JPS58132033A - Thermoplastic elastomer composition - Google Patents

Abstract

PURPOSE:The titled composition excellent in heat resistance, oil resistance, abrasion resistance, etc., and suitable for use in soles, industrial rubber products, etc., consisting mainly of a thermoplastic block elastomer and a specified graft copolymer. CONSTITUTION:To 100pts.wt. mixture containing 80-20pts.wt. thermoplastic block elastomer consisting of 75-50wt% conjugated diene and 25-50wt% aromatic vinyl compound and 20-80pts.wt. graft copolymer prepared by copolymerizing 30-70wt% diene rubber polymer with 70-30wt% mixture (weight ratio f 40:60-10:90) of an acrylic monomer and an aromatic vinyl monomer are added 10-80pts.wt. naphthenic process oil consisting of 3-10wt% aromatics, 20- 42wt% naphthenes and 32-52wt% aliphatics, 10-60pts.wt. inorganic filler (e.g., silica) and 50-2,000 ppm of an organic peroxide (e.g., benzoyl peroxide).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a thermoplastic Zoroku elastomer, a diene rubber-like polymer, an aromatic vinyl compound, and an acrylic monomer.
A thermoplastic elastomer composition having excellent heat resistance, oil resistance, and abrasion resistance properties, the main component being a mixture of a graft mixture and a graft mixture.

BACKGROUND ART Conventionally, thermoplastic block elastic bodies (hereinafter referred to as block elastic bodies) made of a conjugated diene and an aromatic vinyl compound exhibit good im-elasticity at room temperature, and melt and flow at high temperatures. This block elastic body generally has the property Y that it can be molded in the same manner as thermoplastic resin, and is used for shoe soles and industrial products.

However, such block elastic bodies are significantly inferior in heat resistance, oil resistance, and abrasion resistance compared to vulcanized imes;
lK, oil resistance, for example, kerosene Ig! 9. Completely and completely understand. Therefore, it is oil resistant! Although it has the advantage of being a molder in the desired field, it has the disadvantage that its application is limited to extreme pressure.

Various attempts have been proposed to improve these drawbacks. That is, (1) the block elastic body is crosslinked using peroxide or the like. (2) Mixing thermoplastic resin such as olefin. Methods such as these have been made, but in practical terms physical properties such as heat resistance, oil resistance, and abrasion resistance! No well-balanced improvements have been found.

In order to solve the above-mentioned drawbacks, the present invention has been made through extensive research and has resulted in the completion of a composition that has excellent heat resistance, oil resistance, abrasion resistance, etc., and is suitable for bim shoes and industrial products II+. .

That is, the present invention provides a thermoplastic block elastomer made of a conjugated diene and an aromatic vinyl compound, a diene-based rubbery polymer, an aromatic vinyl compound, an acrylic monomer, and an acrylic monomer.
The main component is a graft copolymerization stopper mixture obtained by copolymerization, and 1-naphthenic descess oil, an inorganic filler, and a peroxide are also added to make the scales %.

The present invention will be explained in detail below! 12 dawn.

The block elastic body of a conjugated diene and an aromatic vinyl compound used in the present invention is A(-B-A)n-1, (A-B
)n, (mu-B)nx. (In the formula, A represents an aromatic vinyl compound, B represents a conjugated vinyl compound, X represents a polyfunctional compound in which n polymer chains are bonded, and n represents 2 to ) The conjugated dienes in the block elastomer are 1,6-butadiene, 1', 3-pentadiene, 1,3-hexadiene, and isoprene, and the aromatic vinyl compounds are styrene,
α-methylstyrene, vinyltoluene, and t-butylstyrene e.

The block elastic body in the thermoplastic elastic body composition of the present invention is
In particular, it is preferable that the aromatic vinyl' compound be contained in the block elastomer in an amount of 25 to 50% by weight. If the weight of the aromatic vinyl compound is less than 25%, the demic chains of the aromatic vinyl compound, which serve as pseudo-crosslinking points, will be small and the tensile strength will decrease, making it unusable. Also, 5
If it exceeds 0% by weight, imelasticity will be significantly reduced, which is not preferable.

