JPH0689092B2 - Process for producing phenolic resin modified with heavy petroleum oils or pitches - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a phenol resin modified with heavy petroleum oils or pitches.

(Prior Art) Phenolic resin has excellent mechanical properties and has been widely used since ancient times, but its light resistance and alkali resistance are rather low, and it is easy to change dimensions and electric resistance by absorbing water or alcohol. However, there is a problem that heat resistance, especially oxidation resistance at high temperature, is slightly low.

Various modifications have been investigated to solve such problems. In particular, in order to impart resistance to changes due to light, chemicals, oxidation, etc., modification with fats and oils, rosins or neutral aromatic compounds has been of interest.

Huang Keiun et al. Studied the reaction of m-xylene-formaldehyde resin with novolak and showed that m-xylene-formaldehyde resin can be used as a curing agent for novolak.

In addition, even if m-xylene and formaldehyde are reacted and then low molecular weight phenols are added and reacted,
It is not completely insolubilized, and it is also shown that phenols have a small ability as a curing agent [Industrial Chemistry Magazine, Volume 60,
1579 (1957)].

Further, Japanese Patent Publication No. 53-5705 discloses a dry oil-modified phenol obtained by modifying a mesitylene resin obtained by reacting an alkylbenzene containing mesitylene as a main component with formaldehyde with a drying oil and phenols and further resolizing the resin. Resins are disclosed. During the production of this resin, the catalyst used in the first half of the reaction is an acid, and the catalyst used in the second half of the reaction is a base, so the catalysts in the first and second half of the reaction cannot coexist. It is necessary to divide into two or more steps. Further, there is a problem that the basic catalyst is consumed for neutralizing the acid, which is disadvantageous in cost.

Further, JP-A-61-235413 discloses an aromatic hydrocarbon-
When a formaldehyde resin and phenol are reacted to produce a phenol-modified aromatic hydrocarbon resin, the aromatic hydrocarbon-formaldehyde resin has a diallylmethane content of 5% by weight or less and a xylenol value of 15 mol / kg.
It is disclosed that a thermosetting resin having excellent heat resistance can be obtained by using the above-mentioned highly reactive one. Although this resin has a light intrinsic color and exhibits excellent properties, it has the drawback of slow curing and requiring high temperature and long time.

Each of these methods is a multi-step production method, including first a step of producing an aromatic hydrocarbon-formaldehyde resin, and a step of reacting an aromatic hydrocarbon-formaldehyde resin of the next stage with a phenol, Manufacturing process,
Especially, there is a problem that the control system is complicated and the equipment cost and eventually the manufacturing cost are increased.

Further, JP-B-60-36209 discloses that one or more polycyclic aromatic hydrocarbons selected from the group consisting of acenaphthene, acenaphthylene and derivatives thereof,
Disclosed is a method in which phenols and formaldehyde are mixed and heated and reacted in a one-step process in the presence of an acid catalyst. This method has an advantage that a modified phenolic resin having excellent properties can be obtained because a compound having high reactivity with formaldehyde is selectively used among polycyclic aromatic hydrocarbons. There is no thermal decomposition product containing a large amount of these compounds, and it is necessary to synthesize these compounds for mass production, and there is a drawback that the cost becomes high.

(Problems to be Solved by the Invention) The present invention is a drawback of a phenolic resin modified with fats, oils, rosins or neutral aromatic hydrocarbons, which is a complicated manufacturing process and often requires multiple steps. The object of the present invention is to solve the problem that the raw material cost and the cost required for curing are high, because many of them have low reactivity and it is difficult for them to be thermally cured unless a special raw material is used.

Further, the present invention aims to provide a novel modified phenolic resin excellent in heat resistance, oxidation resistance and mechanical strength which cannot be obtained by a conventional phenolic resin, by developing such a special production method. .

