JPS6160089B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for producing a novel aldehyde reaction product that is different from conventionally known phenolic resins and is useful as a reinforcing agent for rubber. (Prior Art) Several polymers or alkylation products derived from alkenylphenols have been proposed. For example, in Organic Synthetic Chemistry Vol. 34, page 1000 (1976), a polymer of isopropenylphenol is reported. However, a polymer of isopropenylphenol is a polymer produced by a reaction between isopropenyl groups, as shown in formula [A], and a polymer in which isopropenyl groups are alkylated to the other phenol nucleus is not produced. Furthermore, JP-A-55-145626 describes the alkylation reaction of alkylphenols, but as shown in formula [B], it is an alkylation reaction with phenol, and the polymer having repeating units is I haven't gotten it. (In the formula, m is 1 or 2) Furthermore, British Patent No. 741446 (1955)
In addition to p-cyclopentenylphenol or o-cyclopentenylphenol being synthesized by the alkylation reaction of cyclopentadiene and phenol, the formula [C] Although a compound represented by the following has been submitted, there is no mention of a polymer having a repeating unit represented by the following general formula []. On the other hand, phenolic resins are known as aldehyde reaction products useful as reinforcing agents for rubber. (Object of the invention) The present invention utilizes a polymer different from the conventional alkenylphenol-derived polymer or alkylated product as described above, reacts the polymer with aldehydes, and produces a conventional phenol The present invention provides a method for producing a novel aldehyde reaction product different from a resin. (Structure of the invention) The present invention is based on the general formula [] (wherein, R is hydrogen, halogen, nitro group, alkyl group having 1 to 5 carbon atoms, or alkoxy group, and m and n are each 1 or 2). Among them, m+n is 3 or less, and at least two of the two o-positions and p-positions with respect to the OH group are bound to hydrogen (hereinafter referred to as polyfunctional cyclopentenylphenol compounds), or the polyfunctional cyclopentenylphenol compound Among the functional cyclopentenyl phenol compounds and the cyclopentenyl phenol compounds represented by the above general formula [], m+n is 2 to 4 and hydrogen is present at only one of the two o-positions and p-positions with respect to the OH group. is bonded to the other substituents (hereinafter referred to as a monofunctional cyclopentenylphenol compound) by an alkyl addition reaction. The present invention relates to a method for producing a characteristic cyclopentenylphenol resin. Next, the cyclopentenylphenol polymer in the present invention will be explained. The cyclopentenylphenol polymer in the present invention has the general formula [] (However, in the formula, R and n are the same as in the general formula [], and the cyclopentane ring is bonded to the phenol nucleus at the o-position or p-position with respect to the OH group, has repeating units represented by (at the 1- and 2-positions or at the 1- and 3-positions). The cyclopentenylphenol compound represented by the general formula [] is the o-position or p-position of the phenol nucleus.
At least one of the - positions is hydrogen. This is because the cyclopentenyl group attached to the phenol nucleus forms an otom of another phenol nucleus through an alkylation reaction.
This is necessary because high molecular weight compounds are produced by addition at the - or p-positions. More specifically, in the present invention, the cyclopentenylphenol polymer has an o
Since hydrogen bonded to the - or p-position is required, a polyfunctional cyclopentenyl phenol compound is used as an essential component among the cyclopentenyl phenol compounds represented by the general formula []. An alkyl addition reaction using only a monofunctional cyclopentenylphenol compound is not preferred because the above-mentioned functional groups are consumed by the addition reaction.
The monofunctional cyclopentenyl phenol compound and the polyfunctional cyclopentenyl phenol compound are contained as components in the cyclopentenyl phenol polymer in a molar ratio of 1/5 to 0/1. is preferable, particularly preferably 1/3 to 0/1, and most preferably 1/2 to 0/1. If the monofunctional component is too large, the number of functional groups in the cyclopentenylphenol polymer will be too small. Among the above-mentioned cyclopentenylphenol-based polymers, polyfunctional ones include o-cyclopentenylphenol, p-cyclopentenylphenol, etc., and monofunctional ones include 2-methyl-
There are 4-cyclopentenylphenol, 2-cyclopentenyl-4-methylphenol, 2,4-cyclopentenylphenol, etc. As cyclopentenylphenol compounds, monoalkyl substituted compounds other than those listed here are shown in Table 1. There are things to show.

