JPH0321651A - Ultra-high molecule polyolefin-based molecular-orientated molding - Google Patents

Abstract

PURPOSE:To obtain the subject molding excellent in long-term heat stability and weather resistance while maintaining original tensile strength, etc., by blending an ultra-high molecule polyolefin with a specified amount of an organic phosphite-based stabilizer, etc. CONSTITUTION:With (A) 100 pts.wt. ultra-high molecule polyolefin having >=5dl/g intrinsic viscosity, (B) 0.005-5 pts.wt, preferably 0.05-0.2 pts.wt. organic phosphite-based stabilizer (e.g. triphenylphosphite), (C) 0.005-5 pts.wt., preferably 0.05-0.2 pts.wt. hindered amine-based stabilizer [e.g. bis(2,2,6,6-tetramethyl-4- piperidyl)sebacate] and, as necessary, (D) 0.005-5 pts.wt., preferably 0.05-0.5 pts.wt. metal salt of a higher fatty acid (e.g. magnesium strearate) are blended.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to an ultra-high molecular weight polyolefin-based molecularly oriented shaped body having excellent long-term heat stability and weather resistance.

Technical background of the invention and its problems It is already known that a molecularly oriented or shaped body with high tensile strength and high tensile modulus can be obtained by forming an ultra-high molecular weight polyolefin into a fiber, tape, etc. and then stretching it. It has become. For example, JP-A-56-15408 discloses a method of spinning a seed solution of ultra-high molecular weight polyethylene and then drawing the resulting filament.

Further, JP-A-59-130313 discloses a method in which a dredged material obtained by melt-kneading ultra-high molecular weight polyethylene and wax is extruded, and then the mixed material is cooled, solidified, and stretched. Furthermore, JP-A-59-187614
The publication discloses a method in which the molten mixture is extruded and then passed through a draft, and then the molten mixture is cooled, solidified, and stretched.

Molecularly oriented or shaped bodies such as fibers and tapes made of ultra-high molecular weight polyolefins have high tensile strength and high tensile ampacity, so they are used in applications that require particularly high quality. It may be used for a long period of time in a high temperature atmosphere. However, since molecularly oriented molded products made of ultra-high molecular weight polyolefins are essentially polyolefins, they easily deteriorate at high temperatures and have problems with long-term heat resistance stability, such as reduced tensile strength and tensile modulus. Ta. As a method for preventing such thermal deterioration of the ultra-high molecular weight polyolefin molecularly oriented molded article, there is a method of adding a heat-resistant stabilizer to the ultra-high molecular weight polyolefin. However, ultra-high molecular weight polyolefin molecularly oriented shapes are manufactured through a process in which the diluent is eluted using a solvent such as decalin as a heating medium during stretching of the ultra-high molecular weight polyolefin. At the same time, this stabilizer is eluted into the solvent, so that thermal deterioration of the ultra-high molecular weight polyolefin molecularly oriented molded article could not be sufficiently prevented.

In addition, conventional ultra-high molecular weight polyolefin molecularly oriented shaped bodies have the problem of not only poor long-term heat resistance stability as described above but also poor weather resistance.

Purpose of the Invention The present invention aims to solve the above-mentioned problems, and aims to provide ultra-high molecular weight polyolefin with long-term heat resistance stability that does not impair the inherent tensile strength, tensile modulus, etc. Another object of the present invention is to provide an ultra-high molecular weight polyolefin-based molecularly oriented molded article having excellent dust resistance.

Summary of the Invention The first ultra-high molecular weight polyolefin-based molecularly oriented molded article according to the present invention comprises: (A) an ultra-high molecular weight polyolefin; (B) an organic phosphite stabilizer: (A) 100 parts by weight of an ultra-high molecular weight polyolefin. (C) hindered amine stabilizer: (A) 0.005 to 5 parts by weight per 100 parts by weight of ultra-high molecular weight polyolefin.

Further, the second ultra-high molecular weight polyolefin-based molecularly oriented or shaped body according to the present invention includes: (A) ultra-high molecular weight polyolefin; (B) an organic phosphite-based stabilizer: (A) for 100 ffin parts of ultra-high molecular weight polyolefin; , 0.005~
(C) hindered amine stabilizer: (A) 0.005 to 5 parts by weight per 100 parts by weight of ultra-high molecular weight polyolefin; (D) metal salt of higher fatty acid; (A) ultra-high molecular weight It is characterized by containing 0.005 to 5 parts by weight per 100 parts by weight of polyolefin.

The ultra-high molecular weight polyolefin-based molecularly oriented form according to the present invention comprises an ultra-high molecular weight polyolefin (A), a specific amount of the stabilizers (B) and (C), or a specific amount of the stabilizer (B), ( C) and CD), it has excellent long-term heat resistance stability and iJ weatherability, and maintains high tensile strength and high tensile modulus.

