JP2013203742A - p-tert-OCTYLPHENOL-SULFUR CHLORIDE CO-CONDENSED RESIN - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a p-tert-octylphenol-sulfur chloride co-condensed resin useful as a resin-crosslinking agent having characteristics of improving viscoelastic characteristics compared to the case using sulfur without damaging breaking characteristics when added to a rubber.SOLUTION: There is provided a p-tert-octylphenol-sulfur chloride co-condensed resin obtained by reacting 1.2-1.8 mol of sulfur monochloride with 1 mol of p-tert-octylphenol, having 25-34 wt.% of a sulfur content in the resin, and usable as a resin curing agent.

Description

The present invention relates to a p-tert-octylphenol sulfur chloride cocondensation resin that can be used as a resin cross-linking agent that improves viscoelastic properties without lowering the breaking properties of rubber and its application.

Alkylphenol / sulfur chloride co-condensation resins have been used as rubber cross-linking agents for resins that change to sulfur, and among them, p-octylphenol sulfur chloride co-condensation resins are known to have excellent processing performance and adhesion. It has been. (Patent Document 1)

In recent years, from the viewpoint of environmental protection, there has been a demand for improvement in fuel consumption (that is, reduction in fuel consumption) of automobiles. Various methods are known for improving the fuel efficiency of automobiles, and one of them is to change the characteristics of tires. To that end, it is necessary to improve the viscoelastic characteristics of rubber used in tires. Among them, a value called loss tangent (tan δ) has attracted attention, and this value is being reduced. (For example, Patent Documents 2 and 3) In these patent documents, an alkylphenol / sulfur chloride cocondensation resin is used in place of sulfur as a crosslinking agent in order to reduce tan δ. -When the physical properties of the rubber using the sulfur chloride co-condensation resin were confirmed, it was found that there was a problem that the breaking characteristics deteriorated.

JP 58-13648 A JP 2009-138148 A JP 2010-95670 A

An object of the present invention is to add p-tert-octylphenol chloride useful as a resin cross-linking agent having a feature that when added to rubber, viscoelastic properties are improved as compared with the case where sulfur is used without impairing fracture properties. The object is to provide a sulfur co-condensation resin.

As a result of intensive studies to solve the above problems, the present inventors have obtained a resin obtained by reacting 1.2 to 1.8 mol of sulfur monochloride with 1 mol of p-tert-octylphenol, It has been found that the above problem can be solved by using a p-tert-octylphenol sulfur chloride cocondensation resin having a sulfur content of 25 to 34% by weight as the resin crosslinking agent.

According to the present invention, when added to rubber, p-tert-octylphenol which can be used as a resin crosslinking agent has the characteristics that viscoelastic properties are improved as compared with the case where sulfur is used, and at the same time, the breaking properties are not deteriorated. It becomes possible to provide a sulfur chloride co-condensation resin.

The present invention is described in detail below. Octylphenol used in the present invention refers to p-tert-octylphenol in the presence of various isomers. In the case of octylphenol substituted at the o-position and m-position, the co-condensation resin intended for the present invention is not obtained without reacting with sulfur monochloride, and when pn-octylphenol is used, the co-condensation resin is obtained. However, when this co-condensation resin is used as a cross-linking agent, as shown in the comparative example of the present application, the viscoelastic properties that are the effects of the present invention are not improved, which is not preferable.

Sulfur chloride used in the present invention refers to sulfur monochloride (S2Cl2). When sulfur dichloride (SCl2) is used, the sulfur content in the obtained p-tert-octylphenol sulfur chloride cocondensation resin cannot be made 25 to 34% by weight, which is not preferable. Further, sulfur monochloride is used in an amount of 1.2 to 1.8 mol per 1 mol of p-tert-octylphenol. When the amount is less than 1.2 mol, the viscoelastic properties are not improved even when the obtained cocondensation resin is used as a cross-linking agent. .

