JPS62101615A - Production of modified ethylene/alpha-olefin copolymer composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition excellent in moldability and vulcanization bondability to fiber and useful in fiber-reinforced belts, by reacting a compound having a polar group with a specified copolymer in the presence of an organic radical generator. CONSTITUTION:100pts.wt. ethylene/alpha-olefin copolymer having a bimodal MW distribution, an area of the lower MW portion of 10-50% based on the entire area, a weight-average MW to number-average MW ratio of 5-25 and an alpha-olefin content of 20-60wt% is mixed with 0.01-2pts.wt. organic radical generator such as benzoyl peroxide and 0.05-50pts.wt. polar group-containing compound such as acrylic acid. The mixture is reacted by kneading at 50-300 deg.C for 0.5min-10hr to obtain a modified ethylene/alpha-olefin copolymer composition.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a modified ethylene-α-olefin copolymer composition that has good moldability when unvulcanized and has excellent vulcanization adhesion to fibers. Concerning the manufacturing method.

More specifically, it is an ethylene-α-olefin copolymer composition modified with a compound having a polar group using an organic radical generator, which has excellent moldability in an unvulcanized state, and which is suitable for use with nylon, polyester, etc. The present invention relates to a method for producing a modified ethylene-α-olefin copolymer composition that has excellent strength and adhesive properties through a vulcanization process of the composition when used as a composite material with fibers of the present invention.

Specific applications include fiber-reinforced heat-resistant conveyor belts, fiber-reinforced belts, and fiber-reinforced diaphragms, and can be applied to composites of various fibers and rubber.

[Prior art]

Since the ethylene-α-olefin copolymer is a hydrocarbon polymer, even when trying to obtain a composite with fibers, there is no interaction with the fibers, and a peeling phenomenon occurs at the interface, making it difficult to obtain a good composite. do not have. Therefore, measures have been taken to prevent the interfacial cracking phenomenon by mixing various adhesives into the copolymer and applying surface treatments to the fibers, but no satisfactory results have been obtained.

[Problem that the invention seeks to solve]

Ethylene-α-olefin copolymers are hydrocarbon polymers that do not have temporary groups in their molecules, so they do not interact with various fibers and can be used as composites of copolymers and fibers. I can't. On the other hand, ethylene-α-
A modified ethylene-α-olefin copolymer obtained by adding a compound having a polar group to an olefin copolymer using an organic peroxide has a polar group and has the ability to interact with fibers. , it can be expected that a good composite will be obtained.

However, modified ethylene-α- obtained by a generally known method
Olefin copolymers have the disadvantage that they form some gel (three-dimensional crosslinked product) during modification and have poor moldability when unvulcanized.

[Means for solving problems]

In view of the above circumstances, the present inventors have developed a modified ethylene resin that has excellent moldability when unvulcanized and excellent vulcanization adhesion to fibers.
As a result of our earnest efforts to obtain an α-olefin copolymer, we found that by using an ethylene-α-olefin copolymer used for modification that had a bimodal molecular weight distribution, moldability when unvulcanized was improved. The present invention was achieved based on the discovery that an excellent product can be obtained and the adhesion to fibers is excellent.

The present invention will be explained in detail below.

Does the ethylene-α-olefin copolymer used in the present invention have a bimodal molecular weight distribution? The area outside the low molecular layer is 10 to 50 percent of the total area, preferably 15 to 4 percent.
0, a weight average molecular weight of 50,000 to 1,000,000, preferably 100,000 to 800,000, and a weight average molecular weight/number average molecular weight of 5 to 25, preferably 6 to 15. The ethylene-α-olefin copolymer may be one or more α-olefins selected from ethylene and α-olefins having 3 or more carbon atoms, such as propylene, butene-1, hexene-1, and octene-1. A copolymer obtained by copolymerizing an olefin or one or more nonconjugated dienes selected from ethylidene norbornene, dicyclopentadiene, 1,4-hexadiene, etc. used.