(Means for Solving the Problems) The present invention is: aromatic hydrocarbon fraction fa value is 0.4 to 0.95, aromatic ring hydrogen amount H
Heavy petroleum oils or pitches with a value of 20-80% 1
Formaldehyde polymer is mixed in such a manner that the number of moles in terms of formaldehyde becomes 1 to 10, and the phenols are mixed with the petroleum heavy oils or pitches while heating and stirring in the presence of an acid catalyst. And the number of moles of phenols to be added at an addition rate of 0.05 to 5% by weight / min with respect to the total weight of the formaldehyde polymer, and at that time to 1 mole of the petroleum heavy oil or pitches. Is from 0.3 to 5 and polycondensed to produce a phenol resin modified with heavy petroleum heavy oil or pitches.

Further, in the method for producing a phenol resin modified with heavy petroleum oils or pitches, the reaction time of formaldehyde estimated from the amount of remaining free formaldehyde is 70% or less when the phenols are added.

In the method of the present invention, the aromatic hydrocarbon fraction fa value and the aromatic ring hydrogen content Ha value are shown in the following equations.

The fa value can be determined by ¹³ C-NMR.
The Ha value can be obtained by ¹ H-NMR.

In the present invention, the raw material petroleum heavy oils or pitches
When the fa value is small, the aromatic content is small, so that the modification effect of the performance of the modified phenol resin obtained, particularly the modification effect of heat resistance and oxidation resistance tends to be small. In particular, when the fa value is 0.4 or less, this modifying effect becomes extremely small, which is not preferable.

Further, in the case of heavy petroleum oils or pitches having an fa value of more than 0.95, the reactivity between aromatic ring hydrogen and formaldehyde decreases, which is not preferable.

Therefore, in the present invention, the fa value is preferably 0.4 to 0.95, and more preferably 0.5 to 0.8.

In the present invention, when the Ha value of the petroleum heavy oil or pitches as the raw material becomes small, the aromatic ring hydrogen content that reacts with formaldehyde becomes small, and the reactivity becomes poor, so that the effect of modifying the performance of the phenol resin is improved. It is not preferable because it becomes scarce. It is considered that 20% or more has a practical Ha value.

As the Ha value increases, the reactivity of the aromatic ring hydrogen component tends to gradually decrease. If a heavy petroleum oil or pitch having a Ha value of more than 80% is used as a raw material, the strength of the modified phenol resin tends to decrease, which is not preferable. In the present invention, the Ha value is desirably 20 to 80%, preferably 25 to 60%.

In the heavy petroleum oil or pitches used in the present invention, the number of condensed rings is not particularly limited, but is preferably a condensed polycyclic aromatic hydrocarbon mainly having 2 to 4 rings. In the case of a condensed polycyclic aromatic hydrocarbon having 5 or more rings, the boiling point exceeds 450 ° C. in most cases, so that it is difficult to collect those having a narrow boiling range, and there is a problem that the quality is not stable. Further, in the case of mainly monocyclic aromatic hydrocarbons, there is a problem that the effect of modifying the performance of the phenol resin is small because the reactivity with formaldehyde is low.

The petroleum heavy oils or pitches that are the raw materials of the modified phenol resin of the present invention are crude oil distillation residual oil, hydrogenolysis residual oil,
It is obtained as a catalytically cracked residual oil and a vacuum distillate or a heat-treated product of these residual oils. Of these, those having appropriate fa values and Ha values are selected and used.

Formaldehyde polymer used in the present invention,
Linear polymers such as paraformaldehyde, polyoxymethylene (particularly oligomers) and cyclic polymers such as trioxane.

The mixing ratio of the petroleum-based heavy oils or pitches to the formaldehyde polymer is the number of moles of the formaldehyde-converted formaldehyde polymer based on the average number of moles of 1 mol calculated from the average molecular weight of the petroleum-based heavy oils or pitches. , 1 to 10. When the mixing ratio is 1 or less, the strength of the obtained modified phenolic resin cured product is low, which is not preferable. On the other hand, when it is 10 or more, the performance and yield of the obtained cured product hardly change, so it is considered useless to use more formaldehyde polymer. The mixing ratio of the heavy petroleum oil or pitches to the formaldehyde polymer in the present invention is preferably 2
~ 7.

