JPH0218323B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a high molecular weight copolymer of 1-acetoxy-1,3-butadiene (hereinafter abbreviated as 1-ABD). More specifically, the number average molecular weight is 22000.
~1000000 1-ABD and conjugated diene and/or
Or it relates to a copolymer with an ethylenically unsaturated compound. Conventionally, 1-ABD copolymers have been produced by bulk or solution polymerization using azobisisobutyronitrile or benzoyl peroxide as an initiator, or by emulsion polymerization at 60 to 90°C using persulfate as an initiator. Conjugated diene, styrene,
Copolymers with ethylenically unsaturated compounds such as methyl methacrylate, vinyl acetate, and acrylonitrile have been obtained. (e.g. Macromol
Chem., 176(2), 341, 1975) However, the number average molecular weight of the copolymer obtained by the conventional method is 20,000 at most because 1-ABD itself is susceptible to chain transfer reactions. It is stated in Further, according to additional tests by the present inventors, especially when 1-ABD is 10% by weight or more, even the above polymerization method has a number average molecular weight of
It was found that a copolymer of 20,000 was not obtained. 1-ABD is a conjugated diene with a polar group,
This copolymer can be used in various ways as a new polymer material, but conventionally available relatively low molecular weight copolymers are limited in terms of mechanical strength, adhesive strength, etc. When considering applications such as adhesives, it has been desired to obtain copolymers with higher molecular weights than conventional ones. The present inventors have investigated the conventionally obtained 1-ABD copolymer containing 10% by weight or more of 1-ABD.
We conducted intensive studies to obtain a copolymer with a higher molecular weight than ABD copolymers, and found that by lowering the polymerization temperature, we could obtain a copolymer with a much higher molecular weight than conventionally obtained copolymers. It was discovered that a polymer was obtained and that this copolymer had excellent oil resistance, and based on this knowledge, the present invention was accomplished. That is, the present invention provides a copolymerization product of 1-ABD and at least one conjugated diene and/or ethylenically unsaturated compound, which has a number average molecular weight of
A copolymer of 1-ABD of 22,000 to 1,000,000 is provided. The present invention will be explained in detail below. 1-ABD, a monomer used in the present invention
is obtained by acetoxylating butadiene in the presence of a noble metal catalyst such as palladium, but it can also be obtained by heating crotonaldehyde in the presence of acetic anhydride and an alkali metal acetate. 1-ABD obtained by these reactions is a mixture of cis-form and trans-form, but the monomer used in the present invention may be a cis-form, a trans-form alone, or a mixture thereof. do not have.
It goes without saying that it may also contain impurities such as water and organic solvents to an extent that does not cause any inconvenience to the polymerization. At least one of a conjugated diene and an ethylenically unsaturated compound is selected as the copolymerizable monomer.
The conjugated diene is preferably a conjugated diene having 4 to 6 carbon atoms in terms of polymerizability, and among these, butadiene, isoprene, piperylene, and chloroprene are particularly preferred. Preferred ethylenically unsaturated compounds include olefins having 2 to 5 carbon atoms, and among them, ethylene is preferred from the viewpoint of polymerizability.
In addition, acrylic acid, methacrylic acid, and their esters are included in ethylenically unsaturated compounds in a broad sense, but methyl esters with 1 carbon number to lauryl esters with 12 carbon atoms of acrylic acid and methacrylic acid are particularly preferred, and among these, methyl esters are preferred. , ethyl, propyl, n-butyl, sec-butyl, t-
Butyl, 2-ethylhexyl and hydroxyethyl ester are preferred from the viewpoint of polymerizability. Other preferable ethylenically unsaturated compounds from the viewpoint of polymerizability include styrene, vinyl acetate, acrylonitrile, methacrylonitrile, allyl acetate, methalylacetate, acrylamide, and methacrylamide. Only one type of these copolymerizable monomers may be copolymerized with 1-ABD, but two or more types may be copolymerized with 1-ABD.
It can also be copolymerized with ABD. The copolymerization composition of these copolymerization monomers and 1-ABD is usually selected within the range of 10 to 99.9% by weight of 1-ABD in order to take advantage of the characteristics such as oil resistance of the 1-ABD copolymer. In order to take advantage of the characteristics of each copolymerized monomer as a polymer, it is preferable that the amount of each copolymerized monomer be within the range of 1% to 90% by weight, and further 5% to 80% by weight of the copolymerized monomer. It is preferable because the characteristics become clearer, and 20
