U.S. patent application number 10/242463 was filed with the patent office on 2003-06-19 for thermoplastic elastomer composition and ethylene-alpha-olefin copolymer.
This patent application is currently assigned to Sumitomo Chemical Company, Limited. Invention is credited to Inagaki, Katsunari, Nishiyama, Tadaaki.
Application Number | 20030114596 10/242463 |
Document ID | / |
Family ID | 27331408 |
Filed Date | 2003-06-19 |
United States Patent
Application |
20030114596 |
Kind Code |
A1 |
Inagaki, Katsunari ; et
al. |
June 19, 2003 |
Thermoplastic elastomer composition and ethylene-alpha-olefin
copolymer
Abstract
A thermoplastic elastomer composition comprising 5 to 95 wt % of
the following (A) and 5 to 95 wt % of the following (B), wherein
the flowability index I according to a test for flow properties
with a capillary rheometer is 1.35 or more: (A) an
ethylene-.alpha.-olefin copolymer having a tensile stress M.sub.100
measured according to JIS-K-6251 of 2.5 MPa or less, (B) a
polyolefin-based resin having a tensile stress M.sub.100 measured
according to JIS-K-6251 of 2.5 MPa or more.
Inventors: |
Inagaki, Katsunari;
(Ichihara-shi, JP) ; Nishiyama, Tadaaki;
(Ichihara-shi, JP) |
Correspondence
Address: |
FITCH EVEN TABIN AND FLANNERY
120 SOUTH LA SALLE STREET
SUITE 1600
CHICAGO
IL
60603-3406
US
|
Assignee: |
Sumitomo Chemical Company,
Limited
|
Family ID: |
27331408 |
Appl. No.: |
10/242463 |
Filed: |
September 13, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10242463 |
Sep 13, 2002 |
|
|
|
09636651 |
Aug 9, 2000 |
|
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Current U.S.
Class: |
525/240 ;
526/348.2; 526/351; 526/352 |
Current CPC
Class: |
C09K 3/10 20130101; C08L
23/0815 20130101; C08L 23/02 20130101; C09K 2200/062 20130101; C08L
23/0815 20130101; C09K 2200/0617 20130101; C08L 23/04 20130101;
C08L 23/0869 20130101; C08L 23/0853 20130101; C08L 2666/04
20130101; C08L 2666/04 20130101; C08L 2666/04 20130101; C09K
2200/0622 20130101; C08L 23/04 20130101; C09K 2200/0625 20130101;
C08L 23/08 20130101; C08L 23/02 20130101; C08L 23/0853 20130101;
C08L 23/08 20130101; C08L 23/0869 20130101; C08L 23/0815
20130101 |
Class at
Publication: |
525/240 ;
526/348.2; 526/351; 526/352 |
International
Class: |
C08F 210/14; C08L
023/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 12, 1999 |
JP |
11-228476 |
Sep 2, 1999 |
JP |
11-248608 |
Nov 16, 1999 |
JP |
11-325132 |
Claims
What is claimed is:
1. A thermoplastic elastomer composition comprising 5 to 95 wt % of
the following (A) and 5 to 95 wt % of the following (B), wherein
the flowability index I according to a test for flow properties
with a capillary rheometer is 1.35 or more: (A) an
ethylene-.alpha.-olefin copolymer having a tensile stress M.sub.100
measured according to JIS-K-6251 of 2.5 MPa or less, (B) a
polyolefin-based resin having a tensile stress M.sub.100 measured
according to JIS-K-6251 of 2.5 MPa or more.
2. The thermoplastic elastomer composition according to claim 1,
wherein (A) is an ethylene-.alpha.-olefin copolymer satisfying the
following conditions (a) to (c): (a) .alpha.-olefin content is from
5 to 95 wt %, (b) Mooney viscosity: ML.sub.1+4100.degree. C. is
from 5 to 70, (c) Q value (weight-average molecular chain
length/number-average molecular chain length) according to GPC
measurement is 4 or more.
3. The thermoplastic elastomer composition according to claim 2,
wherein (A) satisfies the conditions (a) to (c) and the following
condition (d): (d) a molecular weight distribution curve is
bimodal.
4. The thermoplastic elastomer composition according to claim 3,
wherein (A) satisfies the conditions (a) to (d) and the following
conditions (e) to (g): (e) a ratio (H=X1/X2) of high molecular
weight peak height X1 to low molecular weight peak height X2 in a
molecular weight distribution curve is from 2.0 to 7.0, (f) an area
of low molecular weight parts having chain lengths of 100 .ANG. or
less in a molecular weight distribution curve is 3% or less, (g)
heat of fusion of a crystal at temperature of from 50 to
100.degree. C. is 5 mJ/mg or more when measured by a differential
scanning calorimeter (DSC).
5. The thermoplastic elastomer composition according to claim 4,
wherein (A) has an .alpha.-olefin content of from 20 to 40 wt % and
has a Mooney viscosity: ML.sub.1+4100.degree. C. of from 15 to
70.
6. An extrusion molded article obtained by extrusion molding the
thermoplastic elastomer composition according to claim 1.
7. A hose obtained from the molded article according to claim
6.
8. A tube obtained from the molded article according to claim
6.
9. A gasket obtained from the molded article according to claim
6.
10. A packing obtained from the molded article according to claim
6.
11. A calender molded article obtained by calender molding the
thermoplastic elastomer composition according to claim 1.
12. An ethylene-.alpha.-olefin copolymer which comprises ethylene
and an .alpha.-olefin having 3 to 8 carbon atoms, wherein the
copolymer has an .alpha.-olefin content of from 20 to 40 wt %, has
a Mooney viscosity: ML.sub.1+4100.degree. C. of from 15 to 70, and
satisfies the conditions (c) to (g) according to claim 4.
13. The ethylene-.alpha.-olefin copolymer according to claim 12,
wherein the .alpha.-olefin content is from 25 to 40 wt %.
14. A pellet made of the ethylene-.alpha.-olefin copolymer
according to claim 12.
15. An extrusion molded article obtained by extrusion molding of
the ethylene-.alpha.-olefin copolymer according to claim 12.
16. A hose obtained from the molded article according to claim
15.
17. A tube obtained from the molded article according to claim
15.
18. A gasket obtained from the molded article according to claim
15.
19. A packing obtained from the molded article according to claim
15.
20. A calender molded article obtained by calender molding the
thermoplastic elastomer composition according to claim 12.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a thermoplastic elastomer
composition, a molded article obtained by using the thermoplastic
elastomer composition and an ethylene-.alpha.-olefin copolymer.
More specifically, the present invention relates to a thermoplastic
elastomer composition which has excellent flexibility and
processability, manifests no bleed of low molecular weight
components, and particularly excellent in extrusion processability
and calender processability, an extrusion molded article obtained
by extrusion molding the thermoplastic elastomer composition or a
calender molded article obtained by calender molding the
thermoplastic elastomer composition, and an ethylene-.alpha.-olefin
copolymer.
[0003] 2. Description of Related Art
[0004] Soft vinyl chloride materials having good balance between
mechanical strength and flexibility are a material excellent in
processability and cost performance. However, the use thereof is
restricted due to recent environmental problems. On the other hand,
an ethylene-.alpha.-olefin copolymer rubber can be listed as the
polyolefin-based material excellent in recycling property. The
ethylene-.alpha.-olefin copolymer rubber is used widely as an
automobile material, construction material, wire material and
polyolefin-modifying material, together with
ethylene-.alpha.-olefin-non-conjugated diene rubber such as EPDM
and the like. In these uses, excellent processability, particularly
excellent roll processability and excellent extrusion
processability are required in addition to excellent vulcanization
property. From this standpoint, an ethylene-.alpha.-olefin--
non-conjugated diene rubber such as EPDM and the like having
excellent processability by inclusion of a diene component is used
more widely than ethylene-.alpha.-olefin copolymer rubber. As the
conventional technology for further improving processability, there
is a method in which ethylene-.alpha.-olefin-non-conjugated diene
rubber having wider molecular weight distribution is produced by
using a special catalyst such as a vanadate of secondary alcohol
and the like as disclosed, for example, in Japanese Patent
Application Laid-Open (JP-A) No. 61-4708. Further, Japanese Patent
Application Publication (JP-B) No. 6-18942 discloses a rubber
composition obtained by compounding a vulcanized rubber compounding
agent into ethylene-.alpha.-olefin-non-conjugated diene copolymer
rubber having wide molecular weight distribution. The rubber
containing a diene component has excellent processability, but may
cause a problem of remaining of odor in the final product since
this rubber contains a diene monomer odor as compared with rubber
containing no diene component.