As the acid catalyst in the present invention, a Bronsted acid or a Lewis acid can be used, but a Bronsted acid is preferably used. As the Bronsted acid, toluene sulfonic acid, xylene sulfonic acid, hydrochloric acid, sulfuric acid, formic acid and the like can be used, but p-toluene sulfonic acid and hydrochloric acid are particularly excellent.

The amount of the acid catalyst used is 0.1 to 30% by weight, preferably 1 to 10% by weight, based on the total amount of heavy petroleum oils or pitches, formaldehyde polymer and phenols.
When the amount of the acid catalyst used is small, the reaction time tends to be long, and the reaction tends to be insufficient unless the reaction temperature is raised. On the other hand, even if the amount of the acid catalyst used is large, the reaction rate may not be high, and the cost may be disadvantageous. In addition, it may be necessary to recover the acid catalyst or neutralize it, which may result in extra cost.

The phenols used in the present invention are preferably one or more phenolic compounds selected from the group consisting of phenol, cresol, xylenol and resorcin.

In the present invention, the phenols are added little by little by a method such as dropping and mixing. The rate of addition is from 0.05 to 5% by weight / minute, preferably from 0.1 to 2% by weight, based on the total weight of the reaction mixture. Addition rate is 0.0
If the amount is 5% by weight or less, the time required for addition is too long and the cost is increased, which is not preferable. On the other hand, when the addition rate is 5% by weight / min or more, the added phenols react rapidly with free formaldehyde,
It is not preferable because it is difficult to form a uniform mixture or cocondensate.

The cause of such non-uniformity is that phenols have a significantly higher reactivity to formaldehyde than petroleum heavy oils or pitches, and it is necessary to keep the initial concentration of phenols low. It can be presumed that this is because formaldehyde selectively reacts with the phenols or the condensate of formaldehyde and phenol formed by the reaction, and becomes insoluble in the system. Alternatively, formaldehyde is first consumed in the reaction between the phenols or the phenols produced by the reaction and the condensate of formaldehyde, and the petroleum heavy oils or pitches or the petroleum heavy oils produced by the reaction are consumed. It is presumed that the condensate of pitches and formaldehyde cannot further react with formaldehyde and is separated from the reaction system.

In the present invention, when to start adding phenols,
Although not particularly limited, phenols are added at the time when the reaction rate of formaldehyde estimated from the amount of residual free formaldehyde is 70% or less, preferably 50% or less. The addition start time may be a time when the reaction between the heavy petroleum oil or pitches and formaldehyde has not substantially progressed. If the reaction rate of formaldehyde is 70% or more, the amount of formaldehyde that reacts with phenols will decrease, so the performance of the resin produced will decrease significantly, and in extreme cases, a hardened product cannot be obtained unless a curing agent is added. It is not preferable.

The amount of phenols added is 0.3 to 5 as the number of moles of phenols per 1 mole of the average number of moles calculated from the average molecular weight of heavy petroleum oils or pitches. When the amount added is 0.3 or less, the reactivity of petroleum heavy oils or pitches with formaldehyde is inferior to the reactivity of phenols with formaldehyde, so a sufficient crosslink density cannot be reached and curing There is a problem that the strength of the body is lower than that of general phenolic resin. In particular, it has a low impact resistance and exhibits a brittle defect. On the other hand, the amount of phenols added is 5
In the above cases, the modifying effect by modifying the phenolic resin is small, which is not preferable. The amount of phenols added in the present invention is preferably 0.5 to 3.

The reaction temperature is 50 to 160 ° C, preferably 60 to 120 ° C.
The reaction temperature is determined in consideration of the raw material composition, the reaction time, the properties of the resin produced, and the like.

The reaction time is 0.5 to 10 hours, preferably 1 to 5 hours. The reaction time is determined in consideration of the raw material composition, the reaction temperature, the addition rate of phenols, the properties of the resin produced, and the like.

In the present invention, when the reaction is carried out batchwise, it can be carried out in one step, and one step is preferable. In addition, when the continuous method is used, it is not necessary to use a device that is difficult to control, such as continuously mixing two or more kinds of reaction products, which are used in the conventional modified phenol resin, in a fixed amount, and the intermediate portion is used. A reaction vessel of a complete mixing type may be placed, and the phenols to be added may be fed into the reaction vessel in fixed amounts. Such a device is relatively inexpensive and has good operability.