Among these, ethylene-propylene copolymer, ethylene-butene-1 copolymer, ethylene-propylene-nonconjugated diene copolymer, and ethylene-butene-1-nonconjugated diene copolymer are preferred, and α-olefin content As for 2
A weight ratio of 0 to 60 is preferred.

This paramodal ethylene-α-olefin copolymer can be produced, for example, by the one-stage polymerization method described in Patent Application No. 103,827 of 1985, or by blending.

The compound having two polar groups used in the present invention is a compound containing a group such as a carboxyl group or a carboxylic acid ester residual dimethylchlororane group, and may be a monomer or a polymer.

Specifically, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, vinylbenzoic acid, vinyl phthalic acid, methyl methacrylate, maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid monomethyl ester, fumaric acid monomethyl ester , maleic anhydride, itaconic anhydride, acrylamino, maleimide,
Acrylamide, glyc7dyl methacrylic V-), N-phenylmaleimide, methacrylic acid amide, allyl alcohol, dimethylvinylchloro7rane, 2-trichloro//
Monomers such as lylbutadiene and 2-ethoxysilylbutadiene, ethylene-maleic anhydride copolymer, styrene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, stilbene-maleic anhydride copolymer,
Acrylonitrile-maleic anhydride copolymer, allyl acetate-maleic anhydride copolymer, methyl acrylate-maleic anhydride copolymer, methyl methacrylate-
Polymers such as maleic anhydride copolymer, vinyl acetate-maleic anhydride copolymer, vinyl chloride-maleic anhydride copolymer, and derivatives thereof (hydrolysis products, C
Examples of the organic radical generator used in the present invention include benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl leno(-oxide, di-tert
-butylno(-oxide, 2,5-dimethyl-
2,5-di(haroginbenzoate)hexine-, 3
, 1,4-bis(tert-butylperoxyisopropyl)benzene, lauroyl peroxide, ter
t-Butyl peracetate, 2,5-dimethyl-2,5
-di(veroxybenzoate)hexyne-3, 2.5
-dimethyl-2,5-di(tert-butylperoxy)hexane, tert-butylperisobutyrate,
Examples include tert-butyl bar Sec-octoate, azobisisobutyronitrile, dimethyl azoisobutyrate, and among these, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di(tert
-butylperoxy7)hexane, 1.4-bis(te
rt-butylperoxyisopropyl)benzene is preferred.

The modified ethylene-α-olefin copolymer composition of the present invention has the above-mentioned bimodal molecular weight distribution.
0.05 to 50 parts by weight of a compound having a polar group is added to 100 parts by weight of the α-olefin copolymer, preferably 0.05 to 50 parts by weight.
1 to 10 parts by weight, 0.01 to 2 parts by weight of an organic radical generator
Part by weight preferably 0.05-0. It is obtained by acting in the presence of 5 parts by weight. If the amount of the compound having a polar group is less than 0.05 parts by weight, the peel strength during vulcanization adhesion will not be sufficient, and if it still exceeds 50 parts by weight, the obtained modified ethylene-α-olefin copolymer composition will have a resinous property. On the other hand, the organic radical generator is 0.01
If it is less than 2 parts by weight, the degree of modification of the resulting modified ethylene-α-olefin copolymer composition will be low, and a large amount of compounds having unreacted polar groups will remain in the composition, which is undesirable.
If the amount exceeds parts by weight, three-dimensional crosslinking of the resulting modified ethylene-α-olefin copolymer composition will progress, resulting in poor moldability, which is not preferable.

