GB2058092A - Ethylene-alpha-olefin copolymer powder for powder molding - Google Patents
Ethylene-alpha-olefin copolymer powder for powder molding Download PDFInfo
- Publication number
- GB2058092A GB2058092A GB27341A GB8027341A GB2058092A GB 2058092 A GB2058092 A GB 2058092A GB 27341 A GB27341 A GB 27341A GB 8027341 A GB8027341 A GB 8027341A GB 2058092 A GB2058092 A GB 2058092A
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- Prior art keywords
- powder
- ethylene
- alpha
- olefin copolymer
- melt index
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- 239000000843 powder Substances 0.000 title claims abstract description 157
- 239000004711 α-olefin Substances 0.000 title claims abstract description 53
- 229920000089 Cyclic olefin copolymer Polymers 0.000 title claims abstract description 34
- 238000000465 moulding Methods 0.000 title claims abstract description 21
- 239000002245 particle Substances 0.000 claims abstract description 53
- 229920001577 copolymer Polymers 0.000 claims abstract description 39
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims abstract description 24
- 239000005977 Ethylene Substances 0.000 claims abstract description 24
- 239000003054 catalyst Substances 0.000 claims abstract description 24
- 238000009826 distribution Methods 0.000 claims abstract description 16
- 239000000155 melt Substances 0.000 claims abstract description 11
- 238000010557 suspension polymerization reaction Methods 0.000 claims abstract description 9
- 238000006116 polymerization reaction Methods 0.000 claims description 28
- 239000000203 mixture Substances 0.000 claims description 17
- -1 siloxane compound Chemical class 0.000 claims description 11
- 125000004432 carbon atom Chemical group C* 0.000 claims description 10
- 150000002430 hydrocarbons Chemical group 0.000 claims description 10
- 150000001875 compounds Chemical class 0.000 claims description 9
- 125000005843 halogen group Chemical group 0.000 claims description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 5
- 239000007795 chemical reaction product Substances 0.000 claims description 5
- 229910052719 titanium Inorganic materials 0.000 claims description 5
- 239000010936 titanium Substances 0.000 claims description 5
- 239000000470 constituent Substances 0.000 claims description 4
- 229910052751 metal Inorganic materials 0.000 claims description 4
- 239000002184 metal Substances 0.000 claims description 4
- 150000003682 vanadium compounds Chemical class 0.000 claims description 4
- 150000002901 organomagnesium compounds Chemical class 0.000 claims description 3
- 125000002734 organomagnesium group Chemical group 0.000 claims description 3
- 230000000737 periodic effect Effects 0.000 claims description 3
- 229910052787 antimony Inorganic materials 0.000 claims description 2
- 229910052732 germanium Inorganic materials 0.000 claims description 2
- 125000004435 hydrogen atom Chemical group [H]* 0.000 claims description 2
- 229910052710 silicon Inorganic materials 0.000 claims description 2
- 229910052718 tin Inorganic materials 0.000 claims description 2
- 229910052725 zinc Inorganic materials 0.000 claims description 2
- 239000007787 solid Substances 0.000 claims 2
- 229910052796 boron Inorganic materials 0.000 claims 1
- 230000000379 polymerizing effect Effects 0.000 claims 1
- 125000002524 organometallic group Chemical group 0.000 abstract 1
- 239000011949 solid catalyst Substances 0.000 description 30
- VLKZOEOYAKHREP-UHFFFAOYSA-N n-Hexane Chemical compound CCCCCC VLKZOEOYAKHREP-UHFFFAOYSA-N 0.000 description 27
- 230000000052 comparative effect Effects 0.000 description 23
- 238000000034 method Methods 0.000 description 23
- VXNZUUAINFGPBY-UHFFFAOYSA-N 1-Butene Chemical compound CCC=C VXNZUUAINFGPBY-UHFFFAOYSA-N 0.000 description 20
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 13
- 239000001257 hydrogen Substances 0.000 description 13
- 229910052739 hydrogen Inorganic materials 0.000 description 13
- 238000011156 evaluation Methods 0.000 description 11
- 238000001175 rotational moulding Methods 0.000 description 11
- 238000000227 grinding Methods 0.000 description 10
- 238000000576 coating method Methods 0.000 description 8
- 238000012360 testing method Methods 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 7
- 239000008188 pellet Substances 0.000 description 7
- 239000011347 resin Substances 0.000 description 7
- 229920005989 resin Polymers 0.000 description 7
- 229920001179 medium density polyethylene Polymers 0.000 description 6
- 239000004701 medium-density polyethylene Substances 0.000 description 6
- OFBQJSOFQDEBGM-UHFFFAOYSA-N n-pentane Natural products CCCCC OFBQJSOFQDEBGM-UHFFFAOYSA-N 0.000 description 6
- 230000000704 physical effect Effects 0.000 description 6
- 239000004698 Polyethylene Substances 0.000 description 5
- 239000011248 coating agent Substances 0.000 description 5
- 238000001816 cooling Methods 0.000 description 5
- 229920001903 high density polyethylene Polymers 0.000 description 5
- 239000004700 high-density polyethylene Substances 0.000 description 5
- 229920000573 polyethylene Polymers 0.000 description 5
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 150000003623 transition metal compounds Chemical class 0.000 description 4
- LIKMAJRDDDTEIG-UHFFFAOYSA-N 1-hexene Chemical compound CCCCC=C LIKMAJRDDDTEIG-UHFFFAOYSA-N 0.000 description 3
- UHOVQNZJYSORNB-UHFFFAOYSA-N Benzene Chemical compound C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 description 3
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 238000007334 copolymerization reaction Methods 0.000 description 3
- 230000001186 cumulative effect Effects 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 239000006260 foam Substances 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 239000010410 layer Substances 0.000 description 3
- 238000002156 mixing Methods 0.000 description 3
- 238000009700 powder processing Methods 0.000 description 3
- 239000011541 reaction mixture Substances 0.000 description 3
- 239000011435 rock Substances 0.000 description 3
- 239000002904 solvent Substances 0.000 description 3
- 229910001220 stainless steel Inorganic materials 0.000 description 3
- 239000010935 stainless steel Substances 0.000 description 3
- XJDNKRIXUMDJCW-UHFFFAOYSA-J titanium tetrachloride Chemical compound Cl[Ti](Cl)(Cl)Cl XJDNKRIXUMDJCW-UHFFFAOYSA-J 0.000 description 3
- WSSSPWUEQFSQQG-UHFFFAOYSA-N 4-methyl-1-pentene Chemical compound CC(C)CC=C WSSSPWUEQFSQQG-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- KAKZBPTYRLMSJV-UHFFFAOYSA-N Butadiene Chemical compound C=CC=C KAKZBPTYRLMSJV-UHFFFAOYSA-N 0.000 description 2
- VQTUBCCKSQIDNK-UHFFFAOYSA-N Isobutene Chemical compound CC(C)=C VQTUBCCKSQIDNK-UHFFFAOYSA-N 0.000 description 2
- RRHGJUQNOFWUDK-UHFFFAOYSA-N Isoprene Chemical compound CC(=C)C=C RRHGJUQNOFWUDK-UHFFFAOYSA-N 0.000 description 2
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 239000001273 butane Substances 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- DIOQZVSQGTUSAI-UHFFFAOYSA-N decane Chemical compound CCCCCCCCCC DIOQZVSQGTUSAI-UHFFFAOYSA-N 0.000 description 2
- 229920001971 elastomer Polymers 0.000 description 2
- 238000010528 free radical solution polymerization reaction Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 229920001684 low density polyethylene Polymers 0.000 description 2
- 239000004702 low-density polyethylene Substances 0.000 description 2
