JPH09249714A - Production of maleinized polybutene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a maleinized polybutene which forms less sludge per reaction run and undergoes less discoloration. SOLUTION: A process for producing a maleinized polybutene by reacting polybutene with maleic anhydride, wherein 100 pts.wt. polybutene is reacted with 10-50 pts.wt. maleic anhydride in the presence of 0.2-10 pts.wt. silica/ alumina at 150-250 deg.C.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to the production of maleated polybutene used as a raw material for epoxy resin curing agents or polyester resins, alkyd resins, plasticizers, paper sizing agents, fuel additives, lubricating oils, surfactants and the like. Regarding the method.

[0002]

2. Description of the Related Art As a method for producing maleated polybutene, it has been necessary to react polybutene with maleic anhydride at a high temperature for a long time. However, since the reactivity of polybutene and maleic anhydride is low in these methods, higher temperature and longer reaction time are required, but maleic anhydride is partially decomposed in the reaction on the high temperature side, which further polymerizes black There was a problem of generating tar-like substances (sludge). A portion of this sludge disperses in the reaction product and another portion adheres to the reactor wall. Since the reaction between polybutene and maleic anhydride is very slow and is usually carried out in a batch system, the deposition of sludge on the reactor wall and the stirrer increases as the number of reactions increases. Therefore, not only the thermal conductivity of the reactor is lowered, the stirring efficiency is lowered, the reaction rate is lowered, and also the pressure of the reactor is increased to cause a danger. For this reason, it is necessary to remove the sludge adhering to the inner surface after several times of reaction, which reduces productivity and causes problems such as treatment of the removed sludge. Further, since a part of the sludge is mixed in the reaction product, there is a problem that the product is colored.

Several methods have been disclosed so far in order to reduce these sludges. For example, a method of using chlorinated polybutene in place of polybutene is disclosed in U.S. Pat.No. 3,957,855 and U.S. Pat. A method of introducing is disclosed. Further, U.S. Pat.No. 3,935,249 discloses a method in which a trace amount of an inorganic chlorinated compound is present in the system to carry out a reaction, and U.S. Pat.No. 3,960,900 describes a trace amount of a halogenated hydrocarbon. A method of reacting by allowing it to exist in the system is disclosed. These methods are carried out in the presence of chlorine or halogen compounds in the system, and there remains a problem that trace amounts of chlorine or halides cannot be avoided in the maleated polybutene obtained.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing maleated polybutene which produces less sludge during the reaction and is less colored.

[0005]

The present inventors have arrived at the present invention as a result of intensive research to solve the above-mentioned problems. That is, the present invention is a method for producing a maleinized polybutene by reacting polybutene with maleic anhydride, wherein 10 to 50 parts by weight of maleic anhydride is added to 0.2 to 10 parts by weight of silica based on 100 parts by weight of polybutene. A method for producing a maleated polybutene, which comprises reacting at 150 to 250 ° C. in the presence of alumina.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The polybutene used in the present invention is, for example, a polymer of isobutylene such as diisobutylene, as long as it has an unsaturated residue in the polymer, and industrially as polybutene. It may be a mixture of polymers such as 1-butene and 2-butene other than the produced isobutylene. The number average molecular weight of polybutene is preferably 100 to 3,000. The amount of maleic anhydride used in the present invention is 10 to 50 parts by weight, preferably 1 to 100 parts by weight of polybutene.
5 to 30 parts by weight. When this addition amount is less than 10 parts by weight, the maleinization ratio of the maleated polybutene obtained is low and it becomes impossible to impart polarity to the nonpolar polybutene. Further, if the addition amount is more than 50 parts by weight, maleation of the obtained resin is increased,
In this case, not only maleated polybutene but also maleic anhydride remaining as an unreacted product increases, which causes disadvantages such as difficulty in post-treatment such as separation and recovery, which is not suitable.

As the silica-alumina used in the present invention, commercially available silica-alumina can be used. You may use what was synthesize | combined by the method. The composition ratio of silica and alumina is not particularly limited, but from the viewpoint of easy synthesis, the ratio of alumina is preferably 5 to 30 wt%. The amount of silica-alumina used is in the range of 0.2 to 10 parts by weight based on 100 parts by weight of polybutene. Particularly preferably, it is in the range of 0.5 to 5 parts by weight. If the amount used is less than 0.2 parts by weight, the catalytic effect due to the addition of silica-alumina will not be sufficient and the reaction will not proceed sufficiently. On the other hand, if the amount is more than 10 parts by weight, it is economically disadvantageous, which is not preferable. In general, it is known that silica alumina is activated by firing to increase the acid strength, but in the present invention, the fired one is preferably used, and the firing conditions are 300 ° C. or higher and 800 ° C.
It is preferably less than about 3 to 5 hours. The heating reaction used in the present invention has a temperature in the range of 150 ° C to 250 ° C.
If the reaction temperature is lower than 150 ° C., the addition reaction of maleic anhydride does not proceed, so polybutene and maleic anhydride exist as unreacted products, and the product yield decreases, which is not suitable. On the other hand, if the temperature is higher than 250 ° C., depolymerization of polybutene is promoted and the yield of the maleated polybutene obtained is lowered, which is not preferable. The reaction pressure and the reaction time are not particularly limited, but for example, atmospheric pressure to 30 kg / cm ² and the reaction time are preferably 0.5 to 24 hours. Further, the order of charging polybutene, maleic anhydride and silica-alumina may be either. Further, they may be charged all at once or maleic anhydride may be added dropwise.