[0005] Further, JP-A No. 9-241325 discloses an
ethylene-.alpha.-olefin copolymer rubber which has excellent
processability, heat-resistance and high tensile strength, causes
no bleed in low molecular weight parts, and has a specific
composition, molecular weight and molecular weight distribution.
However, in view of recent further strict quality requirements,
this method include problems that prevention of bleed is
insufficient, the surface appearance of the final product using the
above-mentioned copolymer is degraded, further, pellets of the
copolymer adhere each other under a slight load and small block
form can not be maintained for a long period of time, workability
and handling such as transportation and measurement in compounding
into a polyolefin-based resin are insufficient.
SUMMARY OF THE INVENTION
[0006] The present inventors have intensively studied a
thermoplastic elastomer composition having no above-mentioned
problems, and found that a thermoplastic elastomer composition
comprising a specific ethylene-.alpha.-olefin copolymer and a
specific polyolefin-based resin is excellent in extrusion
processability and calender processability, and gives excellent
flexibility and processability, and manifests no bleed of low
molecular weight components when made into an extrusion molded
article or calender-molded article, and have completed the present
invention.
[0007] Namely, the present invention relates to a thermoplastic
elastomer composition comprising 5 to 95 wt % of the following (A)
and 5 to 95 wt % of the following (B), wherein the flowability
index I according to a test for flow properties with a capillary
rheometer is 1.35 or more:
[0008] (A) an ethylene-.alpha.-olefin copolymer having a tensile
stress M.sub.100 measured according to JIS-K-6251 of 2.5 MPa or
less,
[0009] (B) a polyolefin-based resin having a tensile stress
M.sub.100 measured according to JIS-K-6251 of 2.5 MPa or more.
BRIEF EXPLANATION OF THE DRAWING
[0010] FIG. 1 is a plot diagram of a ratio of shear viscosity
versus shear viscosity in calculating flowability index.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] The present invention will be described below.
[0012] The present invention relates to a thermoplastic elastomer
composition comprising 5 to 95 wt % of the following (A) and 5 to
95 wt % of the following (B), wherein the flowability index I
according to a test for flow properties with a capillary rheometer
is 1.35 or more:
[0013] (A) an ethylene-.alpha.-olefin copolymer having a tensile
stress M.sub.100 measured according to JIS-K-6251 of 2.5 MPa or
less,
[0014] (B) a polyolefin-based resin having a tensile stress
M.sub.100 measured according to JIS-K-6251 of 2.5 MPa or more.
[0015] The component (A) in the present invention is an
ethylene-.alpha.-olefin copolymer having a tensile stress M.sub.100
measured according to JIS-K-6251 of 2.5 MPa or less. The component
(A) should has a tensile stress M.sub.100 measured according to
JIS-K-6251 of 2.5 MPa or less, preferably of 2.0 MPa or less. When
this value is excess, a molded article obtained by molding the
resulting thermoplastic elastomer composition is poor in
flexibility.
[0016] The component (A) is preferably an ethylene-.alpha.-olefin
copolymer satisfying the following conditions (a) to (c), more
preferably an ethylene-.alpha.-olefin copolymer additionally
satisfying the following condition (d), further preferably an
ethylene-.alpha.-olefin copolymer further additionally satisfying
the following conditions (e) to (g).
[0017] (a) .alpha.-olefin content is from 5 to 95 wt %,
[0018] (b) Mooney viscosity: ML.sub.1+4100.degree. C. is from 5 to
70,
[0019] (c) Q value (weight-average molecular chain
length/number-average molecular chain length) in GPC measurement is
4 or more,
[0020] (d) a molecular weight distribution curve is bimodal,
[0021] (e) a ratio (H=X1/X2) of high molecular weight peak height
X1 to low molecular weight peak height X2 in a molecular weight
distribution curve is from 2.0 to 7.0,
[0022] (f) an area of low molecular weight parts having chain
lengths of 100 .ANG. or less in a molecular weight distribution
curve is 3% or less,
[0023] (g) heat of fusion of a crystal at temperature of from 50 to
100.degree. C. is 5 mJ/mg or more when measured by a differential
scanning calorimeter (DSC).
[0024] Specific examples of the .alpha.-olefin in the component (A)
include propylene, 1-butene, 3-methyl-1-butene, 4-methyl-1-pentene,
1-hexene, 1-octene, 1-decene, 1-dodecene, 1-hexadecene, 1-eicosene
and the like. Among them, an .alpha.-olefin having 3 to 8 carbon
atoms is preferable. When the carbon number of the .alpha.-olefin
is 9 or more, the monomer cost of the .alpha.-olefin becomes high,
and may induce disadvantage from the viewpoint of industrial
production. These .alpha.-olefins may be used alone or in
combination thereof. The .alpha.-olefin content in the copolymer of
the present invention is preferably from 5 to 95 wt %, more
preferably from 20 to 90 wt %, further preferably from 20 to 40 wt
%, most preferably from 25 to 40 wt %. When the .alpha.-olefin
content is too low, bleed may occur on the surface of a molded
article obtained by molding the resulting thermoplastic elastomer
composition. On the other hand, when the .alpha.-olefin content is
too high, a molded article obtained by molding the resulting
thermoplastic elastomer composition may be poor in strength.
[0025] The Mooney viscosity: ML.sub.1+4100.degree. C. of the
component (A) is preferably from 5 to 70, more preferably from 15
to 70, and further preferably from 20 to 60. When the Mooney
viscosity is too low, a molded article obtained by molding the
resulting thermoplastic elastomer composition may be poor in
strength. On the other hand, when the Mooney viscosity is too high,
a molded article obtained by molding the resulting thermoplastic
elastomer composition may has deteriorated extrusion
processability.
[0026] The Q value (weight-average molecular chain
length/number-average molecular chain length) in GPC measurement of
the component (A) is preferably 4 or more, more preferably 6 or
more. When the Q value is too low, a molded article obtained by
molding the resulting thermoplastic elastomer composition may has
deteriorated extrusion processability and calender processability.
Higher Q value is preferable from the standpoints of extrusion
processability and calender processability, providing the
constitution conditions of the present invention are satisfied.
Measurement of the Q value is conducted by a gel permeation
chromatography (GPC) method (for example, 150C/GPC apparatus,
manufactured by Waters Co.). The elution temperature is 140.degree.
C., the column used is, for example, Shodex Packed Column A-80M
manufactured by Showa Denko K.K., and as the molecular weight
reference material, polystyrene (for example, manufactured by Tosoh
Corp., molecular weight; 8,400,000) is used. The resulted
weight-average molecular weight in terms of polystyrene is
represented by Mw, the resulted number-average molecular weight in
terms of polystyrene is represented by Mn, and the ratio of them (Q
value=Mw/Mn) is molecular weight distribution. As the measuring
sample, about 5 mg of a polymer is dissolved in 5 ml of
o-dichlorobenzene so as to obtain a concentration of about 1 mg/ml.
The resulted sample solution (400 .mu.l) was injected, and
detection was conducted by a refractive index detector at an
elution solvent flow rate of 1.0 ml/min.