DETAILED DESCRIPTION OF THE INVENTION The ultra-high molecular weight polyolefin molecularly oriented molded article according to the present invention will be specifically described below.

The ultra-high molecular weight polyolefin-based molecularly oriented molded article according to the present invention comprises an ultra-high molecular weight polyolefin (A), a specific amount of the stabilizers (B) and (C), or a specific amount of the stabilizer (B), ( C) and (D).

The molecularly oriented ultra-high molecular weight polyolefin composition according to the present invention is produced by adding a diluent to the ultra-high molecular weight polyolefin composition containing the above-mentioned portions (A), (B), (C) and (D). be able to.

First, the components that make up this ultra-high molecular weight polyolefin material will be explained.

Ultra-high molecular weight polyolefin (A) The ultra-high molecular weight polyolefin (A), which is one component of the ultra-high molecular weight polyolefin composition, includes, for example, ethylene, propylene, l-butene, i-pentene, {-hexene, t
-Octene, i-decene, 1-dodecene, 4-methyl-
It consists of a homopolymer or copolymer of α-olefins such as 1-bentene and 3-methyl-1-pentene. Among these, ethylene homopolymer or ethylene and other α
-Olefins such as t-butene, i-pentene, i
-octene, 4-methyl-1-pentene, etc., and a copolymer containing ethylene as a main component is particularly preferred.

135 of the ultra-high molecular weight polyolefin (A) as described above
The intrinsic viscosity [η] measured in decalin solvent is at least 5 dl/g, preferably from 5 to 40 clQ/g. When an ultra-high molecular weight polyolefin having an intrinsic viscosity [η] within the above range is used, not only a molecularly oriented shaped body having sufficient tensile strength can be obtained, but also the molecularly oriented molded body can be easily molded.

Organic phosphite stabilizer (B) The ultra-high molecular weight polyolefin composition, in addition to the above-mentioned ultra-high molecular weight polyolefin (A), contains a stabilizer that is eluted into a solvent used as a heating medium when stretching the ultra-high molecular weight polyolefin. Contains a resistant organic phosphite stabilizer (B).

As the organic phosphite stabilizer, conventionally known stabilizers can be used without particular restriction, but specifically, the following are used in terms of compatibility with ultra-high molecular weight polyolefins and elution resistance to the above solvents. Such compounds are preferably used.

Triphenyl phosphite, tris(nonylphenyl) phosphite, tris(2.
4-di-t-butylphenyl) phosphite, tetratridecyl-4,4゜-butylidenebis(3-methyl-et-butylphenyl)-diphosphite,
4,4゜-isobropylidene-diphenol alkyl phosphite (this alkyl is an alkyl having 12 to 15 carbon atoms), 4,4゛-isobropylidene bis(2-t-butylphenol) di(nonylphenyl) ) phosphite, tris(biphenyl)phosphite, tetra(tridecyl)-L,l,3-tris(2-methyl-5-t-butyl-4-hydroxyphenyl)butane diphosphite, tetra(tridecyl)-4 .4'-butylidene bis(
3-methyl-et-butylphenol) diphosphite, tris(3,5-di-t-butyl-4-hydroxyphenyl)phosphite, hydrogenated-4,4°-isobropylidenediphenol polyphosphite, bis(octyl) phenyl)◆Bis[4,4゜-butylidenebis(3-methyl-at-butylphenol)]・
l,6-hexaneol diphosphite, hexatridecyl-1,1,3-tris(2-methyl-4hydroxy-5-t-butylphenol) diphosphite, tris[4,4°-isobropylidene bis(2 -t-butylphenol)] phosphite, tris(l,3-distearoyloxyisobutyl)
Phosphite, 9. lO-dihydro9-oxer 10-phosphaphenanthrene-10-oxide, di(nonylphenyl)pentaerythritol diphosphite, phenyl◆4,4゜-isobropylidene diphenol●
Bentaerythritol diphosphite, bis(2.4-
di-t-butylphenyl) pentaerythritol diphosphite, bis(2,8-di-t-butyl-4-methylphenyl)
Pentaerythritol diphosphite, phenylbisphenol-A-pentaerythritol diphosphite, etc.

Further, the organic phosphite stabilizer used here also includes a phosphonite compound in which a carbon atom and a phosphorus atom are directly bonded. Specifically, tetrakis(2,4-di-t-butylphenyl)4.4°-biphenylene diphosphonite is mentioned.

