JPS6176538A - Rubber composition - Google Patents

Abstract

PURPOSE:To provide a composition composed of a solid rubber and a liquid diene polymer having halogen at the terminal, and giving a vulcanized rubber having excellent mechanical properties especially tensile strength and modulus and low dynamic heat-generation. CONSTITUTION:The objective composition is produced by compounding 100 pts.(wt.) of a solid rubber with 1-50pts., preferably 5-45pts. of a liquid diene polymer having halogen atom at the terminal. The halogen in the polymer is preferably chlorine, and the polymer is preferably the one having a halogen- content of 0.01-20wt%, a number-average molecular weight of 300-20,000 and a viscosity of 0.1-3,000 poise at 25 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to rubber compositions, and more particularly to rubber compositions that provide vulcanized rubber with improved mechanical properties.

Conventionally, rubber compositions made by blending a solid comb with a liquid diene polymer having a hydroxyl group at the end have been known, and are used for various purposes. However, this composition
Although this composition has excellent handling properties and other workability during compounding, the mechanical properties of the vulcanized rubber obtained from this composition, particularly its tensile strength and modulus, are still unsatisfactory. Furthermore, there was also the drawback that the resulting vulcanized rubber had a large dynamic calorific value.

Therefore, the inventors of the present invention aimed to develop a rubber composition that solved the above-mentioned drawbacks (as a result of intensive research, they discovered that the desired comb composition could be obtained by adding a specific substance to a solid comb, and based on this knowledge, As a result, the present invention was completed.

That is, the present invention is a rubber composition comprising a solid rubber and a liquid diene polymer having a halogen at its terminal.

In the present invention, the solid rubber is not particularly limited, and synthetic rubber, natural rubber, etc. are widely used.

Specifically, butadiene rubber (BR), isoprene rubber (IR), chloroprene rubber (CR), styrene-butadiene rubber (SBR), acrylonitriloop polydiene rubber (NBR), isobutylene-isoprene rubber (IIR), and mixtures thereof1 Of course there is.

Next, the liquid diene-based polymer having a halogen at the terminal is prepared by the following →Cl(z--CI(-CH-CHZ÷ and →C
It is a liquid diene polymer consisting of repeating units of H, -CH←, which has halokenes at both ends. Examples of the halogen include fluorine, chlorine, bromine, and iodine, with chlorine being particularly preferred. There are no particular restrictions on the physical properties of the liquid diene polymer having a halogen-terminated polymer, but the halogen content is usually 0.01 to 20% by weight,
Number average molecular weight: 300-20,000, viscosity: 0.1-300
A material with a temperature of about 0 voise/25'C is used.

It has a halogen at such an end. Although the fitted diene polymer can be produced by various methods, the following method is particularly suitable. That is, →CH, -CH=CH-CH
, + δ and →CH, -CH←CH==CH.

This method involves reacting a halogen compound with a liquid diene polymer consisting of repeating units having hydroxyl groups at both ends. The number average molecular weight of the raw material liquid diene polymer having hydroxyl groups is 300 to 20,000.

Further, the halogen compound may include a variety of commonly used halogen compounds. For example, hydrogen bromide (HBr),
Examples include hydrogen halides such as hydrogen chloride (HCl), hydrogen fluoride (HF), and hydrogen iodide (Hl); and phosphorus halides such as phosphorus trihalide and phosphorus pentahalide. Here, as the phosphorus trihalide, the specific Q is P
There are B r:l I P CI :l, and PBrs is an example of phosphorus pentahalide.

PCI, etc. As the phosphorus halide, a compound of phosphorus and bromine can also be used.

In addition, halogen compounds include chlorhensen,
Promhensen, chlortoluene.

halogenated compounds such as fromtoluene; halogenated compounds such as methyl chloride, methyl bromide, carbon tetrachloride, and carbon tetrabromide; thionyl chloride;

Examples include thionyl halides such as thionyl bromide; acid halides such as acetyl chloride and acetyl bromide. Among these, thionyl halides such as thionyl chloride and thionyl bromide are particularly preferably used.

The reaction between a liquid diene polymer having a hydroxyl group at the terminal end and a halogen compound is usually carried out at a temperature of -10 to 200'C,
Preferably at 0 to 100°C and 1 to 20 atm pressure, preferably 1 to 10 atm for 0.1 to 24 hours, preferably 1
It is carried out for ~12 hours. Also, this reaction proceeds even in the absence of solvent, but? It is preferable to use a container.

Examples of the solvent used in this case include Hensen, chloroborum, dimethylformamide, acetonitrile, etc., and two or more of the above solvents &f1 can also be used in combination. Other stabilizers such as p-quinone, hydroquinone, hydroquinone monomethyl ether, BHT, sonitrophenol 3, nitrosophenol, etc. may be added if necessary.

In this way, a liquid tsene-based polymer having halogens at both ends and ends is obtained.

