JPH0617381B2 - Selective hydrolysis of copolymers of P-acetoxystyrene and dialkyl muconates or alkyl sorbates - Google Patents

Description

TECHNICAL FIELD The present invention relates to the technical field of vinylphenol copolymers.

PRIOR ART Homopolymers and copolymers of p-vinylphenol (also known as 4-hydroxystyrene) are known polymers that can be used in many applications, such as in the production of metal processing compositions and photoresists. Polymers of p-vinylphenol can be prepared by polymerizing p-vinylphenol itself. However, p-vinylphenol is an unstable compound and must be stored frozen to prevent its autopolymerization. Even under cryopreservation conditions, this monomer gradually polymerizes to a low molecular weight polymer. on the other hand,
4-acetoxystyrene (p-acetoxystyrene), which is an acetic acid ester of p-vinylphenol, is a stable monomer and can be easily homopolymerized or copolymerized with a low, medium or high degree of polymerization polymer. After the polymerization, the phenol ester group is hydrolyzed to produce a p-vinylphenol polymer.

Corson et al, Journal of Organic Chemistry, 23 , 544-5
49 (1958) describes a 5-step method for producing p-vinylphenol using phenol as a raw material. Phenol is first acetylated to p-hydroxyacetophenone, which is further acetylated to give p-acetoxyacetophenone. This compound is hydrogenated to p-acetoxyphenylmethylcarbinol, which is then dehydrated to give p-acetoxystyrene. This p
-Saponification of acetoxystyrene with potassium hydroxide gives p-vinylphenol. Packham, Jo
urnal of the Chemical Society, 1964 , 2617-2624,
Hydrolysis of crosslinked poly-4-hydroxystyrene,
A method is described in which the polymer is heated under reflux for 2 days in an alkaline aqueous solution of dioxane.
U.S. Pat. No. 4,544,704 discloses a method of hydrolyzing a copolymer of styrene and p-isopropenylphenylacetate with an aqueous sodium hydroxide solution in methanol and toluene using a small amount of benzyltrimethylammonium chloride as a phase transfer agent. Is disclosed. Arshady et al., Journal of Polymer Science, 12 , 2
017-2025 (1974) describes a method of obtaining a vinylphenol polymer by hydrolyzing a copolymer of styrene and acetoxystyrene using hydrated hydrazine in dioxane.

The transesterification reaction of poly (4-acetoxystyrene) in methanol using sodium methylate is described in US Pat. No. 2,276,138. In this U.S. patent, 4-acetoxystyrene monomer is treated with potassium hydroxide in methanol at room temperature or under heating,
Alternatively, it is also stated that a resinous polymer can be obtained by treating with methanol using sulfuric acid as a transesterification catalyst.

US Patent Application No. 22,186 filed on Mar. 5, 1987
Describes the hydrolysis of p-acetoxystyrene homopolymers and copolymers by acid catalyzed transesterification in alcohols to obtain p-vinylphenol homopolymers and copolymers.

US Patent Application No. 29,108 filed March 23, 1987
Describes a copolymer of p-acetoxystyrene and a dialkyl muconate.

[Problems to be Solved by the Invention] The present invention selectively hydrolyzes a copolymer of p-acetoxystyrene and dialkyl muconate or alkyl sorbate into a copolymer of p-vinylphenol and dialkyl muconate or alkyl sorbate. Regarding the method of disassembling.

In one aspect, the invention relates to an acid-catalyzed selective hydrolysis process. In another aspect, the invention relates to a base catalyzed selective hydrolysis process.

[Means for Solving the Problems] According to the method of the present invention, a copolymer of p-acetoxystyrene and a dialkyl muconate or an alkyl sorbate is slurried in a water or alcohol medium, and then an alkyl muconate ester of the copolymer is used. Hydrolysis of the acetoxy group alone in the presence of an acid or base without substantially saponifying the group or the alkyl sorbate group yields a copolymer of p-vinylphenol and dialkyl muconate or alkyl sorbate. The hydrolysis is preferably at a temperature of about 20-100 ° C. in the presence of an acid or base in the slurry for a time sufficient to hydrolyze the acetoxy groups of the copolymer to phenolic groups, which causes the copolymer to react with its alcohol. Alternatively, it is shown to dissolve in an aqueous medium). The resulting copolymer can be used as a vinylphenol copolymer without being hindered by the reaction with carboxylic acid groups because the muconic acid or sorbic acid ester groups are not hydrolyzed.

The dialkyl muconate used in the preparation of the raw material copolymer used in the present invention is a diester derivative of muconic acid.
Muconic acid is a diolefinically unsaturated derivative of adipic acid and is obtained by microbial oxidation of various hydrocarbon substrates, as described in US Pat. Nos. 4,480,034 and 4,535,059. The dialkyl muconate used in the present invention preferably has an alkyl group having about 1 to 4 carbon atoms, and can be produced by direct esterification of muconic acid with methanol, ethanol, propanols or butanols. Preferred dialkyl muconates useful in the present invention are:
Dimethyl muconate and diethyl muconate.

