JPH04255351A - High strength film material composed of laminate and use thereof - Google Patents

Abstract

PURPOSE:To provide a high strength film material having lightweight properties, excellent in gas barrier properties, mechanical strength such as tensile strength and low temp. characteristics and holding proper flexibility. CONSTITUTION:A high strength film material is composed of a laminate prepared by laminating polyolefinic resin layers to both surfaces of a core layer consisting of a molecularly oriented molded body of an ultrahigh MW ethylenic polymer whose intrinsic viscosity [eta] is at least 5dl/g and a union fabric or mixed fabric of one or more kind of a fiber composed of aramide, polyamide or polyester. By using the aforementioned specific materials, the high strength film material having lightweight properties and excellent in gas barrier properties, strength and low temp. characteristics is provided and suitably used as the material of a balloon such as a meteorological observation balloon, an aerial photographing balloon or an advertising balloon.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a high-strength membrane material made of a laminate and its uses, and more particularly to a heat-resistant membrane material made of a laminate that is lightweight and has excellent gas barrier properties, strength, and low-temperature properties. The present invention relates to a high-strength membrane material that can be easily joined by fusion bonding, and to balloons such as weather observation balloons, aerial photography balloons, and advertising balloons, which are suitable uses for the high-strength membrane materials.

0002

[Prior art and its problems] Conventionally, membrane materials for balloons such as weather observation balloons, aerial photography balloons, and advertising balloons have been made of knitted fabrics such as polyester fibers and polyamide fibers as core materials. A laminate coated with polyester resin or vinyl chloride resin on both sides,
A laminate is used in which films made of polyester resin or vinyl chloride resin are laminated on both sides of the knitted fabric. By the way, balloons used for such purposes are extremely heavy overall, and their maneuverability becomes a problem, so they must be lightweight, have excellent gas barrier properties, and have high tensile strength. is required.

However, the laminates that have been used as membrane materials for balloons do not necessarily have sufficient mechanical strength such as tensile strength, and in order to have sufficient strength to withstand use, it is necessary to It had to be formed thickly and the overall weight was heavy, making it difficult to say that it was suitable as a membrane material for balloons. Under these circumstances, while proceeding with the development of materials suitable for membrane materials for balloons, the applicant has developed a core consisting of cross or parallel threads made of ultra-high molecular weight ethylene polymer fibers. A laminate consisting of a core layer and an outer layer made of an olefin polymer provided on one or both sides of the core layer is lightweight and has excellent gas barrier properties, as well as mechanical strength such as tensile strength and low temperature resistance. Having found out that it has excellent properties, I filed a patent application (Japanese Patent Application No. 1-184213). Furthermore, in the process of retesting the invention, the applicant found that by selecting and using a specific material for the core layer, a membrane material with superior high strength could be obtained, and that a specific material for the outer layer could be obtained. The present invention was achieved based on the knowledge that a membrane material with the above-mentioned effects can be obtained by using the above-mentioned method.

0004

OBJECT OF THE INVENTION Therefore, the object of the present invention is to provide a high-strength laminate that is lightweight, has excellent gas barrier properties, and has excellent mechanical strength such as tensile strength and low-temperature properties, and can be easily joined by heat fusion. An object of the present invention is to provide a membrane material and a balloon such as a weather observation balloon, an aerial photography balloon, and an advertising balloon using the membrane material.

[0005]

[Means for Solving the Problems] The present invention has been proposed to achieve the above-mentioned object, and includes a blended or blended fabric of a molecularly oriented molded product of a specific polymer and a specific fiber. It is characterized by being used as a core layer. That is, according to the present invention, a molecularly oriented molded article of an ultra-high molecular weight ethylene polymer having an intrinsic viscosity [η] of at least 5 dl/g, and one or two selected from the group consisting of aramid, polyamide, and polyester. A high-strength membrane material comprising a laminate having a core layer made of a woven or blended fabric with at least one type of fiber and a polyolefin resin layer laminated on at least one surface thereof, and a balloon using the membrane material are provided. In this specification, the intrinsic viscosity [η] refers to the value measured in decalin at 135°C.