In producing the modified ethylene-α-olefin copolymer composition of the present invention, a predetermined Wc' of an ethylene-α-olefin copolymer having a bimodal molecular weight distribution, a compound having a polar group, and an organic peroxide is used. fr-
After weighing and mixing using a known method such as a Henschel mixer, -blender, ribbon blender, tumbler blender, etc., kneading in a molten state using a Banbury, kneader, continuous kneader, extruder, etc., or The ethylene-α-olefin copolymer, a compound having a polar group, and an organic peroxide are charged into a reaction vessel such as an autoclave, and then mixed with toluene, xylene, and a carbon number of 1 to 6.
Examples include a method in which the compound is dissolved in a halogenated hydrocarbon solvent, an organic solvent such as tetrahydrofurano, and reacted at a predetermined temperature for a predetermined period of time. The kneading temperature or reaction temperature and the kneading time or reaction time vary depending on the decomposition temperature of the organic radical generator used, so they cannot be unconditionally defined, but are generally 50 to 300°C, preferably 70 to 250°C,
A range of 0.5 minutes to 10 hours, preferably 2 minutes to 5 hours, is used.

In carrying out the present invention, various rubber compounds such as phenol-based, amino-based, phosphorus-based anti-aging agents, carbon, fillers such as inorganic fillers, softeners, plasticizers, zinc white, and stearic acid are used. Can be used together. It is preferable to use an anti-aging agent together.

For the vulcanization of the modified ethylene-α-olefin copolymer composition of the present invention, a conventional crosslinking method for ethylene-α-olefin copolymers can be applied.

For example, peroxide crosslinking, sulfur crosslinking, resin crosslinking, etc. can be applied.

The modified ethylene-α-olefin copolymer composition of the present invention is useful as a fiber-reinforced composite, and can be used, for example, in heat-resistant conveyor belts, belts, diacrums, radiator hoses, heater hoses, etc. can.

In order to use the composition of the present invention for heat-resistant conveyor belts, the composition shown in Example 1 is kneaded, and then a laminate of a rubber layer and a fiber layer is formed by calendering or the like. By methods such as vulcanization.

In addition, for use in radiator hose applications, the composition of the present invention obtained using an ethylene-propylene-nonconjugated diene copolymer as a base polymer is heat-treated with modified silicone oil, and the compounding formula as described below is prepared. After kneading, a laminate of a rubber layer and a fiber layer is formed using a two-layer extruder or the like, and a mandrel is inserted and vulcanization is performed in a can, or normal vulcanization is performed.

<Composition formulation for radiator hose - example> Polymer io.

FEF black (N-550) 150 paraffin oil 100 zinc oxide
5 Stearic acid 1 Vulcanization accelerator MBT, 1'TM
TD 1.5IT MTM
1.5' EZ 1.5 Parunok R
1 Acting SL l, 5 total
365 Still, the preparation of the compound is carried out using open roll mills, Banbury mixers, kneaders, etc.
A known method using, for example, can be adopted.

〔Example〕

Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to the Examples unless it exceeds the scope of the claims.

In addition, in principle, units and parts in the examples are based on weight unless otherwise specified.

In addition, in the examples, various analysis methods and physical property measurement methods were in accordance with the following methods.

(f) Mw/Mn (Weight average molecular weight/number average molecular weight) Measured as follows according to Takeuchi, Körper Mini-7, Jonkrum Matkraft, Marukubi ■.

■ Standard polystyrene with known molecular weight (manufactured by Toyo Soda ■,
using monodisperse polystyrene), the molecular weight M and its GP
C (Gel Permeation Chroma-t
ograph) counts and molecular weight M and EV (
Plot the entire correlation chart calibration curve for Elution Volume).

The concentration at this time is 0.02 weight ratio.

The standard polystyrene calibration curve is corrected to the EPDM calibration curve using the universal method.

(2) Obtain a GPC pattern of the sample using the GPC measurement method and find out M from the above (2). The sample preparation conditions and GPC measurement conditions at that time are as follows.

Sample preparation (a) Add 0.0 of 2.6-di-t-butyl-p-cresol as an anti-aging agent to O-dichlorobenzene solvent.
Add one to 8% and dissolve.

(b) Aliquot the sample into an Erlenmeyer flask together with 0-dichlorobenzene solvent to a ratio of 0.1.