[Table] In Table 1, propyl group is either n-propyl group or isopropyl group, and butyl group is n-propyl group.
It is either a butyl group, a sec-butyl group or a tert-butyl group, and a pentyl group is an n-pentyl group or any of other structural isomers. An acidic catalyst is used in carrying out the alkyl addition reaction of these cyclopentenylphenol compounds. Acidic catalysts include sulfuric acid, phosphoric acid, nitric acid,
Examples include mineral acids such as hydrochloric acid and paratoluenesulfonic acid, as well as Lewis acids such as boron trifluoride, aluminum chloride, and molybdenum chloride. The amount of these catalysts varies depending on the type of catalyst used, but is preferably 0.05 to 5% by weight, particularly 0.1 to 2.0% by weight based on the cyclopentenylphenol compound.
Weight percent is preferred. When the amount of catalyst is less than 0.05% by weight, the reaction is slow, the molecular weight of the product is small, and a large amount of raw material monomer tends to remain. However, the amount of neutralized salt generated tends to be large. The reaction temperature varies depending on the type of catalyst used and the amount of catalyst, but is preferably 0°C or more and 200°C or less,
Particularly preferred is 50°C or higher and 170°C or lower. When the reaction temperature is low, such as less than 0°C, the reaction tends to be slow, and when the reaction temperature exceeds 200°C, a reaction in which the cyclopentenyl group and other substituents are eliminated tends to occur. In the reaction, the solvent does not need to be used if the reaction is carried out at a temperature higher than the melting temperature of the cyclopentenylphenol compound, but when used, aromatic solvents such as benzene, toluene, xylene, chloroform, carbon tetrachloride, Examples include chlorine-containing solvents such as chlorobenzene, and ethyl ether. Furthermore, a phenol compound can be added to adjust the molecular weight of the cyclopentenylphenol polymer obtained in the present invention and to modify the obtained polymer. Examples of the phenol compound include phenol, an alkylphenol having an alkyl group having 1 to 6 carbon atoms, a bisphenol compound, and the amount of these compounds to be added is appropriately determined depending on the molecular weight of the polymer to be obtained. is 0 to 20% by weight based on the cyclopentenylphenol compound.
is preferred. If this value is exceeded, generally only a polymer with a small molecular weight can be obtained. The cyclopentenylphenol polymer after the reaction contains the acidic catalyst used in the reaction and unreacted monomers, so if purification is necessary, the following purification method is employed. To remove the acidic catalyst used in the reaction, the produced cyclopentenylphenol polymer is dissolved in a solvent such as acetone, tetrahydrofuran, methanol, or dioxane, and a base such as sodium hydroxide, potassium hydroxide, or sodium carbonate is added to this. Neutralize by adding a chemical compound. After neutralization, the neutralized salt is removed by filtration, and the solvent used is then distilled off. In addition, to remove unreacted monomers, neutralization and
After desolvation, unreacted monomers are distilled off under reduced pressure, or after the above neutralization, a poor solvent such as n
- By adding hexane, cyclohexane, etc., only the polymer is obtained as a precipitate at the bottom of the container. The above cyclopentenylphenol polymer is
Can be reacted with aldehydes. The reaction may be carried out in the presence of a basic catalyst or in the presence of an acidic catalyst, and the reaction may be acidified after the reaction in the presence of a basic catalyst. Examples of the aldehydes include formaldehyde and acetaldehyde, which are used as an aqueous solution, solid, or solution in an organic solvent. Examples of the above-mentioned base catalysts include oxides or hydroxides of alkali metals such as Na and K, alkaline earth metals such as Ca and Ba, amines such as dimethylamine, trimethylamine, and triethylamine, and ammonia. Mineral acids such as sulfuric acid, phosphoric acid, nitric acid, and hydrochloric acid, para-toluenesulfonic acid, etc. are used. The amount of the basic catalyst used is preferably 0.01 to 1% by weight, and the amount of the acidic catalyst used is preferably 0.05 to 0.1% by weight, based on the cyclopentenylphenol polymer. When reacting in the presence of a basic catalyst and then under acidic conditions, the basic catalyst is 0.01 to 1% by weight.