The graft comonomer used in the present invention is composed of a diene-based polymer, an aromatic vinyl compound, and an acrylic monomer, and examples of the diene-based polymer include butadiene,
Homopolymers of conjugated diene monomers such as isoprene, zomethylptazoene, cyclopentadiene, lyaaf, and cyanoprene, or monomers copolymerizable with these diene monomers, such as styrene, acrylonitrile, and methyl. Copolymers with methacrylate, ethyl acrylate, inbutylene, and 1-butene monomers are produced.

Next, the aromatic vinyl compounds to be graft copolymerized include styrene, α-methylstyrene, vinyltoluene,
These are chlorstyrene and t-butylstyrene. Examples of the acrylic monomer to be similarly graft copolymerized include acrylonitrile, methacrylatetril, methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, and the like.

The proportion of diene rubber 1 in the graft copolymer is 60 to 70% by weight, and the proportion of acrylic monomer and aromatic 1? The total amount with the nil compound monomer is 70 to 30% by weight. Further, the monomer ratio of the acrylic monomer to the aromatic vinyl compound is from 40:60 to 10:90. If the ratio of Al combination in the diene system is less than 30% by weight, the elastic properties will deteriorate, which is undesirable, and if it exceeds 70 qbv by weight, the fluidity will decrease and the moldability will become poor. Furthermore, if the weight ratio of the acrylic monomer to 2 m of monomers exceeds 40% by weight, the graft material will turn brown, which is undesirable, and if it is less than 10% by weight, the oil resistance will be insufficient. becomes.

The composition ratio of the block elastic body and the graft copolymer is 80
: 20-20 : 80, preferably 75825
~25nia 5 parts by weight. If there is a large amount of demiphta copolymer outside this f# range, improvements in oil resistance, heat resistance, and abrasion resistance will be insufficient, and if there is a large amount of graft copolymer,
It is not preferable because it has poor moldability and poor elasticity.

Although the present invention is mainly composed of a mixture of a block elastic body and a grafted body, the effect can be improved depending on the use by using the following sardine additive.

In other words, as a naphthenic process oil, general K
WJ commercially available, preferably composition 42% by weight
and 32 to 65% by weight aliphatic. The amount added is 1 for 10011 parts of (al and ('bl).
The amount is 0 to 80 parts by weight, preferably 20 to 60 parts by weight. If the amount added is less than 10 parts by weight, fluidity will be insufficient, and 801
If it exceeds 1 part, the improvement in 11 oil properties will be insufficient. This naphthenic process oil leads to uniform hardness of the composition, improved fluidity, and cost reduction.For example, the hardness of general shoe soles is required to be 50 to 80 based on Shore acid YH, and the hardness is within the above range. Request @ due to limited addition amount! a'V can be achieved.

Inorganic fillers used in the present invention include light or heavy calcium carbonate, magnesium carbonate, barium carbonate, silica, aluminum hydroxide, kaolin clay, and carbon black.

The amount added is 10 to 601 M parts, preferably 10 to 50 M parts, per 100 parts of (a) and (bl ff).
It is a quantity part. If the amount added is less than 103,111 parts, it will substantially help improve oil absorption and rigidity, but if it exceeds 6ON-1 parts, the impact resilience, which is an im-like property, will decrease, which is undesirable.

Furthermore, in the present invention, performance can be further improved by crosslinking with the Ij4Ili product V peroxide. In other words, the addition of peroxide promotes co-crosslinking of both the block elastic body and graft components, and increases the molecular weight of MtK to an extent that does not impair injection moldability, resulting in better oil resistance! It is estimated that this will lead to further improvement.