(c) Heat the Erlenmeyer flask to 120°C and stir for about 60 minutes to dissolve.

(a) Apply the solution to GPC. In addition, GPC
The sample is automatically filtered using a 0.5 μm sintered filter within the device.

GPC measurement conditions (a) Apparatus; Model 150C manufactured by Waters (
b) Column; H type manufactured by Toyo Tonda ■ (c) Sample amount: 500 μt (d) Temperature: 120°C (e) Flow rate: 1 mA/min (f) Column b number of theoretical plates: 1X10' to 2X10'
(Measurement value using acetone) (2) A value (value representing the ratio of low molecular weight peaks) From the above molecular weight distribution measurement data, the horizontal axis shows min-F-ft,
A molecular weight distribution map is created by plotting the polymer concentration on the vertical axis.

In addition, at this time, the area of molecular weight distribution is normalized so that it is always constant.

The normalized molecular weight distribution map is separated into two waveforms using a Gaussian function, the area on the low molecular weight side is defined as kWl, and the area on the high molecular weight side is defined as W2, and the A value is determined based on the following equation.

(3) Mooney viscosity (ML, +1100°C) was measured at a temperature of 100°C, with 1 minute of preheating and 4 minutes of measurement.

(4) Propylene content is measured by infrared absorption spectrum. (5) Iodine value is measured by titration method.

(6) Tensile strength, elongation, tensile stress, hardness are JIS K
Measured based on 2SO3.

(7) Molding processability was evaluated by extrusion processability of the compound.

Extrusion processability is based on ASTM D-2230, tube type (diameter: 50 mm, screw temperature: 70°C, head temperature: 100°C, rotation speed: 3 Orpm, using a garbet tie)
An extrusion test was conducted and the extrusion amount, shape, and die swell were measured.

(8) In the fiber adhesion test, nylon treated with RFL (Resol/Nol, Formaldehyde, Latex) liquid was used as the fabric layer, and the fabric layer was first sandwiched between unvulcanized rubber sorts, air was expelled with a manual roller, and a peel test was performed. At times, the parts to be gripped are filled with cellophane in advance to prevent adhesion, and a press-vulcanized fiber-reinforced rubber composite sort is made. Next, use this Sortra cutting machine to cut the width to 25mm.
Peeling test (T-shaped peeling) by punching my own tanzak-shaped specimen
Fully implemented. The measured value is shown as the average value of three samples.

Example-1 A, polymer production in an autoclave reactor with a capacity of 20 tons, xane feed rate 84/hour, residence time 45 minutes, gas phase ethyl/propylene molar ratio 0.9, gas phase Hydrogen was supplied at a concentration of 13 molar gas, and the vanadium catalyst component was prepared by adding 1.5 times the molar ratio of 2-butanol to oquin trichloride hivanadium (VOCl2) outside the reactor and dehydrochlorinating it with nitrogen gas. A vanadium compound concentration of 0.40 mmol/l-hexane was added.

4.0 mmol/l-hexane of ethylaluminum sesquichloride K was added as an organoaluminium arsenic, and the polymerization temperature was 37°C and the polymerization pressure was 6 ky.A small amount of water was added as a reaction terminator to the polymerization solution extracted from the polymerization solution. was expelled from the system by steam distillation and dried at 60°C.

The Mooney viscosity of the obtained polymer is ML, □(,...)
So 32, propylene content weight #25% A value 30 coefficient Mw/M
The molecular weight distribution was bimodal at n=12.0. The obtained polymer was sheeted, formed into square pellets using a sorting pelletizer, and used in the next reaction.

B. Polar group introduction For 100 parts of the polymer obtained in A, 1 part of maleic anhydride (special grade reagent crushed with a pestle), 0.3 part of organic peroxide (Kayahexa AD, manufactured by Kayaku Nouri)
part, anti-aging agent (Andata BHT: manufactured by Kawaguchi Chemical) 2
Mix the two parts well in advance, set the temperature to 200°C, and use a 55 mm diameter single-screw extruder with a screw rotation speed of 3 orpm.
(average residence time of 4 minutes).