In the reaction of p-tert-octylphenol and sulfur monochloride, the reaction can be carried out using an organic solvent as necessary. Any organic solvent may be used as long as it does not cause side reactions with p-tert-octylphenol or sulfur monochloride and does not inhibit the reaction. For example, benzene, toluene, xylene, mesitylene, Heptane, cyclohexane, etc. can be used.

The reaction between p-tert-octylphenol and sulfur monochloride is usually carried out by adding (1) p-tert-octylphenol and (2) the organic solvent as necessary to the reaction vessel, and (3) sulfur monochloride for a certain period of time. (4) After that, it is carried out by stirring for a certain period of time. Hereinafter, these reaction conditions and procedures will be described in detail.

The temperature at which sulfur monochloride is added is usually 40 to 180 ° C, preferably 70 to 120 ° C. If the temperature is lower than 40 ° C, the reaction proceeds slowly, which is economically disadvantageous. If the temperature is higher than 180 ° C, decomposition tends to occur. Moreover, the addition mentioned here includes both an operation of intermittently charging into the reaction system such as dropping, and an operation of continuously charging into the reaction system while controlling the flow rate. Although the addition time varies depending on the reaction scale, it usually takes 1 to 12 hours. The addition time can be easily set by those skilled in the art by sequentially confirming the temperature change during the addition.

The reaction after the addition of sulfur chloride is usually carried out at 40 to 180 ° C, preferably 70 to 120 ° C. If the temperature is lower than 40 ° C, the reaction proceeds slowly, which is economically disadvantageous. If the temperature is higher than 180 ° C, decomposition tends to occur. Although reaction time changes with temperature, it is 1 to 10 hours normally. The reaction time can be easily set by those skilled in the art by measuring the remaining amount of unreacted p-tert-octylphenol or measuring the viscosity change of the reaction system.

The p-tert-octylphenol sulfur chloride cocondensation resin thus obtained needs to have a sulfur content of 25 to 34% by weight in the resin. When it is lower than 25% by weight, the viscoelastic properties are not improved, and when it is higher than 34% by weight, the breaking strength and the wear resistance are deteriorated.

The p-tert-octylphenol sulfur chloride co-condensation resin of the present invention can be applied to all rubbers capable of sulfur crosslinking. Natural rubber (NR), styrene butadiene rubber (SBR), polybutadiene rubber (BR), polyisoprene rubber ( IR), chloroprene rubber (CR), acrylonitrile-butadiene copolymer rubber (NBR), isoprene-isobutylene copolymer rubber (IIR), ethylene-propylene terpolymer (EPDM), and the like. Among these, it is suitably used for natural rubber (NR), styrene butadiene rubber (SBR), acrylonitrile-butadiene copolymer rubber (NBR), and polybutadiene rubber (BR). The amount of p-tert-octylphenol sulfur chloride cocondensation resin used in rubber is 0.5 to 50% of the p-tert-octylphenol sulfur chloride cocondensation resin of the present invention relative to 100 parts by weight of rubber. Part by weight, preferably 1 to 30 parts by weight, more preferably 1 to 20 parts by weight is used. When the amount is less than 0.5 parts by weight, the crosslink density tends to be low and the viscoelastic properties tend to be deteriorated.

When the p-tert-octylphenol sulfur chloride cocondensation resin of the present invention is blended and used in rubber, a compounding agent usually used in the rubber industry, for example, a filler such as carbon black, zinc oxide, stearic acid, oil In the range which does not impair the object of the present invention, etc. can be appropriately selected and blended, and as these blending agents, commercially available products can be suitably used.

The rubber composition containing 0.5 to 50 parts by weight of the p-tert-octylphenol sulfur chloride cocondensation resin in the present invention is suitably used for rubber products used for tires, hoses, tubes, gaskets, home appliance parts and the like. .

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

(Manufacture of each resin)
In the production of each resin, analysis was performed based on the following analysis conditions.