- UAEPNZWRGJTJPN-UHFFFAOYSA-N methylcyclohexane Chemical compound CC1CCCCC1 UAEPNZWRGJTJPN-UHFFFAOYSA-N 0.000 description 2
- IJDNQMDRQITEOD-UHFFFAOYSA-N n-butane Chemical compound CCCC IJDNQMDRQITEOD-UHFFFAOYSA-N 0.000 description 2
- 150000002902 organometallic compounds Chemical class 0.000 description 2
- 239000004482 other powder Substances 0.000 description 2
- 239000001294 propane Substances 0.000 description 2
- 239000005060 rubber Substances 0.000 description 2
- 238000005029 sieve analysis Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 150000003609 titanium compounds Chemical class 0.000 description 2
- VOITXYVAKOUIBA-UHFFFAOYSA-N triethylaluminium Chemical compound CC[Al](CC)CC VOITXYVAKOUIBA-UHFFFAOYSA-N 0.000 description 2
- WPWHSFAFEBZWBB-UHFFFAOYSA-N 1-butyl radical Chemical compound [CH2]CCC WPWHSFAFEBZWBB-UHFFFAOYSA-N 0.000 description 1
- XDTMQSROBMDMFD-UHFFFAOYSA-N Cyclohexane Chemical compound C1CCCCC1 XDTMQSROBMDMFD-UHFFFAOYSA-N 0.000 description 1
- 229910019438 Mg(OC2H5)2 Inorganic materials 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- 241001198066 Solanum aethiopicum Species 0.000 description 1
- 235000018650 Solanum gilo Nutrition 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 125000002723 alicyclic group Chemical group 0.000 description 1
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 description 1
- 150000001336 alkenes Chemical class 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 235000006708 antioxidants Nutrition 0.000 description 1
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000994 depressogenic effect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- DLRHRQTUCJTIIV-UHFFFAOYSA-N diethoxy(ethyl)alumane Chemical compound CC[O-].CC[O-].CC[Al+2] DLRHRQTUCJTIIV-UHFFFAOYSA-N 0.000 description 1
- HJXBDPDUCXORKZ-UHFFFAOYSA-N diethylalumane Chemical compound CC[AlH]CC HJXBDPDUCXORKZ-UHFFFAOYSA-N 0.000 description 1
- 230000006353 environmental stress Effects 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000003063 flame retardant Substances 0.000 description 1
- 238000005243 fluidization Methods 0.000 description 1
- 239000004088 foaming agent Substances 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 150000004820 halides Chemical class 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 239000012760 heat stabilizer Substances 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000011256 inorganic filler Substances 0.000 description 1
- 239000003350 kerosene Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- GYNNXHKOJHMOHS-UHFFFAOYSA-N methyl-cycloheptane Natural products CC1CCCCCC1 GYNNXHKOJHMOHS-UHFFFAOYSA-N 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 238000010137 moulding (plastic) Methods 0.000 description 1
- 125000004108 n-butyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- TVMXDCGIABBOFY-UHFFFAOYSA-N octane Chemical compound CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 description 1
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 description 1
- 239000012766 organic filler Substances 0.000 description 1
- YWAKXRMUMFPDSH-UHFFFAOYSA-N pentene Chemical compound CCCC=C YWAKXRMUMFPDSH-UHFFFAOYSA-N 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 239000004014 plasticizer Substances 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 description 1
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 description 1
- 239000003507 refrigerant Substances 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 238000007873 sieving Methods 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 229910052720 vanadium Inorganic materials 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical group [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000001993 wax Substances 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F210/00—Copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond
- C08F210/16—Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
Abstract
Ethylene-alpha-olefin copolymer powder suitable for use in powder molding is disclosed. This copolymer powder has: (A) a density of 0.915 through 0.945 g/cm<3>; (B) a melt index of 1 through 80 g/10 min.; (C) a ratio of the high-load melt index under 21.6 kg to the low-load melt index under 2.16 kg of not more than 30; (D) a bulk density of 0.30 through 0.50; (E) an angle of repose of 25 DEG through 40 DEG , and; (F) a particle size distribution such that the 50% particle diameter of the powder is within the range of 230 to 350 microns and the particle diameter of at least 90% by weight of the total powder is within the range of 149 to 500 microns. This powder is in the form of a sphere, ellipsoid or the similar form and contains no substantial amount of the clear side, arris and thread-like or whisker- like portion, and is obtained by suspension polymerization of ethylene and alpha-olefin(s) in the presence of certain organometallic catalysts.
Description
SPECIFICATION
Ethylene-alpha-olefin copolymer powder for powder molding
The present invention relates to ethylene-alpha-olefin copolymer powder for powder molding. More
specifically, it relates to resin powder suitable for use in a rotational molding processes.
Polyethylene powder is processed by powder molding, typically rotational molding, fluidized bed coating,
sinter molding, powder coating on clothes for fusible interlining, electrostatic powder coating and other various powder coating methods. Polyethylene which can be employed in these processing methods
includes high-density polyethylene, medium-density polyethylene and low-density polyethylene. These three types of the polyethylene are widely and efficiently employed for various purposes depending upon their characteristics.
Of these three types of polyethylenes, medium-density polyethylene and low-density polyethylene are
generally produced in the form of pellets, since their production processes have been heretofore limited to a solution polymerization process and a high-pressure polymerization. As a result, in order to employ these types of polyethylene in powder molding, the pellets must be ground by means of mechanical grinding, low temperature grinding, chemical grinding and the like. However, the particle characteristics of the powder thus obtained are not satisfactory due to the facts that the powder has a low bulk density, a high angle of
repose, a wide particle size distribution and an ununiform particle form. Therefore, the rotational molding articles of which all or detailed portions are finely finished are difficult to obtain.
On the other hand, high-density polyethylene is generally produced by a slurry polymerization process and, therefore, is available in the form of powder. However, although the high-density polyethylene has good characteristics, such as stiffness, high temperature resistance, barrier properties and the like, it has disadvantages that the residual strain and residual stress are large due to the high crystallizability, the strain of large-sized molded articles obtained therefrom is larger than that obtained from medium-density
polyethylene and the impact resistance and E.S.C.R. (environmental stress cracking resistance) are low.
Furthermore, the powder characteristics of the high-density polyethylene obtained from a conventional
production process are not practically satisfactory for the reason that the particle size distribution of the
powder is generally broad, especially a large amount of fine particles is contained in the powder.