Furthermore, according to the present invention, the polyolefin resin is linear low density polyethylene (L-LDP).
E), especially a density of 0.90 to 0.94 g/cm3
, melt index 1 to 50g/10min,
Ethylene and α having 4 to 10 carbon atoms with a melting point of 110 to 130°C and an ethylene content of 90 to 98 mol%
- when it is a random copolymer with olefin, and the ultra-high molecular weight ethylene polymer is a random copolymer with ethylene;
α-olefin having 3 or more carbon atoms, especially butene-1
, 4-methylpentene-1, hexene-1, and decene-1. Contains an average of 0.1 to 20 pieces,
When it is a copolymer of ethylene and α-olefin, a high-strength membrane material with even better properties as described above can be obtained.Balloons using this membrane material are lightweight, have excellent gas barrier properties, and have excellent mechanical properties such as tensile strength. It also has excellent strength and low-temperature properties.

[0007]

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an ultra-high molecular weight ethylene polymer having an intrinsic viscosity [η] of at least 5 dl/g, particularly an α-olefin having 3 or more carbon atoms.
A molecularly oriented molded article of a copolymer of ethylene and α-olefin containing an average of 0.1 to 20 pieces per 000 pieces, and one or more types of fibers selected from the group consisting of aramid, polyamide, and polyester. A high-strength membrane material consisting of a laminate having a core layer made of a mixed or blended fabric and a polyolefin resin layer laminated on at least one side has outstanding physical properties, and this membrane material is particularly suitable for use in balloons. It was completed based on the knowledge that it is possible to

The high-strength membrane material according to the present invention is an ultra-high molecular weight ethylene copolymer having an intrinsic viscosity [η] of at least 5 dl/g, preferably 7 to 30 dl/g, as measured in a decalin solvent at 135°C. A core layer is a core layer of a molecularly oriented molded product and one or more fibers selected from the group consisting of aramid, polyamide, and polyester, and a polyolefin resin layer is laminated on at least one side of the core layer. It consists of the body.

Examples of ultra-high molecular weight ethylene polymers include not only ultra-high molecular weight polyethylene but also ethylene and α-olefins having 3 or more carbon atoms, such as propylene, butene-1, pentene, etc. -1, 4
-methylpentene-1, hexene-1, heptene-1,
A copolymer with one or more selected from the group consisting of octene-1 and decene-1 is preferably used,
Among them, copolymers of ethylene and one or more selected from the group consisting of butene-1, 4-methylpentene-1, hexene-1, octene-1, and decene-1 have high tensile strength. It has excellent mechanical strength. Furthermore, when the ultra-high molecular weight ethylene polymer is a copolymer of ethylene and α-olefin, α
- It is desirable that the olefin comonomer is contained in an average of 0.1 to 20, preferably an average of 0.5 to 10, per 1000 carbon atoms.

Ultra-high molecular weight ethylene α-
The α-olefin component in the olefin copolymer was determined using an infrared spectrophotometer (manufactured by JASCO Corporation). In other words, we measured the absorbance at 1378 cm-1, which represents the bending vibration of the methyl group of the α-olefin incorporated into the ethylene chain, and from this we measured the absorbance in advance using a 13C nuclear magnetic resonance apparatus.
It was calculated from the value measured by converting it into the number of methyl branches per 1000 carbon atoms using an inspection line created using a model compound.

[0011] When the content of the α-olefin comonomer in the copolymer is within the above range, the α-olefin component forms an intermolecular entanglement structure that is effective in achieving high breaking energy, and this structure A blended or blended fabric of the molecularly oriented molded product and one or more types of fibers selected from the group consisting of aramid, polyamide, and polyester has appropriate flexibility and contributes to improving physical properties such as strength. At the same time, it is lightweight and has excellent mechanical strength.

