JPH0834816A - Hydrogenated diene copolymer and composition thereof - Google Patents

Abstract

PURPOSE:To obtain a hydrogenated diene copolymer excellent in vibration- damping properties and low-temperature flexibility by hydrogenating a diene copolymer composed of blocks of block copolymers having specified structures. CONSTITUTION:This copolymer is obtained by hydrogenating a diene copolymer composed of at least one block (A) of a polybutadiene having a number-average molecular weight of 2500-100000 and a 1, 2 bond content of 30mol% or below, at least one block (B) of a polyisoprene or isoprene/butadiene copolymer having a number-average molecular weight of 10000-200000 and a vinyl bond content of 30mol% or below and at least one block (C) of a polyisoprene, polybutadiene or isoprene/butadiene copolymer having a number-average molecular weight of 10000-200000 and a vinyl bond content of 40mol % or above and has a number-average molecular weight of 22500-500000. The contents of blocks A, B and C are 5-90wt.% respectively.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention provides a hydrogenated diene-based copolymer having excellent vibration damping performance and flexibility at low temperature, and impact resistance and vibration damping performance by the hydrogenated diene copolymer. It relates to the applied composition.

[0002]

2. Description of the Related Art A styrene-isoprene block copolymer is known as a thermoplastic elastomer having vibration damping performance (JP-A-2-102212). It is also known that a molding material having excellent vibration damping performance can be obtained by compounding this thermoplastic elastomer and plastics (JP-A-2-300250 and JP-A-3-).
43244 publication). However, since this thermoplastic elastomer has a glass transition temperature around room temperature, it has a problem that when it is blended with plastics, the impact resistance is low at low temperature.

[0003]

An object of the present invention is to provide a material having a good balance between vibration damping performance and low temperature impact resistance.

[0004]

The present inventors have arrived at the present invention as a result of extensive studies on the above points.
That is, the present invention has a number average molecular weight of 2500 to 1000.
And a block (A) made of polybutadiene having a 1,2 bond content of 30 mol% or less and a number average molecular weight of 1
20,000 to 200,000 and a vinyl bond amount of 3
Block (B) consisting of 0 mol% or less of polyisoprene or isoprene-butadiene copolymer and polyisoprene, polybutadiene or isoprene-butadiene copolymer having a number average molecular weight of 10,000 to 200,000 and a vinyl bond content of 40 mol% or more. The present invention relates to a hydrogenated diene-based copolymer obtained by hydrogenating a diene-based copolymer having a number average molecular weight of 22,500 to 500,000 containing at least one block (C) made of a polymer, and a composition thereof.

The present invention will be described in more detail below.

The block (A) constituting the hydrogenated diene copolymer of the present invention has a number average molecular weight of 2500 to 1000.
It is necessary that the content of the polybutadiene is 00 and the amount of 1,2 bonds is 30 mol% or less.

When the molecular weight is less than 2,500, the mechanical strength of the hydrogenated diene copolymer itself is lowered, which is 1
When it exceeds 00000, the hydrogenated solution after the hydrogenation reaction becomes wax and the handling becomes difficult, which is not preferable.

If the amount of 1,2 bonds exceeds 30 mol%, the crystallinity of the block (A) is lowered and the mechanical strength of the hydrogenated diene copolymer itself is lowered, which is not preferable.

Block (A) in hydrogenated diene copolymer
The ratio is preferably 5 to 90% by weight. If it is less than 5% by weight, the mechanical strength of the hydrogenated diene-based copolymer itself is lowered, and conversely if it exceeds 90% by weight, sufficient vibration damping performance cannot be obtained, which is not preferable.

The block (B) constituting the hydrogenated diene copolymer of the present invention has a number average molecular weight of 10,000 to 200.
It is necessary to be composed of polyisoprene or isoprene-butadiene copolymer having a vinyl bond content of 30 mol% or less.

When the molecular weight of the block (B) is less than 10,000, the mechanical strength of the hydrogenated diene copolymer itself is lowered, and conversely, when it exceeds 200,000, the melt viscosity is increased and the processability is deteriorated, which is preferable. Absent.

Further, when the vinyl bond amount is more than 30 mol%, the flexibility of the hydrogenated diene copolymer at low temperature cannot be obtained, and when the composition is used, the impact resistance at low temperature cannot be obtained. Not preferable.

The block (B) is polyisoprene or an isoprene-butadiene copolymer, but polyisoprene is preferably used when flexibility at low temperature is important, and mechanical strength is important. It is preferable to use an isoprene-butadiene copolymer.