The present invention provides resin powder suitable for use in rotational molding and other powder processing processes, viz. ethylene-alpha-olefin copolymer powder having a medium density, a medium melt index and a low ratio of the high-load melt index (21.6 kg) to the low-load melt index (2.16 kg), both suitable for use in rotational molding, a relatively high bulk density, a low angle of repose, a narrow particle size distribution and a uniform particle shape in the form of a sphere, ellipsoid or other substantially rounded form.
In accordance with the present invention, there is provided ethylene-alpha-olefin copolymer powder for powder
(A) scid powder having a density of 0.915 through 0.945 g/cm3,
(B) said powder having a melt index of 1 through 80 gilO min.,
(C) said powder having a ratio of the high-load melt index under 21.6 kg to the low-load melt index under 2.16 kg of not more than 30,
(D) said powder having a bulk density of 0.30 through 0.50,
(E) said powder having an angle of repose of 25 through 40 , (F) said powder having a particle size distribution such that the 50% particle diameter of the powder is within the range of 230 to 350 microns and the particle diameter of at least 90% by weight of the total powder is within the range of 149 to 500 microns.
(G) said powder being in the form of substantially round particles i.e. a sphere, ellipsoid or similar form and containing no substantial amount of clear side, arris and thread-like or whisker-like portion, and
(H) said powder being obtained from suspension polymerization.
The present invention will be better understood from the description set forth below with reference to the accompanying drawings in which:
Figure 1 is an electron photomicrograph (100 x magnification) of the powder particles of the present invention, taken by using a scanning type electron microscope;
Figure2 is an electron photomicrograph (50 x magnification) of the powder particles obtained from the mechanical grinding of pellets of commercially available medium-density polyethylene, taken by using a scanning type electron microscope, and;
Figure 3 is a schematic view of a mold used in the detailed portion moldability test of various types of the powder of the Examples and Comparative Examples set forth hereinbelow.
The alpha-olefins copolymerized with ethylene in the production of the powder of the present invention include, for example, propylene, butene-1, isobutene, pentene-1, 4-methylpentene-1, hexene-1, heptene-1, octene-1 and the like. These alpha-olefins may be employed alone or any mixtures thereof.
The density of the ethylene-alpha-olefin copolymer of the present invention should be within the range or 0.915 to 0.945 g 'cm3, preferably 0.925 to 0.940 g/cm3. In a case where the density is more than 0.945 gtcm3, the strain (e.g. so-called warpage and sink-mark) in the powder molded articles unpreferably increases and, also, the fine finish of the detailed or intricate portions of the molded articles (which is hereinafter called the "fine finish of the detailed portions") become worse compared to the case in which the density is within the above-mentioned range. Furthermore, in physical properties, the impact resistance and E.S.C.R. decrease although the stiffness increases.Contrary to this, in a case where the density is less than 0.915 g/cm3, the decrease in the stiffness, the high temperature resistance, the oil resistance and the like becomes unpreferably large and it is relatively difficult to produce the powder having good characteristics by a suspension polymerization.
The melt index of the ethylene-alpha-olefin copolymer of the present invention should be within the range of 1 to 80 g/10 mins., preferably 2.5 to 30 g/10 mins. In a case where the melt index is more than 80 g/10 mins.
the strain and the fine finish of the detailed portions become worse compared to the case in which the melt index is within the above-mentioned range. Furthermore, the physical properties such as the impact resistance and E.S.C.R. are remarkably decreased. Contrary to this, in a case where the melt index is less than 1 g/10 mins., the powder particles are difficult to smoothly fuse with each other since the melt viscosity becomes large. Furthermore, if the molding temperature is raised to solve the above-mentioned problem, the resin is unpreferably degraded or a large amount of heat stabilizers is required.
The ratio of the high-load melt index (HMl) under 21.6 kg to the low-load melt index (LMI) under 2.16 kg of the ethylene-alpha-olefin copolymer should be not more than 30, preferably 23 or less. In a case where the ratio (HMI/LMI) is more than 30, the fluidizability or melt flow is not acceptable for the powder processing in which no substantial shearing force is present. Especially when the melt index is low, the lower the ratio is, the more preferable this powder is for the powder processing. Furthermore, as the ratio is lowered, the impact resistance generally increases. However, a copolymer powder having the ratio (HMI/LMI) of not more than 10 is relatively difficult to produce.
The bulk density of the ethylene-alpha-olefin copolymer powder of the present invention should be within the range of 0.30 to 0.50, preferably 0.35 to 0.45. In a case where the bulk density is more than 0.50, a copolymer powder having the above-mentioned desired powder characteristics other than the bulk density is difficult to produce. Contrary to this, in a case where the bulk density is less than 0.30, not only is the processability or workability not preferable, but also, the moldability of the detailed portions of articles to be molded becomes worse compared to the case in which the bulk density is not less than 0.30.
The angle of repose of the copolymer powder of the present invention should be within the range of 25 to 40 , preferably 25" to 35". If the angle of repose is more than 40 , the flowability of the powder unpreferably decreases and, therefore the fine finish of the detailed portions is not acceptable for practical use. Contrary to this, in a case where the angle of repose is less than 25 , the copolymer powder having the above-mentioned desired characteristics other than the angle of repose is difficult to produce.
The particle size distribution of the copolymer powder should be such that the 50% particle diameter of the powder is within the range of 230 to 350 microns, preferably 250 to 350 microns, and the particle diameter of at least 90% by weight of the total powder is within the range of 149 to 500 microns, preferably 210 to 420 microns. The term particle size distribution is determined by a sieve analysis method according to JIS (Japanese Industrial Standard)-K-0069 in which a sieve according to JIS-Z-8801 is used. By this sieve analysis method, a so-called cumulative distribution curve is obtained. The term "50% particle diameter" of the powder, used herein, is the diameter of the powder at the point of 50% of the cumulative distribution obtained from the above-mentioned cumulative distribution curve.The average diameter of the powder is represented by the 50% particle diameter.
As mentioned above, the copolymer powder of the present invention having a relatively large average particle diameter and a sharp particle size distribution has a good powder moldability, especially in the fine finish of the detailed portions of the molded articles. Contrary to this, in a case where the particle size distribution of the copolymer powder is out of the above-mentioned range, the powder moldability becomes unpreferably bad. For instance, the inside surface of the molded articles is not smooth, the thickness of the molded articles is not uniform and the fine finish of the detailed portions of the molded articles is not acceptable for practical use.
The copolymer powder particles of the present invention should be in the form of a sphere, ellipsoid or the similar form and contain no substantial amount of the clear side, arris and thread-like or whisker-like portion, as illustrated in Figure 1. Contrary to this, the powder particles obtained from the mechanical grinding of the pellets in a conventional manner contain substantial amounts of thread-like and whisker-like portions and are in the form of very complicated shapes like teared-off portions as illustrated in Figure 2. Furthermore, the powder particles obtained from a low temperature grinding of the pellets at a temperature of liquid nitrogen contain a relatively small amount of thread-like or string-like portions but clear sides and arrises are present in the powder particles.In a case where the shapes of the powder particles are very complicated, the flowability of the powder particles are not good and, therefore, the fine finish of the detailed portions becomes bad. Furthermore, since the grinding of the pellets consumes a large amount of energy and, also makes the working atmosphere worse due to the generation of noise and the use of refrigerants and solvents in any case, the production of the powder particles which requires the grinding step is not preferable.