Among these, particularly preferred organic phosphite stabilizers are the following compounds.

tris(2,4-di-t-butylphenyl) phosphite, tetratridecyl-4,4°-butylidenebis(3-methyl-et-butylphenol)-diphosphite,
4.4′-isobropylidene-diphenol alkyl phosphite (this alkyl is an alkyl having 12 to 15 carbon atoms), 4,4′-isobropylidene bis(2-t-butylphenol) di(nonylphenyl) ) phosphite, tetra(tridecyl)-1.1.3-tris(2-methyl-5
-t-butyl-4-hydroxyphenyl)butane diphosphite, tetra(tridecyl) -4.4゜-butylidene bis(
3-methyl-6-t-butylphenol) diphosphite, tris(3,5-di-t-butyl-4-hydroxyphenyl) phosphite, bis(octylphenyl) bis[4,4°-butylidene bis(3- Methyl-6-L-butylphenol)]
1,8-hexaneol diphosphite, hexatridecyl-1,1,3-tris(2-methyl-4hydroxy-5-t-butylphenol) diphosphite, tris[4,4°-isopropylidene bis(2 -t-butylphenol)] phosphite, di(nonylphenyl)pentaerythritol diphosphite, phenyl●4,4゜-isobropylidenediphenol
Pentaerythritol diphosphite, bis(2,4-
di-t-butylphenyl) pentaerythritol diphosphite, bis(2,6-di-t-butyl-4-methylphenyl)
Pentaerythritol diphosphite, phenylbisphenol-A-pentaerythritol diphosphite, tetrakis (2.4-di-t-butylphenyl) 4.4
'-biphenylene diphosphonite.

These organic phosphite stabilizers may be used alone or in combination.

The organic phosphite stabilizer (C) as described above has a total weight ffi of the ultra-high molecular weight polyolefin (A) and the diluent.
0.005 to 5 parts by weight, preferably 0.01 to 0.5 parts by weight, more preferably 0.05 parts by weight per 100 parts by weight.
It is used in an amount of ˜0.2 parts by weight. When this organic phosphite stabilizer (B) is used in an amount within the above range, the effect of improving heat resistance can be enhanced, and
It is economically advantageous and does not impair the properties of the resin, such as strength and elongation.

Hindered amine stabilizer (C) Ultra-high molecular weight polyolefin composition is used in addition to the above-mentioned ultra-high molecular weight polyolefin (A) and organic phosphite stabilizer (B) when drawing ultra-high molecular weight polyolefin. Contains a hindered amine stabilizer (C) that is difficult to be eluted by the solvent used as a heating medium.

As the hindered amine stabilizer, conventionally known compounds having a structure in which all the hydrogens bonded to carbons at the 2- and 6-positions of piperidine are replaced with methyl groups can be used, but there are specific examples. Specifically, the following compounds are preferably used in terms of compatibility with ultra-high molecular weight polyolefins and elution resistance to the above-mentioned solvents.

(1) Bis(2.2,6.6-tetramethyl-4-piveridyl) sebacate, (2) Dimethyl succinate-l-(2-hydroxyethyl)-4-hydroxy-2.2.6.6-tetra Methylpiperidine polycondensate, (3>poly[[6-(L,l,8.3-tetramethylbutyl)imino1.3.5-}riazine-2-4-diyl][(2,2,6 .6-tetramethyl-4-biperidyl)imino]hexamethylene ((2,2.6.6-
Te1-lamythyl-4-piperidyl)imino]] (4) Tetrakis(2.2,6.6-tetramethyl-4
-piveridyl)-1,2,3,4-butanetetracarpoxylate, (5) 2,2,B,6-tetramethyl-
4-biveridyl benzoate, (6) bis(1,2,6.6-pentamethyl-4-piperidyl)-2-(3.5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate , (7> bis-(N-methyl-2.2,8.6-tetramethyl-4-piperidyl) sebacate, (8) 1.1'-(1.2-ethanediyl) bis(3.
3.5.5-tetramethylpiperazinone), (9>(Mixto2.2,6.6-tetramethyl-4
-piperidyl/tridecyl)-1.2,3.4-butanetetracarpoxylate, (10) (Mixto 1,2,2,6.6-pentamethyl-4-biperidyl/tridecyl)-1.2.3 ．．
4-Butanetetracarboxylate, (.11) mixed (2.2,6.6-tetramethyl-4-piperidyl/β,β,β゛,β゜-tetramethyl-3.9-[2.4 ,8.10-tetraoxasbiro(
5.5) undecane] diethyl l-1.2,3.4-butanetetracarpoxylate, (L2) mixed f1,2,2.6.6-pentamethyl-4-biperidyl/β,β,β゛, β゜-tetramethyl-3.9-[2,4,8.10-tetraoxasp (5.5) undecanecodiethyl l-1.2,3.4-
Butanetetracarpoxylate, (13) N,N'-bis(3-aminobutyl)ethylenediamine-2-4-bis[N-butyl-N-(1,
2.2,6.6-pentamethyl-4-biperidyl)aminoco-6-chloro1.3.5-triazine condensate, (l4) poly[[+3-N-morpholyl]1.3.
5-triazine-2-4-diyl][(2,2,B,
6-tetramethyl-4-piperidyl)imino]hexamethylene [(2,2,6.6-tetramethyl-4-piperidyl)imino]], (15) N. N'-bis(2,2
．． Ili. Condensate of 6-tetramethyl-4-piperidyl)hexamethylenediamine and 1,2-dibromoethane, (1B) [N-(2.2.8.8-tetramethyl-4-
piperidyl)-2-methyl-2-(2.2,6.8-tetramethyl-4-piperidyl)imino]probionamide and the like.