The alkyl sorbate used in the production of the raw material copolymer to be hydrolyzed in the present invention is an ester derivative of sorbic acid. Sorbic acid (ie, hexadienes) is
It is a diolefinically unsaturated monocarboxylic acid that can be prepared by ring opening of β-lactone obtained from crotonaldehyde and ketene. The alkyl sorbate used in the present invention preferably has an alkyl group having about 1 to 4 carbon atoms, and can be produced by direct esterification of sorbic acid with methanol, ethanol, propanols or butanols. Preferred alkyl sorbates useful in the present invention are methyl sorbate and ethyl sorbate.

The p-acetoxystyrene component of the copolymer used in the present invention is as described in Corson al, Journal of Organic Chemistry, 23 , 54.
It can be produced by the method described in 4-549 (1958). As described in this article, phenol is acetylated to p-hydroxyacetophenone which is further acetylated to give p-acetoxyacetophenone.
This compound is hydrogenated to p-acetoxyphenylmethylcarbinol, which is then dehydrated to give p-acetoxystyrene.

The copolymer to be hydrolyzed in the present invention is produced by carrying out free radical polymerization of p-acetoxystyrene and dialkyl muconate or alkyl sorbate by a well-known solution, emulsion or suspension polymerization method. This copolymer contains about 10-90% by weight p-acetoxystyrene and about 90-90% by weight.
It is preferred to contain 10% by weight of dialkyl muconate or alkyl sorbate.

The method of the present invention can be implemented, for example, as follows. The 4-acetoxystyrene / dialkyl muconate or alkyl sorbate copolymer is slurried in an alcohol or aqueous base medium to a polymer amount of about 5-40% by weight. This% is weight% based on the total amount of polymer and alcohol or aqueous medium. The slurry is stirred and the catalyst (acid or base) is added. Heating or treatment at about 20-100 ° C. is continued until the polymer becomes soluble in its alcohol or aqueous medium (indicating that the acetoxy groups have been completely converted to phenolic groups). Generally, this heating time is about 1-20
It may be a time range, and sometimes more. When a solution is obtained that indicates the completion of hydrolysis of acetoxy groups to phenol groups, the phenol group-containing copolymer formed is recovered by means well known to those skilled in the art. When the hydrolysis reaction is carried out in an aqueous base solution, the polymer can be recovered from the solution by acid precipitation. When the reaction is an alcoholysis reaction in alcohol, the recovery of the polymer can be carried out by precipitation and aggregation of the polymer in water.

Alcohols useful in the present invention are those having 1 to 4 carbon atoms, ie, methanol, ethanol, propanols and butanols. Preferred alcohols are methanol and ethanol, with methanol being especially preferred.

Acids useful in the present invention are inorganic acids (mineral acids) or organic acids having a dissociation constant in aqueous solution, ie, pKa less than 2, preferably less than 1. Examples of such acids include hydrochloric acid, sulfuric acid, phosphoric acid, methanesulfonic acid, p-toluenesulfonic acid, benzylsulfonic acid, dichloroacetic acid, trichloroacetic acid, iodic acid, boron trifluoride (BF ₃ ), aluminum chloride. , Stannic chloride, etc. The amount of acid used in the process of the present invention ranges from a catalytic amount (ie, about 1 wt% based on the weight of 4-acetoxystyrene polymer) to about 40 wt%.
Up to a degree is enough.

As the base used in the present invention, an alkali metal hydroxide and an alkoxide, preferably sodium methoxide,
Ammonium hydroxide, as well as quaternary ammonium hydroxides, such as tetramethylammonium hydroxide, ethyltrimethylammonium hydroxide, diethyldimethylammonium hydroxide, triethylmethylammonium hydroxide, tetraethylammonium hydroxide, benzyl. There is trimethylammonium hydroxide and choline. The amount of base used is at least about equivalent to the acetoxy groups of the copolymer. A large excess of base can also be used.

Unexpectedly, acid or base hydrolysis of the acetoxy group of a copolymer of p-acetoxystyrene and dialkyl muconate or alkyl sorbate is accompanied by little or no saponification of the ester group portion of the dialkyl muconate or alkyl sorbate. Can be implemented without. Since there is no free carboxylic acid group in the produced copolymer, it becomes possible to carry out the reaction with the phenol group of the produced copolymer without interfering (side reaction). For example, the esterification reaction of the added acid (eg acrylic acid) with the phenolic group should be carried out without the cross-linking reaction that would occur if free muconic acid or sorbic acid groups were present in the copolymer. You can

The copolymer hydrolyzed by the method of the present invention can be used for forming a phosphoric conversion coating for metal treatment and for producing a radiation or photocurable coating. The copolymers can also be used as positive working photoresist materials such as deep UV resist materials and image reversal positive working resist compositions. As yet another application, it can also be used as a polymer modifier and polymer compatibilizer.

Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, parts and% are parts by weight and% by weight, unless otherwise specified.

Production Example A p-acetoxystyrene 90 ml (0.65 mol), toluene 90
A mixture of ml and 1.26 g of 2,2'-azobis (2,4-dimethylvaleronitrile) is degassed by repeating the freeze-pump-thaw cycle three times. To this mixture is added 18 g (0.106 mol) dimethyl muconate in one portion with stirring. The resulting mixture was then heated to 70-80 ° C for 20 hours with stirring under an argon atmosphere,
In the meantime a white translucent syrupy material forms. The syrup is dissolved in 500 ml of acetone and suction filtered to remove insoluble impurities. The resulting clear polymer solution is then flocculated with 14 methanol and acidified with the addition of 10 ml dilute hydrochloric acid to give a white granular polymer. After filtration and drying, 111.6 g of powder are recovered. The conversion rate is 91%. As a result of elemental analysis and proton NMR analysis, the composition of the polymer was found to be p-acetoxystyrene (ASM).
And the molar ratio of dimethyl muconate (MMu) was found to be 4: 1. The Tg (glass transition temperature) of this polymer is 10
6.5 ° C, thermal decomposition start temperature is 260 ° C in nitrogen atmosphere
Is. Its weight average molecular weight (Mw) is 57,650 and its number average molecular weight (Mn) is 33,300.

Example 1 A suitable reactor is charged with 5 parts of an ASM-MMu copolymer having an ASM: MMu molar ratio of 70:30 and 100 parts by volume of a 20% aqueous tetramethylammonium hydroxide solution. The resulting slurry is heated to reflux temperature for 1 hour, at which point the polymer dissolves. The solution is acidified to pH 3 with concentrated hydrochloric acid to precipitate a white granular polymer. After filtration and drying, 3.5 parts of polymer are recovered. As a result of elemental analysis, this product was found to be a p-vinylphenol / dimethyl muconate copolymer.
-It is shown that 1 mol of water is bound per mol equivalent of vinylphenol.

Example 2 A suitable reactor is charged with 50 parts by volume of methanol and 0.5 parts by volume of methanesulfonic acid. Then ASM: MMu molar ratio 80: 2
A suspension forms when 5 parts of 0 ASM-MMu copolymer are added. The suspension is stirred at room temperature until the suspended polymer is completely dissolved (3 hours 15 minutes). Water is added to coagulate the polymer. After filtration and drying 3.57 parts of polymer are recovered.

As a result of elemental analysis, this polymer was found to be a copolymer of p-vinylphenol and dimethyl muconate in a molar ratio of 80:20.
It is a combination of 5 moles of bound water. This copolymer has a Tg of 147 ° C and a molecular weight of 62,750 (Mw) and 29,200.
(Mn).

Example 3 In a suitable reactor, 50 parts by volume of methanol and sodium metal
50 meq and put in a nitrogen atmosphere. After the reaction of sodium to produce sodium methoxide, the ASM: MMu molar ratio
Add 2 parts of 80:20 ASM-MMu copolymer. The resulting slurry is stirred at room temperature overnight (18 hours). By the end of this stirring time a clear solution had formed. The solution obtained is treated with water acidified with 1 part by volume of methanesulfonic acid.
Add to 200 parts to agglomerate the polymer. After filtering, washing and drying in a vacuum oven at 40 ° C., 1.4 parts of p-vinylphenol / dimethyl muconate copolymer are recovered.

Example 4 In a suitable reactor, 50 parts by volume of methanol, ASM: MMu molar ratio 8
Add 2 parts 0:20 ASM-MMu copolymer and 2 parts by volume BF ₃ etherate. After stirring overnight, the clear solution obtained is flocculated in 200 parts of water. After filtration, washing and drying, 1.62 parts of p-vinylphenol / dimethyl muconate copolymer are recovered.

Example 5 A suitable reactor is charged with 25 parts by volume ammonium hydroxide (28% ammonia) and 2 parts ASM-MMu copolymer with 80:20 ASM: MMu molar ratio. Start stirring and heat to heat to reflux temperature. Reflux heating is continued for 17 hours. After the end of this heating time, the resulting clear solution is filtered and the pH is adjusted with
Acidify to 4. After filtration, washing with acidified water and drying, 1.57 parts of p-vinylphenol / dimethyl muconate copolymer are recovered.