Even more preferred are weight % to 70 weight %. An example of a method for producing a high molecular weight copolymer obtained by copolymerizing these copolymerizable monomers with 1-ABD will be described. The polymerization is carried out at a temperature of -50 to 50°C, preferably -10 to 45°C, more preferably -5 to 40°C, which is lower than the conventional temperature of 60 to 90°C. Therefore, it is preferable to use a so-called redox system as a polymerization initiator. For example, monomers are emulsified in an aqueous system in the presence of an appropriately selected surfactant, and peroxide is used as a polymerization initiator and ferrous iron is used as an activator. By carrying out polymerization at the above temperature using a reducing agent such as a salt, an electrolyte to facilitate the reaction, a PH regulator, a molecular weight regulator, etc., polymerization with a number average molecular weight of 22,000 or more, which has never been obtained before, can be achieved. 1-ABD copolymers can be produced. The surfactant may be any of the so-called anionic, nonionic, and anionic nonionic surfactants, and of course a mixture of these may be used without any particular limitation, but it is usually 1-ABD and 100% by weight of the copolymerized monomer. 0.5 to 10 parts by weight per part. The peroxide used as a polymerization initiator is usually hydrogen peroxide, cumene hydroperoxide, para-menthane hydroperoxide, etc., and preferably per 100 parts by weight of 1-ABD and copolymerizable monomer.
0.001 to 10 parts by weight are used. As the ferrous salt, ferrous sulfate is usually used.
−0.001 per 100 parts by weight of ABD and copolymerized monomer
~0.5 part by weight is used. The molecular weight of the copolymer can be appropriately changed using a molecular weight regulator, and linear alkyl mercaptan, carbon tetrachloride, diisopropyl xantogen disulfide, etc. are preferably used as the molecular weight regulator. It is usually used in an amount of 0.001 to 10 parts by weight per 100 parts by weight of 1-ABD and copolymerized monomer, depending on the degree of copolymerization. As the electrolyte, potassium chloride, potassium phosphate, sodium phosphate, sodium sulfate, etc. are added as appropriate. Water is a monomer copolymerized with 1-ABD
It is usually used in an amount of 50 to 500 parts by weight per 100 parts by weight, but it does not have to be pure water and may contain organic solvents, metal salts, etc. to an extent that does not cause any inconvenience to the polymerization. In addition, instead of using a redox polymerization initiator, ordinary persulfates such as potassium persulfate, sodium persulfate, and ammonium persulfate are used.
It is also possible to polymerize at ~50°C, but if the temperature
When the temperature exceeds 50°C, polymerization stability deteriorates, and not only is it difficult to obtain a product with a high molecular weight, but gelation progresses. In such a polymerization, 1-ABD, a copolymerizable monomer, a polymerization aid, etc. may be added all at once, and it is of course possible to use an inkjet method if necessary. Further, polymerization aids and the like are used as necessary, and it goes without saying that two or more kinds may be used in combination. In addition, polymerization may be carried out up to 100% polymerization rate,
In order to prevent gelation, etc., a polymerization terminator or the like may be added during the reaction to stop the reaction. Also, in bulk or solution radical polymerization
Azo initiators that decompose relatively quickly at temperatures below 50°C, such as 2,2'-azobis(4-methoxy-
2,4-dimethylvaleronitrile), 2,2'-azobis-(2,4-dimethylvaleronitrile), etc., at a low polymerization initiator concentration, it is possible to achieve a copolymer with a high molecular weight that has not been previously obtained. It is also possible to produce combinations. The copolymer can be recovered from the reaction system after the completion of the polymerization reaction by various means. For example, the copolymer can be recovered by adding the above reaction system to a large amount of methanol and precipitating the copolymer.
A purified copolymer can be obtained by thoroughly washing with methanol and drying. The 1-ABD copolymer of the present invention has a number average molecular weight of
22000 or more, but usually 22000-1000000
It is easy to manufacture 22,000 to 500,000 pieces. Furthermore, since the 1-ABD copolymer of the present invention is used, the number average molecular weight is 50,000.
~1000000 is preferred. The 1-ABD copolymer of the present invention can be crosslinked with sulfur, has excellent practical strength and oil resistance, and is also excellent as an adhesive for glass, paper, wood, etc. The number average molecular weight of the 1-ABD copolymer of the present invention can be determined by dissolving the copolymer in an appropriate solvent selected depending on the copolymer composition, such as acetone or tetrahydrofuran, and performing GPC (gel permeation chromatography). ). The standard sample for the number average molecular weight in this case is polystyrene, and the number average molecular weight in the present invention is limited to the number average molecular weight measured in this manner in terms of polystyrene. Next, the present invention will be specifically explained using examples. Examples 1 to 15 In a glass pressure-resistant bottle with a capacity of 500 c.c., the first
Total weight of 1-ABD and copolymerized monomers as shown in the table: 100 g, sodium dodecylbenzenesulfonate 6 g, water 200 g, sodium ethylenediaminetetraacetate 0.1 g, ferrous sulfate 0.1 g, sodium formaldehyde sulfoxylate 0.1 g,
Prepare 1.0g of paramenthane hydroperoxide,
Polymerization was carried out at 10°C for 15 hours. Then N,N-diethylhydroxylamine
1.0 g was added to stop the polymerization. In both cases, an emulsion containing almost no coagulated substances was obtained. This emulsion was added dropwise to the methanol from step 3 under stirring to precipitate the copolymer. The copolymer was thoroughly washed with methanol, and the copolymer was thoroughly washed with methanol at 50℃ under vacuum. Dry. Table 1 shows the polymerization rate, the copolymer composition determined by elemental analysis of the copolymer, the glass transition point, and the number average molecular weight determined by GPC.