Among these, particularly preferred hindered amine stabilizers are the above (2), (3), (4), (B), (
8), (9), (10), (11), (l2>, (l
3>, (l4), (l5> and ({6).

These hindered amine stabilizers may be used alone or in combination.

The above-mentioned hindered amine stabilizer (C) has a total weight of ultra-high molecular weight polyolefin (A) and diluent of 10
0.005 to 5 parts by weight, preferably 0 parts by weight
．． 01-06 5 parts by weight, more preferably 0.05-06
It is used in an amount of 0.2 parts by weight. When this hindered amine stabilizer (C) is used in an amount within the above range,
It can enhance the effect of improving heat resistance and weather resistance, is economically advantageous, and does not impair the properties of the resin, such as tensile elongation.

Metal salts of higher fatty acids (D) The ultra-high molecular weight polyolefin compound contains, in addition to the above-mentioned ultra-high molecular weight polyolefins (A), organic phosphite stabilizers (B) and hindered amine stabilizers (C), It may contain a metal salt (D) of a higher fatty acid that is difficult to be eluted by a solvent used as a heating medium when stretching an ultra-high molecular weight polyolefin.

Examples of metal salts of higher fatty acids include magnesium salts and calcium salts of higher fatty acids such as stearic acid, oleic acid, lauric acid, cabric acid, arachidonic acid, palmitic acid, behenic acid, l2-hydroxystearic acid, ricinoleic acid, and montanic acid. Salts, alkaline earth metal salts such as barium salts, alkali metal salts such as cadmium salts, zinc salts, lead salts, sodium salts, potassium salts, lithium salts, etc. are used. Specifically, the following compounds are preferably used in terms of compatibility with ultra-high molecular weight polyolefins and elution resistance to the above-mentioned solvents.

Magnesium stearate, magnesium laurate,
Magnesium palmitate, calcium stearate,
Calcium oleate, calcium laurate, barium stearate, barium oleate, barium laurate, barium arachidonate, barium behenate, zinc stearate, zinc oleate, zinc laurate, lithium stearate, sodium stearate, sodium palmitate , sodium laurate, potassium stearate, potassium laurate, calcium i2-hydroxystearate, calcium monocinate, etc.

These metal salts of higher fatty acids may be used alone or in combination.

The metal salt (D) of higher fatty acid as described above is 0.005 to 5 parts by weight, preferably 0.01 parts by weight, based on 100 parts by weight of the total weight of the ultra-high molecular weight polyolefin (A) and the diluent.
It is used in an amount of ~0.5 parts by weight, more preferably 0.05-0.5 parts by weight.

When this higher fatty acid metal salt (D) is used in an amount within the above range, the residual chlorine in the polymer derived from the female medium is sufficiently absorbed, so resin deterioration can be prevented. It is economically advantageous and does not impair the properties of the resin, such as tensile elongation.

Metal salts of higher fatty acids as described above have effects as lubricants, molding processability improvers, and rust preventive agents, so ultra-high molecular weight polyolefin compositions containing these metal salts have excellent moldability and are easy to mold. Effective for preventing rust on machines, etc.

The ultra-high molecular weight polyolefin composition contains the above-mentioned ingredients (A
), (B), (C) and (D), for example, heat stabilizers, weather stabilizers, pigments, dyes, lubricants, antistatic agents, etc., which are usually added to polyolefins.
It can be added within a range that does not impair the purpose of the present invention.

Next, a method for producing an ultra-high molecular weight polyolefin-based molecularly oriented molded article according to the present invention will be explained.

When producing a molecularly oriented body from the above-mentioned ultra-high molecular weight polyolefin composition, a diluent is added to the composition.

As the diluent, a solvent for ultra-high molecular weight polyolefin or various waxes having dispersibility for ultra-high molecular weight polyolefin are used.