Example 6 50 parts by volume of ethanol, ASM: MMu molar ratio 8 in a suitable reactor
Add 2 parts 0:20 ASM-MMu copolymer and 0.5 parts by volume methanesulfonic acid. Start stirring and heat to 70 ° C. After heating at 70 ° C for 50 minutes, the resulting clear solution is flocculated with 300 parts of water. After filtering, washing and drying, 1.51 parts of p-vinylphenol / dimethyl muconate copolymer are recovered.

Example 7 In a suitable reactor, 500 parts by volume of methanol, 3 parts by volume of methanesulfonic acid, and ASM-MMu with an ASM: MMu molar ratio of 90:10.
Add 50 parts of copolymer. The reaction components are stirred at room temperature for 17 hours. The clear solution obtained is filtered and flocculated in 11,200 parts of water. After filtering, washing with 8400 parts of water and drying, 39.3 parts of polymer are recovered. As a result of elemental analysis of this polymer, this polymer was found to be 1/2 as a copolymer of p-vinylphenol and dimethyl muconate in a molar ratio of 90:10.
It is shown to contain moles of bound water. The Tg of this copolymer is 151 ° C. and the molecular weights are 30,600 (Mw) and 18,750 (Mn).

Example 8 To a suitable reactor are added 50 parts by volume of methanol, 0.5 parts by volume of methanesulfonic acid, and 5 parts of an ASM-MMu copolymer with an ASM: MMu molar ratio of 80:20. After stirring for 3 hours at room temperature, the resulting clear solution is agglomerated in 500 parts of water, filtered and dried under reduced pressure at 50 ° C. The resulting p-vinylphenol / dimethyl muconate copolymer (3.93 parts) has a Tg of 151.5 ° C and molecular weights of 33,000 (Mw) and 20,100 (Mn).

Example 9 50 parts by volume of methanol, methanesulfonic acid in a suitable reactor
Add 0.5 parts by volume and 5 parts ASM-MMu copolymer with a 90:10 ASM: MMu molar ratio. After stirring for 3 hours at room temperature, the polymer is coagulated in water, filtered, washed and dried to recover 3.82 parts of p-vinylphenol / dimethyl muconate copolymer. The Tg of this copolymer is 162.5 ° C and the molecular weights are 27,550 (Mw) and 18,750 (Mn).

Example 10 An ASM-MMu copolymer having an ASM: MMu molar ratio of 80:20 is reacted with methanesulfonic acid in methanol at room temperature for 5 hours. The obtained p-vinylphenol / dimethyl muconate copolymer had a Tg of 147.5 ° C and a molecular weight of 44,750 (Mw) and 2
It is 7,150 (Mn).

Example 11 Another copolymer with an ASM: MMu molar ratio of 80:20 was reacted with methanesulfonic acid in methanol for 4 hours at room temperature to give a Tg
P-at 154.5 ° C and molecular weights of 113,400 (Mw) and 56,700 (Mn)
Hydrolyzed to vinylphenol / dimethyl muconate copolymer.

Example 12 In a suitable reactor, 50 parts of a copolymer of p-acetoxystyrene and methyl sorbate in a molar ratio of 80/20, methanol
Add 250 parts by volume and 1.5 parts by volume of methanesulfonic acid. Start the inert gas purge and stir the polymer slurry until it goes into solution for a total of 22 hours at room temperature. After filtration,
The solution is flocculated in 5000 parts of water and washed with 2000 parts of water. Filter to remove water and remove the polymer in the dark at 40
Dry under reduced pressure at ℃. Analysis shows that this polymer is a copolymer of p-vinylphenol and methyl sorbate.

Although the principle, preferred mode and operation of the present invention have been described above, the specific contents disclosed above are merely examples and are not intended to be limiting, and the present invention is not limited to these. . Those skilled in the art will be able to make various modifications within the scope of the invention.

Claims (7)

[Claims] 1. A copolymer of p-acetoxystyrene and a dialkyl muconate or alkyl sorbate is slurried in water or an alcohol, and then the muconic acid alkyl ester group or sorbic acid alkyl ester group is substantially saponified. A method for producing a copolymer of p-vinylphenol and a dialkyl muconate or an alkyl sorbate, which comprises hydrolyzing an acetoxy group with an acid or a base. 2. The method according to claim 1, wherein the hydrolysis reaction is carried out at a temperature of about 20-100 ° C. 3. The starting copolymer is about 10-90% by weight p.
A process as claimed in claim 1 which contains acetoxystyrene and about 90 to 10% by weight of dialkyl muconate. 4. The starting copolymer is about 10 to 90% by weight p.
A process as claimed in claim 1 which contains acetoxystyrene and about 90 to 10% by weight of alkyl sorbate. 5. The method according to claim 1, wherein the hydrolysis is performed with an acid. 6. The method of claim 5, wherein the acid has a pKa of less than 2. 7. The method according to claim 1, wherein the hydrolysis is performed with a base.
The method described.