When the isoprene-butadiene copolymer is used, the butadiene content is preferably 80% by weight or less. This is because if butadiene exceeds 80% by weight, crystallinity becomes high and rubber elasticity is lost. In this case, the form of isoprene and butadiene is preferably random or tapered.

Block (B) in hydrogenated diene copolymer
The ratio is preferably 5 to 90% by weight. If it is less than 5% by weight, the flexibility of the hydrogenated diene-based copolymer at low temperature or the impact resistance at low temperature cannot be obtained when it is made into a composition, and conversely if it exceeds 90% by weight. It is not preferable because sufficient vibration damping performance and flexibility at low temperature cannot be obtained.

The block (C) constituting the hydrogenated diene copolymer of the present invention has a number average molecular weight of 10,000 to 20.
Polyisoprene, polybutadiene or isoprene having a vinyl bond content of 40 mol% or more
It must consist of a butadiene copolymer.

When the molecular weight of the block (C) is less than 10,000, the mechanical strength of the hydrogenated diene-based copolymer itself decreases, and conversely, when it exceeds 200,000, the melt viscosity becomes high and the processability deteriorates. Not preferable. If the vinyl bond content is less than 40 mol%, the vibration damping performance at around room temperature cannot be obtained, which is not preferable.

The block (C) is polyisoprene, polybutadiene or isoprene-butadiene copolymer, but when importance is attached to the vibration damping performance at room temperature, it is preferable to use polyisoprene or isoprene-butadiene copolymer, More preferred is polyisoprene.

When an isoprene-butadiene copolymer is used, the ratio of isoprene and butadiene is not particularly limited. The form of isoprene and butadiene in this case may be block, random or tapered.

Block (C) in hydrogenated diene copolymer
The ratio is preferably 5 to 90% by weight. If it is less than 5% by weight, sufficient vibration damping performance cannot be obtained, and conversely, if it exceeds 90% by weight, the flexibility of the hydrogenated diene-based copolymer at low temperature is impaired, and a composition is obtained. In particular, the impact resistance at low temperature cannot be obtained, which is not preferable.

The form of the hydrogenated diene copolymer may be linear or branched. Further, there is no particular limitation on the combining order of the blocks, and at least one of the blocks is
One is enough.

The hydrogenation rate of the hydrogenated diene copolymer of the present invention is preferably 70% or more. If it is lower than 70%, the block (A) does not show crystallinity, and therefore the hydrogenated diene-based copolymer itself cannot obtain sufficient mechanical strength, which is not preferable. From the viewpoint of heat resistance and weather resistance, the hydrogenation rate is preferably 70% or more, more preferably 80% or more.

The hydrogenated diene-based copolymer of the present invention is obtained by the following method.

First, the block copolymer before hydrogenation is
It is produced by a method of sequentially adding a monomer with an alkyllithium compound as an initiator and polymerizing it, or a method of sequentially adding a monomer with an alkyllithium compound as an initiator and polymerizing and then coupling with a coupling agent.

Examples of the alkyl lithium compound include alkyl compounds having an alkyl residue having 1 to 10 carbon atoms, and methyl lithium, ethyl lithium, pentyl lithium and butyl lithium are particularly preferable. Dichloromethane, dibromomethane, dichloroethane, dibromoethane, dibromobenzene and the like are used as the coupling agent. Examples of the dilithium compound include naphthalenedilithium and dithiohexylbenzene. The amount of the initiator used is determined by the required molecular weight, but is generally 0.0
It is used in the range of 1 to 0.2 parts by weight.

The amount of vinyl bonds in the isoprene, butadiene or isoprene-butadiene of the block (C) is 4
In order to have 0 mol% or more, a Lewis base is used as a cocatalyst during the polymerization of isoprene. Examples of Lewis bases include ethers such as dimethyl ether, diethyl ether and tetrahydrofuran, glycol ethers such as ethylene glycol dimethyl ether and diethylene glycol dimethyl ether, triethylamine, N, N, N ′, N′-tetramethylethylenediamine (TME
DA), amine compounds such as N-methylmorpholine, and the like. The amount of these Lewis bases used is generally in the range of 0.1 to 1000 times the number of moles of lithium as the polymerization initiator.

It is preferable to use a solvent for easy control during the polymerization. As the solvent, an organic solvent which is inert to the polymerization initiator is used. Especially carbon number is 6 ~ 1
The aliphatic, alicyclic and aromatic hydrocarbons of 2 are preferably used. Examples thereof include hexane, heptane, cyclohexane, methylcyclohexane, benzene and the like.