As mentioned above, the core layer of the high-strength membrane material of the present invention is made of a molecularly oriented molded product of an ultra-high molecular weight ethylene polymer and one or more types selected from the group consisting of aramid, polyamide, and polyester. The fibers are interwoven or blended with the above-mentioned fibers, and the respective fibers are interwoven in either the vertical direction or the horizontal direction, or mixed with the molecularly oriented molded article. In either case, the molecularly oriented molded product covers 50% of the entire core layer.
% or more is preferable. The main material forming the core layer is a molecularly oriented molded product, stretched monofilament, or multifilament of an ultra-high molecular weight ethylene polymer, and a stretched film or stretched tape of the polymer is used as the multifilament by a carding machine. You may also use defibrated threads that have been defibrated. The intrinsic viscosity [η] of the ultra-high molecular weight ethylene polymer is 5d.
If it is less than l/g, even if the stretching ratio is increased,
Molecularly oriented molded products with sufficient strength cannot be obtained, and on the other hand, those with [η] of 30 dl/g or more have extremely high melt viscosity at high concentrations, causing melt fractures during extrusion and poor melt spinnability. Therefore, it is not possible to obtain a suitable filament.

The structure of the knitted fabric used as the core layer can be obtained by interweaving or interweaving the above-mentioned fibers by any weaving method such as plain weave, twill weave, or twine weave. You can also mix and match. In order to achieve even better adhesion to the polyolefin resin forming the outer layer, the knitted fabric is preferably one with a coarse mesh pattern, but it is preferable to use a knitted fabric with a coarse number of threads, as the compatibility between the two is excellent. Suitable adhesion can also be achieved with In the case of a dense number of weaving, the fibers forming the core layer are prepared in advance or after weaving, for example, in JP-A-57-177032, JP-A-60-146078, JP-A-63-213530.
The adhesive force between the outer layer and the core layer can be increased by applying corona discharge treatment or plasma discharge treatment according to the method described in the above publication. Although the denier of each fiber forming the core layer is not particularly limited, it is usually 50 to 3000 deniers, particularly preferably 100 to 1000 deniers. The thickness of the core layer is usually 0.03 to 2 mm, preferably 0.03 to 2 mm.
．． 05 to 0.5 mm.

The high-strength membrane material of the present invention consists of a laminate in which polyolefin resin layers are laminated on both sides of a core layer.
The laminate can be produced by a hot roll lamination method in which a film or sheet made of polyolefin resin is pressed onto both sides of the core layer using a hot roll, by an extrusion coating method using an extrusion laminating device, or by pressing both together using an adhesive. It can be easily obtained by a method such as

In the hot roll lamination method, the roll temperature is usually 140°C, preferably 130°C or less, so that the core layer does not deteriorate in physical properties due to heating.
Pressure bonding with a roll is performed for 30 seconds or less, preferably 5 seconds or less.

In the extrusion coating method, after coating both sides of the core layer with polyolefin resin, it is necessary to quickly cool the coated resin in order to minimize the heat history to the core layer.
Usually the coating speed is 20 m/min or more, preferably 3 m/min.
0 m/min or more, the coating film thickness is 0.2 mm or less, preferably 0.1 mm or less, and the extrusion resin temperature is 30
It is preferable to set the temperature to 0°C or lower.

In the method using an adhesive, a resin or rubber adhesive that exhibits excellent adhesion to both the core layer and the polyolefin resin layer, such as vinyl thermoplastic resin, acrylic resin, chloroprene resin, EBR, etc.
Rubber adhesives such as NBR and SBR can be used, but vinyl thermoplastic resin adhesives are most preferably used. In this method, the adhesive used is dissolved in a good solvent to form a solution type, which is applied to a film or sheet made of polyolefin resin using a reverse roll coater, etc., and then set on the core layer and passed through nip rolls. Then, the two are pasted together. By the method described above, a lightweight, high-strength laminate with excellent gas barrier properties can be obtained.