The ethylene-alpha-olefin copolymer powder containing ethylene, as a major constituent, according to the present invention is preferably produced by a suspension polymerization forthe reasons that all the above-mentioned characteristics required in the copolymer powder of the present invention can be fulfilled and that the suspension polymerization is economically advantageous. The powder obtained by grinding the resin pellets derived from a solution polymerization and a high-pressure polymerization are not preferable in the present invention.
So long as the above-mentioned characteristics of the powder are fulfilled, the other monomers such as butadiene and, isoprene can be copolymerized in the copolymer powder of the present invention.
The ethylene-alpha-olefin copolymer powder containing, as a major constituent, ethylene according to the present invention can be produced, for example, in the following manner.
Ethylene is polymerized in the presence of alpha-olefin and a catalyst at room temperature through 1 00"C under a pressure such that the polymerization mixture is maintained in a suspended state. The catalysts used in the suspension polymerization of the ethylene-alpha-olefin copolymer include those comprising a hydrocarbon-soluble organomagnesium component and a transition metal compound or comprising a transition metal compound and an alumosiloxane.
The catalysts comprising a hydrocarbon-soluble organomagnesium component and a transition metal compound suitable for use in the production of the copolymer powder of the present invention include, for example, those which are disclosed in U.S. Patent Nos. 3,989,878; 4,004,071; 4,027,089; and 4,159,965.
These catalysts comprise a solid catalyst component (A) and an organometallic compound (B). The solid catalyst component (A) is a reaction product of the following compounds (i) and (ii) or compounds (i), (ii) and (iii).
(i) (a) A hydrocarbon-soluble compound represented by a general formula Ms,Mgl,Rp1 Rq2XrY5 wherein
cc, p, q, rand s each independently isO or a number greater than 0, 13 is 1 our a numbergreaterthan 1, p + q + r + s = ma + 2)), m is the valence of M, Mis a metal of the 1 st to 3rd groups of the Periodic Table,
R1 and R2 each independently is a hydrocarbon group having 1 to 20 carbon atoms,
X and Y each independently is OR3, oSiR4R5R6,NR7R8 or SR9 wherein R3, R4, R5, R6, R7 and R8 each independently is a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms and R9 is a hydrocarbon group having 1 to 20 carbon atoms;;
(b) a reaction product of the compound (i)(a) with a siloxane compound.
(ii) A titanium or vanadium compound containing at least one halogen atom.
(iii) The halide of Au, B, Si, Ge, Sn, Zn or Sb.
The organometallic compounds (B) includes compounds of a metal of the 1 st to 3rd groups of the Periodic
Table. Preferred organomet !lic compounds (B) are complexes containing an organoaluminum compound and an organomagnesium compound.
On the other hand, the catalysts based on alumosiloxanes and transition metal compounds suitable for use in the production of the copolymer powder of the present invention are those disclosed in, for example, U.S. Patent No 3,787,323, British Patent Nos. 1,502,964 and 1,502,963. These catalysts are those which are obtained from the reaction of (i) a compound of the formula,
R102HSiOA( Z2 wherein R'0 is a hydrocarbon group having 1 to 10 carbon atoms, and
Z is a halogen atom or a hydrocarbon group having 1 to 20 carbon atoms,
or any mixture thereof with (ii) a titanium or vanadium compound or complex containing at least one halogen atom per titanium or vanadium atom.
The copolymerization used in the production of the copolymer powder of the present invention can be carried out in the same manner as in an olefin polymerization process in which a conventional Ziegler type catalyst is used. The solvents used in the copolymerization include, for example, aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, kerosine and the like, alicyclic solvents such as cyclohexane, methylcyclohexane and the like, aromatic hydrocarbons such as benzene, toluene, xylene and the like.
Although the addition amount of the comonomer (i.e. alpha-olefins), can be widely changed depending upon, for example, the type of the alpha-olefins, the polymerization temperature and the partial pressure of the ethylene in a reactor, approximately 0.05 through 20 mol, preferably 0.10 through 5 mol of the alpha-olefin, per 1 mol of the ethylene, are generally fed to the reactor. Thus, copolymers having an ethylene content of 70 mol /O or more are generally obtained. The reaction temperature is preferably within the range of room temperature to 100C, more preferably, 50 to 90-C.The polymerization reaction is preferably carried out under pressure, generally ambient pressure to 50 kgcm2, preferably 2 to 20 kg!cm2. The molecular weight of the copolymer can be effectively controlled by the presence of hydrogen in the reaction system.
The ethylene-alpha-olefin copolymer powder obtained from the above-mentioned copolymerization process may optionally be subjected to a post-treatment step including a mechanical attrition treatment and.or a sieving operation. The mechanical attrition treatment can be conducted by using a high-speed fluidization mixer, such as a Henschel mixer, and various grinding machines.
The ethylene-alpha-olefin copolymer powder of the present invention is preferable for use in a powder molding process. As is well-known, the powder molding process is one of the plastic molding processes in which resin powder particles are contacted with a heated mold to fuse together, followed by cooling, wherein the molded articles are obtained. Various powder molding processes are known, which are classified depending upon the movement of the mold and the heating method. For instance, the powder molding processes include a Engel process, a Hayashi process, a Hysler process, a rock and roll process, a biaxial rotational molding process and the like, and also, include a powder coating process, such as a steel pipe coating, in which powder particles are coated on a heated substrate while rotating the substrate.
Although the ethylene-alpha-olefin copolymer powder of the present invention can be used in any of the conventional powder molding processes, including the above-mentioned processes, it is especially suitable for use in rotational molding processes, including a rock and roll process, a Hysler process and a biaxial rotational molding process, in which a mold or substrate is rotated during molding, and a powder coating process in which a substrate is rotated during coating.
In the case where the powder molding is carried out by using the copolymer powder of the present invention,the powder particles flow smoothly and the fusion of the particles occurs smoothly. As a result, the inside and outside surfaces of the molded articles are smoothly and finely finished, the nonuniform sections of the molded articles are minimized so that the thickness of the parts become uniform and the strain (e.g. warpage and sink-mark) of the molded articles is eliminated to produce molded articles having good dimensional accuracy.
Especially when the copolymer powder of the present invention is used, the fine finish of the detailed portions of the rotational molded articles is greatly improved compared to the conventional resin powders.
For instance, in the detailed portions, such as sharp corners of the conventionally molded articles, large or small depressed holes, pinholes or bridging are generated. Contrary to this, in the case where the copolymer powder of the present invention is used, the surface profile of a mold is faithfully reproduced in the surface of the molded article and, therefore, a fine finish is obtained. As a result, according to the present invention, molded articles having fine thread or sharp corners, which have been difficult to mold by powder molding, can be formed in a powder molding process by using the copolymer powder of the present invention.