The polymerization can be carried out in the range of 0 to 0 by any polymerization method.
It is carried out at a temperature range of 80 ° C. for 0.5 to 50 hours.

Next, hydrogenation of the diene copolymer is carried out by a known method. For the hydrogenation reaction, a method of reacting hydrogen in a molecular state with a known hydrogenation catalyst in a state of being dissolved in a hydrogenation catalyst and a solvent inert to the reaction is preferably used. As the catalyst used, Raney nickel or a metal such as Pt, Pd, Ru, Rh or Ni is carbon,
Alumina, heterogeneous catalysts such as those supported on a carrier such as diatomaceous earth, or transition metals and alkyl aluminum compounds,
A Ziegler type catalyst or the like composed of a combination of alkyl lithium compounds and the like is used. The reaction is carried out at a hydrogen pressure of normal pressure to 200 kg / cm ² , a reaction temperature of normal temperature to 250 ° C., and a reaction time of 0.1 to 100 hours. After the reaction, the block copolymer is obtained by coagulating the reaction solution with methanol or the like and then heating or drying under reduced pressure, or by pouring the reaction solution into boiling water to azeotropically remove the solvent and then heating or drying under reduced pressure. can get.

The hydrogenated diene-based copolymer of the present invention is used alone as a molding material, but it can be blended with other polymers to be used as a composition, thereby exhibiting excellent effects. There is. Examples of the polymer include NR, IR, BR, SBR, EPR, EPD.
M, butyl rubber, boribten, low molecular weight polyisoprene, low molecular weight polybutadiene, low molecular weight isoprene-butadiene copolymer and hydrogenated products thereof, styrene-butadiene block copolymer and styrene-isoprene block copolymer, and hydrogenated products thereof Ethylene copolymer such as ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, thermoplastic polyurethane, thermoplastic polyester, thermoplastic polyamide, polyethylene, polypropylene, etc. Polyolefin, polystyrene, AB
Examples thereof include styrene resins such as S resins and AES resins, polyamide resins, and polyester resins. Further, the above polymer may be one having a functional group added in the molecular chain or at the molecular end.

The blending ratio of these polymers varies depending on the purpose, but is preferably 95% by weight or less with respect to the hydrogenated diene copolymer of the present invention.

Further, the composition of the present invention may contain various additives as long as the properties thereof are not impaired. Examples thereof include 5 to 250 parts by weight of a plasticizer / softening agent such as oil based on 100 parts by weight of the polymer component, 5
To 300 parts by weight of carbon black, silica, calcium carbonate, talc, mica, glass fiber and other reinforcing agents or fillers, and 0.01 to 5 parts by weight of antioxidants, ultraviolet absorbers, colorants and the like. To be In particular, mica is preferably used because it improves vibration damping performance.

The hydrogenated diene copolymer and composition of the present invention are mixed by a kneader, a roll or an extruder, and can be easily formed into a molded product by a general molding method such as press molding, injection molding or extrusion molding. it can.

The composition of the present invention is optionally crosslinked before use. As the cross-linking agent, sulfur, peroxide, etc. are used. Crosslinking can be easily carried out using the general methods and equipment used for the crosslinking of conventional rubber.

The hydrogenated diene-based copolymer and composition of the present invention are used as molding materials for automobile interior materials, exterior materials, sheets, and
Used for films, hoses, tubes, medical materials, sports equipment, toys, household goods, textiles, etc. Further, it can be applied to a cloth or can be used as a laminate with a thermoplastic resin, a thermosetting resin, a steel plate, a plywood, an elastomer or the like.

[0036]

EXAMPLES The present invention will be described in more detail below with reference to examples. Each measured value in Examples and Comparative Examples was determined by the following method. ◎ Molecular weight depends on GPC. ◎ For the microstructure, the NMR spectrum was calculated. ◎ The hydrogenation rate was calculated from the ratio of the iodine values of the diene-based copolymer before and after the hydrogenation reaction. ◎ Damping performance is 0,2 determined by dynamic viscoelasticity measurement
The tan δ value at 0 and 40 ° C was used for evaluation. ◎ Impact strength was measured by an Izod tester (JIS K7110).