The acidic catalyst is preferably used in an additional amount of 0.05 to 1% by weight as necessary to neutralize the basic catalyst. The reaction temperature is preferably 80 to 120°C. In addition, as a reaction solvent, benzene, toluene,
Aromatic solvents such as xylene, chlorine-containing solvents such as chloroform, carbon tetrachloride, and chlorobenzene, ethyl ether, and the like can be used. The aldehyde is preferably used in an amount of 0.15 to 2 moles, particularly preferably 0.3 to 2 moles, per mole of the polyfunctional cyclopentenyl phenol compound component in the cyclopentenylphenol polymer. If the amount of aldehydes is too small, a sufficient amount of aldehyde bonds cannot be obtained, and if it is too large, unreacted aldehydes will increase. In addition, when the amount of the polyfunctional cyclopentenyl phenol compound component in the cyclopentenyl phenol polymer is small, it is preferable to use the aldehyde in an amount equivalent to or more of the polyfunctional component. (Example) An example of synthesis of a cyclopentenylphenol polymer will be shown. Synthesis Example 1 50g of 4-cyclopentenylphenol was placed in a 100ml three-necked flask equipped with a thermometer and stirrer, heated to 150°C, and 0.5g of para-toluenesulfonic acid was added.
g was added thereto, and the mixture was heated and stirred for 2 hours and 30 minutes. After the reaction is complete, transfer the contents to a stainless steel plate.
Grind the solid to be solidified by cooling and add 100g of acetone.
was dissolved, further 5 g of sodium carbonate was added, stirring was continued for 5 hours to neutralize the para-toluenesulfonic acid used as a catalyst, and the neutralized salt and excess sodium carbonate were then removed by filtration. Acetone was removed from the neutralized acetone solution under reduced pressure using a rotary evaporator to obtain 45 g of a black solid resin. The softening point of this resin was 75°C. In addition, this resin was analyzed by high-performance liquid chromatography using four columns with an exclusion limit of 5000 (column material: GELKO A-120, Hitachi Chemical Co., Ltd. product name) connected in series and using tetrahydrofuran as the eluent. , using a standard polystyrene calibration curve,
When the weight average molecular weight was determined, it was a polymer with a weight average molecular weight of 770. Furthermore, when we performed NMR analysis and compared the raw material 4-cyclopentenyl phenol and the produced resin, we found that 4-cyclopentenyl phenol had a δ value of
A double bond proton of the cyclopentene ring was present at 5.7 ppm, but it was found that this double bond proton disappeared in the resulting resin and was used for polymerization. In addition, when the amount of benzene ring protons and the amount of alkyl group protons were compared, as shown in Table 2, the double bond of the cyclopentenyl group was alkylated to the o-position of another cyclopentenyl phenol, resulting in a polymer. It was found that the following was obtained.

[Table] Synthesis Example 2 o-cyclopentenylphenol and p-cyclopentenylphenol each 15.5% by weight
and 50 g of mixed cyclopentenyl phenol present at 84.5% by weight were placed in exactly the same flask as in Example 1, and 0.5 g of para-toluenesulfonic acid was added.
was added and reacted at 150°C for 5 hours. After the reaction, neutralization and desolubization were carried out in the same manner as in Example 1 to obtain 46 g of a black and colored resin. The softening point of this resin was 85°C. In addition, a column with an exclusion limit of 5000 (calum agent: GELKO A-120,
When two bottles of Hitachi Chemical Co., Ltd. (trade name) were connected in series and analyzed by high performance liquid chromatography using tetrahydrofuran as the eluent, the molecular weight
The polymer had a weight average molecular weight of 1100, with some molecules exceeding 5000. The results of NMR analysis of this polymer show that the raw material
A peak with a δ value of 5.8 ppm detected by NMR analysis (the peak of the double bond proton of the cyclopentenyl group)
has disappeared, indicating that it was used for polymerization. From the above, it can be seen that o-cyclopentenylphenol reacts in the same manner as p-cyclopentenylphenol to produce a polymer. Next, examples of the present invention will be shown. Example 1 160 parts of the cyclopentenylphenol polymer obtained in Synthesis Example 1, 16.2 parts by weight of formalin, 70 parts by weight of toluene, and 0.3 parts by weight of para-toluenesulfonic acid were placed in a three-necked flask equipped with a thermometer and a stirrer. The mixture was charged and reacted for 2 hours at 110-120°C. after that,
0.3 parts by weight of sodium carbonate was added and stirring was continued for 5 hours to neutralize the para-toluenesulfonic acid used as a catalyst, and then the neutralized salt and excess sodium carbonate were removed by filtration. After this, the toluene solution was heated to 150°C.