In the present invention, a solvent can be used in the reaction. The reaction can be performed without a solvent, but in that case, it is necessary to pay attention to the uniformity of the reaction. The use of a solvent reduces the viscosity of the reaction system and improves the homogeneity of the reaction.
However, it was necessary to remove the solvent before curing,
Except for special ones, the cost is generally high.

Solvents include halogenated aromatic hydrocarbons such as chlorobenzene, nitrated aromatic hydrocarbons such as nitrobenzene, nitrated aliphatic hydrocarbons such as nitroethane and nitropropane, perchlorene, trichlene and carbon tetrachloride. Halogenated aliphatic hydrocarbon and the like can be used.

Since the modified phenolic resin produced by the method of the present invention is thermosetting, it can be easily made into a thermosetting body by heating as it is.

Further, the modified phenolic resin produced by the method of the present invention,
As such, it can be used as a binder for carbon moldings and the like.

(Function) In the present invention, the phenol resin is further improved in heat resistance and chemical resistance because it is modified with a condensed polycyclic aromatic hydrocarbon such as heavy petroleum oils or pitches.

Aromatic hydrocarbons used in the present invention, such as heavy petroleum oils, pitches, etc., have extremely different reactivity to formaldehyde compared to phenols, and therefore, the reaction can be carried out from the beginning of the reaction by three factors. When mixed and placed, the modified phenolic resin cannot be obtained because only the phenolic resin is mainly produced and the aromatic hydrocarbons are mostly phase-separated without being reacted. Therefore, conventionally, a two-step operation of previously reacting an aromatic hydrocarbon with formaldehyde to prepare an aromatic hydrocarbon-formaldehyde resin, and appropriately mixing this with phenols to obtain a modified phenol resin Was needed.

In practice, 2 sets or 3
A set of reaction equipment is required, the equipment is expensive, and it is difficult to operate.

In the present invention, in producing a modified phenolic resin,
First, to a mixture of petroleum heavy oil or pitch and formaldehyde, phenols are added little by little while heating and stirring in the presence of an acid catalyst to react with formaldehyde, and at the same time, a heavy petroleum oil produced. Alternatively, a uniform reaction mixture can be obtained by reacting the phenol with the condensate of pitches and formaldehyde. In the case of the batch method, the reaction can be carried out in a single step, and even in the case of the continuous method, the production can be carried out with simple equipment, and a certain range of conditions are found.

(Examples) Hereinafter, examples of the present invention will be described in more detail and specifically, but these do not limit the present invention.

The properties of the reaction raw materials used in the examples are shown in Table 1. The feedstock and pitch are obtained by distilling the bottom oil obtained by fluid catalytic cracking (FCC) of vacuum gas oil.

Example 1 200 g (0.74 mol) of the feedstock oil shown in Table 1, 90 g of paraformaldehyde (number of moles converted to formaldehyde, 3.0 mol, the same applies hereinafter), p-toluenesulfonic acid (monohydrate) 17.8 g
Was charged into a glass reactor and the temperature was raised to 80 ° C. with stirring. After reacting at 80 ℃ for 15 minutes, phenol 66
g (0.70mol) 1cc / min (0.34% based on the total weight of petroleum heavy oil or pitches and formaldehyde polymer)
The reaction was continued for 60 minutes while the solution was added dropwise at a dropping rate of 1 / min. After completion of the dropping of phenol, stirring was continued for another 2 hours for reaction. After the reaction is completed, the reaction product is taken out,
Upon cooling, 364 g of modified phenol resin was obtained.

The softening point of the resulting modified phenolic resin was measured with a flow tester (CFT-20 manufactured by Shimadzu Corporation), and it was 42 ° C. When this modified phenol resin was treated at 200 ° C. for 20 minutes, a thermosetting body was obtained.

Also, put this modified phenolic resin in the mold and
When kept at 200 ° C for 1 hour under pressure of g / cm ² · G,
A dense compact was obtained and the oxidation resistance was also good.