Examples of the polyolefin resin include low density polyethylene, medium density polyethylene or high density polyethylene, linear low density polyethylene, polypropylene, crystalline propylene-ethylene copolymer, propylene-butene-1 copolymer, ethylene- Crystalline olefin homopolymers or copolymers such as butene-1 copolymer, ethylene-propylene-butene-1 copolymer, ethylene-propylene copolymer rubber, ethylene-propylene-nonconjugated diene copolymer Rubber, olefin elastomers such as copolymers of α-olefins such as ethylene and conjugated dienes such as butadiene or non-conjugated dienes such as ethylidene norbornene or dicyclopentadiene;
Films of olefin polymers such as ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-vinyl alcohol copolymer, ethylene-vinyl chloride copolymer, etc., or these polymers are combined with unsaturated carboxylic acids, etc. films of graft-modified olefin polymers; films of olefin rubber-like polymers such as ethylene-propylene rubber and ethylene-propylene-diene rubber; polar group-containing olefin-based polymers such as ethylene-vinyl acetate copolymers and ionomer resins; Examples include polymers, but linear low-density polyethylene (L-LDPE), ethylene-
Vinyl acetate copolymers and ionomer resins are preferably used, and among them, they have a density of 0.90 to 0.94 g/cm3, a melt index of 1 to 50 g/10 min, and a melting point of 11, since they have excellent properties as described above.
0 to 130°C and ethylene content 90 to 98
A random copolymer of ethylene and an α-olefin having 4 to 10 carbon atoms (L-LDPE) in mol% is most preferably used. These polyolefin resins are
The same material or different materials may be used for both outer layers. In addition, by adding coloring agents such as pigments to polyolefin resins, it is possible to form a surface layer with a rich sense of color. Agents can be added as desired.

The ultra-high molecular weight ethylene polymer, which is the raw material for the molecularly oriented molded product used as the main material forming the core layer, is composed of ethylene or ethylene and the above-mentioned comonomers according to the periodic table IVb, Vb, VIb, Slurry polymerization is carried out in, for example, an organic solvent in the presence of a catalyst consisting of a transition metal compound of Group VIII and a metal hydride or organometal of Groups I to III of the Periodic Table, and its intrinsic viscosity [η
] to 5 dl/g or more.

[0020] As a method for producing a molecularly oriented molded article,
For example, JP-A No. 56-15408 and JP-A No. 5
As described in Japanese Patent Application No. 9-187614, a diluent is added to the ultra-high molecular weight ethylene polymer to improve extrusion moldability, and then stretched to form a stretched product such as fiber or tape. Here is an example of how to do this.

As the diluent, a solvent for the ultra-high molecular weight ethylene polymer and various wax-like substances having dispersibility for the ultra-high molecular weight ethylene polymer are used.

The solvent preferably has a boiling point higher than the melting point of the copolymer, more preferably higher than the melting point +20°C. Specifically, such solvents include n-nonane, n-decane, n-undecane, n-dodecane, n-
Tetradecane, n-octadecane or liquid paraffin, aliphatic hydrocarbon solvents such as kerosene, xylene, naphthalene, tetralin, butylbenzene, p-cymene, cyclohexylbenzene, diethylbenzene, pentylbenzene, dodecylbenzene, bicyclohexyl, decalin, methylnaphthalene , aromatic hydrocarbon solvents such as ethylnaphthalene or hydrogenated derivatives thereof, 1,1,2,2
-tetrachloroethane, pentachloroethane, hexachloroethane, 1,2,3-trichloropropane, dichlorobenzene, 1,2,4-trichlorobenzene,
Examples include halogenated hydrocarbon solvents such as bromobenzene, mineral oils such as paraffinic process oils, naphthenic process oils, and aromatic process oils.

[0023] As the waxes, aliphatic hydrocarbon compounds or derivatives thereof are used.

The aliphatic hydrocarbon compounds are mainly saturated aliphatic hydrocarbon compounds, and usually have a molecular weight of 2.
000 or less, preferably 1000 or less, more preferably 800 or less, which is called a paraffin wax. These aliphatic hydrocarbon compounds include n-alkanes having 22 or more carbon atoms such as docosane, tricosane, tetracosane, and triacontane, mixtures of these with lower n-alkanes as main components, and separation and refinement from petroleum. So-called paraffin wax, medium-low pressure polyethylene wax, which is a low molecular weight polymer obtained by copolymerizing ethylene or ethylene with other α-olefins;
High-pressure polyethylene wax, ethylene copolymer wax, medium/low-pressure polyethylene, high-pressure polyethylene, and other polyethylene waxes whose molecular weight has been lowered by heat degradation, oxides of these waxes, oxidized waxes such as maleic acid modified waxes, and maleic waxes. Examples include acid-modified wax.