[0027] The component (A) preferably manifests a bimodal molecular
weight distribution curve. When the molecular weight distribution
has single peak, spreading of the molecular weight distribution is
insufficient, and a molded article obtained by molding the
resulting thermoplastic elastomer composition may has deteriorated
extrusion processability, particularly, deteriorated extruded
surface, and deteriorated calender processability.
[0028] The ratio (H=X1/X2) of high molecular weight peak height X1
to low molecular weight peak height X2 in a molecular weight
distribution curve of the component (A) is preferably from 2.0 to
7.0, further preferably from 2.2 to 6.0. When H is too low, bleed
may occur on the surface of a molded article obtained by molding
the resulting thermoplastic elastomer composition. On the other
hand, when H is too high, extrusion processability, particularly
extruded surface may deteriorate, and the extrusion amount may
decrease.
[0029] In the molecular weight distribution curve of the component
(A), the area of low molecular weight parts having chain lengths of
100 .ANG. or less is preferably 3% or less, more preferably 2% or
less. When this area is too large, bleed may occur on the surface
of the final product of the above-mentioned copolymer or a pellet
of the copolymer.
[0030] Heat of fusion of a crystal of the component at temperature
of from 50 to 100.degree. C. is preferably 5 mJ/mg or more, more
preferably 8 mJ/mg or more, when measured by a differential
scanning calorimeter (DSC). When this value is too small, extrusion
processability, particularly shape retaining property of the
copolymer may deteriorate. As the differential scanning
calorimeter, there is used, for example, DSC220 manufactured by
Seiko Instruments Inc., and the measurement is conducted at a rate
of 10.degree. C./min. in temperature rising process.
[0031] The component (A) can be produced by polymerizing ethylene
and .alpha.-olefin using a single reactor or twin reactor in the
presence of a catalyst system obtained by combining the following
components (C) to (E). A three or more reactor may also be used,
providing the constitution conditions of the present invention are
satisfied.
[0032] As the component (C), a vanadium compound represented by the
general formula VO(OR).sub.nX.sub.3-n (wherein, R is a hydrocarbon
group, X is halogen, 0.ltoreq.n.ltoreq.3) can be used, and examples
thereof include VOCl.sub.3, VO(OCH.sub.3)Cl.sub.2,
VO(OCH.sub.3).sub.2Cl, VO(OCH.sub.3).sub.3,
VO(OC.sub.2H.sub.5)Cl.sub.2, VO(OC.sub.2H.sub.5).sub- .2Cl,
VO(OC.sub.2H.sub.5).sub.3, VO(OC.sub.3H.sub.7)Cl.sub.2,
VO(OC.sub.3H.sub.7).sub.2Cl, VO(OC.sub.3H.sub.7).sub.3,
VO(O-iso-C.sub.3H.sub.7)Cl.sub.2, VO(O-iso-C.sub.3H.sub.7).sub.2Cl,
VO(O-iso-C.sub.3H.sub.7).sub.3, VO(O-n-C.sub.4H.sub.9)Cl.sub.2,
VO(O-n-C.sub.4H.sub.9).sub.2Cl, VO(O-n-C.sub.4H.sub.19).sub.3 or
mixtures thereof. Among them, those other than VOCl.sub.3 can be
obtained easily by reacting VOCl.sub.3 with alcohol or reacting
VOCl.sub.3 with VO(OR).sub.3.
[0033] As the component (D), an organoaluminum compound represented
by the general formula R'.sub.mAlX.sub.3-m (wherein, R' is a
hydrocarbon group, X is halogen, 0.ltoreq.n.ltoreq.3) can be used,
and examples thereof include (C.sub.2H.sub.5).sub.2AlCl,
(C.sub.4H.sub.9).sub.2AlCl, (C.sub.6H.sub.13).sub.2AlCl,
(C.sub.2H.sub.5).sub.1.5AlCl.sub.1.5,
(C.sub.4H.sub.9).sub.1.5AlCl.sub.1.5,
(C.sub.6H.sub.13).sub.1.5AlCl.sub.1- .5, C.sub.2H.sub.5AlCl.sub.2,
C.sub.4H.sub.9AlCl.sub.2, C.sub.6H.sub.13AlCl.sub.2 and the
like.
[0034] Though the copolymer of the present invention can be
obtained by using a catalyst system consisting essentially of the
component (C) and the component (D), the following component (E)
may also be combined for the purpose of further reducing the amount
of low molecular weight components which is a main factor of
bleed.
[0035] As the component (E), a halogenated ester compound
represented by the following general formula can be used. 1
[0036] (wherein, R" is an organic group having 1 to 20 carbon
atoms, partially or completely substituted by halogen atoms, and
R'" is a hydrocarbon group having 1 to 20 carbon atoms.). A
compound in which the substituent R" is completely substituted by
chlorine atoms is preferable, and a perchlorocrotonate is further
preferable. Examples thereof include ethyldichloroacetate,
methyltrichloroacetate, ethyltrichloroacetate,
methyldichlorophenylacetate, ethyldichlorophenylacetate,
methylperchlorocrotonate, ethylperchlorocronate,
propylperchlorocrotonate- , isopropylperchlorocrotonate,
butylperchlorocrotonate, cyclopropylperchlorocrotonate,
phenylperchlorocrotonate and the like.
[0037] It is preferable that the molar ratio of the organoaluminum
compound (D) to the vanadium compound (C) is 2.5 or more and the
molar ratio of the halogenated ester compound (E) to the vanadium
compound (C) is 1.5 or more, in the polymerization reaction.
[0038] The component (A) in the present invention can be produced
by using one or more of known Ziegler-Natta catalysts or known
single site catalysts and using a single reactor or two or more
reactor. A known single site catalyst is preferable from the
standpoint of the uniformity of the composition distribution of the
resulting polymer, and examples of such a single site catalyst
include, for example, metallocene-based catalysts described in JP-A
Nos. 58-19309, 60-35005, 60-35006, 60-35007, 60-35008, 61-130314,
3-163088, 4-268307, 9-12790, 9-87313, 10-508055, 11-80233, Japanese
Patent Kohyo Publication No. 10-508055 and the like,
non-metallocene-based complex catalysts described in JP-A Nos.
10-316710, 11-100394, 11-80228, 11-80227, Japanese Patent Kohyo
Publication No. 10-513489, JP-A Nos. 10-338706 and 11-71420. Among
them, a metallocene-based catalysts are generally used. As the
suitable matallocene catalyst of them, a complex of a III to XII
transition metal in periodic table which has at least one
cyclopentadiene type anion skeleton and has a C.sub.1 symmetrical
structure is preferable from the standpoint of the flexibility of
the resulting polymer. Further, as the example of a suitable
production method using a metallocene catalyst in obtaining a
polymer having high molecular weight, a method is exemplified in
which ethylene and .alpha.-olefin are copolymerized in the presence
of an olefin polymerization catalyst comprising the following
(.alpha.), (.beta.) and/or (.gamma.).
[0039] (.alpha.): at least one of transition metal complexes
represented by the following general formulae [I] to [III], 2
[0040] (in each of the above-described general formulae [I] to
[III], M.sup.1 represents a IV group transition metal atom in
periodic table of element, A represents a XVI group atom in
periodic table of element, and J represents a XIV group atom in
periodic table of element. Cp.sup.1 represents a group having a
cyclopentadiene type anion skeleton. Each of X.sup.1, X.sup.2,
R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6
independently represents a hydrogen atom, halogen atom, alkyl
group, aralkyl group, aryl group, substituted silyl group, alkoxy
group, aralkyloxy group, aryloxy group or disubstituted amino
group. X.sup.3 represents a XVI group atom in periodic table of
element. R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6
may optionally bond to form a ring. Two of M.sup.1, A, J, Cp.sup.1,
X.sup.1, X.sup.2, X.sup.3, R.sup.1, R.sup.2, R.sup.3, R.sup.4,
R.sup.5 and R.sup.6 may be the same or different,
respectively.).