<Sulfur content>
About 0.01 g of sample (p-tert-octylphenol sulfur chloride co-condensation resin) was placed in 0.5 ml of 30% hydrogen peroxide solution and 5 ml of water with compressed oxygen using a flask with a stopcock, ignited, and then quickly turned on Put on and seal tightly. After the completion of combustion, the flask is washed with 20 mL of 2-propanol, 3 drops of tritium mixed indicator is added, and titrated with a 0.01 mol / L barium perchlorate solution, and the titer is set to A ml. The end point is when the liquid color changes from greenish yellow to slightly reddish brown. In addition, a blank test was separately performed for correction, and the titer at the blank test was set to B ml, and the sulfur content was determined by the following formula.
Sulfur content (% by weight) = [32.06 × (AB) × 0.01 mol / L factor of barium perchlorate solution] / (sample weighed amount (g) × 100)

The equivalent weights and weight times described in the production examples below are equivalent weights and weight times with respect to p-tert-octylphenol unless otherwise specified.

<Production Example 1 Synthesis of Resin A>
A 4-necked flask equipped with a reflux condenser and a thermometer was charged with 900 g (4.36 mol) of p-tert-octylphenol and 290 g of toluene, and 709 g of sulfur monochloride (5.25 mol, 1.2 equivalents) was placed in the flask. Is dropped in 5 hours while maintaining the internal temperature of 70-80 ° C., and the internal temperature is raised to 120 ° C. after the completion of the dropwise addition, and kept for 3 hours. The resulting reaction solution was concentrated under reduced pressure to obtain 1220 g of p-tert-octylphenol sulfur chloride cocondensation resin (referred to as resin A). The sulfur content in the resin A is shown in Table 1.

<Production Example 2 Synthesis of Resin B>
A 4-necked flask equipped with a reflux condenser and a thermometer was charged with 900 g (4.36 mol) of p-tert-octylphenol and 300 g of toluene, and 736 g (5.76 mol, 1.3 equivalents) of sulfur monochloride was placed in the flask. Is dropped in 5 hours while maintaining the internal temperature of 70-80 ° C., and the internal temperature is raised to 120 ° C. after the completion of the dropwise addition, and kept for 3 hours. The obtained reaction solution was concentrated under reduced pressure to obtain 1240 g of p-tert-octylphenol sulfur chloride cocondensation resin (referred to as resin B). The sulfur content in resin B is shown in Table 1.

<Production Example 3 Synthesis of Resin C>
A four-necked flask equipped with a reflux condenser and a thermometer was charged with 900 g (4.36 mol) of p-tert-octylphenol and 370 g of toluene, and 901 g (6.67 mol, 1.53 equivalents) of sulfur monochloride was placed in the flask. Is dropped in 5 hours while maintaining the internal temperature of 70-80 ° C., and the internal temperature is raised to 120 ° C. after the completion of the dropwise addition, and kept for 3 hours. The obtained reaction liquid was concentrated under reduced pressure to obtain 1300 g of p-tert-octylphenol sulfur chloride cocondensation resin (referred to as resin C). The sulfur content in the resin C is shown in Table 1.

<Production Example 4 Synthesis of Resin D>
A four-necked flask equipped with a reflux condenser and a thermometer was charged with 900 g (4.36 mol) of p-tert-octylphenol and 460 g of toluene, and 1119 g of sulfur monochloride (8.29 mol, 1.9 equivalents) was placed in the flask. While maintaining the internal temperature of 70-80 ° C., the solution is dropped in 7 hours, and after completion of the dropwise addition, the internal temperature is raised to 120 ° C. and kept for 3 hours. The obtained reaction solution was concentrated under reduced pressure to obtain 1400 g of p-tert-octylphenol sulfur chloride cocondensation resin (referred to as resin D). The sulfur content in Resin D is shown in Table 2.

<Production Example 5 Synthesis of Resin E>
A 4-necked flask equipped with a reflux condenser and a thermometer was charged with 900 g (4.36 mol) of pn-octylphenol and 290 g of toluene, and 709 g of sulfur monochloride (5.45 mol, 1.2 equivalents) was placed in the flask. Is dropped in 5 hours while maintaining the internal temperature of 70-80 ° C., and the internal temperature is raised to 120 ° C. after the completion of the dropwise addition, and kept for 3 hours. The obtained reaction liquid was concentrated under reduced pressure to obtain 1230 g of p-tert-octylphenol sulfur chloride co-condensation resin (referred to as resin E). The sulfur content in Resin E is shown in Table 2.