Examples of aliphatic hydrocarbon compound derivatives include one or more carboxyl groups, preferably one or two carboxyl groups, particularly preferably one carboxyl group, at the terminal or inside of an aliphatic hydrocarbon group (alkyl group, alkenyl group). fatty acids having 8 or more carbon atoms, preferably 12 to 50 carbon atoms, or a molecular weight of 130 to 2000, preferably 200 to 800, which are compounds having a functional group such as a hydroxyl group, a carbamoyl group, an ester group, a mercapto group, or a carbonyl group; fatty alcohol, fatty acid amide, fatty acid ester,
Examples include aliphatic mercaptans, aliphatic aldehydes, aliphatic ketones, and the like. Specifically, the fatty acids include capric acid, lauric acid, myristic acid, palmitic acid,
Examples of stearic acid, oleic acid, aliphatic alcohol such as lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, aliphatic amide such as caprinamide, lauramide, palmitinamide, stearylamide, and fatty acid ester include stearyl acetate. can.

[0026] The ratio of the ultra-high molecular weight ethylene polymer to the diluent varies depending on the type thereof, but is generally 3:97 to 80:20, particularly 15:85 to 60:40 by weight. It is better to use it as a ratio. If the amount of the diluent is lower than the above range, the melt viscosity will become too high, making melt kneading and melt extrusion difficult, and the surface of the molecularly oriented molded product will be markedly rough, easily causing stretching breakage and the like. On the other hand, if the amount of the diluent is larger than the above range, melt-kneading will become difficult and the molded product will have poor stretchability.

[0027] Melt kneading is generally carried out at 150 to 300°C.
In particular, it is desirable to carry out the process at a temperature of 170 to 270°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 melt viscosity will be The molecular weight of high molecular weight polyethylene decreases, making it difficult to obtain a molded article with high elastic modulus and high strength. The blending may be performed by dry blending using a Henschel mixer, a V-type blender, or the like, or by melt mixing using a single-screw or multi-screw extruder.

[0028] Extrusion molding is generally carried out by melt extrusion molding. For example, by melt extrusion through a spinneret, a filament for drawing is obtained; by extrusion through a flat or ring die, a film, sheet, or tape for drawing is obtained; and by further extrusion through a circular die, A pipe (parison) for stretch blow molding is obtained.

[0029] The stretching operation can be carried out in one stage or in multiple stages of two or more stages. The stretching ratio depends on the desired molecular orientation and the accompanying effect of increasing the melting temperature.
Satisfactory results can be obtained if the stretching operation is carried out at a stretching ratio of generally 5 to 80 times, particularly 10 to 50 times. The stretched molded product such as fiber or tape of ultra-high molecular weight ethylene polymer obtained in this way has a weight of 1.5G.
Maintains tensile strength of Pa or higher and tensile modulus of 20 GPa or higher.

[0030]

According to the present invention, the material constituting the core layer has moderate flexibility and excellent tensile strength, and the polyolefin resin layers formed on both sides of the core layer have excellent tensile strength. Combined with gas barrier properties and low temperature properties,
A high-strength membrane material consisting of a laminate that has the above-mentioned physical properties and can be easily joined by heat fusion is provided, and this membrane material is used as a membrane material for balloons such as weather observation balloons, aerial photography balloons, and advertising balloons. It is suitably used as

[0031]

[Examples] The present invention will be explained below with reference to Examples. <Polymerization of ultra-high molecular weight ethylene/butene-1 copolymer> An ultra-high molecular weight ethylene/butene-1 copolymer was slurry polymerized using a Ziegler catalyst and 1 liter of n-decane as a polymerization solvent. A mixed monomer gas containing ethylene and butene-1 in a molar ratio of 97.2:2.8 was continuously supplied to the reactor so as to maintain a constant pressure of 5 kg/cm2. Polymerization was completed in 2 hours at a reaction temperature of 70°C. The yield of the obtained ultra-high molecular weight ethylene/butene-1 copolymer powder was 160 g, the intrinsic viscosity [η] (decalin: 135°C) was 8.2 dl/g, and the butene-1 content determined by an infrared spectrophotometer was 1.5 per 1000 carbon atoms
It was.

