JPH0229425A - Polyether copolymer - Google Patents

Abstract

PURPOSE:To produce the title copolymer having high heat resistance and low- temperature resistance and excellent in lubricant resistance by copolymerizing propylene oxide with ethylene oxide in a specified ratio and a small amount of epibromohydrin. CONSTITUTION:Propylene oxide (A) is blended with ethylene oxide (B) and epibromohydrin (C) in the proportions of 56-89, 10-40 and 1-4mol%, respectively, and copolymerized in the presence of a polymerization catalyst, thereby producing a rubbery solid polyether copolymer having a reduced viscosity of 1.0-6.0 as measured in 0.1% monochlorobenzene solution at 80 deg.C. Since the component (A) is copolymerized with the component (B) in a prescribed ratio, the oil resistance is improved, and further since the product is copolymerized with a small amount of the component (C), crosslinking can proceed at a practical reaction rate and therefore a rubber having excellent performance balance and high lubricant resistance and oil resistance can be obtained.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a novel polyether copolymer, and more specifically, the present invention relates to a novel polyether copolymer that exhibits heat resistance and
Ethylene oxide - propylene oxide - which is a rubber material with an excellent performance balance of cold resistance and lubricant resistance.
This invention relates to epibromohydrin copolymers.

(Prior art) Among polyether copolymer rubbers, epichlorohydrin is the main constituent, such as epichlorohydrin-edylene oxide copolymer or shrimp chlorohydrin-edylene oxide allyl glycidyl ether copolymer. Copolymer rubber (hereinafter referred to as epichlorohydrin copolymer rubber) is heat resistant.

It is widely used as an oil-resistant rubber material with an excellent balance of performance such as oil resistance and cold resistance. Particularly oil resistant.

A major feature of these polyether rubbers is that they have both cold resistance and cold resistance, which is not achieved by other oil-resistant rubbers having a carbon skeleton main chain.

Conventionally, as a method for evaluating the oil resistance of rubber, the volumetric swelling rate with respect to oil components has been mainly adopted.For example, the degree of volumetric swelling with respect to 0 base oil such as JIS No. 2 oil is used to evaluate the durability against lubricating oils.

However, in recent years, with the aim of improving the performance of lubricating oils, extremely high-level and multi-ω chemicals (hereinafter referred to as additives) have been added as essential constituents of lubricating oils.
Due to these chemical reactivity, even conventional rubbers with excellent oil resistance, including the above-mentioned epichlorohydrin copolymer rubber, have problems in durability.

In the case of epichlorohydrin copolymer rubber, the main cause is thought to be that side chain chlorine, which provides oil resistance, reacts with additives and accelerates deterioration. Therefore, one possible countermeasure is to reduce the epichlorohydrin-containing layer while taking into consideration the balance with oil resistance. However, since side chain chlorine is also used as a crosslinking point for heat-resistant molded products, excessively reducing the chlorine content lowers the crosslinking rate and causes problems in practical processability.

On the other hand, propylene oxide-allyl glycidyl ether copolymer rubber is known as a polyether copolymer rubber that does not contain any chlorine, but it has excellent low-temperature flexibility, which is a characteristic of polyether rubber. However, the problem is that it has poor oil resistance and heat resistance.

Under these circumstances, there has been a desire for an oil-resistant rubber that maintains an excellent balance of performance and has a high degree of lubricating oil resistance.

(Purpose of the invention) Benefiting from the above points, the inventors have achieved a high degree of heat resistance.

We conducted intensive research with the aim of obtaining a new polyether rubber that maintains cold resistance and is resistant to recent high-performance lubricants. As a result, by copolymerizing propylene oxide with a specific ratio of ethylene oxide to improve oil resistance, and further copolymerizing a small amount of more reactive epibromhydrin as a crosslinking point, we were able to crosslink at a practical reaction rate. 1n, and that the novel propylene oxide ethylene oxide-epibromohydrin copolymer rubber thus obtained can fully achieve the above objects, and have completed the present invention. be.