<Resin F>
A p-tert-octylphenol sulfur chloride cocondensation resin, V-200, manufactured by Taoka Chemical Industries, Ltd. was used as resin F as it was. The sulfur content in resin F is shown in Table 1.

<Production Example 6 Synthesis of Resin G>
A four-necked flask equipped with a reflux condenser and a thermometer was charged with 900 g (4.36 mol) of pt-octylphenol and 240 g of toluene, and 590 g (4.46 mol, 1.0 equivalent) of sulfur monochloride was placed in the flask. Is dropped in 5 hours while maintaining the internal temperature of 70-80 ° C., and the internal temperature is raised to 120 ° C. after the completion of the dropwise addition, and kept for 3 hours. After adding powder sulfur 85g to the obtained reaction liquid, it concentrated under pressure reduction and obtained 1240g of p-tert-octyl phenol sulfur chloride cocondensation resin (referred to as resin G). The sulfur content in resin G is shown in Table 2.

<Creation of rubber sheet for evaluation>
200 g of a rubber compound having the following composition was prepared by kneading at a set temperature of 40 ° C. for 10 minutes using a 6-inch open roll manufactured by Kansai Roll.
<Combination>
Styrene butadiene rubber (SBR) (JSR 1502 made by JSR) 70 parts butadiene rubber (BR) (Ube Industries BR150B) 30 parts silica (Tosoh Silica VN3) 50 parts carbon black (Showa Cabot) N330) 5 parts by weight silane coupling agent (Degussa Si69) 5 parts by weight anti-aging agent (Ouchi Shinsei Chemical Co., Ltd. Nocrack 6C) 2 parts by weight zinc oxide (manufactured by Sakai Chemical) 3 parts by weight stearic acid (Japan) 2 parts by weight vulcanization accelerator (CZ-G made by Ouchi Shinsei Chemical Co., Ltd.) 3 parts by weight insoluble sulfur (Crytex HS OT-20 made by Flexis) 2 parts by weight p-tert-octylphenol sulfur chloride cocondensation 2 parts by weight of resin

<Rubber physical property evaluation method>
(Tensile test)
Based on JIS K6251, the strength at break (MPa) was measured using a dumbbell-shaped No. 3 test piece.
(Rolling resistance; tan δ (70 ° C))
Dynamic viscoelasticity was measured with a dynamic viscoelasticity measuring device manufactured by Seiko Instruments Inc. at an initial strain of 1%, an amplitude of ± 0.2%, and a frequency of 10 Hz, and tan δ at a temperature of 70 ° C. was determined. The test piece was cross-linked at 160 ° C. for 15 minutes.

<Rubber properties evaluation criteria>
The evaluation results when using the respective resin cross-linking agents when the evaluation results of the reference examples using sulfur as the resin cross-linking agent were set to 100 were relatively described. In addition, the evaluation results were visualized based on the following evaluation criteria.
Tb (strength at break: value related to break characteristics. The higher the value, the better the break characteristics)
Reduction within 5% compared to the reference example: ○
Lower than 5% and within 10%: △
Decrease by 10% or more: ×
tan δ (value relating to viscoelastic properties. The lower the value, the better the viscoelastic properties)
Increased compared to the reference example: ×
Less than 5% drop:
Less than 5%, less than 10%: ○
Decrease by 10% or more: ◎

<Table 1>

<Table 2>

Claims (2)

A resin obtained by reacting 1.2 to 1.8 mol of sulfur monochloride with 1 mol of p-tert-octylphenol, wherein the sulfur content in the resin is 25 to 34% by weight. P-tert-octylphenol sulfur chloride co-condensation resin. A rubber composition comprising 0.5 to 50 parts by weight of the p-tert-octylphenol sulfur chloride cocondensation resin according to claim 1.