Maleic anhydride content in the obtained reaction product (230°C
21.60 f load) was 2.35'/10 min.

The reaction product obtained in C0 property evaluation B was kneaded using a BR type Banbury mixer according to the formulation shown in Table 1 to obtain a compound.

Table 1 <Blend recipe> Using this compound, the molding processability was completely evaluated by an extrusion test. The extrusion rate is 530 y/min. The Garbe die shape evaluation point is (1
The sample had a score of 16 (out of 6), and the die swell was 14, indicating excellent workability.

Next, dicumyl peroxide and ethylene dimethacrylate (dicumyl peroxide) were added using iterol.

The obtained compounded rubber was press-vulcanized at 160° C. for 30 minutes and the physical properties of the vulcanization were measured. The results are shown in Table 2. It shows excellent adhesion to fibers.

Table-2 Vulcanized physical properties> 300% tensile stress (kzf/era) 80 tensile strength (l) 121 elongation (modulus) 500 fiber adhesion strength (krf,/crn) 6.5
(Rubber Destruction) Comparative Example-1 The same property evaluation as in Example-1 C was carried out using the polymer produced in Example-1 A. The results of the extrusion test were that the extrusion rate was 520 f/min, the carpe die shape evaluation score was 16 points (out of 16 points), and the die swell was 15 points. The results of evaluation of vulcanized physical properties are shown in Table 3.

Table-3 <Vulcanized physical properties> 300% tensile stress (kgfA) 70 Tensile strength (kqf/crl) 125 Elongation
(Part) 550 Fiber adhesive strength (1<q f /cm ) 1.6
Although the normal physical properties are good, the adhesion to fibers is poor.

Comparative Example-2 In the manufacturing method of Example-1 A, the gas phase ethylene/glolobylene molar ratio (C2/C3) *1.1, the total gas phase hydrogen concentration was 5 molar, and vanadium oxytrichloride (VOC73) was 1.
．． 2 mmol/1-hexane, n-butanol 0C
Added 15 times to t3, added ethylaluminum sesquichloride to 48 mmol/l-hexane, and polymerized temperature to 48°C.
The entire continuous polymerization reaction was carried out under the conditions of a polymerization pressure of 6' Kq/c shoulder/G, and the polymer was dried in the same manner as in A of Example-1.

The Mooney viscosity of the obtained polymer was 4.4 (to
O, c was 65, propylene content was 41φ, A value was 0, Mion/Mn was 13.3, and the molecular weight distribution was one peak. The obtained polymer was taken out of the tube, formed into square pellets using a sheet pelletizer, and used in the next reaction.

B. Polar group introduction The polymer obtained in A was reacted with maleic anhydride in the same manner as in B of Example-1. The maleic anhydride content in the resulting product was 1o, 5ts, and the melt 70-index (230°C, 21605' load) was 1.26.
(y/lo minutes).

C1 physical property evaluation Physical properties were evaluated in the same manner as in Example-1 C.

The results of the extrusion test were that the extrusion rate was 4609/min, the Garbe die shape evaluation score was 12 points (out of 16 points), and the die swell was 75 points. The physical properties of the additive are shown in Table 4. Adhesion to fibers is good, but extrusion processability is poor.

:) Table-4 Vulcanized physical properties> 300% tensile stress (kgf/CJ) 130 Tensile strength (') 166 Elongation (modulus) 330 Fiber adhesion strength (kgf,/Crn) 5.
6 (Rubber destruction) Example-2 A. In polymer production Example-1, gas phase ethylene/propylene (molar ratio) *0.7, gas phase hydrogen concentration 15 molar ratio, 2-
Butanol/VOC73 (mole ratio) total 1.0, vanadium compound concentration 0.60 mmol/l-hexane, ethyl aluminum sesquichloride 4.8 mmol/l-
Example except that hexane and polymerization temperature were changed to 30°C.
The polymerization reaction was carried out in the same manner as IA.