Example 2 300 g (1.1 mol) of the raw material oil in Table 1, paraformaldehyde
180g (6.0mol), p-toluenesulfonic acid (monohydrate)
A glass reactor was charged with 30.6 g and 165 g of chlorobenzene, and the temperature was raised to 80 ° C. with stirring. After reacting at 80 ° C. for 20 minutes, 130 g (1.4 mol) of phenol was added dropwise at a dropping rate of 2 cc / min (0.42% / min) and reacted for 60 minutes. After completion of the dropping, stirring was continued for another 20 minutes for reaction. After completion of the reaction, the reaction mixture was poured into 1700 g of n-hexane to precipitate the modified phenol resin. The precipitate was filtered and washed, and then dried under reduced pressure at 25 ° C to obtain 500 g of modified phenol resin.

The softening point of the resulting modified phenolic resin was measured by a flow tester and found to be 99 ° C. When this modified phenol resin was treated at 200 ° C. for 10 minutes, a thermosetting body was obtained.

In addition, put the modified phenolic resin in the mold, 400kg / cm
^When kept at 200 ° C. for 30 minutes under a pressure of ² · G, a dense molded body was obtained.

Example 3 150 g (0.55 mol) of the stock oil shown in Table 1, 100 g (3.3 mol) of paraformaldehyde, 23.3 g of hydrochloric acid and 110 g of chlorobenzene were charged into a glass reactor and heated to 90 ° C. with stirring. When the temperature reached 90 ° C, add 60 g (0.64 mol) of phenol.
The solution was added dropwise at a dropping rate of 1 cc / min (0.40% / min), and after completion of the dropping of phenol, the mixture was further stirred for 15 minutes to cause a reaction. After completion of the reaction, the reaction mixture was poured into 880 g of n-hexane to precipitate the modified phenol resin. Filter the precipitate
After washing, dry under reduced pressure at 25 ℃ and denatured phenol resin 175g
Got

The softening point of the resulting modified phenolic resin was measured with a flow tester and found to be 92 ° C. When this modified phenol resin was treated at 250 ° C. for 20 minutes, a thermosetting body was obtained.

Also, put this modified phenolic resin in the mold and
When kept at 250 ° C for 1 hour under a pressure of g / cm ² · G,
A dense compact was obtained.

Example 4 150 g (0.55 mol) of the raw material oil shown in Table 1, 90 g (3.0 mol) of paraformaldehyde, 15.3 g of p-toluenesulfonic acid (monohydrate) and 83 g of chlorobenzene were charged into a glass reactor and stirred. While raising the temperature to 95 ° C. When the temperature reached 95 ° C, 65 g (0.60 mol) of p-cresol was added at 1 cc / min (0.42% /
The reaction was carried out for 60 minutes while adding dropwise at a dropping rate of (minutes). After completion of dropping of p-cresol, the mixture was further stirred for 1 hour for reaction. After completion of the reaction, the reaction mixture was poured into 880 g of n-hexane to precipitate the modified phenol resin. After filtering and washing the precipitate, it is dried under reduced pressure at 25 ° C and the modified phenolic resin 24
I got 1g.

When the softening point of the produced resin was measured by a flow tester, it was 69 ° C. This modified phenolic resin at 200 ℃ 2
When treated for 0 minutes, a thermosetting body was obtained.

Also, put this modified phenolic resin in the mold and
When kept at 200 ° C for 1 hour under pressure of g / cm ² · G,
A dense compact was obtained.

Example 5 A glass reactor was charged with 186 g (0.50 mol) of the pitch obtained in Table 1, 60 g (2.0 mol) of paraformaldehyde, 13.9 g of p-toluenesulfonic acid (monohydrate) and 110 g of chlorobenzene, The temperature was raised to 70 ° C with stirring. When the temperature reached 70 ° C., 32.5 g (0.35 mol) of phenol was added dropwise at a dropping rate of 1 cc / min (0.41% / min). After completion of dropping phenol, the mixture was stirred for 15 minutes for reaction. After completion of the reaction, the reaction mixture was poured into 1020 g of n-hexane to precipitate the modified phenol resin. The precipitate was filtered and washed, and dried under reduced pressure at 25 ° C to obtain 243 g of modified phenol resin.