Furthermore, molded articles having a long projection and a narrow cross sectional area are not advantageously prepared by a conventional rotational molding process due to the fact that the powder particles cannot cover all areas of the inside surface of the mold. Contrary to this, such molded articles can be molded by using the copolymer powder of the present invention. In addition, according to the present invention, engraved fine patterns can be imparted to the surface of molded articles and emboss processing can be applied to molded articles for ornamental purposes. As mentioned above, by the use of the copolymer powder of the present invention, the freedom of the design of molded articles is greatly broadened and additional value is remarkably imparted to molded articles.
The molded articles derived from the ethylene-alpha-olefin copolymer powder of the present invention have excellent physical properties, especially in a balance of the impact resistance and the other physical properties, and also, in E.S.C.R. Furthermore, good foamed products can be molded by adding chemical foaming agents to the copolymer powder of the present invention.
It should be noted that not only single-layer molded articles, but also, plural-layer molded articles can be satisfactorily molded by using the copolymer powder of the present invention, and also, that-sandwitch construction molded articles, in which a foamed layer is sandwitched by non-foamed layers, can be satisfactorily formed by using the copolymer powder of the present invention.
The ethylene-alpha-olefin copolymer powder of the present invention can contain, when it is used, various conventional additives, such as stabilizers, anti-oxidants, ultraviolet absorbing agent, antistic agents, lubricants, plasticizers, pigments, inorganic or organic fillers, fibrous reinforcing materials, fire retardants, mold releasing agents and the like in a conventinal manner In addition, petroleum resins, waxes, liquid rubbers, powder rubbers and other powder polymers can be added to the copolymer powder of the present invention in such as amount that the characteristics of the copolymer powder of the present invention are not impaired.
The present invention will now be specifically illustrated by, but is by no means limited to, the Examples set forth below.
The physical properties defining the copolymer powder of the present invention were determined according to the following methods.
Density ASTM D 1505
Melt Index : ASTM D1238
Bulk Density ASTM D 1895
Angle of Repose the drop-and-fill
method
Particle Size Destribution : JIS K 0069
Synthesis of solid catalyst
The solid catalysts used in the Examples and Comparative Examples set forth below were synthesized in a 10 liter stainless steel autoclove as follows.
(1) Solid Catalyst A
0.30 mol of titanium compound having a composition ofTi(O n-C4Hg)CI3 and 0.30 mol of alumosiloxane having a composition of Al(OSiH-CH3-C2Hs3(C2H5)CI were charged, together with 6 liters of hexane, into the autoclave. The mixture was allowed to react at a temperature of 70 C for 5 hours. The reaction mixture was filtered, whereby a solid catalyst was isolated. The solid catalyst thus obtained was washed with hexane until free halogen was not detected in the washed hexane. This catalyst is referred to as the solid catalyst A hereinbelow.
(2) Solid Catalyst B 0.20 mol of a reaction product of (C2H5)(n-C4H9)Mg and hydromethyl polysiloxane having a viscosity of 30 centistrokes in a ratio of Si Mg = 1.5/1.0, and 0.24 mol of titanium tetrachloride were charged, together with 6 liters of hexane, into the autoclave. The mixture was allowed to react at a temperature of -10 C for 3 hours.
The reaction mixture was subjected to the post-treatment described in the synthesis of the solid catalyst A whereby a solid catalyst was obtained. This catalyst is referred to as the solid catalyst B hereinbelow.
(3) Solid Catalyst C
0.20 mol of a reaction proudct of (iso-C4Hg)(n-C4Hg)Mg and a tetramer of methylhydroxy siloxane in a ratio of SiiMg = 1.0 1.0, and 0.20 mol of titanium tetrachloride were charged, together with 6 liters of hexane, into the autoclave. The mixture was allowed to react at a temperature of -20 C for 4 hours. The reaction mixture was treated in the same manner as in the case of the solid catalyst A, whereby a solid catalyst was obtained. This catalyst is referred to as the solid catalyst C hereinbelow.
(4) Solid Catalyst D 200 g of Mg(OC2H5)2, 3 liters of TiC135-(O n-C4Hg)05 and 3 liters of hexane were charged into the autoclave, and allowed to react at a temperature of 140"C for 2 hours. The reaction product was treated in the same manner as in the case of the solid catalyst A. Thus, a solid catalyst was obtained. This catalyst is referred to as the solid catalyst D hereinbelow.
(5) Solid Catalyst E The reaction and the post-treatment in the case of the solid catalyst D were repeated, except that titanium tetrachloride was used as a titanium compound. Thus, a solid catalyst was obtained. This catalyst is referred to as the solid catalyst E hereinbelow.
Preparation of Ethylene-Alpha-Olefin Copolymer Powder
Various kinds of ethylene-alpha-olefin copolymer powder were prepared in a manner as set forth in the following Examples and Comparative Examples. The characteristics of the powder particles thus prepared are listed in Table 1 below.
Example 1
A copolymer was prepared by a continuous polymerization process in a 200 liter stainless steel reactor.
While the reactor temperature was maintained at a temperature of 80"C, the polymerization reaction was carried out by adding, as a catalyst mixture, 1.1 g Hr of the solid catalyst A, 60 m molHr of alumosiloxane having a composition of Al(OSiH-CH3-C2H5)(C2H5)CI and 7.5 m moliHr of n-butyl ortho-titanate to the reactor, and also, adding, to the reactor, 30 6 Hr of hexane, 2.16 Hr of butene-1 as an alpha-olefin and ethylene containing 0.300 of hydrogen in an amount sufficient to yield 10 to 12kg hr of the copolymer.
Example 2
The polymerization reaction of Example 1 was repeated, except that 0.15 g Hr of the solid catalyst B and 6 m mol Hrto triethyl aluminum were employed, as a catalyst, and that 7.8 f Hr of hexene-1, as an alpha-olefin, and ethylene containing 0.6% of hydrogen were employed.
Example 3
The polymerization reaction of Example 2 was repeated, except that the reaction temperature was 75"C, and 0.21 g Hr of the solid catalyst B and 15 m mol Hroftriethyl aluminum were employed as a catalyst mixture, and that 3.06 Hr of butene-1 as an alpha-olefin and ethylene containing 0.7% of hydrogen were employed. The resultant copolymer powder was subjected to a high speed fluidized mixing treatment by using a Henschel mixer at a temperature of 70eC for 1 minute.
Example 4
The polymerization was carried out under the same conditions as in Example 1, except that the polymerization temperature was 85-C and that 3.7 6/Hr of 4-methyl-pentene-1, as an alpha-olefin, and ethylene containing 0.3% of hydrogen were employed.