[0041] (.beta.): One or more aluminum compounds selected from the
following (.beta.1) to (.beta.3):
[0042] (.beta.1): Organoaluminum compound represented by the
general formula E.sup.1.sub.aAlZ.sub.3-a,
[0043] (.beta.2): Aluminoxane having a structure represented by the
general formula {--Al(E.sup.2)--O--}.sub.b,
[0044] (.beta.3): Aluminoxane having a structure represented by the
general formula
E.sup.3{--Al(E.sup.3)--O--}.sub.cAlE.sup.3.sub.2:
[0045] (wherein, E.sup.1, E.sup.2 and E.sup.3 represent hydrocarbon
groups respectively, and all of E.sup.1, all of E.sup.2 and all of
E.sup.3 may be the same or different. Z represents a hydrogen atom
or halogen atom, and all of Z may be the same or different. "a"
represents a number satisfying 0<a.ltoreq.3, "b" represents an
integer of 2 or more and "c" represents an integer of 1 or
more.).
[0046] (.gamma.) Boron compound of any of the following (.gamma.1)
to (.gamma.3).
[0047] (.gamma.1): Boron compound represented by the general
formula BQ.sup.1Q.sup.2Q.sup.3.
[0048] (.gamma.2): Boron compound represented by the general
formula G+(BQ.sup.1Q.sup.2Q.sup.3Q.sup.4).
[0049] (.gamma.3): Boron compound represented by the general
formula (L-H)+(BQ.sup.1Q.sup.2Q.sup.3Q.sup.4).
[0050] (wherein, B is a boron atom in atomic trivalent, Q.sup.1 to
Q.sup.4 may be the same or different and represent a halogen atom,
hydrocarbon group, halogenated hydrocarbon group, substituted silyl
group, alkoxy group or disubstituted amino group. G.sup.+ is an
inorganic or organic cation, L is a neutral Lewis acid, and
(L-H).sup.+ is a Broensted acid.).
[0051] Specific examples of the inactive hydrocarbon medium used in
preparing a catalyst include aliphatic hydrocarbons such as
propane, butane, pentane, hexane, heptane, octane, decane,
dodecane, kerosene and the like, alicyclic hydrocarbons such as
cyclopentane, cyclohexane, methylcyclopentane and the like,
aromatic hydrocarbons such as benzene, toluene, xylene and the
like, halogenated hydrocarbons such as ethylene chloride,
chlorobenzene, dichloromethane and the like, or mixtures thereof.
The preparation temperature is preferably in the range of from
-100.degree. C. to 250.degree. C., and pressure and time can be set
in any ranges.
[0052] Polymerization of the component (A) is conducted in a
hydrocarbon solvent. Examples of the hydrocarbon solvent include
aliphatic hydrocarbons such as pentane, hexane, heptane, octane,
decane, dodecane, kerosene and the like, alicyclic hydrocarbons
such as cyclohexane, methylcyclopentane, methylcyclohexane and the
like, and aromatic hydrocarbons such as benzene, toluene, xylene
and the like. Also, .alpha.-olefins such as propylene, 1-butene,
1-pentene, 1-hexene and the like can be used as a part of all of
the solvent. The polymerization temperature is preferably from 40
to 160.degree. C., and further preferably from 40 to 80.degree. C.
from the standpoints of productivity and control of molecular
weight.
[0053] The polymerization is conducted under pressure or
atmospheric pressure using a single reactor or a two reactor in
line, and preferably carried out at 0.1 to 5 MPa, particularly
preferably at 0.1 to 2 MPa. The average retention time of the
reaction liquid per one polymerization bath is preferably from 2 to
180 minutes, further preferably from 20 to 120 minutes, and the
polymer concentration is preferably 15 wt % or less, further
preferably 12 wt % or less from the standpoint of reduction of the
viscosity of the reaction liquid.
[0054] As a material used to control the molecular weight of the
component (A), hydrogen, diethylamine, arylchloride
pyridine-N-oxide and the like are exemplified, and hydrogen is
particularly preferable.
[0055] When two reactors are used, the temperatures of the first
reactor and the second reactor can be set arbitrary and the
molecular weight controlling agent can be arbitrary set, and it is
preferable that a polymer having high molecular weight is produced
in the first reactor and a polymer having low molecular weight is
produced in the second reactor, and it is preferable that the
polymerization temperature of the first reactor is from 40 to
60.degree. C., and the polymerization temperature of the second
reactor is from 50 to 80.degree. C. When the polymerization
temperature of the first reactor is too high, the molecular weight
of a polymer having high molecular weight may become insufficient.
When the polymerization temperature of the second reactor is too
low, it may be necessary to use a molecular weight controlling
agent in large amount.
[0056] On the other hand, the molecular weight controlling agent
can be added to either the first reactor or the second reactor or
to both of them. If the use amount in the first reactor is
decreased and the use amount in the second reactor is increased, it
is preferable that sufficient amount of high molecular weight
polymer and low molecular weight polymer can be polymerized.
[0057] The ratio of the production amounts of copolymers in the
first reactor to the second reactor is preferably within the range
from 2.0/0.05 to 1/2.5. Further, a more preferable result is
obtained when the copolymerization is conducted in the range from
2.0/0.1 to 2/1.5.
[0058] The component (A) can be obtained by blending two or more
kinds of polymers.
[0059] Herein, a polymer having high molecular weight and a polymer
having low molecular weight can be polymerized and blended
simultaneously by use of a catalyst system of the known
Ziegler-Natta catalyst or by co-use of known single site catalysts
described above, and this is a method also suitable for mass
production. In this case, a plurality of polymerization reactor are
not necessarily required, and only one reactor may be used without
problem.
[0060] When the component (A) is used as a polyolefin-based resin
modifier, it is preferably made into a pellet.
[0061] As the form of this pellet, sphere, cylinder, lens and cube
are exemplified. These can be produced by a known pellet forming
method, and for example, when the component (A) is melt-mixed and
extruded through an extruder and subjected to hot cut or strand
cut, a pellet in the form of sphere, cylinder or lens is obtained.
In this case, cut may be conducted in any flow such as water flow,
air flow and the like. A pellet in the form of cube is obtained by
mixing the raw material uniformly, then, molding it into a sheet by
a roll and the like, and subjected the molded one to a sheet
pelletizer. Regarding the size, the longest part of a pellet is
preferably 3 cm or less. In the case of a pellet having larger size
than 3 cm, measuring error may increase.
[0062] A pellet of the component (A) is preferably dusted with one
or more of calcium stearate, calcium carbonate, barium sulfate,
silica, talc, stearic acid and polyolefin powder, from the
standpoints of further suppression of mutual adhesion, or
suppression of bridging phenomenon of a pellet in removing out of a
silo and the like. The dusting amount may be controlled depending
on the size and form of a pellet according to demand. In general,
it is preferably added in an amount of 0.05 to 3 parts by weight
based on the pellet. When the addition amount is too low, the
effect for further suppressing mutual adhesion may not be
manifested. When the addition amount is too high, it may be a cause
for decrease in physical property and the like and increase in
production cost. In particular, when the transparency of the final
product is important, a polyolefin powder is preferably used. As
the polyolefin powder, polyethylene-based resins and
polypropylene-based resins are listed.
[0063] The average particle size of a polyolefin powder is
preferably 500 .mu.m or less, particularly preferably 300 .mu.m or
less. When the particle size is larger, adhesion on the surface of
a pellet may not be occurred and the mutual adhesion
property-improving effect may not be obtained.