【table】

[Table] Examples 16 to 19 Same as Example 1, except that in Example 1, paramenthane hydroperoxide was used as 0.3 g, and tertiary lead decyl mercaptan was charged as shown in Table 2 and polymerized for 50 hours at 3°C. It was polymerized and purified in the same manner. The results are shown in Table 2.

[Table] Examples 20 to 23 Examples except that in Example 6, 1.0 g of paramenthane hydroperoxide was replaced with 0.1 g of cumene hydroperoxide, and tertiary lead decyl mercaptan was charged as shown in Table 3 and polymerized at 3°C for 48 hours. Polymerization was carried out in the same manner as in 6. The results are shown in Table 3.

[Table] Example 24 1-ABD30g, styrene 20g, butadiene
Polymerization and purification were carried out in the same manner as in Example 1, except that 50 g was charged. The polymerization rate is 90.1%, and the number average molecular weight is
It was 265,000. Example 25 1-ABD50 under nitrogen in a 600 c.c. glass pressure bottle
g, butyl acrylate, 50 g, water, 200 g, sodium dodecylbenzenesulfonate, 5 g, ammonium persulfate, 0.1 g, and tertiary decyl mercaptan, 0.2 g, and reacted at 38° C. for 29 hours. An emulsion with a polymerization rate of 72.1% and almost no coagulum was obtained, and the number average molecular weight of this copolymer was 128,000. Example 26 In Example 25, ammonium persulfate was added to 2,
Example 25 except that 1.0g of 2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) was used.
It was polymerized in the same way. An emulsion with a polymerization rate of 74.9% and almost no coagulum was obtained, and the number average molecular weight of this copolymer was 116,000. Comparative example 1 20% of benzene under nitrogen in a 100 c.c. glass pressure bottle
g, 1-ABD10g, styrene 100g and 2,
0.1 g of 2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) was charged and polymerized at 60°C for 20 hours. The obtained copolymer was a colorless and transparent liquid, and the reaction rate was 66.1%. The number average molecular weight of this copolymer was measured and found to be 8,200.

Claims (1)

[Claims] 1 1-acetoxy-1,3-butadiene 10-99.9
A copolymer of 1-acetoxy-1.3-butadiene having a number average molecular weight of 22,000 to 1,000,000, which is obtained by copolymerizing % by weight and at least one conjugated diene and/or ethylenically unsaturated compound.