Example 5
The polymerization was carried out under the same conditions as in Example 3, except that the polymerization temperature was 85"C and that 0.20 g/Hr of the solid catalyst C and 6 m mol/Hr of diethyl aluminum hydride, as a catalyst mixture, and 2.8 HHr of butene-1, as an alpha-olefin, and ethylene containing 0.6% of hydrogen were employed.
Example 6
The polymerization was carried out under the same conditions as in Example 1, except that the polymerization temperature was 75"C and that 30 t/Hr of pentane, as a polymerization medium, 2.5 lHr of butene-1,as an alpha-olefin, and ethylene containing 0.3% of hydrogen were employed.
Example 7
The polymerization was carried out in the same manner as in Example 1, except that the polymerization temperature was 70 C and that 30 (lHr of butane, as a polymerization medium, 3.0 (/H r of butene-1,as an alpha-olefin, and ethylene containing 0.4% of hydrogen were employed. The resultant powder was subjected to a high speed fluidized mixing treatment in a Henschel mixer at a temperature of 70 C for 1 minute.
Comparative Example 1
The polymerization was carried out in the same manner as in Example 1, except that 1.5 gZHr of the solid catalyst D and 30 m mol Hr of triethyl aluminum, as a catalyst mixture, 2.5 ('Hr of butene-1, as an alpha-olefin, and ethylene containing 0.8% of hydrogen were employed.
Comparative Example 2
The polymerization was carried out underthe same conditions as in Comparative Example 1, except that the reaction temperature was 750C, and that 2.9 fiHr of butene-1 and ethylene containing 1.0% of Hydrogen were employed.
Comparative Example 3
A copolymer was prepared by a continuous polymerization process in a 200 liter stainless steel reactor.
While the reactor temperature was maintained at a temperature of 80"C, the polymerization was carried out by adding, as a catalyst mixture, 0.9 gHr of the catalyst E and 40 m mol. Hr of ethyl aluminum ethoxide having a composition of Al(C2H5)2.7 (OC2H5)0.3 to the reactor, and also, adding, to the reactor, 60 (/her of hexane, 1.6( Hr of butene-1, as an alpha-olefin, and ethylene containing 0.3% of hydrogen in an amount sufficient to yield 6 to 7 kg Hr of the copolymer. The copolymer powder thus obtained was subjected to a high speed fluidized mixing treatment at a temperature of 85C for 7 minutes.
Comparative Example 4
The polymerization was carried out under the same conditions as in Comparative Example 2, except that 0.8 l Hr of hexene-1, as an alpha-olefin, and ethylene containing 1.0% of hydrogen were employed.
Comparative Example 5
The polymerization was carried out under the same conditions as in Comparative Example 1, except that 1.2 g Hr of the solid catalyst E and 15 m mol Hr oftriethyl aluminum, as a catalyst mixture, and 2.3 ( Hr of butene-1, as an alpha-olefin, and ethylene containing 1.1% of hydrogen were employed.
Comparative Example 6
Commercially available high-density polyethylene powder derived from suspension polymerization (Suntec R 340 P manufactured by Asahi Kasei Kogyo Kabushiki Kaisha) was used, as a sample of
Comparative Example 6, in the evaluation test described below.
Comparative Example 7
Commercially available mechanically ground powder of medium-density polyethylene (Neozex 4060 P manufactured by Mitsui Sekiyu Kagaku Kogyo Kabushiki Kaisha) was used, as a sample of Comparative
Example 7, in the evaluation test described below.
Comparative Example 8
Commercially available mechanically ground powder of medium-density polyethylene (Neozex 4330 P manufactured by Mitsui Sekiyu Kagaku Kogyo Kabushiki Kaisha) was used, as a sample of Comparative
Example 8, in the evaluation test described below.
Performance Evaluation Test ofEth ylene-Alpha-Olefin Copolymer Powder
The rotational molding characteristics of various kinds of the ethylene-alpha-olefin copolymer powder of the above-mentioned Examples and Comparative Examples were evaluated in the manners as described below. The results are shown in Table 1 below.
The physical properties of typical samples of the ethylene-alpha-olefin copolymer powder of the above-mentioned Examples and Comparative Examples were evaluated by using test pieces obtained from a press molding. The results are shown in Table 2 below.
1) A 500 liter tank lorry was molded by a rock and roll process.
Molding Conditions
Mold Made of a 2 mm thick sheet metal Weight of Articles: 20kg Heating : Propane gas burner, 20 minutes
Cooling : Fan Cooling, 15 minutes
Evaluation Standard
a) Defoaming : Evaluation of fusing ability of the powder particles.
+ : No foam present in molded article.
t : Some small-sized foam present in molded article - : Large-and small-sized foam present in entire surface of molded article.
b) Molding Strain: Evaluation of dimensional accuracy of the molded article
+: Overall strain and local warpage and sink-mark not observed in the molded article.
+: Local warpage and sink-mark observed, although overall strain not observed.
Both overall distortion and local warpage and sink-mark observed.
c) Internal Surface Smoothness: Evaluation of uniformity of the internal surface of the molded article.
+ : Internal surface entirely smooth and uniform.
I : Small amount of grannular structure locally present in internal surface of molded article.
Large amount of grannular structure present in entire surface of internal surface of molded article
and internal surfce nervy.
d) Thickness Uniformity: Evaluation of the uniformity of the section thickness of the molded article.
+ : Thickness of side plane of molded article within 4.2 + 0.4 mm.
Thickness of side plane of molded article within 4.2 1 0.8 mm.
Thickness of side plane of molded article outside range of 4.2 + 0.8 mm.
e) Thread Moldability: Evaluation of the fine finish of the detailed portion of the molded article.
(Thread dimension: JIS internal thread 56 M 5.5 P)
+: Thread portions faithfully reproduced, compared to mold, in molded article.
+: Small amount of small-sized holes present in top of thread of molded article.
- : Top of thread of molded article not sharply molded.
2) A mold, as illustrated in Figure 3, for testing the fine finish of the detailed portions was molded by a biaxial rotational molding process (i.e. by a McNeil roto-molder). This mold 10 was provided with projected hollow cylinders 11, 12, 13 and 14 having diameters of 10.2 mm, 19.6 mm, 31.0 mmQ and 39.0 memo, respectively and each having a length of 97 mm, for evaluating the flow ability of the powder particles into the smallest two cylinders compared to the largest two cylinders. The mold 10 was also provided with a plurality of sharp corners 15, for evaluating the reproducibility of the hold. The length a and the width b of the mold 10 are 268.5 mm and 367 mm, respectively.
Mold Conditions
Mold Made of cast aluminum having a thickness of 2 mm Weight of Articles: : 600g Heating Hot air having a temperature of 300"C, 15 minutes
Cooling Fan cooling 10 minutes, water cooling 2 minutes.
Evaluation Standard
+: Sharp corners 15 clearly molded and projected portions 11 and 12 uniformly molded.
+: Nicks and scratches present to slight extent in molded sharp corners 15, and small holes or
pinholes present in top of molded projected portions 11 and 12, although projected portions 11 and
12 are molded.
Nicks and scratches present in molded sharp corners 15, and projected portion 11 not completely
molded and small holes present in top of molded projected portion 12, although portion 12 can be
molded.