Desolubilized under reduced pressure for a period of time, the reaction product becomes black and colored [A]
(cyclopentenylphenol resin) was obtained.
The softening point of this reaction product [A] was 115°C. Furthermore, the polymer was analyzed by high performance liquid chromatography using four columns connected in series with an exclusion limit of 5000, and the weight average molecular weight was determined using a standard polystyrene calibration curve, and it was found to be a polymer of 2200. Next, reactant [A]
As a result of nuclear magnetic resonance analysis, the reactant [A] showed a new absorption at a δ value of 3.8 ppm. This indicates a proton generated by a methylene bond, indicating that the methylene bond is involved in the polymerization reaction. Example 2 A black and colored reaction product [B] was obtained using 160 parts by weight of the cyclopentenylphenol polymer obtained in Synthesis Example 2, but in the same manner as in Example 1, except that 160 parts by weight of the cyclopentenylphenol polymer obtained in Synthesis Example 2 was used. The softening point of this reaction product [B] was 135°C. Furthermore, when the weight nonuniformity molecular weight was determined using high performance liquid chromatography, it was found to be a polymer of 4500. Application example (tire rubber reinforcing material) Reactant [A] obtained in Example 1 or Synthesis Example 1
Cyclopentenylphenol polymer obtained in
100 parts of masticated natural rubber, 50 parts of carbon black, 5 parts of zinc oxide, 2 parts of stearic acid
1 part and 5 parts of spindle oil at 70°C for 5 minutes, then 2.5 parts of sulfur, 1 part of thiazole vulcanization accelerator, and 1 part of hexamethylene diamine were added and kneaded with rolls for 10 minutes at 70°C to obtain a mixed dough. And so. This kneaded dough was press-vulcanized at 140° C., 10 kg, and 30 minutes to obtain a rubber sheet. Table 3 shows the physical properties of this rubber sheet.

[Table] According to Table 3, the reaction product [A] obtained in Example 1
It has been shown that the use of cyclopentenylphenol-based polymers improves the hardness, strength and elongation of rubber in tensile tests compared to cyclopentenylphenol-based polymers. (Effects of the Invention) According to the present invention, a novel aldehyde reaction product useful for rubber reinforcing agents and the like can be obtained.

Claims (1)

[Claims] 1. General formula [] (wherein, R is hydrogen, halogen, nitro group, alkyl group having 1 to 5 carbon atoms, or alkoxy group, and m and n are each 1 or 2). Among these, compounds in which m+n is 3 or less and hydrogen is bonded to at least two of the two o-positions and p-positions with respect to the OH group (hereinafter referred to as polyfunctional cyclopentenyl phenol compounds) or the polyfunctional cyclopentenylphenol compounds. Among the functional cyclopentenyl phenol compounds and the cyclopentenyl phenol compounds represented by the above general formula [], m+n is 2 to 4 and hydrogen is present at only one of the two o-positions and p-positions with respect to the OH group. is bonded to the other substituents (hereinafter referred to as a monofunctional cyclopentenylphenol compound) by an alkyl addition reaction. Characteristic method for producing cyclopentenylphenol resin. 2. The cyclopentenyl phenol polymer contains a monofunctional cyclopentenyl phenol compound and a polyfunctional cyclopentenyl phenol compound in a ratio of 1/5 to 0/1 (molar ratio) of the former/latter. A method for producing a cyclopentenylphenol resin according to claim 1. 3. A cyclopentenylphenol polymer and an aldehyde are reacted by blending 0.15 to 2 moles of the aldehyde per mole of the polyfunctional cyclopentenylphenol compound component in the polymer, or 2. A method for producing a cyclopentenylphenol resin according to item 2.