[0064] The component (B) in the present invention is a
polyolefin-based resin having a tensile stress M.sub.100 measured
according to JIS-K-6251 of 2.5 MPa or more. The component (B)
should has a tensile stress M.sub.100 measured according to
JIS-K-6251 of 2.5 MPa or more, preferably 3.0 MPa or more. When
this value is too low, a molded article obtained by molding the
resulting thermoplastic elastomer composition may be poor in
strength
[0065] Examples of the component (B) include polyethylene-based
resins such as high density polyethylene, middle density
polyethylene, low density polyethylene, LLDPE (linear low density
polyethylene); polypropylene-based resins, polybutene-based resins,
poly-4-methyl-pentene-1, ethylene-vinyl acetate copolymer resin,
ethylene-methyl methacrylate copolymer resin, ethylene-methacrylate
copolymer resin, ethylene-acrylate copolymer resin,
ethylene-methacrylic acid copolyemr resin, ethylene-acrylic acid
copolymer resin, ethylene-styrene copolymer resin and the like.
Further, two or more components (B) may also be co-used.
[0066] The Q value (weight-average molecular chain
length/number-average molecular chain length) of the component (B)
in GPC measurement is preferably 3 or more, more preferably 3.5 or
more, from the standpoint of improvement of the extrusion
processability of a molded article obtained by molding the
resulting thermoplastic elastomer composition. For measuring the Q
value, the method described in the column of the component (A) may
advantageously be used.
[0067] The thermoplastic elastomer composition of the present
invention comprises 5 to 95 wt % of the component (A) and 5 to 95
wt % of the component (B), preferably comprises 10 to 90 wt % of
the component (A) and 10 to 90 wt % of the component (B), more
preferably comprises 20 to 80 wt % of the component (A) and 20 to
80 wt % of the component (B). When the amount of the component (A)
is too low (that is, the amount of the component (B) is too high),
a molded article obtained by molding the resulting thermoplastic
elastomer composition is poor in flexibility and extrusion
processability, particularly, shape retaining property, while when
the amount of the component (A) is too high (that is, the amount of
the component (B) is too low), a molded article obtained by molding
the resulting thermoplastic elastomer composition is poor in
strength.
[0068] The thermoplastic elastomer composition of the present
invention should has a flowability index I according to a test for
flow properties with a capillary rheometer of 1.35 or more,
preferably of 1.40 or more, more preferably of 1.50 or more. When
this index is too low, the non-Newtonian property of melt
flowability is insufficient, and a sufficient effect for improving
extrusion processability is not obtained. Higher flowability index
is preferable from the standpoint of extrusion processability,
providing the constitution conditions of the present invention are
satisfied.
[0069] A test for flow properties with a capillary rheometer and
calculation of flowability index are conducted according to the
following methods.
[0070] Measuring apparatus: Capirograph 1C, manufactured by Toyo
Seiki Seisaku-Sho, Ltd.
[0071] Die: capillary diameter of 1 mm, capillary length of 10
mm
[0072] Temperature: 190.degree. C.
[0073] Shear rate: 12, 37, 61, 122, 365, 608 (s.sup.-1)
[0074] The shear viscosity was measured at each shear rate.
[0075] The flowability index, I=A/B, was calculated from the shear
viscosity ratio (shear viscosity at a shear rate of 12
(s.sup.-1)/shear viscosity at a shear rate of 365 (s.sup.-1)) and
plot (see, FIG. 1) of the shear viscosity at a shear rate of 12
(s.sup.-1) The solid line in the figure is a master curve of EPM
which has a Q value by GPC measurement of 1.8 and has no long chain
branching, and represented by the formula
Y-0.5917.times.10.sup.-3X+1.2640. When the plot of a thermoplastic
elastomer composition shifts toward positive direction of Y axis
(shear viscosity ratio), the non-Newtonian property of the
composition is higher, and it is related to extrusion
processability, for example, melt flow phenomenon of extruded
surface and the like.
[0076] In the present invention, there may be appropriately
compounded, as the additional component, additives such as an
antioxidant, antistatic agent, anti-weathering agent, ultraviolet
absorber, stripping agent, dispersing agent and the like, coloring
agents such as carbon black and the like, fillers such as glass
fiber, carbon fiber, metal fiber, aramide fiber, glass bead,
asbestos, mica, calcium carbonate, potassium titanate whisker,
talc, barium sulfate, glass flake and the like, or other
rubber-like polymers or thermoplastic resins and the like, in
addition to the above-mentioned components.
[0077] The thermoplastic elastomer composition of the present
invention can also be subjected to cross-linking such as sulfur
cross-linking, peroxide cross-linking, metal ion cross-linking,
silane cross-linking, water cross-linking and the like, by
conventionally known methods, if necessary.
[0078] For obtaining the thermoplastic elastomer composition of the
present invention, the components (A) and (B) and additional
components appropriately used may advantageously be kneaded by a
usual kneading machine, for example, a rubber mill, brabender mill,
Banbury mixer, pressure kneading, twin screw extruder and the like.
The kneading machine may be any of closed type machine or open type
machine, and a closed type machine which can be substituted with an
inert gas is preferable. The kneading temperature is a temperature
at which all of the mixed components are melted, and usually from
160 to 250.degree. C., preferably from 180 to 240.degree. C. The
kneading time is usually from about 3 to 10 minutes when a kneading
machine such as a pressure kneader, Banbury mixer and the like is
used, though the kneading time is not determined since it depends
on the kind and amount of the component mixed and the kind of the
kneading machine. In the kneading process, components may be
kneaded at one time, alternatively, there may also be adopted a
multi-step division kneading method in which a part of constituents
components are kneaded, and then the remaining components are added
and the kneading is continued.
[0079] The thermoplastic elastomer composition and
ethylene-.alpha.-olefin copolymer of the present invention are
excellent particularly as a material for extrusion molding, and can
be melt-extruded through an extruder equipped with a mold in the
form of the molded article, at the tip of the extruder, and cooled
and cut to obtain a heteromorphic extrusion-molded article.
[0080] Further, the thermoplastic elastomer composition and
ethylene-.alpha.-olefin copolymer of the present invention are
excellent particularly as a material of calender molding, and a
calender molded article can be obtained by a sheeting process in
which a smooth sheet having higher thickness accuracy is produced
continuously, a doubling process in which a sheet having higher
thickness accuracy containing no pin hole is produced continuously
in laminating the same or different thermoplastic elastomer
compositions and thermoplastic resin compositions, a topping
process in which a composite is continuously produced by laminating
cloth and the like onto a sheet, a friction process in which a
thermoplastic elastomer composition is imprinted into cloth for the
purpose of improving adhesion, or a profiling process in which a
carved pattern is made on the surface of a roll and this pattern is
transcribed continuously onto the surface of a sheet.
[0081] The thermoplastic elastomer composition and
ethylene-.alpha.-olefin copolymer of the present invention can be
used in parts such as a packing, housing and the like of automobile
interior or exterior parts and weak electric parts, industrial
parts, water-proof parts and the like, in stead of the conventional
soft vinyl chloride-based resins. Among them, due to flexibility,
excellent extrusion processability, further, the absence of bleed,
they can be used in a hose, tube, gasket and packing. Regarding use
examples thereof, as the hose and tube use, there are listed an air
hose, water hose, reinforcing agent-containing air hose,
reinforcing agent-containing water hose and medical tube, as the
gasket use, there are listed an aluminum sash sealing gasket and
gasket around doors of an automobile, and as the packing use, there
is listed a packing of a refrigerator door.
EXAMPLES
[0082] The following examples further illustrate the present
invention specifically, but do not limit the scope of the present
invention. In the present invention, the term excellent extrusion
processability means that the surface skin of the extrusion-molded
article is smooth and the appearance of the resulting final product
does not deteriorate. In the present invention, the term excellent
calender processability means that sheet removal from the roll
surface can be conducted easily.
[0083] [I] Production and Evaluation of Copolymer
[0084] Measurements were conducted as described below.
