JPS6045642B2 - Thermoplastic resin manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a thermoplastic resin having significantly improved heat resistance stability and processability, and more specifically, a method for producing a thermoplastic resin having significantly improved heat resistance stability and processability, and more specifically, a method for producing a thermoplastic resin having significantly improved heat resistance stability and processability. The present invention relates to a method for producing a thermoplastic resin, in which a copolymer made of a vinyl monomer is imidized and reacted with ammonia and/or a first group amine in the presence of a tertiary amine.

Various methods for producing copolymers comprising aromatic vinyl monomers, maleic anhydride, and other vinyl monomers have been known.

(Special Publication No. 40-1582, Special Publication No. 31953-1973, Special Publication No. 10156-1977). These polymers copolymerized with maleic anhydride have a high heat deformation temperature, but due to the presence of acid anhydride groups derived from maleic anhydride in the copolymer chain, they are resistant to water at high temperatures. It easily undergoes chemical changes and decomposes not only when exposed to heat, but also when subjected to injection or extrusion processing, and when the processed product is not brought into contact with water or steam, or exposed to high temperatures. In this case, there is a drawback that mechanical properties, especially impact strength, are reduced.

The present invention aims to solve these drawbacks, and it is an aromatic vinyl monomer having a specific reduced viscosity,
A copolymer consisting of maleic anhydride and other vinyl monomers is reacted with ammonia and/or a primary amine in the presence of a tertiary amine, and 90% or more of the acid anhydride groups in the copolymer are By using an imide group, it is intended to provide a method for producing a thermoplastic resin that is stable to water and heat while maintaining the heat distortion temperature of the copolymer.

100ml of methyl ethyl ketone solution at temperature 30C. Aromatic vinyl monomer 50-50 whose reduced viscosity ηSp/C>0.3 of a polymer solution containing 1.0y of polymer in t
When imidizing a copolymer consisting of 8% by volume of maleic anhydride, 5 to 4% by volume of maleic anhydride, and 0 to 3% by volume of a vinyl monomer copolymerizable with these, in the presence of a tertiary amine. , the copolymer and ammonia and/or primary amine were heated at a temperature of 8.
It is characterized in that it is reacted at 0 to 350°C and 90 mol% of the acid anhydride groups are converted to imide groups. The present invention will be explained in more detail below.

Generally, aromatic vinyl monomer and maleic anhydride are
They have strong mutual copolymerizability, and when polymerized under normal radical polymerization conditions, the molar ratio of aromatic vinyl monomer and maleic anhydride is 1.
: An alternating copolymer having the composition of
The aromatic vinyl-maleic acid copolymer (hereinafter referred to as aromatic vinyl-maleic acid copolymer) has a reduced viscosity of 0.3 or more, preferably 0.33 or more, which is substantially slower than the polymerization rate of the aromatic vinyl monomer. Radical polymerization is carried out while adding maleic anhydride at a rapid rate. be.

In the present invention, reduced viscosity means 100 mL of a methyl ethyl ketone solution at a temperature of 30'C. 1.0q of polymer in 1
This is the viscosity of the contained polymer solution.

In the present invention, aromatic vinyl-malein is particularly used. The composition and reduced viscosity of the acidic copolymer are important, and its composition is 50 to 80% by weight of aromatic vinyl monomer, 5 to 40% of maleic anhydride, and vinyl monomer copolymerizable with this. 0-3
The reason for limiting it to 0% is that it is a copolymer that maintains a high heat distortion temperature and mechanical strength, and the reason why it has a reduced viscosity of 0.3 or higher is because it is a copolymer that can be formed even when imidized with a copolymer of 0.3 or lower. This is because when an imidized polymer is made into a molded article, its mechanical properties are poor.

In the aromatic vinyl-maleic acid copolymer used in the present invention, the aromatic vinyl monomers include styrene, α-methylstyrene, vinyltoluene, t-butylstyrene,
Among styrene monomers such as chlorostyrene and substituted monomers thereof, monomers such as medium styrene and α-methylstyrene are particularly preferred.