The Mooney viscosity of the obtained polymer was ML++4 (+00
'C) 50, propylene content 27 ZA value 25% Mw
7M n = 9.2, and the molecular weight distribution was 7 < immodal. The resulting polymer was taken out and made into square pellets using a sorting pelletizer, which was used in the next reaction.

B. Polar group introduction For 100 parts of the polymer obtained in A, 3 parts of styrene-maleic anhydride resin (Alastor 700: Arayo Kagaku, maleic anhydride content 43%), an organic radical generator (Verhequinone-25B2) 23 using 0.2 parts of Nippon Oil & Fats Co., Ltd.) and 2 parts of an anti-aging agent (Antage BHT: Kawaguchi Chemical Co., Ltd.)
The reaction was carried out in the same manner as in Example 1B except that the extruder temperature was set at 0°C.

The styrene-maleic anhydride resin content in the obtained reaction product was 27, and the melt flow index (23
At 0°C, 216 (l load) was 3.10 r/10 min.

C1 Physical property evaluation Using the reaction product obtained in B, an extrusion test and a physical property test were conducted in the same manner as in Example-IC.

The extrusion amount is 460? /min, carve die evaluation score (out of 16 points) was 16 points, and die swell was 20, indicating excellent extrusion processability.

Vulcanized physical properties are shown in Table-5. This example also showed excellent adhesion to fibers.

Table-5 Vulcanized physical properties> 300 tensile stress (kf/crn) 79 tensile strength (l) 137 elongation (kr) 390 fiber adhesion strength (kgf//crn) 7.0
(Rubber destruction) Example 3 B, polar group introduction example - 100 parts of the polymer obtained in IA, a total of 5 parts of acrylic acid, an organic radical generator (Kayahexa AD, manufactured by Kayaku Nouri) i 0. One part was used to carry out the reaction in the same manner as in Example-IB.

The acrylic acid content in the obtained reaction product was 1.0, and the melt flow index (230°C, 2160? load)
Is it 1.0? / It was 10 minutes.

Using the reaction product obtained in C0 physical property evaluation B, an extrusion test and a physical property test were conducted in the same manner as in Example-IC.

The extrusion rate is 521 y/min, and the curved die shape evaluation score (out of 16) is 16 points, and the die swell is 15%, indicating excellent extrusion processing. The vulcanized physical properties are shown in Table 6. This example also showed excellent adhesion to fibers.

Table-6 <Vulcanized physical properties> 300 modulus tensile stress (kyf/CM) 75 tensile strength
(・ ) 130 Elongation (%) 490 Fiber adhesive strength (kqf//crn) 6.7
(Rubber destruction) [Effects of the invention] The composition of the present invention has excellent moldability in an uncured state, and has excellent adhesion to fibers when vulcanized, so it can be used in various fiber-reinforced composites. Useful for applications such as

Claims (3)

[Claims] (1) Ethylene-α with bimodal molecular weight distribution
- 0.05 to 5 parts by weight of an organic radical generator in the presence of 0.01 to 2 parts by weight based on 100 parts by weight of the olefin copolymer.
A method for producing a modified ethylene-α-olefin copolymer composition, which comprises reacting with 0 parts by weight of a compound having a polar group. (2) The compound having a polar group is a compound containing one or more groups selected from the group consisting of a carboxyl group, a carboxylic acid ester residue, a carboxylic anhydride residue, an amino group, a hydroxyl group, and an epoxy group. A method for producing a modified ethylene-α-olefin copolymer composition according to claim (1), characterized in that: (3) Ethylene-α with bimodal molecular weight distribution
- Modified ethylene-α-olefin copolymer according to claim (1), characterized in that the area on the low molecular weight side of the olefin copolymer is 10 to 50% of the area of the entire molecular weight distribution. Method for producing polymer composition