Examples of monopoles of peroxides include benzoyl peroxide, socumyl peroxide v1 sitagelizotyl peroxide, t-butyl peroxypene Kameido ate, and t-butyl peroxypene Kameido ate.
-butylperoxyacetate, t-butylperoxyoctoate, and particularly preferred is benzoyl peroxide. The amount added is 50 to 2000 P per 100 parts by weight of components (IL) and (b).
PM, preferably 2oo to 2000 PPM. 5
If it is less than 3 PPM, the thermal resistance is small and the performance is not comparable, and if it exceeds 2000 PPM, crosslinking becomes excessive, fluidity decreases, and processability deteriorates. This peroxide is preferably added at the fi1 stage and heated and crosslinked.

Furthermore, 1. the composition may optionally contain an anti-aging agent,
In addition to the ultraviolet absorber and antistatic agent, fuels, reinforcing agents, blowing agents, coloring agents, lubricants, fragrances and other fillers may also be added.

The molding method of the present invention can be any molding method such as extrusion molding, injection molding, compression molding, hollow blow molding, etc. depending on the purpose.

Applications include various shoe soles and industrial rubber products.

The present invention will be explained in detail below with reference to Examples.

Examples 1 to 3 A block elastomer of the components (Ma, η) and a graft copolymer of the (Bl) component were obtained by the following manufacturing method.

50 g of dehydrated and purified cyclohexane and 1,51 trV of styrene mono-?
After adding n-butyl lithium v150a + mox at 40°C and polymerizing, add 7% of putadiene V and reacting at 60°C.
Polymerize for 1 hour. Subsequently, styrene monomer Y 1
．． 51! r, and polymerization was carried out at 40°C for 1 hour. After that, 10F methanol was added to polymerize vP and bind, and then 0.5 PHRf each of 4-methyA, -2,6-ditardialisotylphenol and trinonyl phosphite were added as antiaging agents. Polymer 1 was precipitated by a steam stripping method. The melt flow index of the obtained block elastic body (200°C, 5Ili
PIFJ weight) was 9.6F/10 minutes.

(Bll external manufacturing method Polybutadiene latex (solid content 3) in an autoclave
Next, 186 parts of pure water, 3 parts of sodium dodecylbenzenesulfonate, 0.002 parts of ferrous imageate, and 0.0 parts of tetrasodium ethylenezoannetetraacetate were added. 0.004 parts, sodium aldehyde sulfoxylate) 0.12ff31, 4.8 parts of acrylonitrile, 11.2 parts of styrene, 0.096 parts of t-dodecylmercaptan, and 0.06 parts of benzoyl peroxide, and stirred under a nitrogen atmosphere. ,Ta. The contents were heated to 50°C and held for 2 hours. Next, Acrylic o=Trill 19.
A monomer mixture consisting of 2 parts of styrene, 44.8 parts of styrene, 0.384 parts of t-dodecylmercaptan, and 0.12 parts of benzoyl peroxide was continuously added over 8 hours. After the addition was completed, the mixture was further stirred at 70° C. for 2 hours to complete 1 cup, thereby obtaining latex V of the graft material. A calcium chloride aqueous solution V# was added to this, and a powdery polymer I was obtained by a salting out method.

Evaluation of ship product The (M) and (Bl) components were blended in the composition ratio shown in Table 1 in a Henschel mixer and extruded into pellets using a 40X extruder. A test piece was made from the mold and various physical properties were measured, and the results are shown in Table 1.

Comparative Example IK Comparing Examples 1 to 3, 1. The lI@ rate due to immersion in Tl8-1 oil and kerosene is small, that is, the oil resistance is greatly improved, and the dependence of hardness on stroke is small, that is, the heat resistance is good, and the wear resistance is It can be said that Pico wear 1, which is a measure, also has a small characteristic.

Comparative Example 1 The physical property values of only the component (A) of the block elastic body are shown in Table 1.

Comparative Example 2 Molding using only the component @) of the graft copolymer was impossible due to poor fluidity.