[0085] (1) Measurement by Differential Scanning Calorimeter
(DSC)
[0086] Measurements were conduced at a rate of 10.degree. C./min.
in any of temperature rising process and constant temperature
process, using a differential scanning calorimeter (DSC220C,
manufactured by Seiko Instruments Inc.).
[0087] (2) Measurement by GPC
[0088] The GPC measurement was conducted at an elution temperature
of 140.degree. C. using 150C manufactured by Waters, Shodex Packed
ColumnA-80 M (manufactured by Showa Denko K.K.) as a column, and
polystyrene (manufactured by Tosoh Corp., molecular weight;
68-8,400,000) as a molecular weight reference material. The
resulted weight-average molecular weight in terms of polystyrene
was represented by Mw, the resulted number-average molecular weight
in terms of polystyrene was represented by Mn, and the ratio of
them (Q value) was molecular weight distribution, and the higher
molecular weight peak height (X1), lower molecular weight peak
height (X2) in a molecular weight distribution curve and the ratio
(H=X1/X2) of them were measured. For preparing a measuring sample,
about 5 mg of a polymer was dissolved in 5 ml of o-dichlorobenzene
so as to obtain a concentration of about 1 mg/ml. The resulted
sample solution (400 .mu.l) was injected, and detection was
conducted by a refractive index detector at an elution solvent flow
rate of 1.0 ml/min.
[0089] (3) Flexibility
[0090] The hardness of a copolymer was measured according to
JIS-K-6253.
[0091] (4) Tensile Stress
[0092] A copolymer was press-molded at 150.degree. C. to obtain a
sheet of 2 mm thickness, then, the tensile stress M.sub.100 of the
copolymer was measured according to JIS-K-6251. A specimen was made
by using No. 3 dumbbell.
[0093] (5) Preparation and Evaluation of Copolymer Pellet
[0094] A copolymer was heated for 30 minutes in a Geer oven at
100.degree. C., then, a sheet of 4 mm thickness was molded by 10
inch open rolls. This sheet was ground by a sheet pelletizer to
obtain a pellet in the form of cube. This pellet was dusted with
0.18 g of calcium stearate and 0.18 g of Irganox 1076 (antioxidant,
manufactured by Chiba Specialty Chemicals) per 150 g of the pellet,
and this was filled in a glass beaker (diameter: 8.6 cm), charged
with a load of 1900 g, left for 14 hours under atmosphere of
40.degree. C., then, the mutual adhesion of the pellet was
evaluated.
[0095] Judge of Mutual Adhesion of Pellet
[0096] 1: The form of a pellet is completely kept, and no adhesion
is found between pellets at all.
[0097] 2: Though the form of a pellet is kept, and adhesion is
found between pellets.
[0098] 3: The form of a pellet is not kept, and adhesion is found
between pellets.
[0099] (6) Evaluation of Bleeding Property
[0100] A copolymer was press-molded at 15.degree. C. to obtain a
sheet of 2 mm thickness, then, left for 48 hours, and the bleeding
property of the surface of the sheet was evaluated.
[0101] Judge of Bleeding Property
[0102] .largecircle.: The surface of a sheet is clean, and no
stickiness is found by finger touch.
[0103] .DELTA.: The surface of a sheet is somewhat cloudy, and
stickiness is found by finger touch.
[0104] X: An oil film is observed on the surface of a sheet.
[0105] (7) Evaluation of Extrusion Processability
[0106] The pellet obtained in the method of (5) was
extrusion-molded using a 40 mm .phi. single screw extruder (full
flight screw L/D28) through a flat die of 70 mm width, and the
extruded surface and appearance of the resulted molded article were
observed.
[0107] Judge of Extruded Surface
[0108] .largecircle.: Extruded surface is smooth.
[0109] X: Extruded surface is not smooth, but rough.
[0110] Judge of Appearance
[0111] .largecircle.: Extrusion-molded article keeps edge in the
form of a die even after molding.
[0112] X: Molded article causes disintegration after
extrusion-molding, and edge in the form of a die is not kept.
Example 1
Synthesis of component (A)-1
[0113] Into the lower portion of a 100 L reactor made of stainless
steel equipped with a stirrer were continuously fed 62.8 kg of
hexane as a polymerization solvent and ethylene and propylene at
rates of 5.90 kg and 22.44 kg per hour, respectively.
VO(O-iso-C.sub.3H.sub.7).sub.3 and ethylaluminum sesquichloride
(EASC) were fed continuously as a catalyst, at ratios of 2.22 g and
7.79 g per hour, respectively, and the temperature of the
polymerization chamber was kept at 50.degree. C. A part of the
polymerization liquid in the first reactor was extracted, and a
polymer was allowed to deposit and dried by steam stripping. A
copolymer was thus obtained at a rate of 4.6 kg per hour. The
control of the molecular weight was conducted by using hydrogen.
The results are shown in Table 1.
Example 2
Synthesis of component (A)-2
[0114] According to the same manner as in Example 1, hexane was fed
at a rate of 62.8 kg per hour and ethylene and propylene were fed
at rates of 5.44 kg and 23.39 kg per hour, respectively,
continuously. VO(O-iso-C.sub.3H.sub.7).sub.3 and ethylaluminum
sesquichloride (EASC) were fed continuously as a catalyst, at
ratios of 0.70 g and 2.49 g per hour, respectively, and the
temperature of the polymerization chamber was kept at 50.degree. C.
A part of the polymerization liquid in the first reactor was
extracted, and a polymer was allowed to deposit and dried by steam
stripping. A copolymer was thus obtained at a rate of 2.6 kg per
hour. The control of the molecular weight was conducted by using
hydrogen. The results are shown in Table 1.
Example 3
Synthesis of component (A)-3
[0115] According to the same manner as in Example 1, hexane was fed
at a rate of 62.8 kg per hour and ethylene and propylene were fed
at rates of 5.44 kg and 25.78 kg per hour, respectively,
continuously. VO(O-iso-C.sub.3H.sub.7).sub.3 and ethylaluminum
sesquichloride (EASC) were fed continuously as a catalyst, at
ratios of 0.64 g and 2.24 g per hour, respectively, and the
temperature of the polymerization chamber was kept at 50%. A part
of the polymerization liquid in the first reactor was extracted,
and a polymer was allowed to deposit and dried by steam stripping.
A copolymer was thus obtained at a rate of 2.0 kg per hour. The
control of the molecular weight was conducted by using hydrogen.
The results are shown in Table 1.
Example 4
(Synthesis of component (A)-4
[0116] According to the same manner as in Example 1, hexane was fed
at a rate of 62.8 kg per hour and ethylene and propylene were fed
at rates of 5.44 kg and 23.39 kg per hour, respectively,
continuously. VO(O-iso-C.sub.3H.sub.7).sub.3 and ethylaluminum
sesquichloride (EASC) were fed continuously as a catalyst, at
ratios of 0.78 g and 2.72 g per hour, respectively, and the
temperature of the polymerization chamber was kept at 50.degree. C.
A part of the polymerization liquid in the first reactor was
extracted, and a polymer was allowed to deposit and dried by steam
stripping. A copolymer was thus obtained at a rate of 2.2 kg per
hour. The control of the molecular weight was conducted by using
hydrogen. The results are shown in Table 3.
Comparative Example 1
[0117] According to the same manner as in Example 1, hexane was fed
at a rate of 6-2.8 kg per hour and ethylene and propylene were fed
at rates of 5.44 kg and 23.39 kg per hour, respectively,
continuously. Additionally, 5-ethylidene-2-norbornene as the third
component was fed at a rate of 0.81 kg per hour.
VO(O-iso-C.sub.3H.sub.7).sub.3 and ethylaluminum sesquichloride
(EASC) were fed continuously as a catalyst, at ratios of 6.95 g and
24.33 g per hour, respectively, and the temperature of the
polymerization chamber was kept at 50.degree. C. A part of the
polymerization liquid in the first reactor was extracted, and a
polymer was allowed to deposit and dried by steam stripping. A
copolymer was thus obtained at a rate of 4.9 kg per hour. The
control of the molecular weight was conducted by using hydrogen.