The solvent used as a diluent preferably has a boiling point higher than the melting point of the ultra-high molecular weight polyolefin, more preferably higher than the melting point +20°C.

Specifically, such solvents include n-nonane, n-
-dodecane, n-undecane, n-tetradecane, n-
Octadecane or liquid paraffin, aliphatic hydrocarbon solvents such as kerosene, xylene, naphthalene, tetralin,
Aromatic hydrocarbon solvents such as butylbenzene, p-cymene, cyclohexylbenzene, diethylbenzene, benzylbenzene, dodecylbenzene, bicyclohexyl, decalin, methylnaphthalene, ethylnaphthalene or hydrogenated derivatives thereof, 1, 1, 2.2 -tetrachloroethane, pentachloroethane, hexachloroethane, 1,2
．． 3-}Lichloropropane, dichlorobenzene, 1,2
．． Examples include halogenated hydrocarbon solvents such as 4-1-lichlorobenzene and bromobenzene, mineral oils such as paraffinic process oil, naphthenic process oil, and aromatic process oil.

Further, as the wax used as a diluent, an aliphatic hydrocarbon compound or a derivative thereof is used.

The aliphatic hydrocarbon compound is a paraffin wax mainly composed of a saturated aliphatic hydrocarbon compound, and usually has a molecular weight of 2,000 or less, preferably 1.00032.
A paraffin wax having a molecular weight of 7 or lower, more preferably 800 or lower is used, and specifically, the following aliphatic hydrocarbon compounds are used.

N-alkanes with 22 or more carbon atoms such as docosane, tricosane, tetracosane, triacontane, or mixtures of these with lower n-alkanes, so-called paraffin wax separated and refined from petroleum, ethylene or ethylene and others Polyethylene such as medium/low pressure polyethylene wax, high pressure polyethylene wax, ethylene copolymer wax, medium/low pressure polyethylene, high pressure polyethylene, etc., which are low molecular weight polymers obtained by copolymerizing α-olefin with Waxes whose molecular weight has been lowered by methods such as waxes and oxides of these waxes, oxidized waxes modified with maleic acid, waxes modified with maleic acid, etc.

As the aliphatic hydrocarbon compound derivative, for example, one or more, preferably 1 to 2, particularly preferably 1 g of carboxyl, hydroxyl, Fatty acids and aliphatic compounds having a functional group such as a carbamoyl group, an ester group, a mercabuto group, a carbonyl group, and having a carbon number of 8 or more, preferably a carbon number of 12 to 50, or a molecular weight of 130 to 2,000, preferably 200 to 800. alcohol,
fatty acid amide, fatty acid ester, aliphatic mercabutan,
Aliphatic aldehydes, aliphatic ketones, etc. are used. Specifically, the following compounds are used.

Fatty acids such as cabric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, fatty alcohols such as lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, fatty acids such as cabrinamide, lauramide, valmitinamide, stearylamide, etc. Amides, fatty acid esters such as stearyl acetate, etc.

The diluent as described above is an ultra-high molecular weight polyolefin (A
) and in an amount such that it accounts for 97 to 20% by weight, preferably 85 to 40% by weight, based on the total weight of the diluent. When the diluent is used in an amount within the above range, melt-kneading and melt-forming are easy, the molded product has excellent stretchability, and it is possible to prevent surface roughness and stretch breakage of the molded product.

Melt kneading is generally carried out at 150-300°C, particularly at 170-200°C.
It is carried out at a temperature of 70°C. If the temperature is lower than the above range, the melt viscosity will be too high and melt molding will be difficult; if the temperature is higher than the above range, the molecular weight of the ultra-high molecular weight polyolefin will decrease due to thermal degradation, resulting in an excellent high It becomes difficult to obtain a molded article with high elasticity and high strength. The blending may be carried out by dry blending using a Henschel mixer V-type blender or the like, or may be carried out using a single-screw extruder or a multi-screw extruder.

Dove (
Melting or shaping of the spinning stock solution is generally carried out by melt extrusion or shaping. Specifically, filaments for drawing are obtained by melt extruding the dope through a spinneret.

At this time, the molten material immediately discharged from the spinneret may be subjected to drafting, that is, drawing in the molten state. Extrusion speed V of the molten resin within the die orifice. The ratio of the winding speed V of the cooled and solidified undrawn material can be defined as a draft ratio by the following formula.

Draft ratio -v/Vo (2) Such a draft ratio varies depending on the temperature of the mixture, the molecular weight of the ultra-high molecular weight polyolefin, etc., but it can usually be 3 or more, preferably 6 or more.

Next, the unstretched molded ultra-high molecular weight polyolefin thus obtained is subjected to a stretching treatment. The stretching is carried out so as to effectively impart at least uniaxial molecular orientation to the undrawn hollow body obtained from the ultra-high molecular weight polyolefin.