<Preparation of stretched and oriented ultrahigh molecular weight ethylene/butene-1 copolymer> 20 parts by weight of the ultrahigh molecular weight ethylene/butene-1 copolymer powder obtained by the above polymerization and paraffin wax (melting point = 69 °C, molecular weight = 490)8
The mixture with 0 parts by weight was melt-spun under the following conditions. To 100 parts by weight of the mixture, 0.0% of 3,5-di-tert-butyl-4-hydroxytoluene was added as a process stabilizer.
1 part by weight was added. Next, the mixture was heated to a set temperature of 190°C using a screw extruder (screw diameter = 25 mm, L/D = 25, manufactured by Thermoplastics).
Melt-kneading was performed. Subsequently, the mixed melt was melt-spun using a spinning die with an orifice diameter of 2 mm attached to the extruder. The extrusion melt was taken off at a draft ratio of 36 times through an air gap of 180 cm, cooled and solidified in air, and undrawn fibers were obtained. Furthermore, the undrawn fibers were drawn under the following conditions.

Two-stage stretching was carried out using three godet rolls. At this time, the heating medium in the first drawing tank was n-decane at a temperature of 110°C, and the heating medium in the second drawing tank was triethylene glycol at a temperature of 145°C. The effective length of each tank was 50 cm. When stretching,
By setting the rotation speed of the first godet roll to 0.5 m/min and changing the rotation speed of the third godet roll, oriented fibers with a desired drawing ratio were obtained. The rotational speed of the second godet roll was appropriately selected within a range that allowed stable stretching. Almost all of the initially mixed paraffin wax is n-
Extracted into decane. Thereafter, the oriented fibers were washed with water, dried under reduced pressure at room temperature overnight, and then subjected to measurement of various physical properties. Note that the stretching ratio was calculated from the rotational speed ratio of the first godet roll and the third godet roll.

<Measurement of tensile properties> The elastic modulus and tensile strength were measured at room temperature (23° C.) using a tensile tester model DCS-50M manufactured by Shimadzu Corporation. At this time, the sample length between the clamps was 100 mm, and the tensile speed was 100 mm.
/min (100%/min strain rate). The elastic modulus was calculated using the slope of the tangent at the initial elastic modulus. The fiber cross-sectional area required for calculation was calculated from the weight, assuming a density of 0.960 g/cc.

<Tensile modulus and strength retention after heat history> The heat history test was conducted using a gear oven (Perfect Oven:
This was done by leaving it in a container (manufactured by Tabai Seisakusho). The sample had a length of about 3 m, and was folded over a stainless steel frame equipped with a plurality of pulleys at both ends to fix both ends of the sample. At this time, both ends of the sample were fixed to the extent that the sample did not sag, and no tension was actively applied to the sample. The tensile properties after the thermal history were measured based on the description of the measurement of the tensile properties described above.

<Measurement of Creep Resistance> Creep resistance was measured using a thermal stress strain measuring device TMA/SS10 (manufactured by Seiko Electronics Co., Ltd.) with a sample length of 1 cm and an ambient temperature of 70°C.
℃, and the loading was carried out under accelerated conditions with a weight corresponding to 30% of the breaking load at room temperature. In order to quantitatively evaluate the amount of creep, the following two values were determined. That is, the values are the value of creep elongation (%) CR90 when 90 seconds have elapsed after applying a load to the sample, and the value of average creep rate (sec-1) ε when 180 seconds have elapsed from the time when 90 seconds have elapsed.

Table 1 shows the tensile properties of the multifilament obtained by bundling a plurality of drawn and oriented fibers.