Vinyl monomers that can be copolymerized with these include vinyl cyanide monomers such as acrylonitrile, methacrylonitrile, and αs-chloroacrylonitrile, and acrylic acids such as methyl acrylate, ethyl acrylate, and butyl acrylate. Ester monomers, methacrylic ester monomers such as methyl methacrylic ester and ethyl methacrylic ester, vinyl carboxylic acid monomers of acrylic acid and methacrylic acid, acryl amide, methacrylic amide, acenaphthylene and N-vinylcarbazole etc., among which acrylonitrile,
Monomers such as acrylic esters and methacrylic esters are particularly preferred.

Ammonia and primary amines used in the imidization reaction of the present invention may be in either an anhydrous or aqueous solution state, and specific examples of primary amines include methylamine, ethylamine, n-propylamine, IsO-propyl amine,
Examples include alkyl amines such as butylamine, pentylamine, and cyclohexylamine, aromatic amines such as aniline, tolylamine, and naphthylamine, and halogen-substituted aromatic amines such as chloro- or bromo-substituted aniline.
The amount used is at least the molar equivalent of maleic acid in the aromatic vinyl-maleic acid copolymer. Preferably, the molar equivalent is 1 to 1.3 times the molar equivalent of maleic acid. In the present invention, the aromatic vinyl-maleic anhydride copolymer as described above is reacted with ammonia and/or a primary amine in the presence of a tertiary amine, but in the absence of a tertiary amine, an imidization reaction occurs. takes a long time and reduces the imidization rate to 90
It is difficult to make it more than mol%.

The amount of tertiary amine added is preferably 0.001 molar equivalent or more based on the maleic anhydride groups of the copolymer. Further, an imidized polymer having an imidization rate of 90 mol % or less is superior to a non-imidized maleic anhydride copolymer, but is also undesirable because it has insufficient stability against water and heat.

In the present invention, the imidization reaction of the maleic anhydride copolymer is carried out in the form of a lump, in a solution, and in a suspended state in a non-aqueous solution, but when carried out in a solution state or a suspended state in a non-aqueous medium, It is preferable to use an ordinary reaction vessel, such as an autoclave, but if the reaction is carried out in a bulk molten state, an extruder equipped with a devolatilization device may be used.

In addition, in the present invention, the imidization is shown by the following reaction formula, but R: H1 alkyl group, aromatic group The ring-opening reaction of reaction formula 1 and the ring-closing reaction of May be performed continuously.

The reaction temperature for imidization is about 80-350'C, preferably 100-300'C.

If the temperature is lower than 800C, the reaction rate is slow and the reaction takes a long time, which is not practical.

On the other hand, if the temperature is 350°C or higher, the physical properties will deteriorate due to thermal decomposition of the polymer. As the tertiary amine, trimethylamine,
Examples include triethylamine, tripropylamine, tributylamine, N,N-dimethylaniline, N,N-diethylaniline, and the like.

Examples of the solvent for imidizing the maleic anhydride copolymer in a solution state include acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, tetrahydrofuran, and dimethyl formamide, among which methyl ethyl ketone is particularly preferred.

When imidizing in a suspended state in a non-aqueous medium, the non-aqueous medium includes pentane, hexane, heptane, octane, 2-
There are aliphatic hydrocarbons such as methylpentane, cyclopentane, and cyclohexane.

The imidized maleic anhydride copolymer produced by the method described above maintains a high heat distortion temperature, has a high degree of stability against water and heat, and has other properties. It also has excellent mechanical properties. This imidized polymer has good compatibility with styrene-acrylonitrile copolymer (SAN resin), ABS resin, MBS resin, etc., and can be mixed with these resins by a conventional method. It is also possible to further add stabilizers, plasticizers, lubricants, fillers, colorants, etc. to the imidized polymer of the present invention. The present invention will be explained below with reference to Examples.

Note that all parts in the examples are expressed as parts by weight. Example 1 1 Production of aromatic vinyl-maleic anhydride copolymer (a
) In an autoclave equipped with an agitator, 75 parts of styrene was charged, and the inside of the autoclave was purged with nitrogen gas, and then heated to a temperature of 80'C.