Examples 4 to 6 Examples 1 to 6 were used as the block elastic bodies except that in the method for producing the block elastic bodies used in Examples 1 to 6, the amount of n-butyllithium 'k 100 mmoli of the initiator was used.
Polymer I obtained in the same manner as in the production method of No. 6 was used. The melt flow index of this polymer (200℃, 5
4 cargo M) is 0.011710 minutes. Further, as the graft copolymer, the polymer t described in Examples 1 to 3 was used as it was. In addition, block copolymers, graft copolymers, naphthenic process oils (manufactured by Idemitsu Kosan,
xi calcium carbonate (manufactured by Shiraishi Calcium ■, product name Whiten 5) and as an inorganic filler
B) v Mixed with the predetermined composition shown in Table 2, Examples 1 to 3
Same physical properties as ilj feet! went. The results are shown in Table 2.

Comparative Example 3 In Example 4, physical property values when only the demik elastic body was used as the f reamer component are shown in Table 2.

Comparative Example 4 In Example 4, the physical properties gMv when only the graft copolymer was used as the polymer component are shown in Table 2.

Although the oil resistance is relatively good, the fluidity is low, so the hot water release property is poor, and the immability property 51 is poor.

Examples 7 to 9 In each set of Examples 4 to 6, a predetermined amount of benzoyl peroxide was further added, and then extruded into 9 pellets) 4
The physical properties were evaluated in the same manner as in Examples 1 to 3, and the results are shown in Table 3.

Comparative Example 5 In Example 8#/c, the physical properties were obtained when only the polymer-capable copolymer was used (shown in Table 6 of IILV).

The above physical properties method was based on the following criteria.

1, 7 hardness: :rxs-x-6301 (see 7 hardness 11'A) 2, melt flow index: A
8TM-D-1328, measured at 200°C and 5 load conditions 3. Oil resistance: J-K5-x-6501 J-KE+-1 After immersion in oil and kerosene for 20 hours at 20°C, The rate of increase in weight was determined.

4. f: Yll wear: Pico wear amount was determined based on A8TM-D-2228km.

5. Resilience modulus: Based on BS Standards Team 903tlt, measurement temperature 20℃ Patent applicant: Denki Kagaku Kogyo Co., Ltd. March 1980 Japan Patent Office Commissioner Shima 1) Haruki Tono 1, Indication of incident Patent application No. 1988 14647 No. 2, Name of the invention: Thermoplastic elastomer composition 3, Relationship with the amended party's case Patent applicant's address: 1-4-1 Yurakucho, Chiyoda-ku, Tokyo Next to the detailed description of the invention in the specification Add 11 or 2 or more species to

2. Add one or more of 1 or more of 1 next to [Crylate, etc.] on page 6, line 15 of the specification.

Claims (3)

[Claims] (1) (&) 80 to 20 parts by weight of thermoplastic block elastomer consisting of a conjugated diene and an aromatic vinyl compound (b) A diene plume-like polymer, an aromatic vinyl compound, and an acrylic monomer! Raft copolymer obtained by copolymerization 20~
80 parts by weight of a thermoplastic elastomer composition. (2) (a) 80 to 20 parts by weight of a plastic demik elastomer consisting of a conjugated diene and an aromatic vinyl compound (bl: Y copolymerized with a diene demik polymer, an aromatic vinyl compound, an acrylic monomer, Graft copolymer 20~
80 parts by weight (C) 10 to 801 parts of nandene-based zoro-nansu oil (a) A thermoplastic elastomer composition comprising as a main component a mixture with 10 to 60 parts by weight of an inorganic filler. (3) (al) 80 to 20 parts by weight of a thermoplastic demik elastomer made of a conjugated diene and an aromatic vinyl compound (b) t-copolymerized with a diene plume-like polymer, an aromatic vinyl compound, and an acrylic monomer Graft copolymer 20~
8ONi # part (cl naphthene thread process oil 10
~8ON Kurabe (al Inorganic filler 10-60 parts by weight (e) (a
A thermoplastic elastomer composition comprising as a main component a mixture of 50 to 2000 PPM of an organic peroxide based on 100 parts by weight of 1 and (b) ili'.