The original crystal melting peak of the ultra-high molecular weight ethylene-butene-1 copolymer drawn filament (Sample-1) was 126.7°C, and Tp relative to the total crystal melting peak area.
The percentage was 33.8%. Also, the creep resistance is C
R90=3.1%, ε=3.03×10-5sec-
It was 1. Furthermore, after heat history at 170°C for 5 minutes, the elastic modulus retention rate was 102.2%, and the strength retention rate was 102.
No deterioration in performance due to thermal history was observed at 5%. Also, the amount of work required to break the drawn filament is 10.3
kg・m/g, and the density is 0.973g/cm3
, the dielectric constant is 2.2, and the dielectric loss tangent is 0.02.
4%, and the impulse voltage breakdown value is 180kV/
It was mm. The reduction rate of multifilament knot strength and loop strength with respect to linear strength was 38%, respectively.
It was 36%.

<Polymerization of ultra-high molecular weight ethylene/octene-1 copolymer> Using a Ziegler catalyst, n-decane-1
Slurry polymerization of ethylene was carried out using 1 liter of polymerization solvent. At this time, 12 octene-1 was used as a comonomer.
5 ml and 40 Nml of hydrogen for molecular weight adjustment were added all at once before starting the polymerization to start the polymerization. Ethylene gas was continuously supplied to the reactor so as to maintain a constant pressure of 5 kg/cm 2 , and the polymerization was completed at 70° C. for 2 hours. The yield of the obtained ultra-high molecular weight ethylene/octene-1 copolymer powder was 178 g, and its intrinsic viscosity [η] (decalin, 135
°C) is 10.66 dl/g, and the octene-1 comonomer content by infrared spectrophotometer is 0.0.
There were 5 pieces.

<Preparation of drawn and oriented ultra-high molecular weight ethylene/octene-1 copolymer and its physical properties> A drawn and oriented fiber was prepared by the method described in Example 1. Table 2 shows the tensile properties of the multifilament obtained by bundling a plurality of drawn and oriented fibers. The original crystal melting peak of ultra-high molecular weight ethylene/octene-1 copolymer drawn filament (Sample-2) is 13
At 2.1 °C, the proportions of Tp and Tp1 to the total crystal melting peak area were 97.7% and 5.0%, respectively.
Met. The creep resistance of sample-2 is CR90=2.0
%, ε=9.50×10-6 sec-1. Furthermore, after heat history at 170°C for 5 minutes, the elastic modulus retention was 108.2% and the strength retention was 102.1%. Furthermore, the amount of work required to break sample-2 is 10.1k.
g・m/g, density is 0.971g/cm3, dielectric constant is 2.2, and dielectric loss tangent is 0.031.
%, and the impulse voltage breakdown value is 185kV/m
It was m. The reduction rates of multifilament knot strength and loop strength relative to linear strength are 35% and 3, respectively.
It was 2%.

<Polymerization of ultra-high molecular weight polyethylene> Slurry polymerization of ultra-high molecular weight polyethylene was carried out using a Ziegler catalyst and 1 liter of n-decane as a polymerization solvent. Prior to polymerization, a mixed gas of ethylene gas and hydrogen gas was introduced into the reactor at a pressure of 5 kg/cm2 (partial pressure of hydrogen gas was 0).
．． After that, only ethylene gas was supplied to maintain the polymerization pressure at 5 kg/cm2. Polymerization was completed in 2 hours at a reaction temperature of 70°C. The yield of the obtained ultra-high molecular weight polyethylene was 170 g, and the intrinsic viscosity [η] (decalin: 135°C) was 7.42 dl.
/g.

<Preparation of stretched and oriented ultra-high molecular weight polyethylene> Ultra-high molecular weight polyethylene (homopolymer) powder (intrinsic viscosity [η]=7.42 dl/g, Decalin, 135
°C): 20 parts by weight and paraffin wax (melting point = 69
°C, molecular weight = 490): 80 parts by weight of the mixture in Example 1
Melt-spun, drawn, and drawn oriented fibers (Sample-3)
) was obtained. Table 3 shows the tensile properties of the multifilament obtained by bundling a plurality of drawn and oriented fibers.