(Advanced composition of the invention) The present invention provides that the composition ratio of the seven-mer exchange port is ethylene oxide 1
A polyether containing 0 to 40 mol% of propylene oxide, 56 to 89 mol% of propylene oxide, and 1 to 4 mol% of ebibromine, having a reduced viscosity measured in a 0.1% monochlorobenzene solution at 80°C. It is a rubbery solid polyether copolymer having a polyether copolymer of 1.0 to 6.0.

The copolymer of the present invention is produced by ring-opening polymerization of each of ethylene oxide, propylene oxide, and epibromohydrin using a catalyst.

As the ring-opening polymerization catalyst, those generally known as epichlorohydrin high polymerization catalysts are used, such as a catalyst system mainly containing aluminum and an organotin-phosphoric acid ester condensate catalyst system. Examples of organoaluminum catalysts include trialkylaluminum-water-acetylacetone catalysts and aluminum alkoxide-phosphate ester condensates, and examples of organotin-phosphate ester composite catalysts include those described in U.S. Patent No. 3,773,694 by the present applicant. For example, mention may be made of the catalyst 2 described in the book, dibutyltin oxide-tributyl phosphate condensate.

Polymerization reactions using these catalysts are carried out in the presence or absence of a solvent, usually at a temperature in the range of 0 to 60° C., with stirring or shaking. The amount of the catalyst used is suitably in the range of 0.01 to 5 parts by weight per 100 parts by weight of hexamer. Examples of solvents include aliphatic hydrocarbons such as hexane and heptane;
Aromatic hydrocarbons such as bempine and 1-toluene, halogenated hydrocarbons such as methylene chloride and chlorobenpine, or di-2-chlorinated hydrocarbons such as nitromethane and nitrobempine are used. It is desirable to reduce the water content of the polymerization reaction system as much as possible.

The polymer copolymer of the present invention produced in this manner is a polyether copolymer in the form of a rubber solid.

In the composition of this copolymer, the ethysine oxide content is 1
If it is less than 0 mol %, the swelling resistance to lubricating oil will be reduced and the properties as an oil-resistant rubber will be lost, and if it exceeds 40 mol %, the water resistance will be sharply reduced and the heat resistance will be reduced. Conversely, if the propylene oxide content exceeds 89 mol %, the swelling resistance against lubricating oil will decrease, and if it is less than 56 mol %, the water resistance and heat resistance will decrease. Furthermore, if the epibromohydrin content is less than 1 mol%, the crosslinking function will decrease, and if it exceeds 4 mol%, the durability against additives will decrease.

If other shrimp halohydrins are used instead of shrimp bromohydrin, shrimp fluorohydrin, for example, is expensive and has poor crosslinking reactivity. With shrimp iodohydrin, it is difficult to obtain a high-quality copolymer. Furthermore, as described above, shrimp chlorhydrocane has a poor performance balance between crosslinking ability and additive resistance. Therefore, an excellent performance balance of heat resistance, cold resistance, lubricating oil resistance, and water resistance can only be achieved by using a copolymer having the components and composition ratios within the above ranges.

In addition, 0.1% of this copolymer at 80°C
] The reduced viscosity measured with Roben L solution is 1.0 to 6.0.
The practically preferred range is 1.0 to 5.0.

The copolymers of the present invention having these polymer compositions are easily vulcanized with conventional vulcanizing agents for halogen-containing rubbers, such as polyamines and their derivatives, thioureas, or polymercapto compounds.

Example 1 10.0 g of dibutyltin oxide and 23.4 g of tributyl phosphate were placed in a 3-tube flask equipped with a thermometer, distillation equipment, and a stirrer, and heated at 250°C for 20 minutes with stirring under a nitrogen stream. The solid polymerization catalyst was removed by cooling.