Example 1 Polymerization was carried out in the order of isoprene, butadiene and isoprene by using cyclohexane as a solvent, n-butyllithium as a polymerization catalyst and THF as a vinylating agent in a dry nitrogen-substituted 5 liter pressure resistant reactor. An ABC type diene-based copolymer (I) was obtained. The resulting copolymer (I) is
Using Pd-C as a hydrogenation catalyst in cyclohexane,
Hydrogenation reaction was carried out at a hydrogen pressure of 20 kg / cm ² to obtain a hydrogenated diene-based copolymer (I). The molecular characteristics are shown in Table 1. A composition was prepared by kneading the obtained hydrogenated diene-based copolymer (I) at 200 ° C. with a Brabender plastic coater according to the formulation shown in Table 3, and for a sample press-molded at 210 ° C.-20, The Izod impact strength at 25 ° C. and the tan δ at 0, 20, and 40 ° C. were measured. The measurement results are shown in Table 3.

Example 2 Isoprene-butadiene (isoprene / butadiene = 5)
0/50), butadiene, and isoprene were polymerized in this order to carry out polymerization and hydrogenation reaction in the same manner as in Example 1 to obtain a hydrogenated diene copolymer (II). The molecular characteristics are shown in Table 1. The hydrogenated diene-based copolymer (II) thus obtained was kneaded, molded and measured in the same manner as in Example 1. The measurement results are shown in Table 3.

Example 3 Polymerization and hydrogenation reaction were carried out in the same manner as in Example 1 except that isoprene, butadiene and isoprene-butadiene (isoprene / butadiene = 50/50) were polymerized in this order, and a hydrogenated diene copolymer was obtained. (III) was obtained. The molecular characteristics are shown in Table 1. The obtained hydrogenated diene copolymer (III) was kneaded, molded and measured in the same manner as in Example 1. The measurement results are shown in Table 3.

Comparative Example 1 Polymerization and hydrogenation reaction were carried out in the same manner as in Example 1 except that isoprene and butadiene were polymerized in this order and THF was not used to obtain a hydrogenated diene copolymer (IV). The molecular characteristics are shown in Table 1. The obtained hydrogenated diene copolymer (IV) was kneaded, molded and measured in the same manner as in Example 1. The measurement results are shown in Table 3.

[0041]

[Table 1]

Comparative Example 2 Example 1 except that butadiene and isoprene were polymerized in this order.
Polymerization and hydrogenation reaction were carried out in the same manner as in 1. to obtain a hydrogenated diene-based copolymer (V). The hydrogenated diene-based copolymer (V) thus obtained was kneaded, molded and measured in the same manner as in Example 1. The measurement results are shown in Table 3.

Comparative Example 3 Styrene, isoprene and styrene were polymerized in this order, and THF was added.
Was used as a vinylating agent and polymerized and hydrogenated in the same manner as in Example 1 to obtain a styrene-based copolymer (I). The molecular characteristics are shown in Table 2. The obtained styrene copolymer (I) was kneaded, molded and measured in the same manner as in Example 1. The measurement results are shown in Table 3.

[0044]

[Table 2]

[0045]

[Table 3]

From the results shown in Table 3, it can be seen that the composition containing the hydrogenated diene copolymer of the present invention is a material excellent in vibration damping performance and low temperature impact strength.

[0047]

The composition containing the hydrogenated diene-based copolymer of the present invention is a material having an excellent balance between vibration damping performance and low temperature impact resistance, and is required to have vibration damping performance and impact resistance. It can be used for various purposes.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiromichi Nakata 36 Towada, Kamisu-cho, Kashima-gun, Ibaraki Prefecture Kuraray Co., Ltd.

Claims (5)

[Claims] 1. A number average molecular weight of 2,500 to 100,000.
And a block (A) made of polybutadiene having a 1,2 bond content of 30 mol% or less and a number average molecular weight of 100.
Block (B) composed of polyisoprene or isoprene-butadiene copolymer having a vinyl bond content of 30 mol% or less and a number average molecular weight of 10,000 to 200,000 and a vinyl bond content of 40 mol%. Hydrogenated diene system obtained by hydrogenating a diene copolymer having a number average molecular weight of 22,500 to 500,000 containing at least one block (C) composed of the above polyisoprene, polybutadiene or isoprene-butadiene copolymer Copolymer. 2. The hydrogenation according to claim 1, wherein the block (B) is composed of polyisoprene having a vinyl bond content of 30 mol% or less and the block (C) is composed of an isoprene-butadiene copolymer having a vinyl bond content of 40 mol% or more. Diene copolymer. 3. The hydrogenated diene-based copolymer according to claim 1, wherein the proportion of block (A), block (B) or block (C) in the hydrogenated diene-based copolymer is 5 to 90%, respectively. Polymer. 4. The hydrogenation rate of the hydrogenated diene-based copolymer is 70%.
The hydrogenated diene-based copolymer according to claim 1, which is the above. 5. A composition comprising the hydrogenated diene-based copolymer according to claim 1 and another polymer.