The results are shown in Table 2.
Comparative Example 2
[0118] According to the same manner as in Example 1, hexane was fed
at a rate of 120.3 kg per hour and ethylene and propylene were fed
at rates of 4.34 kg and 8.69 kg per hour, respectively,
continuously. VO(O-iso-C.sub.3H.sub.7).sub.3 and ethylaluminum
sesquichloride (EASC) were fed continuously as a catalyst, at
ratios of 2.27 g and 4.77 g per hour, respectively, and the
temperature of the polymerization chamber was kept at 55.degree. C.
A part of the polymerization liquid in the first reactor was
extracted, and a polymer was allowed to deposit and dried by steam
stripping. A copolymer was thus obtained at a rate of 4.0 kg per
hour. The control of the molecular weight was conducted by using
hydrogen. The results are shown in Table 2.
Comparative Example 3
[0119] According to the same manner as in Example 1, hexane was fed
at a rate of 108.4 kg per hour and ethylene and propylene were fed
at rates of 6.45 kg and 15.1 kg per hour, respectively,
continuously. VOCl.sub.3, ethanol and ethylaluminum sesquichloride
(EASC) were fed continuously as a catalyst, at ratios of 2.9 g, 1.4
g and 17.1 g per hour, respectively, and the temperature of the
polymerization chamber was kept at 52.degree. C. A part of the
polymerization liquid in the first reactor was extracted, and a
polymer was allowed to deposit and dried by steam stripping. A
copolymer was thus obtained at a rate of 6.5 kg per hour. The
control of the molecular weight was conducted by using hydrogen.
The results are shown in Table 3.
[0120] The results in Tables 1 to 3 teach the following matters.
The ethylene-propylene copolymers of Examples 1 to 4 satisfying the
conditions of the present invention do not cause bleeding of lower
molecular weight components, and manifest excellent flexibility,
extrusion processability, and handling property of a pellet.
[0121] [II] Production and Evaluation of Thermoplastic Elastomer
Composition
[0122] The compositions shown in Tables 4 to 8 were kneaded for 5
minutes at a temperature of 130.degree. C. and a screw revolution
of 100 rpm using a Plasti-Corder with a roller mixer (manufactured
by Brabender OHG). The compositions were press-molded at
150.degree. C., and subjected to the following tests. They were
evaluated in the same manner except that the kneading temperature
was 200.degree. C. and the press-molding temperature was
200.degree. C. in Brabender Plasti-Corder in example 8 and
Comparative Example 3,
[0123] Tensile test: The tensile stress (M.sub.100), tensile
strength at break (TB) and elongation at break (EB) were measured
according to JIS-K-6251.
[0124] Hardness: The hardness by Duro type A hardener was measured
according to JIS-K-6253.
[0125] Flowability: The melt flow rate at 190.degree. C. or
230.degree. C. was measured according to JIS-K-7210.
[0126] A test for flow properties with a capillary rheometer and
calculation of flowability index: Each Shear viscosity was measured
using Capirograph 1C (manufactured by Toyo Seiki Seisaku-Sho, Ltd.)
at a furnace body temperature of 190.degree. C., a capillary
diameter of 1 mm and a capillary length of 10 mm, at a shear rate
of 12, 37, 61, 122, 365, 608 (s.sup.-1).
[0127] The flowability index was calculated from the shear
viscosity ratio (shear viscosity at a shear rate of 12
(s.sup.-1)/shear viscosity at a shear rate of 365 (s.sup.-1)) and
plot (see, FIG. 1) of the shear viscosity at a shear rate of 12
(s.sup.-1), providing the flowability index I=A/B.
[0128] Extrusion processability: A thermoplastic elastomer
composition was allowed to flow under condition of a shear rate of
122 (s.sup.-1)) in the above-described test for flow properties
with a capillary rheometer, and the extruded surface of the
composition was observed.
[0129] Judge of Extrusion Processability
[0130] .largecircle.: Extruded surface is smooth.
[0131] .DELTA.: Extruded surface reveals slight roughness.
[0132] X: Extruded surface is not smooth, but rough.
[0133] Bleeding Property:
[0134] Evaluation of Bleeding Property
[0135] A copolymer was press-molded at 150.degree. C. or
200.degree. C. to obtain a sheet of 2 mm thickness, then, left for
48 hours, and the bleeding property of the surface of the sheet was
evaluated.
[0136] Judge of Bleeding Property
[0137] .largecircle.: The surface of a sheet is clean, and no
stickiness is found by finger touch.
[0138] .DELTA.: The surface of a sheet is somewhat cloudy, and
stickiness is found by finger touch.
[0139] X: An oil film is observed on the surface of a sheet.
Examples 5 to 13, 15 to 17 and Comparative Examples 4 to 8, 10 to
12
[0140] The results in Tables 4 to 8 teach the following matters.
The thermoplastic elastomer compositions obtained by using the
ethylene-propylene copolymer, component (A)-1 satisfying the
conditions of the present invention are excellent in flexibility
and extrusion processability.
Example 14 and Comparative Example 9
[0141] The compositions shown in Table 9 were melt-kneaded for 10
minutes at a rotor revolution of 50 rpm using a 16 L sealed type
mixer. Then, a sheet of 4 mm thickness was molded by 8 inch open
rolls, and was ground by a sheet pelletizer to obtain a pellet in
the form of cube. This pellet was dusted with 0.12 g of calcium
stearate and 0.12 g of Irganox 1076 (antioxidant, manufactured by
Chiba Specialty Chemicals) per 100 g of the pellet, then, this was
processed into a tube having an outer diameter of 12 mm and a
thickness of 1.5 mm, using a 50 mm .phi. single screw extruder
(screw L/D=24), at a screw revolution of 30 rpm, a die temperature
of 160.degree. C., an adapter temperature of 160.degree. C. and a
cylinder temperatures from 130 to 160.degree. C., a drawing rate of
3.5 m/min., and the extruded surface of the resulted tube was
observed.
[0142] Judge of Extrusion Processability
[0143] .largecircle.: Extruded surface is smooth.
[0144] X: Extruded surface is not smooth, but rough.
1 TABLE 1 Example 1 Example 2 Example 3 Ethylene content wt % 73.1
76.3 66.3 Propylene content wt % 26.9 23.7 33.7 END content wt % 0
0 0 ML.sub.1+4100.degree. C. 42.3 40.4 55.3 GPC measurement result
Q Mw/Mn 7.7 9.0 10.1 Mn 4.1 .times. 10.sup.4 3.5 .times. 10.sup.4
4.1 .times. 10.sup.4 Mw 31.8 .times. 10.sup.4 31.4 .times. 10.sup.4
41.4 .times. 10.sup.4 H X1/X2 2.4 2.0 2.6 Molecular weight Bimodal
Bimodal Bimodal distribution form Area of lower molecular % 1.0 0.6
0.4 weight parts having chain lengths of 100 .ANG. or less DSC
measurement result Fusion heat of crystal mJ/mg 9.2 17.5 11.7 in
the range from 50 to 100.degree. C. M.sub.100 MPa 1.3 1.8 1.3
Hardness (Duro A) 57 68 59 Mutual adhesion of 1 1 1 pellet Bleeding
property .smallcircle. .DELTA. .smallcircle.