[0008]

INDUSTRIAL APPLICABILITY The present invention has a reaction temperature of 250 ° C. or lower, which is lower than that of the conventional method. Therefore, sludge is less generated and coloring is less. Therefore, the present invention cannot be used due to the blackish brown coloring of maleated polybutene. Can also be used. In addition, since sludge generated as a by-product during the reaction is small and it does not adhere to the reactor wall, it is possible to operate the plant with high productivity.

[0009]

EXAMPLES Next, the present invention will be specifically illustrated by examples. Example 1 After charging 500 g of polybutene (trade name PB-10N, manufactured by NOF CORPORATION, number average molecular weight 1000) into a 1 liter autoclave equipped with a thermometer and a stirrer, 98 g of maleic anhydride and silica alumina (trade name) , SA-LA Catalysis Chemical Co., Ltd.) 10 g in a batch, and after thoroughly substituting with nitrogen, 2
The reaction was carried out at 00 ° C for 8 hours. After the reaction, the reaction solution was cooled to 80 ° C., diluted with toluene and filtered. No sludge adhered to the reactor wall. Almost all the sludge of the reaction solution was adsorbed by the charged silica-alumina. The adsorbed sludge was obtained by concentrating an acetone solution obtained by washing silica alumina with acetone. The amount of sludge obtained was 1 wt% of the charged amount. The solvent was removed from the filtered reaction solution by distillation under reduced pressure at 100 ° C. and 15 to 5 mmHg, and then unreacted maleic anhydride was removed at 3 mmHg and 150 ° C. for 3 hours to obtain maleated polybutene having an acid value of 105. The acid value, maleation rate, and amount of unreacted polybutene were measured by the following measuring methods.

<Method of measuring acid value> The acid value of the maleated polybutene obtained was in accordance with the following method. Approximately 3 mg (decimal point 4th) of maleated polybutene in a 200 ml Erlenmeyer flask.
Accurately weigh up to the digit) Charge, tetrahydrofuran 25m
1 was added to dissolve maleated polybutene, 5 ml of distilled water was added, and the mixture was stirred for 1 minute and allowed to stand for 1 minute. Next, add 2 to 3 drops of 1% phenolphthalein indicator solution and perform titration with 1 / 10N potassium hydroxide ethanol solution. After the titration is completed, perform until the solution remains a light red color for about 1 minute. The end point was the amount. Similarly, it was carried out without charging maleated polybutene as a blank. The acid value was calculated according to the following formula. Acid value of maleated polybutene (mgKOH / g) =
((Titrate-Blank titer) x 56.1 x 0.1) /
Charged amount of maleated polybutene (g)

<Measurement Ratio of Malein and Unreacted Polybutene> The maleation ratio of maleated polybutene was measured according to the following procedure. A sample of 5 g of a reaction product of maleic anhydride and polybutene was dissolved in THF, and silica gel (Wakogel C-200, manufactured by Wako Pure Chemical Industries, Ltd.) 50
g column and dissolved with 1 liter of hexane.
Hexane was removed from the solution with an evaporator, and the residue was weighed to calculate more unreacted polybutene and maleation rate according to the following equation. Unreacted polybutene (wt%) = true weight of residue / sample weight × 100 Maleation rate (wt%) = 100−unreacted polybutene The results are shown in Table 1.

[0012]

[Table 1]

Examples 2 to 5 Example 1 was conducted under the conditions shown in Table 1 except that the charged molar ratio of polybutene and maleic anhydride and the reaction conditions of silica alumina were changed.
The same operation was performed. The reaction conditions and results are shown in Table 1.

Comparative Example 1 Example 1 under the conditions shown in Table 1 except that silica alumina was not used.
The same operation was performed. The reaction conditions and results are also shown in Table 1.

Comparative Example 2 Table 1 except that alumina was used instead of silica alumina.
The same operation as in Example 1 was carried out under the above conditions. The reaction conditions and results are also shown in Table 1.

Claims (1)

[Claims] 1. A method for producing a maleinized polybutene by reacting polybutene with maleic anhydride, wherein 10 to 50 parts by weight of maleic anhydride is added to 0.2 to 10 parts by weight of silica based on 100 parts by weight of polybutene. A method for producing maleated polybutene, which comprises reacting at 150 to 250 ° C. in the presence of alumina.