The softening point of the resulting modified phenolic resin was measured by a flow tester and found to be 132 ° C. When this modified phenol resin was treated at 200 ° C. for 20 minutes, a thermosetting body was obtained.

Also, put this modified phenolic resin in the mold and
When kept at 200 ° C for 1 hour under pressure of g / cm ² · G,
A dense compact was obtained.

Example 6 225 g (0.83 mol) of the raw material oil obtained in Table 1 and 60 g of trioxane (formaldehyde conversion mole number, 2.0 mol) were charged into a glass reactor and heated to 60 ° C. with stirring.
When the temperature reached 60 ° C, 17.8 g of p-toluenesulfonic acid (monohydrate) was added, and the temperature was raised to 95 ° C with further stirring. When the temperature reached 95 ° C, add 40 g (0.42 mol) of phenol.
Dropping was performed at a dropping rate of 1 cc / min (0.35% / min). After completion of the dropping of phenol, the reaction product was taken out from the reaction vessel and cooled to obtain 331 g of modified phenol resin.

When the softening point of the produced resin was measured by a flow tester, it was 69 ° C. This modified phenolic resin is 200
When it was treated at ℃ for 15 minutes, a thermosetting body was obtained.

Also, put this modified phenolic resin in the mold and
When kept at 200 ° C for 1 hour under pressure of g / cm ² · G,
A dense compact was obtained.

(Effects of the Invention) The cured molded article from the modified phenolic resin obtained by the method of the present invention does not undergo substantial alteration even when heated at 300 ° C. for several hours in an inert atmosphere and in air.

The mechanical strength is almost the same as that of the conventional phenol resin.

Compared with that of conventional phenolic resin, the glass transition point is
It is several tens of degrees Celsius to 100 degrees Celsius higher, and is superior in heat resistance to conventional phenolic resins.

Shows excellent performance as an electrical insulating material for printed wiring boards, etc., with little deterioration of electrical properties at high temperatures.

The modified phenolic resin obtained by the method of the present invention has excellent light resistance and can be used as a base resin for black paint.

It has excellent heat resistance and is excellent as a matrix resin for composite materials using carbon fiber or the like as a reinforcing material.

Further, it has a high rate of carbonization and residue when heated at a high temperature, and can be used as a binder for carbon molded products. In particular,
It can be used as a binder for forming carbon fiber and carbonized to be processed into carbon-carbon composite material.

Claims (4)

[Claims] 1. Formaldehyde polymer is added to 1 mol of petroleum heavy oil or pitch having an aromatic hydrocarbon fraction fa value of 0.40 to 0.95 and an aromatic ring hydrogen content Ha value of 20 to 80%. ,
Mixing so that the number of moles of formaldehyde is 1 to 10, while heating and stirring in the presence of an acid catalyst, phenols relative to the total weight of the petroleum heavy oils or pitches and the formaldehyde polymer. 0.05 to 5% by weight / minute, and the number of moles of phenols added to 1 mole of the petroleum heavy oil or pitch is 0.
A method for producing a phenol resin modified with heavy petroleum-based heavy oils or pitches, which is characterized by being polycondensed so as to be 3 to 5. 2. A petroleum-based heavy oil, characterized in that the petroleum-based heavy oil or pitch according to claim (1) is mainly a condensed polycyclic aromatic hydrocarbon having 2 to 4 rings, or A method for producing a phenol resin modified with pitches. 3. A heavy petroleum-based compound, wherein the phenols according to claim (1) is one or more phenolic compounds selected from the group consisting of phenol, cresol, xylenol, and resorcin. A method for producing a phenol resin modified with oils or pitches. 4. The petroleum heavy oil according to claim 1, wherein the reaction rate of formaldehyde estimated from the amount of residual free formaldehyde when the phenol is added is 70% or less. A method for producing a phenol resin modified with pitches.