuid. The polyolefin solution obtained by
a
method according to the present invention in the rnanner described above, can
be
used for manufacturing various types of polyolefin fornied objects.
In addition, a rnanufacturinb method acc.orclin- to the present invention
can prevent a backflow of a liquid, and catl contirruously obtain a high yield
of a
uniform polyolefin solution, by means of a specific distribution of a pressure
in the
kneader. The polyolefin solution obtained by .: rnethod according to the
present
invention in the nianner described above, can be used for manufacturing
various
types of polyolefin formed objects, and is especially suitable for forming
microporous mernbranes.