The unstretched molded article obtained from the ultra-high molecular weight polyolefin is generally stretched at 40 to 160'C, particularly at 80 to 145'C.
It is carried out at a temperature of As a heat medium for heating and maintaining the unrolled medium body at the above-mentioned temperature, any of air, steam, and limb medium can be used. However, as a heating medium, a liquid medium that is a solvent capable of eluting and removing the diluent described above and whose boiling point is higher than the melting point of the rod body composition, specifically, decalin, decane, kerosene, etc., is used. It is preferable to carry out the stretching operation in such a manner that the aforementioned diluent can be removed, the unevenness of stretching during the first stretching does not occur, and it is possible to achieve a high stretching ratio.

The means for removing the diluent from the ultra-high molecular weight polyolefin is not limited to the above-mentioned method, but the method for removing the diluent from the ultra-high molecular weight polyolefin is not limited to the method described above.
The diluent in the shaped object can also be removed by a method in which the object is stretched after treatment with a solvent such as hot ethanol, chloroform, or benzene, or a method in which the stretched object is treated with a solvent such as hexane, heptane, hot ethanol, chloroform, or benzene. By this method, a drawn product with high controllability and high strength can be obtained.

The stretching operation can be performed in one stage or in multiple stages of two or more stages. The stretching ratio depends on the desired molecular orientation and the associated effect of increasing the melting temperature, but is generally between 5 and 5.
80 times, preferably 10 to 50 times.

Generally, it is preferable to carry out the stretching operation by two or more stages of stretching, in which the stretching operation is carried out in the first stage while extracting the diluent in the ready-to-extrude molded product at a relatively low temperature of 80 to 120°C; From the second stage onward, it is preferable to carry out the stretching operation of the rod-shaped body at a temperature of 120 to 160°C, and at a temperature higher than the first stage stretching temperature.

In the case of a uniaxial stretching operation, tension stretching may be performed between rollers having different circumferential speeds.

In the case of a biaxially stretched film, it is sufficient to perform tensile stretching in the longitudinal direction between rollers having different circumferential speeds, and also to perform tensile stretching in the transverse direction using a tenter or the like. is also possible. Furthermore, in the case of a three-dimensional shaped object such as a container, a biaxially stretched or shaped object can be obtained by a combination of axial stretching and expansion stretching in the circumferential direction.

The molecularly oriented molded product thus obtained can be heat-treated under restrictive conditions if desired.

This heat treatment is generally carried out at 140-180°C, preferably at 15°C.
At a temperature of 0 to 175°C for 1 to 20 minutes, preferably 3 to 1
It can be done for 0 minutes. The heat treatment further advances the crystallization of the oriented crystal portions, shifts the crystal melting temperature to a higher temperature side, improves the strength and ambiguity, and further improves the creep resistance at high temperatures.

Effects of the Invention The ultra-high molecular weight polyolefin-based molecularly oriented molded article according to the present invention comprises an ultra-high molecular weight polyolefin (A) and specific amounts of the stabilizers (B) and (C) or a specific amount of the stabilizer (B). , (C) and (D), it has excellent long-term heat resistance stability and weather resistance, and maintains high tensile strength and high tensile modulus.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Ultra-high molecular weight polyethylene (intrinsic viscosity [η] -8.94c
lQ/g, measured in decalin solvent at 135°C) powder and 80 parts by weight of paraffin wax (manufactured by Nippon Seiro Co., Ltd., trade name: Luvax, melting point: 69°C) powder as a diluent, and an organic As a phosphite stabilizer, tris(2.4-di-t-butinolephenylene) phosphite (manufactured by Nippon Ciba Geigy Co., Ltd., trade name: PIIO) is used as a phosphite stabilizer.
0.1 parts by weight of SPIIIT [E 168), bis(2,2,6.8-tetramethyl-4-piperidyl) sebacate (manufactured by Sankyo Co., Ltd.) as a hindered amine stabilizer.
0.1 part by weight of (trade name: SANOL 770) was blended and melt-spun under the following conditions.

The mixture was passed through a screw extruder (screw diameter 25 mm,
L/D-25, manufactured by Thermoplastics),
After melt-kneading at a set temperature of 190° C., the melt was melt-spun using a spinning die with an orifice diameter of 2111 attached to an extruder. Next, the extruded melt was taken under the conditions of an air gap of 180 cm and a draft ratio of 35 times, and was cooled and solidified in air to obtain an undrawn fiber.

Furthermore, the undrawn fibers were drawn under the following conditions to obtain molecularly oriented fibers.