The original crystal melting peak of the ultra-high molecular weight polyethylene drawn filament (Sample-3) was 135.1°C;
The ratio of Tp to the total crystal melting peak area is 8.8
%Met. Similarly, the ratio of the high temperature side peak Tp1 to the total crystal melting peak area was 1% or less. Creep resistance is CR
90=11.9%, ε=1.07×10-3sec-1
Met. Further, after heat history at 170°C for 5 minutes, the elastic modulus retention rate was 80.4% and the strength retention rate was 78.2%. Furthermore, the amount of work required to break sample-3 is 10.2k.
g·m/g, the density was 0.985 g/cm3, the dielectric constant was 2.3, the dielectric loss tangent was 0.030%, and the impulse voltage breakdown value was 182 kV/mm. The reduction rates of the knot strength and loop strength of the multifilament with respect to the linear strength were 54% and 52%, respectively.

[0044]

<Coating example of polyolefin layer> L-LDPE (UL made by Mitsui Petrochemical Industries, Ltd.) was coated on the surface of the core material cloth listed in Table 4 using an extrusion laminating device.
TZEX 2081C, MFR =8g/10min
) was extrusion coated to a thickness of 40 μm under the following conditions. Then, the back side was also extruded to a thickness of 40 μm using the same method. As a result, it was possible to obtain a laminate in which the resin layers extrusion coated on both sides of the core material cloth were completely fused, and in addition, no thermal change in the core layer was observed in appearance.

Extrusion lamination conditions Resin extrusion temperature: 280°C Air gap: 130mm Extruded resin laminate thickness (one side): 40μm Lamination speed: 60m/min Cooling roll temperature: 20°C

<Joining of laminate> The stack bonding strength was measured using a heat seal tester under the following conditions. As a result, when bonding with a seal line width of 10 mm or more was performed, the strength of the joint (tensile strength in the shear direction) was equal to or higher than the strength of the base material (film material) (the joint did not break). Note that the same bonding performance can be obtained using a bonding device other than the heat bar type, such as an impulse sealer. Heat sealer: Toyo Tester Heat bar width: 10mm Temperature: 130℃ Time: 2 seconds Pressure: 2kg/cm2

0048
] Table 5 shows the physical properties of the laminate.

Claims (6)

[Claims] Claim 1: The intrinsic viscosity [η] is at least 5 dl/
A core layer is a woven or blended fabric of a molecularly oriented molded product of an ultra-high molecular weight ethylene polymer and one or more types of fibers selected from the group consisting of aramid, polyamide and polyester. A high-strength membrane material that is made of a laminate with a polyolefin resin layer laminated on top and can be easily joined by heat fusion. [Claim 2] The polyolefin resin has a density of 0.9.
0 to 0.94g/cm3, melt index 1
~50g/10min, melting point 110~130
2. The high-strength membrane material according to claim 1, which is a random copolymer of ethylene and an α-olefin having 4 to 10 carbon atoms and having an ethylene content of 90 to 98 mol%. 3. The ultra-high molecular weight ethylene polymer contains ethylene and α-olefin containing on average 0.1 to 20 α-olefins having 3 or more carbon atoms per 1000 carbon atoms.
The high-strength membrane material according to claim 1 or 2, which is an olefin copolymer. 4. The α-olefin is butene-1,4-
4. The high-strength membrane material according to claim 3, which is one or more selected from the group consisting of methylpentene-1, hexene-1, and decene-1. Claim 5: The content of α-olefin is 1 carbon atom.
The high-strength membrane material according to claim 3 or 4, wherein the average number of membranes is 0.5 to 10 per 000 membranes. Claim 6: The intrinsic viscosity [η] is at least 5 dl/
The core layer is a blended fabric of a molecularly oriented molded product of an ultra-high molecular weight ethylene polymer (g) and one or more fibers selected from the group consisting of aramid, polyamide and polyester, and at least one surface thereof A balloon consisting of a laminate or body made of polyolefin resin layers.