[0145]
2 TABLE 2 Comparative Comparative example 1 example 2 Ethylene
content wt % 61.9 80.2 Propylene content wt % 30.8 19.8 ENB content
wt % 7.3 0 ML.sub.1+4100.degree. C. 30.0 36.0 GPC measurement
result Q Mw/Mn 8.0 4.5 Mn 2.8 .times. 10.sup.4 5.0 .times. 10.sup.4
Mw 22.6 .times. 10.sup.4 22.5 .times. 10.sup.4 H X1/X2 1.6
Molecular weight distribution form Bimodal Bimodal Area of lower
molecular % 1.3 0.5 weight parts having chain lengths of 100 .ANG.
or less Fusion heat of crystal in the mJ/mg 1.5 range from 50 to
100.degree. C. M.sub.100 MPa 0.8 1.9 Hardness (Duro A) 43 70 Mutual
adhesion of pellet 2 2 Bleeding property .smallcircle. x
[0146]
3 TABLE 3 Comparative Example 4 example 3 Ethylene content wt %
71.0 73.0 Propylene content wt % 29.0 27.0 ML.sub.1+4100.degree. C.
40 52 GPC measurement result Q Mw/Mn 10.3 1.8 Mn 3.3 .times.
10.sup.4 16.2 .times. 10.sup.4 Mw 34.5 .times. 10.sup.4 29.6
.times. 10.sup.4 H X1/X2 2.0 Molecular weight Bimodal Monomodal
distribution form Area of lower molecular % 0.6 0.0 weight parts
having chain lengths of 100 .ANG. or less DSC measurement result
Fusion heat of crystal in the mJ/mg 12.1 0.7 range from 50 to
100.degree. C. M.sub.100 MPa 1.3 1.4 Extrusion processing condition
Screw revolution rpm 40 45 Die temperature .degree. C. 200 180
Cylinder temperature .degree. C. 50.about.130 110.about.180
Extruded surface .smallcircle. x Appearance .smallcircle. x
[0147]
4 TABLE 4 Exam- Exam- Example Example ple ple Unit 5 6 7 8 (A)-1 wt
% 70 60 50 30 (B)-1 wt % 30 40 50 70 Antioxidant wt % 0.12 0.12
0.12 0.12 M100 MPa 1.8 2.1 2.4 2.9 TB MPa 2.7 4.6 6.4 7.0 EB % 740
930 870 840 Hardness Duro A 68 70 75 79 MFR190.degree. C. g/10 1.0
1.2 2.4 3.8 minute Flowability index I A/B 1.70 1.96 2.21 2.77
Extrusion .smallcircle. .smallcircle. .smallcircle. .smallcircle.
processability Bleeding property .smallcircle. .smallcircle.
.smallcircle. .smallcircle.
[0148]
5 TABLE 5 Example Unit 9 Example 10 Example 11 (A)-1 wt % 70 60 50
(B)-2 wt % 30 40 50 Antioxidant wt % 0.12 0.12 0.12 M100 MPa 1.7
2.1 2.3 TB MPa 2.8 7.4 11.6 EB % 740 830 810 Hardness Duro A 69 71
74 MFR190.degree. C. g/10 0.6 0.8 1.1 Flowability index I minute
1.67 1.65 1.94 Extrusion A/B .smallcircle. .smallcircle.
.smallcircle. processability Bleeding property .smallcircle.
.smallcircle. .smallcircle.
[0149]
6 TABLE 6 Example Example Example Example Example Unit 12 13 15 16
17 (A)-1 wt % 70 50 49 60 80 (B)-2 wt % 20 (B)-3 wt % 30 (B)-4 wt %
50 (B)-5 wt % 30 (B)-6 wt % 21 20 (B)-7 wt % 20 Antioxidant wt %
0.12 0.12 0.12 0.12 0.12 M100 MPa 3.2 2.1 2.7 2.0 2.4 TB MPa 3.2
9.7 11.5 9.2 2.5 EB % 300 940 1065 1045 320 Hardness Duro A 77 72
80 72 81 MFR190.degree. C. g/10 0.9 1.3 1.1 0.8 0.5 minute
Flowability index I A/B 1.52 2.38 1.52 1.35 1.38 Extrusion
.smallcircle. .smallcircle. .smallcircle. .smallcircle. .DELTA.
processability Bleeding property .smallcircle. .smallcircle.
.smallcircle. .smallcircle. .smallcircle.
[0150]
7 TABLE 7 Com- Com- Com- Com- parative parative parative parative
example example example example Unit 4 5 6 7 (B)-1 wt % 100 (B)-2
wt % 100 (B)-3 wt % 100 (B)-4 wt % 100 M100 MPa 4.0 3.8 3.2 TB MPa
9.0 17.9 10.5 EB % 800 750 860 Hardness Duro A 84 85 100 81
MFR190.degree. C. g/10 5.6 2.3 8.0 5.4 minute Flowability index I
A/B 3.44 2.69 4.53 1.57 Extrusion .smallcircle. .smallcircle.
.smallcircle. .smallcircle. processability Bleeding property
.smallcircle. .smallcircle. .smallcircle. .smallcircle.
[0151]
8 TABLE 8 Com- Com- Com- Com- parative parative parative parative
example example example example Unit 8 10 11 12 (C) wt % 70 (B)-1
wt % 30 (B)-5 wt % 100 (B)-6 wt % 100 (B)-7 wt % 100 Antioxidant wt
% 0.12 M100 MPa 1.8 5.9 4.2 TB MPa 2.7 13.0 32.1 27.5 EB % 660 760
720 50 Hardness Duro A 68 94 85 100 MFR190.degree. C. g/10 6.0 5.1
5.1 minute Flowability index I A/B 1.13 3.36 1.27 2.04 Extrusion x
.smallcircle. x .smallcircle. processability Bleeding property
.smallcircle. .smallcircle. .smallcircle. .smallcircle.
[0152]
9 TABLE 9 Comparative Unit Example 14 example 9 (A)-1 wt % 60 (B)-2
wt % 40 40 (C) wt % 60 Flowability index I A/B 1.34 Extrusion
processability .smallcircle. x
[0153] (B)-1: Ethylene-methyl methacrylate copolymer resin (methyl
methacrylate content: 25 wt %, MFR 190.degree. C.=5.6 under a load
of 2.16 kg)
[0154] (B)-2: Ethylene-vinyl acetate copolymer resin (vinyl acetate
content: 26 wt %, MFR 190.degree. C.=2.3 under a load of 2.16
kg)
[0155] (B)-3: Random polypropylene (MFR 230.degree. C.=8.5 under a
load of 2.16 kg)
[0156] (B)-4: Ethylene-butene-1 copolymer resin (butene-1 content:
19 wt %, density=0.882 g/cm.sup.3, MFR 190.degree. C.=5.4 under a
load of 2.16 kg)
[0157] (B)-5: Ethylene-vinyl acetate copolymer resin (vinyl acetate
content: 10 wt %, MFR 190.degree. C.=6.0 under a load of 2.16
kg)
[0158] (B)-6: Ethylene-hexene-1 copolymer resin (hexane-1 content:
17 wt %, density=0.885 g/cm.sup.3, MFR 190.degree. C.=5.1 under a
load of 2.16 kg)
[0159] (B)-7: High density polyethylene 230J (manufactured by
Idemitsu Petrochemical Co., Ltd.)
[0160] (C): Ethylene-propylene copolymer (propylene content: 27.0
wt %, Mooney viscosity: ML.sub.1+4100.degree. C.=52, Q value in QPC
measurement=1.8, tensile stress M100=1.4 Mpa, revealing a monomodal
molecular weight distribution curve)
[0161] Antioxidant: Irganox 1076 (antioxidant, manufactured by
Chiba Specialty Chemicals)
[0162] As described above, according to the present invention,
there are obtained a thermoplastic elastomer composition which has
excellent flexibility and processability, manifests no bleeding of
lower molecular weight component, and is excellent particular in
extrusion processability and calender processability, and an
extrusion-molded article obtained by extrusion-molding this
thermoplastic elastomer composition, or a calender-molded article
obtained by calender-molding this thermoplastic elastomer
composition, and an ethylene-.alpha.-olefin copolymer.
* * * * *