Two-stage stretching was performed using three godet rolls. At this time, the heating medium for the first drawing}Ω was n-decane at a temperature of 110°C, and the heating medium for the second drawing tank was triethylene glycol at a temperature of 145°C. The effective length of each tank was 50 cm'. During stretching, the rotation speed of the first godet roll was set at 0.57 min, and the rotation speed of the third godet roll was set at 12.5/min (stretching ratio: 25/min).
times).

The rotational speed of the second godet roll was appropriately selected within a range that allowed stable operation. Almost all of the initially mixed paraffin wax was extracted into n-decane during stretching. Next, the obtained molecularly oriented fibers were washed with water and dried under reduced pressure at room temperature overnight.

The long-term heat resistance of the obtained molecularly oriented fibers is determined by the absorption rate of
Evaluation was made based on changes in intrinsic viscosity [η] and changes in tensile properties due to heat aging.

Furthermore, the weather resistance of the obtained molecularly oriented fibers was evaluated by changes in tensile properties due to light irradiation.

Measurement of oxygen absorption rate> A sheet of molecularly oriented fibers was placed in an oxygen atmosphere at 130°C using a CBP-4 UV type polymer material deterioration measuring device manufactured by Shibayama Scientific Instruments Co., Ltd., and the molecularly oriented fibers per gram of fibers were measured after 20 hours. The amount of oxygen absorption converted to the drifting state was determined as illlJ. The smaller the amount of oxygen absorbed, the better the stability against oxidation.

<Heating Test> The molecularly oriented fibers were left in a gear oven (Perfect Oven manufactured by Tabai Seisakusho) in an air atmosphere set at 100° C. for 500 hours, and then subjected to physical property measurements. The smaller the decrease in the intrinsic viscosity [η] due to aging, the better the heat resistance stability.

Measurement of tensile properties> Tensile strength was measured as tensile properties using DCS-5 manufactured by Shimadzu Corporation.
APj was determined at room temperature (23°C) using a 0M type tensile tester. The test length between the clamps at this time is 100 m
m and the tensile rate was 1.0 On+m/min (100% strain rate). The +i modulus was calculated using the slope of the tangent at the initial elastic modulus. The fiber cross-sectional area required for calculation is calculated by setting the density to 0.
It was calculated from the weight as 960g/cc.

The smaller the decrease in tensile strength, the better the heat resistance stability.

Weather Resistance Test> A dust resistance acceleration test of molecularly oriented fibers was conducted in accordance with STM D 1499. The promoting conditions were a black panel temperature of 63±3°C and a light ffi (300 to 40°C) twice that of the standard condition.
7 in the Or++g region. 5 IIIW/+In-c
d). The tensile strength of the molecularly oriented fibers was measured after 600 hours of pre-irradiation. The smaller the decrease in tensile strength, the better the weather resistance.

The results are shown in Table 1.

Example 2 Molecularly oriented fibers were prepared in the same manner as in Example 1, except that 0.3 parts by weight of calcium stearate (manufactured by Sankyoki ■) was added as a higher fatty acid metal salt to the composition of Example 1. The above measurements were carried out.

The fruits are shown in Table 1.

Example 3 In Example], as a hindered amine stabilizer,
Dimethyl-1-(2-hydroxyethyl)-4 succinate
-Hydroxy-2.2,8.6-tetramethylbiveridine polycondensate (manufactured by Nippon Ciba Geigy Co., Ltd., trade name: KIMASORB 622LD) was used in the same manner as in Example], except that 0 or 1 part by weight was used. Molecularly oriented fibers were obtained and the δp1 constant was determined.

The results are shown in Table 1.

Example 4 In Example 1, as a hindered amine stabilizer,
Dimethyl succinate-i-(2-hydroxyethyl)-4
-Hydroxy-2.2.6.6-tetramethylpiveridine polycondensate (manufactured by Ciba Geigy Japan Co., Ltd., trade name: Chimasorb 622LD) was used in an amount of 1 part by weight, and calcium stearate was added as a higher fatty acid metal salt. (
Molecularly oriented fibers were obtained in the same manner as in Example 1, except that 0.3 parts by weight of Sankyoki (manufactured by Sankyoki ■) were added, and the above measurements were performed.

The results are shown in Table 1.

Example 5 In Example 1, as the organic phosphite stabilizer,
Bis(2,6-di-t-butyl-4-methylphenyl)
Poly[[8-(1.1,3.3-te) 1.3.5-triazine-2.4-diyl]
[(2,2,6.6-tetramethyl-4-biveridyl)
Example 1 except that 0.1 part by weight of hexamethylene [(2.2,6.6-tetramethyl-4-piveridyl)imino] (manufactured by Nippon Ciba Geigy Co., Ltd., trade name: Chimasorb 944LD) was used. Molecularly oriented fibers were obtained in the same manner as above and subjected to the P1 determination.