TABLE 1
Density Melt HMI Bulk Angle 50% Particle Size Distribution Defoam- Mold- Internal Thick- Thread Fine
Index Dens- of Particle (%) ing ing Surface ness Molda- Finish
No. IMI ity Repose Diameter 590 420 297 149 210 149 149 Strain Smooth- Ununi- bility of (g/cm ) (microns) (microns) ness fromity Detailed on on on on on pass Portion
Example 1 0.939 3 21 0.42 31 305 t* 1.8 55.7 39.8 2.0 0.7 + + + + + + " 0.939 3 21 0.34 33 260 t 0.6 30.1 55.0 10.0 4.4 + + + + + +
Comparative
Example 1 0.939 3 26 0.26 37 b2.2 16.2 34.6 27.2 12.2 8.1 # + # # # #
Example 3 0.939 3 21 0.35 27 250 t t 30.3 57.6 10.1 2.0 + + + + ,+ +
Comparative
Example 2 0.939 3 27 0.31 41 260 t 3.9 37.8 31.0 15.2 12.1 - + # - # " 3 0.939 3 27 0.38 42 160 t 1.7 7.4 22.9 21.0 46.8 # + - - # " 4 0.939 3 24 0.29 36 40 12.8 31.4 37.8 13.3 3.4 1.3 # + - # # #
Example 4 0.939 7 21 0.40 31 305 t 1.2 55.9 40.0 2.4 0.5 + + + + + + " 5 0.944 7 24 0.30 39 340 1.9 27.0 35.8 21.3 9.2 4.8 + + + + + + " 6 0.930 3 20 0.35 28 260 t t 29.3 56.6 12.1 2.0 + + + + + + " 7 0.922 3 22 0.35 32 305 t 2.5 51.0 42.4 2.9 1.2 + + + + + +
Comparative
Example 5 0.939 3 35 0.35 33 260 t 1.2 31.4 54.5 11.0 1.9 + + # + # # " 6 0.953 7 31 0.39 34 230 0.6 3.1 19.4 44.8 17.0 15.1 + # + + # # " 7 0.942 6.5 22 0.36 43 220 3.1 7.8 20.2 28.2 22.6 18.1 + + + + # # " 8 0.943 3.5 22 0.35 44 210 1.0 9.2 21.2 24.7 20.5 23.5 + + # # - * t = traces TABLE 2
(1) (2) (3) (4) (5)
Tensile Izod Tensile
Yield Elongation Impact Impact ESCR
No. Strength at Break Strength Strength (kg.cm/cm (kg/cm2) (%) with notch) (kg.cmlcm2) (Hr)
Example 1 170 300 No break 180 420 4 4 173 300 42 160 340
5 5 185 300 15 100 36
t 6 130 300 No Break 210 500 7 7 105 300 No Break 240 500
Comparative
Example 5 168 300 23 160 350 " 6 230 300 5 76 4 (1) ASTM D 638
(2) ASTM D 638
(3) ASTM D 256
(4) ASTMD1822 (5) ASTM Dl 693 (3mm Thick Test Piece, 50 C, 10% Noigen*) * Polyethylene nonylphenyl ether
Claims (11)
1. Ethylene-alpha-olefin copolymer powder for powder molding containing, as a major constituent, ethylene,
(A) said powder having a density of 0.915 through 0.945 g/cm3, (B) said powder having a melt index of 1 through 80 g/10 min.,
(C) said powder having a ratio of the high-load melt index under 21.6 kg to the low-load melt index under 2.16 kg of not more than 30,
(D) said powder having a bulk density of 0.30 through 0.50,
(E) said powder having an angle of repose of 25 through 40 , (F) said powder having a particle size distribution such that the 50% particle diameter of the powder is within the range of 230 to 350 microns and the particle diameter of at least 90% by weight of the total powder is within the range of 149 to 500 microns,
(G) said powder being in the form of a sphere, ellipsoid or the similar form and containing no substantial amount of the clear side, arris and thread-like or whisker-like portion, and
(H) said powder being obtained from suspension polymerization.
2. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein said copolymer is selected from the group consisting of ethylene-1-butene copolymer, ethylene-hexene copolymer and ethylene-4methyl pentene-1 copolymer.
3. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein the density of the powder is within the range of 0.925 to 0.940 g,cm3.
4. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein the melt index of the powder is within the range of 2.5 to 30 gil 0 min.
5. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein the ratio of the low-load melt index under 2.16 kg to the high-load melt index under 21.6 kg is not more than 23.
6. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein the bulk density of the powder is within the range of 0.34 to 0.45.
7. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein the angle of repose is within the range of 25 to 35".
8. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein said powder has such particle size distribution that the 50% particle diameter is within the range of 250 to 350 microns and the particle diameter of at least 70% by weight of the total powder is within the range of 210 to 420 microns.
9. Ethylene-alpha-olefin copolymer powder as claimed in claim 1, wherein said copolymer is produced by polymerizing ethylene in the presence of alpha-olefin other than ethylene and a catalyst at a temperature of room temperature to 1000C under pressure where the polymerization mixture is maintained in a suspended state, said catalyst comprising a solid component (A) and an organometal component (B), the solid component (A) being produced by reacting a hydrocarbon-soluble organomagnesium component (i-a) of the formula Mα;MgssRpRqXrYs wherein
a, p, q, rand s each independently isO or a number greater than 0,
ss is 1 ora numbergreaterthan 1, p + q + r + s = ma + 2p,
m is the valence of M, Mis a metal ofthe 1st to 3rd groups ofthe Periodic Table,
R' and R2 each independently is a hydrocarbon group having 1 to 20 carbon atoms,
X and Y each independently is OR3, oSiR4R5R6 NR7R8 or SR9 wherein R3, R4, R5, R6,R7 and R8 each independently is a hydrogen atom our a hydrocarbon group having 1 to 10 carbon atoms and R9 is a hydrocarbon group having 1 to 20 carbon atoms;;
or (i-b) a reaction product ofthe hydrocarbon-soluble organomagnesium compound (i-a) with a siloxane compound; (ii) a titanium or vanadium compound having at least one halogen atom; and (iii) a halid of A(,
B, Si, Ge, Sn, Zn or Sb, or said catalyst being produced by reacting (iv) at least one compound of the formula Rl 2HSiOAZ Z wherein
R10 is a hydrocarbon group having 1 to 10 carbon atoms,
Z is a hydrocarbon group having 1 to 20 carbon atoms, with (v) a titanium or vanadium compound or complex having at least one halogen atom.
10. An ethylene-alpha-olefin copolymer powder having ethylene as a major constituent, said powder having been obtained by suspension polymerization and said powder being in the form of substantially rounded particles and having
(A) a density of 0.915 to 0.945 g!cm3,
(B) a melt index of 1 to 80 g/10 min.,
(C) a ratio of the high-load melt index under 21.6 kg load to the low-load melt index under 2.16 kg load of
not more than 30:1, (D) a bulk density of 0.30 to 0.50,
(E) an angle of repose of 25 to 40 , (F) a particle size distribution such that the 50% particle diameter of the powder is within the range of 230 to 350 microns and the particle diameter of at least 90% by weight of the total powder is within the range of 149 to 500 microns.