To this was added a solution in which 25 parts of maleic anhydride, 0.3 parts of benzoyl peroxide and 4 parts of methyl ethyl ketone were dissolved in one phase. The temperature was maintained at 80'C for an additional 2 hours after the addition. A portion of the viscous reaction solution was sampled and unreacted monomer was quantified by gas chromatography to calculate the polymerization rate and the content of maleic anhydride in the polymer. 150 parts of methyl ethyl ketone was added to the remaining reaction solution, cooled to room temperature, poured into 80 U of methanol while stirring vigorously, and dried to obtain a white powdery polymer. The reduced viscosity ηSp/C of the polymer is the polymer concentration C=1.0V/100ml methyl ethyl ketone,
Measurements were taken at 30°C. In addition, the blending ratio of monomers (b
A variety of aromatic vinyl-maleic anhydride copolymers were prepared and their reduced viscosity and other properties were measured in the same manner as described above except for making various changes as shown in () to (f).

These conditions and their results are shown in Table 1. 2. Preparation of imidized polymer (very part) of the maleic anhydride copolymer obtained in (a) and 0.3 parts of triethylamine were dissolved in methyl ethyl ketone 7(2) in an autoclave, and the maleic anhydride groups were added to the solution. 8.68 parts of aniline, which was 1.05 times the molar equivalent, was added thereto and the reaction was carried out at 130'C for 7 hours.

The reaction solution was cooled to room temperature, poured into 300 parts of vigorously stirred methanol, separated and dried to obtain an imidized polymer.
According to C-13 NMR analysis, the conversion rate of acid anhydride groups to imide groups was 99%. 30TWL of this imidized polymer
It was extruded into pellets using a screw extruder equipped with a φ devolatilization device. The performance of this polymer is shown in Table 2. Example 2 The same operation as in Example 1 was carried out except that the maleic anhydride copolymers obtained in (b) to (f) of Example 1 were each used at 3 ωV.

In addition, aniline has 1.0% for each maleic anhydride group.
05 times molar equivalent was used. The performance of these imidized polymers is shown in Table 2. Example 1 except that no tertiary amine was used as a catalyst for the maleic anhydride copolymers obtained in Example 1 (a) and (C) for comparison.
The same operation as above was performed and the performance was measured.

The results are shown in Table 2 Experiment No. 7 and NO. 8.
Example 3 0.1 part of the maleic anhydride copolymer powder 308V1 trimethylamine obtained in Example 1 a was suspended in m parts of n-hexane in a stirred autoclave.

Two parts of methylamine were added to this and the reaction was carried out at 130°C for 7 hours. The reaction suspension was cooled to room temperature, passed through the mouth, and dried to obtain an imidized polymer. These results are shown in Table 2 Experiment N
O. 9. The measured values in Table 2 were carried out by the following method.

Claims (1)

[Claims] 1. 100ml of methyl ethyl ketone solution at a temperature of 30°C
Aromatic vinyl monomer 50 whose reduced viscosity η sp / C > 0.3 of a polymer solution containing 1.0 g of polymer
In the presence of a tertiary amine, when imidizing a copolymer consisting of ~80% by weight, 5% to 40% by weight of maleic anhydride, and 0 to 30% by weight of a vinyl monomer copolymerizable with these,
A method for producing a thermoplastic resin, characterized in that the copolymer is reacted with ammonia and/or a first set of amines at a temperature of 80 to 350°C, and 90 mol% or more of acid anhydride groups are imide groups. 2. The copolymer according to claim 1 in a bulk state,
The manufacturing method according to claim 1, wherein the reaction is carried out in one type of state selected from a solution state and a suspension state in a non-aqueous solution. 3 The aromatic vinyl monomer is styrene and/or α-
The method according to claim 1, which uses a copolymer of methylstyrene. 4. The production method according to claim 1, wherein the copolymerizable vinyl monomer is one or more selected from acrylonitrile, acrylic ester, and methacrylic ester. 5. The method according to claim 1, wherein the catalyst is trimethylamine or triethylamine.