The results are shown in Table 1.

Example 6 In Example 1, as the organic phosphite stabilizer,
Bis(2,6-di-t-butyl-4-methylphenyl)
Pentaerythritol diphosphite (manufactured by Adeka Argus Chemical ■, trade name: MARK PEP-36) was added to 0.
1 part by weight, as a hindered amine stabilizer, poly[
[6-(1,1,3.3-tetramethylbutyl)imino-1,3.5-}riazine-2,4-diyl][(2
,2,6,B-tetramethyl-4-piperidyl)imino]hexamethylene[(2,2,6.6-tetramethyl-
4-piperidyl) iminoco] (manufactured by Ciba Geigy Japan),
The same procedure as in Example 1 was carried out, except that 0.1 part by weight of (trade name: KimaSorb 944LD) was used and 0.3 part by weight of calcium stearate (manufactured by Sankyoki ■) was added as a higher fatty acid metal salt. Obtain molecularly oriented fibers, and the δN
I made a decision.

The fruits are shown in Table 1.

Example 7 In Example 1, as an organic phosphite stabilizer,
Bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite (manufactured by Adeka Argus Chemical, trade name: MARK PEP-36)
0.1 part by weight, as a hindered amine stabilizer, tetrakis(2,2,6.6-tetramethyl-4-piperidyl)-1.2.3.4-butante-1-lacarboxylate (Adeka Argus Chemical ■ Manufacturer, product name: MARK
Molecularly oriented fibers were obtained in the same manner as in Example 1, except that 0.1 ffl part of LA-57) was used, and the above Jll+ determination was performed.

The results are shown in Table 1.

Example 8 In Example 1, as the organic phosphite stabilizer,
Bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite (manufactured by Adeka Argus Chemical, trade name: MARK l) EP-36
) as a hindered amine stabilizer,
Tetrakis (2,2,8,6-tetramethyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate (manufactured by Adeka Argus Chemical ■, product name: MARK
Molecular orientation was carried out in the same manner as in Example 1, except that 0.1 part by weight of LA-57) was used and 0.3 part by weight of calcium stearate (manufactured by Sankyoki ■) was added as a higher fatty acid metal salt. Fibers were obtained and the measurements described above were performed.

The results are shown in Table 1.

Example 9 In Example 1, as the organic phosphite stabilizer,
Tetrakis(2,4-di-t-butylphenyl)4,4
゛-Biphenylene diphenyl phosphonite (manufactured by Sandoz, product name: SANDOSTAB P-EPQ)
．． Molecularly oriented fibers were obtained in the same manner as in Example 1, except that 0.3 parts by weight of calcium stearate (manufactured by Sankyoki ■) was used as a higher fatty acid metal salt, and the above measurements were carried out. I did it.

The results are shown in Table 1.

Example 10 In Example 1, as an organic phosphite stabilizer,
Tetrakis(2,4-di-t-butylphenyl)-4.
4'-Biphenylene diphenyl phosphonite (manufactured by Sandoz, product name: SANDOSTAI3 P-EPQ)
Molecularly oriented fibers were obtained in the same manner as in Example 1, except that 0.1 part by weight of was used, and 0.3 parts by weight of calcium stearate (manufactured by Sankyoki ■) was added as a higher fatty acid metal salt. The above i1111 determination was performed.

The results are shown in Table 1.

Comparative Example 1 Molecularly oriented fibers were obtained in the same manner as in Example 1, except that neither the organic phosphite stabilizer nor the hindered amine stabilizer was used, and the above measurements were performed.

The results are shown in Table 1.

Claims (1)

[Claims] 1) (A) ultra-high molecular weight polyolefin; (B) organic phosphite stabilizer: (A) 0.005 to 5 parts by weight per 100 parts by weight of ultra-high molecular weight polyolefin; C) Hindered amine stabilizer: (A) An ultra-high molecular weight polyolefin-based molecularly oriented molded article containing 0.005 to 5 parts by weight based on 100 parts by weight of the ultra-high molecular weight polyolefin. 2) (A) ultra-high molecular weight polyolefin; (B) organic phosphite stabilizer: (A) 0.005 to 5 parts by weight per 100 parts by weight of ultra-high molecular weight polyolefin; (C) hindered amine stabilizer : (A) 0.005 to 5 parts by weight per 100 parts by weight of ultra-high molecular weight polyolefin; (D) Metal salt of higher fatty acid: (A) 0.005 to 5 parts by weight per 100 parts by weight of ultra-high molecular weight polyolefin. An ultra-high molecular weight polyolefin-based molecularly oriented molded article comprising parts by weight.