11. An ethylene-alpha-olefin copolymer according to claim 10 substantially as described in any one of the Examples.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11522479A JPS5641213A (en) | 1979-09-10 | 1979-09-10 | Ethylene-alpha-olefin copolymer powder for powder molding |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2058092A true GB2058092A (en) | 1981-04-08 |
Family
ID=14657424
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB27341A Withdrawn GB2058092A (en) | 1979-09-10 | 1980-08-22 | Ethylene-alpha-olefin copolymer powder for powder molding |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS5641213A (en) |
| BE (1) | BE885151A (en) |
| CA (1) | CA1131398A (en) |
| DE (1) | DE3033639A1 (en) |
| FR (1) | FR2464970B1 (en) |
| GB (1) | GB2058092A (en) |
| IT (1) | IT1195031B (en) |
| NL (1) | NL8004923A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0087204A1 (en) * | 1982-02-20 | 1983-08-31 | Stamicarbon B.V. | Polymer powder compositions, particularly polyethylene powder compositions, and objects to be made and made thereof |
| EP0209104A1 (en) * | 1985-07-15 | 1987-01-21 | QUANTUM CHEMICAL CORPORATION (a Virginia corp.) | Intermetallic compound |
| EP0323719A2 (en) * | 1987-12-14 | 1989-07-12 | Sumitomo Chemical Company, Limited | Process for producing pre-expanded particles of a polyolefin |
| US6573314B1 (en) | 1998-12-11 | 2003-06-03 | Borealis Technology Oy | Method of producing pelletized polyolefin |
| EP1428841A1 (en) * | 2002-12-12 | 2004-06-16 | ATOFINA Research | Rotomoulded articles with dimensional stability |
| US6894109B1 (en) | 1998-12-11 | 2005-05-17 | Borealis Technology Oy | Method of producing pelletized polyolefin |
| WO2012010476A1 (en) * | 2010-07-22 | 2012-01-26 | Ineos Europe Ag | Polymer composition |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2533540B2 (en) * | 1987-05-28 | 1996-09-11 | 宇部興産 株式会社 | Adhesive powder polyethylene |
| JP2509948Y2 (en) * | 1990-05-25 | 1996-09-04 | 敬 高橋 | Box-shaped shell-type aquarium with solar heat storage function |
| JP3010516B2 (en) * | 1991-12-09 | 2000-02-21 | 大日本インキ化学工業株式会社 | Method for producing modified propylene polymer |
| CN104098727B (en) * | 2013-04-03 | 2016-11-16 | 中国石油天然气股份有限公司 | A kind of high-density polyethylene resin and preparation thereof and application |
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|---|---|---|---|---|
| GB1498852A (en) * | 1974-04-30 | 1978-01-25 | Asahi Chemical Ind | Catalyst and method for polymerizing ethylene and propylene |
| JPS5236789B2 (en) * | 1974-05-07 | 1977-09-17 | ||
| JPS5222794B2 (en) * | 1974-05-16 | 1977-06-20 | ||
| CA1062692A (en) * | 1974-05-25 | 1979-09-18 | Itsuho Aishima | Process for polymerizing ethylene |
| GB1543908A (en) * | 1975-03-07 | 1979-04-11 | Ici Ltd | Ethylene polymers |
| JPS5236788A (en) * | 1975-09-18 | 1977-03-22 | Matsushita Electric Ind Co Ltd | Porcelain composition for humidity sensig resister |
| JPS5236789A (en) * | 1975-09-18 | 1977-03-22 | Matsushita Electric Ind Co Ltd | Porcelain composition for humidity sensing resister |
| JPS5340696A (en) * | 1976-09-28 | 1978-04-13 | Asahi Chem Ind Co Ltd | Olefin polymerization catalyst |
| DE2801541A1 (en) * | 1978-01-14 | 1979-07-19 | Hoechst Ag | AETHYLENE COPOLYMERS AND THEIR USE FOR THE PRODUCTION OF FILMS |
-
1979
- 1979-09-10 JP JP11522479A patent/JPS5641213A/en active Pending
-
1980
- 1980-08-18 CA CA358,475A patent/CA1131398A/en not_active Expired
- 1980-08-22 GB GB27341A patent/GB2058092A/en not_active Withdrawn
- 1980-08-29 NL NL8004923A patent/NL8004923A/en unknown
- 1980-09-06 DE DE19803033639 patent/DE3033639A1/en not_active Ceased
- 1980-09-09 FR FR8019441A patent/FR2464970B1/en not_active Expired
- 1980-09-09 BE BE0/202041A patent/BE885151A/en not_active IP Right Cessation
- 1980-09-10 IT IT24569/80A patent/IT1195031B/en active
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0087204A1 (en) * | 1982-02-20 | 1983-08-31 | Stamicarbon B.V. | Polymer powder compositions, particularly polyethylene powder compositions, and objects to be made and made thereof |
| US4533696A (en) * | 1982-02-20 | 1985-08-06 | Stamicarbon B.V. | Polymer powder compositions, particularly polyethylene powder compositions and objects to be made and made thereof |
| EP0209104A1 (en) * | 1985-07-15 | 1987-01-21 | QUANTUM CHEMICAL CORPORATION (a Virginia corp.) | Intermetallic compound |
| EP0323719A2 (en) * | 1987-12-14 | 1989-07-12 | Sumitomo Chemical Company, Limited | Process for producing pre-expanded particles of a polyolefin |
| EP0323719A3 (en) * | 1987-12-14 | 1990-10-24 | Sumitomo Chemical Company, Limited | Process for producing pre-expanded particles of a polyolefin |
| US6573314B1 (en) | 1998-12-11 | 2003-06-03 | Borealis Technology Oy | Method of producing pelletized polyolefin |
| US6894109B1 (en) | 1998-12-11 | 2005-05-17 | Borealis Technology Oy | Method of producing pelletized polyolefin |
| EP1428841A1 (en) * | 2002-12-12 | 2004-06-16 | ATOFINA Research | Rotomoulded articles with dimensional stability |
| WO2012010476A1 (en) * | 2010-07-22 | 2012-01-26 | Ineos Europe Ag | Polymer composition |
| US9115280B2 (en) | 2010-07-22 | 2015-08-25 | Ineos Europe Ag | Polymer composition |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5641213A (en) | 1981-04-17 |
| FR2464970A1 (en) | 1981-03-20 |
| FR2464970B1 (en) | 1985-11-22 |
| IT1195031B (en) | 1988-09-28 |
| NL8004923A (en) | 1981-03-12 |
| CA1131398A (en) | 1982-09-07 |
| IT8024569A0 (en) | 1980-09-10 |
| BE885151A (en) | 1981-03-09 |
| DE3033639A1 (en) | 1981-03-19 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |