JPH02173016A - heat sealant - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a heat sealing agent, and more particularly to a heat sealing agent comprising a propylene polymer having a low melting point and excellent blocking resistance.

Technical background of the invention and its problems Polypropylene has excellent physical properties, so
It is used for a wide range of purposes. For example, polypropylene is widely used as a packaging film, but since polypropylene has a relatively high melting point, in order to improve heat-sealability at low temperatures in this type of application, propylene is generally mixed with ethylene or carbon atoms with 4 to 20 carbon atoms. α−
It is used as a propylene/α-olefin copolymer by copolymerizing olefins.

Conventionally known packaging films made of propylene/α-olefin copolymers have superior transparency and scratch resistance compared to films made of low-density polyethylene, but they still have poor heat sealability at low temperatures. However, there is a desire for a propylene/α-olefin copolymer that has excellent heat sealing properties at low temperatures and can be used as a heat sealing agent.

It is known that in order to improve the heat sealability of the propylene/α-olefin random copolymer described above, it is sufficient to increase the copolymerization amount of ethylene or α-olefin having 4 to 20 carbon atoms with respect to propylene. Although,
If the copolymerization amount of ethylene or α-olefin having 4 to 20 carbon atoms is increased, the resulting propylene/α-
Olefin copolymers have a large amount of solvent soluble content, resulting in poor blocking resistance and poor rigidity.

In order to obtain a propylene polymer with excellent heat sealability, blocking resistance, and rigidity at low temperatures, α
- It is necessary to develop a propylene homopolymer or a propylene random copolymer that has a low melting point even though the amount of copolymerized olefin is zero or small.

Conventionally, olefin polymerization catalysts consisting of titanium or vanadium compounds and organoaluminum compounds have been used to produce propylene homopolymers or propylene/α-olefin random copolymers, but in recent years, new Ziegler-type olefins have been used. Catalysts consisting of zirconium compounds and aluminoxane have recently been proposed as polymerization catalysts.

JP-A No. 58-19309 describes the following formula 1% [where R is cyclopentadienyl, 01 to C6 alkyl, halogen, Me is a transition metal, Ha
fJ is a halogen] and a transition metal-containing compound represented by the following formula %)) [where R is methyl or ethyl and n is 4 to 2
In the presence of a catalyst consisting of a linear aluminoxane represented by the number 0] or a cyclic aluminoxane represented by the following formula [where R and n are the same as above], ethylene and A method is described in which one or more C8 to C12 α-olefins are polymerized at temperatures of -50°C to 200°C. The publication states that in order to adjust the density of the resulting polyethylene, the polymerization of ethylene should be carried out in the presence of small amounts of up to 10% by weight of somewhat long-chain α-olefins or mixtures. .

JP-A-59-95292 describes a linear aluminoxane represented by the following formula, [where n is 2 to 40 and R is C1-C6] and a linear aluminoxane represented by the following formula [where n and R are The invention relates to a method for producing a cyclic aluminoxane represented by [Definition is the same as above]. The publication describes, for example, methylaluminoxane and titanium or zirconium bis(
It is stated that when olefins are polymerized by mixing them with a cyclopentadienyl compound, 25 million g or more of polyethylene can be obtained per 1 g of transition metal per hour.

JP-A No. 60-35005 describes the following formula [where,
an aluminoxane compound in which R is C-C, alkyl, and R is R1 or combined to represent 10- is first reacted with a magnesium compound, and then the reaction product is chlorinated; Furthermore, a method for producing an olefin polymerization catalyst by treatment with a compound of TI, VSZr, or C is disclosed. The publication also discloses that the catalyst is a copolymer of a mixture of ethylene and a C-C12 α-olefin. It is described as being particularly suitable for.

JP-A-60-35006 discloses that two or more different transition metal mono- or tricyclopentadienyl or derivatives thereof (a) and aluminoxane (b) are used as a catalyst system for producing a reactor blend polymer. ) combinations are disclosed. In Example 1 of the same publication, ethylene and propylene were polymerized using bis(pentamethylcyclopentagenyl)zirconium dimethyl and aluminoxane as catalysts, and the number average molecular weight was 15,300, the weight average molecular weight was 36,400, and 3.4% propylene component
It is disclosed that a polyethylene containing polyethylene was obtained. In Example 2, ethylene and propylene were polymerized using bis(pentamethylcyclopentadienyl)zirconium dichloride, bis(methylcyclopentagenyl)zirconium dichloride, and aluminoxane as catalysts, and the number average molecular weight was 2, 200, weight average molecular weight 1
Number average molecular weight 2 consisting of a toluene soluble portion containing a propylene component of 1.900 and 30 mol% and a toluene insoluble portion containing a propylene component with a number average molecular weight of 3.000 and a weight average molecular weight of 7,400 and 4.8 mol%. ,000
, a blend of polyethylene and ethylene-propylene copolymer having a weight average molecular weight of 8.300 and a propylene component of 7.1 mol % was obtained. Similarly, Example 3
The composition is made of LLDPE and ethylene-propylene copolymer consisting of a soluble portion with a molecular weight distribution (Mv/un) of 4.57 and a propylene component of 20.6%, and an insoluble portion with a molecular weight distribution of 3.04 and a propylene component of 2.9 mol%. Blends are listed.

JP-A No. 60-35007 discloses that ethylene alone or together with an α-olefin having 3 or more carbon atoms is used with metallocene and the following formula [where R is an alkyl group having 1 to 5 carbon atoms, and n is 1 in the presence of a catalyst system comprising a cyclic aluminoxane represented by A method for polymerization is described.

According to the description in the same publication, the polymer obtained by this method has a weight average molecular weight of about 500 to about 1.4 million, and a molecular weight distribution of 1.5 to 4.0.

In addition, JP-A-60-35008 discloses that by using a catalyst system containing at least two types of metallocene and aluminoxane, polyethylene or ethylene having a wide molecular weight distribution of 111 and α-olefin of 03 to C1o can be combined. It is described that polymers are produced. The publication states that the above copolymer has a molecular weight distribution (My/Mn) of 2 to
50.

Furthermore, JP-A-61-130314 discloses that polypropylene with a high degree of isotacticity can be obtained by polymerizing propylene in the presence of a catalyst system consisting of a sterically fixed zircon-chelate compound and aluminoxane. Are listed.

Furthermore, J,AIl,CheIl,Soc,, 109
．． 6544 (1987), when propylene is polymerized in the presence of a catalyst system consisting of ethylene bis(indenyl) hafnium dichloride or its hydride and aluminoxane, high molecular weight isotactic polypropylene is produced, and its molecular weight distribution ( My/Mn) is 2.1 to 2.
It is stated that it is narrow as 4.

On the other hand, Japanese Patent Application Laid-Open No. 63-142005 discloses that M
It is described that stereoblock polypropylene having a y/Mn of 5.0 to 14.9 can be obtained. The propylene obtained here is a rubbery polymer with a short isotactic chain length.

The present inventors have demonstrated the ability to homopolymerize propylene or copolymerize propylene with ethylene and/or an α-olefin having 4 to 20 carbon atoms in the presence of an olefin polymerization catalyst consisting of a specific hafnium compound and aluminoxane. When polymerized, a propylene polymer with a lower melting point than conventionally known propylene homopolymers or propylene/a-olefin copolymers can be obtained, and this propylene polymer has excellent properties as a heat sealing agent. The present invention was completed based on the discovery that the present invention has the following properties.

Purpose of the Invention The present invention aims to solve the above-mentioned problems in the prior art. The purpose of the present invention is to provide a heat sealing agent made of a propylene polymer.

Summary of the Invention The heat sealing agent according to the present invention comprises (A) a propylene component in an amount of 90 to 100 mol%, an ethylene component in an amount of 0 to 10 mol%, and a carbon number of 4 to 100%;
CB) melting point [T11] measured by differential scanning calorimeter;
However, 70 Tm<155-5.5 (100-P) (in the formula P
is the propylene component content (mol%) in the polymer), and (C) the intrinsic viscosity [η] measured in decalin at 135°C
is in the range of 0.5 to 6 dl/lr, and (D) is composed of a propylene polymer having an amount of boiling trichlorethylene insoluble content of 5% by weight or less.

DETAILED DESCRIPTION OF THE INVENTION The heat sealing agent according to the present invention will be specifically explained below.

The heat sealing agent according to the present invention is made of a propylene polymer, in which the propylene component is present in an amount of 90 to 100 mol%, preferably 92 to 99 mol%, and the ethylene component is present in an amount of 90 to 100 mol%, preferably 92 to 99 mol%. The α-olefin component is present in an amount of 0 to 10 mol%, preferably 0.5 to 9.5 mol%, and is derived from an α-olefin having 4 to 20 carbon atoms, and is present in an amount of 0 to 10 mol%, preferably 0.5 ~9.5 mol%
is present in an amount of

A propylene-based polymer in which the propylene component is 100 mol % is a propylene homopolymer.

Further, the propylene-based polymer having an ethylene component of 0 mol % is a propylene/α-olefin random copolymer consisting of propylene and an α-olefin having 4 to 20 carbon atoms. Further, a propylene polymer in which the α-olefin component derived from an α-olefin having 4 to 20 carbon atoms is 0 mol % is a propylene/ethylene random copolymer.

Furthermore, a propylene polymer in which neither the ethylene component nor the α-olefin component is 0 mol % is a propylene/ethylene/α-olefin random copolymer.

In the propylene-based polymer as described above, if the propylene component is less than 90 mol%, the blocking resistance and rigidity of the heat sealing agent tend to be poor.

The α-olefins having 4 to 20 carbon atoms used in the present invention include ■-butene, l-pentene, l-hexene,
-Methyl-1-pentene, 3-methyl-■-pentene,
1-octene, l-decene, ■-dodecene, ■-tetradecene, ■-hexadecene, ■-octadecene, l-eicosene, etc. are used. Among these, 1-butene is particularly preferred.

The propylene homopolymer or propylene random copolymer according to the present invention has a melting point [TIl] measured by a differential scanning calorimeter of 70<Tm<155-5.5 (100-P), preferably 90<Tm< 150-5.5 (100-P) (in the formula P
is the propylene component in the copolymer (mol %).

A schematic relationship between the melting point TII of such a propylene homopolymer or propylene copolymer and the propylene component content P mol % in the copolymer is shown as a straight line A in FIG. In addition, in FIG. 1, the relationship between the melting point Tm of a conventionally known propylene copolymer and the propylene component content P mol % is also shown as a straight line B.

As is clear from FIG. 1, the melting point of the propylene homopolymer or propylene copolymer according to the present invention is
When the copolymerization amounts of ethylene and/or α-olefin are the same, the melting point is 10 to 20° C. lower than the melting point of conventionally known propylene random copolymers. Therefore, the film obtained from the propylene polymer according to the present invention is
It has excellent heat sealability especially at low temperatures. Moreover, since the copolymerized amount of ethylene and/or α-olefin exhibits excellent heat sealability, it also has excellent blocking resistance and, moreover, excellent rigidity.

In the present invention, using a differential scanning calorimeter (D SC), the propylene polymer was left at 200°C for 5 minutes, then cooled to 20°C at a rate of 10°C/min, and then heated to 20°C.
After leaving for 5 minutes at 20°C at 10°C/min.
The temperature of the maximum endothermic peak obtained by measuring up to 00°C (T
s ) was taken as the melting point of the propylene polymer.

In the present invention, such a propylene-based polymer exhibits excellent heat-sealing properties, blocking resistance, and rigidity as described above, and is used as a heat-sealing agent.

In the present invention, the heat sealing agent made of the propylene polymer as described above can be used, for example, in the form of a film and laminated with another film. Furthermore, since the propylene-based polymer as described above also has excellent heat-sealing properties, it can be blended with other polyolefins and used as a heat-sealing property-imparting agent.

Furthermore, the molecular weight distribution (My/Mn) of the propylene polymer according to the present invention determined by gel permeation chromatography (GPC) is in the range of 3.5 or less, preferably 3 or less, particularly preferably 2.5 or less. be. As described above, the propylene polymer according to the present invention has a narrow molecular weight distribution,
Also from this point of view, it has excellent blocking resistance.

The My/Mn value was determined as follows based on "Gel Vermeation Chromatography" written by Takeuchi and published by Maruzen.

(1) Using standard polystyrene with a known molecular weight (manufactured by Toyo Soda ■, monodisperse polystyrene), calculate the molecular weight M and its G.
P C (Get Permeatophon Chros)
atograph) counts and molecular weights M and E
A correlation diagram calibration curve of V (Elutron Vo Iume) is created. The concentration at this time is 0.02% by weight.

(2) Take a GPC chromatograph of the sample using G P CilP + constant, calculate the number average molecular weight JIMn and weight average molecular weight Mv in terms of polystyrene according to the above (1),
Find the Mv/FiiIn value. The sample preparation conditions and G P CC1 constant conditions at that time are as follows.

[Sample Preparation] (a) Disperse the sample in an Erlenmeyer flask together with 0-dichlorobenzene solvent to a concentration of 0.1% by weight.

(b) Heat the Erlenmeyer flask to 140°C and stir for about 30 minutes to dissolve.

(c) Subject the solution to GPC.

[GPC measurement conditions] It was conducted under the following conditions.

(a) Equipment Manufactured by Waters (150cmAL
C/GPC) (b) Column manufactured by Toyo Soda (GMH
Type) (c) Sample amount 400 μg (d) Temperature 140°C (e) Flow rate 1 ml/min The melting point was measured using Perkin EIIIler-7 type D.
IpI was determined using an SC device with a sample quantity of 2.5 mg and a heating rate of 10° C./min.

Further, it is desirable that the propylene polymer according to the present invention has a soluble portion in boiling n-pentane of 5% by weight or less, preferably 3% by weight or less, and more preferably 2% by weight or less.

Furthermore, it is desirable that the propylene polymer according to the present invention has an insoluble portion in boiling trichlorethylene of 5% by weight or less, preferably 3% by weight or less, and more preferably 1% by weight or less.

To determine the amount of boiling trichlorethylene insoluble matter and boiling n-heptane soluble matter, put 3 g of a finely ground sample into a thimble filter paper, extract with a Soxhlet extractor using 180 ml of solvent for 5 hours, and dry the extracted residue to a constant weight with a vacuum dryer. The amount of ffi was determined by drying until the weight of the original sample was reached.

The propylene polymer according to the present invention as described above comprises (A) a polydentate compound in which at least two groups selected from cycloalkagenyl groups or substituents thereof are bonded via a lower alkylene group. In the presence of a hafnium compound as a ligand and a catalyst formed from (B) aluminoxane, propylene and a carbon atom having a carbon number of 4
~20 α-olefins can be produced by homopolymerizing propylene or copolymerizing propylene with ethylene and/or α-olefins.

The catalyst component [A] used in the present invention is a cycloalkagenyl group or a substituted product thereof, specifically, at least two groups selected from the group consisting of an indenyl group, a substituted indenyl group, and a partially hydrogenated product thereof. It is a hafnium compound whose ligand is a polydentate compound in which groups are bonded via lower alkylene groups. The following compounds can be exemplified as the hafnium compound.

Ethylenebis(indenyl)dimethylhafnium, ethylenebis(indenyl)diethylhafnium, ethylenebis(indenyl)diphenylhafnium, ethylenebis(indenyl)methylhafnium monochloride, ethylenebis(indenyl)ethylhafnium monochloride, ethylenebis(indenyl)methyl hafnium monopromide, ethylene bis(indenyl) hafnium compound lide, ethylene bis(indenyl) hafnium compound lide, ethylene bis(4,5,6,7-tetrahydro-l-indenyl) dimethyl hafnium, ethylene bis(4, 5,6,7-tetrahydro-1-indenyl)methylhafnium monochloride, ethylenebis(4,5,6,7-tetrahydro-1-indenyl)
Hafnium dichloride, ethylene bis(4,5,8,7-tetrahydro-1-indenyl) hafnium dichloride, ethylene bis(4-methyl-1-indenyl) hafnium dichloride, ethylene bis(5-methyl-1-indenyl) hafnium dichloride , Ethylenebis(6-methyl-1-indenyl)hafnium dichloride, Ethylenebis(7-methyl-■-indenyl)hafnium dichloride, Ethylenebis(5-methoxy-1-indenyl)hafnium dichloride, Ethylenebis(2,3- dimethyl-1-indenyl) hafnium dichloride, ethylenebis(4,7-dimethyl-1-indenyl)hafnium dichloride, ethylenebis(4,7-simethoxy-1-indenyl)
Hafnium dichloride.

The catalyst component [B] used in the method of the invention is an aluminoxane. Examples of the aluminoxane used as a catalyst component include oxyorganoaluminum compounds represented by the general formula (1) and the following formula (n). In the aluminoxane, R is a hydrocarbon group such as a methyl group, ethyl group, propyl group, or butyl group, preferably a methyl group or an ethyl group, particularly preferably a methyl group, and m is 2 or more, preferably It is an integer greater than or equal to 5. Examples of the method for producing the aluminoxane include the following method.

(1) Compounds containing adsorbed water, salts containing water of crystallization, such as magnesium chloride hydrate, copper sulfate hydrate, aluminum sulfate hydrate, nickel sulfate hydrate, monochloride
A method of adding trialkylaluminium to a suspension in another hydrocarbon medium such as cerium hydrate and causing a reaction.

(2) A method in which water, steam, or ice is directly applied to trialkylaluminum in a medium such as benzene, toluene, ethyl ether, or tetrahydrofuran.

Note that the aluminoxane may contain a small amount of organometallic component.

The hafnium compound as described above is used in an amount of usually 10-8 to 10 g atoms/g, preferably 10-7 to 10-3 g atoms/g as the concentration of hafnium atoms in the polymerization reaction system. is desirable.

Further, the aluminoxane as described above is used in an amount of 10-4 to 10-1 gram atoms/g, preferably 5×10-' to 5×10-2 gram atoms/g in terms of aluminum atoms in the reaction system. It is desirable that it be used.

The polymerization temperature is usually 40 to 100°C, preferably 45 to 9°C.
It is desirable that the temperature is 5°C, more preferably in the range of 50 to 90°C.

The polymerization of olefins as described above is usually carried out in a gas phase or a liquid phase. In liquid phase polymerization, an inert hydrocarbon may be used as a solvent, or the olefin itself may be used as a solvent.

Hydrocarbon media specifically include butane, isobutane, pentane, hexane, octane, decane, dodecane,
Aliphatic hydrocarbons such as hexadecane and octadecane,
Alicyclic hydrocarbons such as cyclopenkune, methylcyclopenkune, cyclohexane, and cyclooctane, aromatic hydrocarbons such as benzene, toluene, and xylene, and petroleum fractions such as gasoline, kerosene, and kerosene are used.

The polymerization pressure is usually normal pressure to 100 kg/c, preferably normal pressure to 50 kg/cd, and the polymerization can be carried out in any of the batch, semi-continuous, and continuous methods. The molecular weight of the polymer can be controlled by hydrogen and/or polymerization temperature.

Effects of the Invention According to the present invention, there is provided a heat sealability imparting agent made of a propylene polymer having a lower melting point than conventionally known propylene polymers, and this heat sealability imparting agent has excellent heat sealability. In addition to having sealing properties, it also has excellent blocking resistance and rigidity.

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

Example 1 (Preparation of methylaluminoxane) Polymer Co., 29, 180 (198
8).

(Synthesis of ethylene bis(indenyl) hafnium dichloride) Bis(indenyl)ethane (Bill, Soc, Cblm,
, 2954 (1967) I: based synthesis) 5.4 g
and 50 ml of THF and heated to -30 to -4 while stirring.
Cooled to 0'C. To this, n-Bu Ll (1,
Add 31.5 ml of 6M solution, and then heat to -30'C.
After stirring for 1 hour, bis(indenyl)ethane was anionized by naturally raising the temperature to room temperature. Add THF60 to another 200 ml glass flask purged with nitrogen.
After cooling to below -60℃, Hf'(16,7
g was gradually added. Thereafter, the temperature was raised to 60°C and stirred for 1 hour. An anionized ligand is added dropwise to this, and 6
After stirring at 0"C for 2 hours, it was filtered through a glass filter. The filtrate was concentrated at room temperature to an initial volume of about 115%. This operation precipitated a solid. After filtering this precipitated solid through a glass filter, it was diluted with hexane/ The target compound was obtained by washing with ethanol and drying under reduced pressure.

(Polymerization) 750 ml of toluene was charged at room temperature into a 2 g stainless steel autoclave which had been sufficiently purged with nitrogen to saturate the propylene gas. Next, add methylaluminoxane to Al,
1.88×10 mol of ethylenebis(indenyl)hafnium dichloride-3, which was 7.5 milligram atoms in terms of atoms, was added. Total pressure 7 kg/c-・ while continuously supplying propylene gas
Polymerization was carried out at 50° C. for 0.5 h under G. Polymerization was stopped by adding methanol to the polymerization system. The resulting polymer slurry was poured into a large amount of methanol, recovered by filtration, and the catalyst component was removed using an isobutyl alcohol/hydrochloric acid solvent. Thereafter, by drying under reduced pressure at 80°C and 200 to 300 mmHg overnight, Fiilv/Mn by CPC was 1.8.
9, the melting point by DSC is 132°C, and 135
[η] measured in decalin at ℃ is 2.82 djl/+
r, and the amount of boiling trichlorethylene insoluble matter is 0% by weight.
1 g of isotactic polypropylene 107 having a boiling n-hebutane soluble content of 0.2% by weight was obtained.

Example 2 (Polymerization) 500 ml of toluene, 3 moles of propylene, 0.1 mole of l-butene, and 5 milligrams of methylaluminoxane (calculated as AII atoms) were charged at room temperature into a 21 stainless steel autoclave which was sufficiently purged with nitrogen. did. Thereafter, the inside of the polymerization system was cooled to 45 DEG C., 1.25.times.10@-3 mmol of ethylene bis(indenyl) hafnium dichloride was added, and polymerization was carried out at 50 DEG C. for 0.5 hour. Polymerization was stopped by adding methanol to the polymerization system.

The resulting polymer slurry was poured into a large amount of methanol, recovered by filtration, and the catalyst component was removed with an isobutyl alcohol/hydrochloric acid solution. After that, 8
When dried under reduced pressure overnight at 0°C with 11 g of 200-300 mm, the -butene content was 2.2 mol%, and the temperature was 135°C.
[η] determined by δIII in decalin is 3.02d#/
g, the melting point by DSC is 124°C, the amount of boiling trichlorethylene insolubles is 0% by weight, and the boiling n-
A polyurethane material having a pentane soluble content of 0.3% by weight and a Mw/Mn of 2.41 by GPC. -27.5 g was obtained.

Example 3 Polymerization was carried out in the same manner as in Example 2, except that the amount of ■-butene charged was 0.25 mol, and the l-butene content was 5.6 mol%. η] is 2
．． 95dj! /g, melting point is 116°C, boiling trichlorethylene insoluble content is 0% by weight, boiling n
- Pentane soluble content is 0.4% by weight, My /M
29.1 g of polymer with n=2.33 were obtained.

Example 4 A mixed gas was prepared so that the propylene, -butene and ethylene gas compositions were 96.7.2.1.1.2 mol%, respectively. Pour 500 ml of toluene into a 2 g stainless steel autoclave that has been sufficiently purged with nitrogen, and heat to 0°C.
After the mixture was cooled to a temperature of 100.degree. C., 3 moles of the above-prepared mixed gas and 5 milligrams of methylaluminoxane (calculated as Ag atoms) were charged. Thereafter, the temperature inside the polymerization system was raised to 45°C, and ethylene bis(indenyl) hafnium dichloride was added to 1.
25×10 3 mol was added and polymerization was carried out at 50° C. for 0.5 hour. Polymerization was stopped by adding methanol to the polymerization system.

The resulting polymer slurry was poured into a large amount of methanol, recovered by filtration, and the catalyst component was removed with an isobutyl alcohol/hydrochloric acid solution. After that, 8
When dried under reduced pressure at 0°C and 200 to 300 wHg overnight, the l-butene content was 1.4 mol%, the ethylene content was 1.1 mol%, and [η] measured in decalin at 135°C was 3.32 clll/g, the melting point by DSC is 121°C, the amount of boiling trichlorethylene insolubles is 0% by weight, and the amount of boiling n-pentane solubles is 0.
9% by weight, and Kitv/Mn by GPC is 2.
51.3 g of polymer No. 45 were obtained.

Example 5 Polymerization was carried out in the same manner as in Example 4, except that the molar ratio of propylene, 1-butene and ethylene was 95.1/3.9/1.0. is 2.7 mol%, and the ethylene content is 0.8 mol%
, [η] is 3.29 dN/g, and the melting point is 11
Polymer 48.5s whose temperature is 8°C, the boiling trichlorethylene insoluble content is 0% by weight, the boiling n-penkun soluble content is 1.1% by weight, and My/Mn is 2.40.
r was obtained.