The hand reaction was carried out at 44 parts V and at a temperature h1. 20.Equipped with a pressure gauge, a sample introduction pipe and a nitrogen introduction pipe. It was carried out in a stainless steel reactor of Q capacity. Kirin9ooo to nitrogen substitute inside the reactor
After sequentially adding 117 g of I-pibromhydrin, 1860 g of propylene oxide and 376 g of ethylene oxide, 5.0 g of the above polymerization catalyst was added, and the mixture was heated to 15° C. without stirring.
It reacted for 5 hours.

After terminating the reaction by adding 50% of water to the reaction mixture, the solution portion was decanted, the polymer was repeatedly washed with hexane, further washed with a needle, and finally 2,2'methylenebis(4-methyl- After impregnating it in ether 800d containing 1.0 g of 6-tertiary buburnoenol, the needle was decanted, dried at 40°C under reduced pressure for 12 hours, and rubbery polymer 1290 () was soaked for 1 watt. (Yield 55%).

A 0.1% solution of this polymer in monochlorobenzene at 80°C.
-' (The measured reduced viscosity was 3.4. Also, the composition ratio of this polymer in terms of 7-mer was analyzed by elemental analysis and proton nuclear magnetic resonance spectroscopy.
3 mol%, propylene oxide 75 mol% and shrimp bromohydrin 2 mol%.

The polymerization reaction conditions and properties of the isolated copolymers are summarized in Table 1.

Examples 2 to 3 Ternary copolymers having different composition ratios were obtained in the same manner as in Example 1. The polymerization reaction conditions and properties of the isolated copolymer are shown in Table 1. In the table, the reduced viscosity of the copolymer at 80°C is 0.
．． Indicates the value measured with 1% monochloroben U solution,
The monomer exchange crude ratio is a calculated value based on elemental analysis and proton nuclear magnetic resonance spectrum analysis of the copolymer.

Comparative Examples 1 to 6 Terpolymer copolymers having the composition ratios shown in Table 1 were obtained in the same manner as in Example 1. The polymerization reaction conditions and the properties of the isolated copolymer are also shown in Table 1.

Example 4 The copolymer obtained in Example 1-3 above was
00 parts (same for 11 or less), 1 part of stearic acid, 40 parts of FEF carbon, 5 parts of red lead, 1 part of nickel dibutyldidi A carbamey 1, and 1 or 2 parts of 2-mercaptoimidacillin. After blending and rolling, heat at 160'C for 2
After vulcanization for 0 minutes, the physical properties were measured according to JIS K6301, and the results are shown in Table 2.

Further, the copolymers obtained in Comparative Examples 1 to 6 were tested in the same manner as in Example 4, and the results are shown in Table 2.

From these test results, the polyether composite of the present invention is a rubber material with excellent performance balance,
Deviation from the scope of the invention will result in various disadvantages. For example, if there is too little ethylene oxide, oil resistance will decrease;
If it is too large, water resistance will decrease. It can be seen that if the amount of epibromohydrin is too small, vulcanization will not be possible, and if it is too large, the embrittlement and deterioration will be significantly increased (the elongation change rate in the lubricating oil resistance test will be too high).

(Effects of the Invention) The composite of the present invention improves oil resistance by avoiding copolymerization of 56 to 89 mol% of propylene oxide with 10 to 40 mol% of ethylene oxide using an L-summer exchange valve, and improves oil resistance by copolymerizing 56 to 89 mol% of propylene oxide with 10 to 40 mol% of ethylene oxide. An ethylene oxide-propylene oxide-epibromohydrin ternary conjugated polyether rubber having a practical crosslinking rate by copolymerizing 1 to 4 mol% of It is possible to obtain a rubber material that has good durability and has a good balance of heat resistance and cold resistance. Furthermore, since conventional vulcanizing agents for halogen-containing rubber can be applied, it has great industrial value.

Claims (1)

[Claims] The composition ratio in terms of monomer is ethylene oxide 10-40
mol%, 56-89 mol% propylene oxide and 1-4 mol% epibromohydrin, having a reduced viscosity of 1.0-6 measured in 0.1% monochlorobenzene solution at 80°C. A rubbery solid polyether copolymer having a molecular weight of .0.