The rubber composition of the present invention basically consists of the above-mentioned solid rubber and a liquid diene polymer having a halogen at the end.
Various additives can be added if necessary. A specific example of an additive is sulfur.

Crosslinking agents such as organic sulfur compounds, metal oxides, and polyamines; Vulcanizing agents; Vulcanization accelerators such as aldehyde-amines, dithiocarbamates, guanidines, and sulfides; Vulcanization accelerators such as metal oxides and fatty acids. agent; amines;
Anti-aging agents such as amine-aldehyde reactants, amine-ketone reactants, and phenols; Reinforcing agents such as carbon flanoke and white carbonate; filling of calcium carbonate, basic magnesium carbonate, diatomaceous earth, clay, etc.;
V-wearing agents such as hydrogenated Ronn, coumaron-indene 11 fat, and voliften; dimethyl phthalate (DMP)
, diethyl phthalate (DEP), and diethyl phthalate (DOP); and process oils such as paraffinic, naphthenic, and aromatic.

The composition of the present invention can be obtained by blending the above components. There is no particular restriction on the blending amount of the solid comb and the liquid diene polymer having a halogen at the end, but usually 1 to 50 parts by weight of the liquid diene polymer having a halogen at the end, per 100 parts by weight of the solid rubber. Preferably 5-45
Parts by weight. If the amount is less than 1 part by weight, kneading becomes difficult, and if it exceeds 50 parts by weight, the mechanical properties of the resulting vulcanized rubber will deteriorate, which is not preferred.

The composition of each ingredient is 25 to 5
The mixture may be kneaded at about 5°C for about 10 minutes to about 1 hour.

The vulcanized comb obtained by vulcanizing this comb composition has excellent mechanical properties, especially tensile strength and modulus, and has a low dynamic calorific value.

Therefore, the rubber composition of the present invention can be very suitably used in various comb products, such as tires.

Next, the present invention will be explained in detail with reference to examples.

Production example (manufacture of liquid diene polymer containing chlorine at the end) In a 1β volume Mitsuroh flask with a cooling tube, hydroxyl-terminated liquid polybutadiene (number average molecular weight 2800, hydroxyl group content 0)
．． 79meq/g, Idemitsu Petrochemical (4'1 2rp
oly bd R-45HTJ), 600 m/chloroform as a reaction solvent, and 4 g of pyridine as a reaction aid were added, and the mixture was cooled to 5°C. Next, this melt? Add 5.7 g of thionyl chloride (manufactured by Wako Pure Chemical Industries, special grade) diluted with 10 ml of chloroform to 30
It was dripped over several minutes. Thereafter, the reaction was carried out for 2 hours while maintaining the temperature at 5"C, and the reaction was further carried out for 6 hours under refluxing chloroform. After the reaction was completed, 100 ml of F distilled water was added and stirred to remove unreacted thionyl chloride. Next, this reaction solution was transferred to a 21 separatory funnel, and about 6
Washing was performed twice by adding 00m AO dilute distilled water. After separation, the solvent was removed to obtain 40.3 g of a reaction product.

The molecular ar results of the physical properties of this reactant are shown below.

Hydroxyl group equivalent: 0.08 meq/g (by acetylation method) Chlorine content: 1.87% by weight Viscosity: 125 poise/15°C Elemental analysis: Carbon 87.0%, Hydrogen 10.9%.

Oxygen 0.3%, chlorine 1.87% Also, as a result of infrared absorption spectrum analysis (IR analysis), 3200
It was observed that absorption by hydroxyl groups at ~3600 cm-' disappeared.

Examples 1 to 2 and Comparative Examples 1 to 3 Predetermined amounts of each component shown in Table 1 were blended and kneaded using an internal mixer roll at 45°C for 30 minutes to obtain a rubber composition.

The apparent viscosity of this product is shown in Table 1.

The obtained comb composition was press-vulcanized at 150°C for 30 minutes to obtain a vulcanized rubber. The tensile strength and elongation of this item are 30
The 0% modulus and calorific value are shown in Table 1.

*1: Obtained in production example, average molecular weight A *2
...Number average molecular weight 2800. Hydroxyl group content: 0.79m
eq/g, Idemitsu Petrochemical (1 chrysanthemum, 1-poly
bd R-45t (TJ*3...Oil Furnace Furanoku 7.1...Measured with Koka type flow tester*
5...Based on JISK6301*6...ASTMD-623 Knodorinotiflexometer (note: 251b, stroke 4.44mu, 7g degree 100°02 rotation G1800rpm, measurement time 25 minutes)

Claims (1)

[Scope of Claims] 1) A rubber composition comprising a solid rubber and a liquid diene polymer having a halogen terminal. 2) The rubber composition according to claim 1, wherein 1 to 50 parts by weight of a liquid diene polymer having a terminal halogen is blended with 100 parts by weight of solid rubber. 3) The rubber composition according to claim 1, wherein the halogen is chlorine.