Example 6 Propylene and ethylene gas compositions are each 98.5
．． A mixed gas was prepared to have a concentration of 1.5 mol%. The subsequent operations were carried out in the same manner as in Example 4, and the ethylene content was 1.3 mol%, and [η] was 3.50 dR/g.
53.3 g of a polymer having a melting point of 125° C., a boiling trichlorethylene insoluble content of 0% by weight, a boiling n-pentane soluble content of 1.0% by weight, and a My/Mn of 2.39. was gotten.

Evaluation Example The heat sealability of the propylene polymer obtained in the example was evaluated as follows.

Preparation of Film Place an aluminum sheet with a thickness of 0.1a + m on a press board, a polyester sheet (manufactured by Toshi Co., Ltd., product name: Lumirror), and a polyimide resin sheet with a thickness of 50 μm (manufactured by DuPont) with a 15cm x 15cm square cut out in the center. (trade name: Kapton) sheets were laid out in this order, and 0.8 g of the sample was placed in the center (cutout part). Next, Lumirror ■
Layer the aluminum plates and press plates in this order (Figure 2)
).

The sample sandwiched between the press plates was placed in a hot press at 200°C, and after preheating for approximately 5 minutes, pressure was applied (20 kg/cd・G) to remove air bubbles within the sample.
Repeat the depressurization operation three times. Then finally 150kg/c
Increase the pressure to C/G and heat under pressure for 5 minutes. After removing the pressure, the press plate was taken out of the press, transferred to a separate press whose crimped portion was maintained at 30°C, and cooled under pressure at 100 kg/c- for 4 minutes, then the pressure was removed and the sample was taken out. Among the obtained films, a film having a uniform thickness of 50 to 70 μm is used as a film for the following measurement.

Measurement of heat seal strength The film prepared by the method described above is placed in a constant humidity layer at 50°C for 2 days (aging). Regarding aging,
Place paper on both sides of the film to prevent the films from touching each other. The film subjected to the above aging is 15
Cut into strips with a width of mm, stack the two pieces on top of each other, sandwich the two pieces with a thickness of 0.1 mm between Teflon films, and heat-seal them on top. Heat sealing is carried out by keeping the temperature at the bottom of the heat sealer hot plate constant at 70°C and changing only the temperature at the top of the hot plate in 5°C increments.

The pressure during heat sealing was 2 kg/cd, the heat sealing time was 1 second, and the sealing width was 5 mm (therefore, the sealing area was 15 m x 5 mm).

The heat-sealing strength is determined by conducting a tensile test on the peel strength of the film heat-sealed at each of the above-mentioned heat-sealing temperatures at a tensile speed of 30 cm/min. (
(See Figure 3).

The peel strength at each heat-sealing temperature in 5°C increments is determined by the method described above, and the plot of heat-sealing temperature versus peel strength is connected by a curve. Based on this curve 800 g/15
The heat-sealing temperature that gives a peel strength of an is defined as the complete heat-sealing temperature (see FIG. 4).

Table 1 shows the complete heat sealing temperatures of the propylene polymers obtained in each example.

Table 1

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between the propylene content and melting point of the propylene polymer according to the present invention. In addition, in FIG. 1, straight line A shows the relationship between the propylene content and melting point of the propylene polymer according to the present invention,
Straight line B shows the relationship between propylene content and melting point of conventionally known propylene polymers. Furthermore, FIGS. 2 to 4 are diagrams showing a method for evaluating heat sealability of a propylene polymer according to the present invention. FIG. 5 is a flowchart for producing a propylene copolymer according to the present invention.

Claims (1)

[Claims] 1) (A) Derived from an α-olefin having a propylene component of 90 to 100 mol%, an ethylene component of 0 to 10 mol%, and a carbon number of 4 to 20. The α-olefin component is present in an amount of 0 to 10 mol%, and (B) the melting point [Tm] measured by differential scanning calorimeter is 70<Tm<155-5.5(100-P) (in the formula P is the propylene component content (mol%) in the polymer), and (C) the intrinsic viscosity [η] measured in decalin at 135°C
is in the range of 0.5 to 6 dl/g, and (D) a heat sealing agent comprising a propylene polymer having an amount of boiling trichlorethylene insoluble content of 5% by weight or less.