JPS5913528B2 - Method for producing polyester block copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polyester block copolymers.

Generally, when a polymer is desired to have a high degree of functionality, the polymer is often made up of a wide variety of constituent components, and the method used is to randomly polymerize the various constituent components.

However, since random polymers generally have poor thermal properties, it is difficult to obtain useful 5 polymers. In such cases, one useful method is to produce a block polymer.

For example, hydrophilic polyoxyethylene glycol is added to hydrophobic, high-melting-point crystalline polyethylene terephthalate.
There are methods such as block copolymerization to impart hydrophilicity and improve dyeability, and block copolymerization of polyoxytetramethylene glycol to high melting point crystalline polyester to impart softness. 5 However, when producing a block polymer of polyesters, in addition to the blocking reaction, a randomization reaction also occurs, so it is necessary to suppress or prevent the randomization reaction.

Regarding such methods, methods are known in which phosphoric acid, phosphorous acid and its esters, ammonium salts, metal salts, etc. are added in order to prevent randomization reactions (Japanese Patent Publication No. 46-35500, US Patent No. 2,623,031
(see specification). However, although the addition of phosphoric acid and phosphorous acids is effective in suppressing the randomization reaction,
On the other hand, it has the adverse effect of further worsening the hydrolysis resistance of blocked polyesters obtained from polyesters that generally have poor hydrolysis resistance.

The present inventor has arrived at the present invention as a result of extensive research into a method for preventing such adverse effects and preventing randomization reactions in blocking reactions. That is, the present invention provides a method for producing a polyester block copolymer by melt-mixing two or more polyesters and causing a blocking reaction. R is an m-valent organic residue, and R/ is an alkylene group.

m is 1 or 2, n is O or 1, and when n is O, m is 2. This is a method for producing a polyester block copolymer, which is characterized by adding one or more of the compounds shown below.

The polyester used in the method of the present invention is one that is stable under melt-mixing and blocking reaction conditions,
Included are so-called aromatic polyesters and aliphatic polyesters.

That is, aromatic polyester is one in which the main acid component is an aromatic acid component. Examples of the acid component include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid (2,6-,2,7-,1,4 dicarboxylic acid is particularly preferred), diphenyl dicarboxylic acid, diphenoxyethane dicarboxylic acid, and diphenyl dicarboxylic acid. enylsulfonic acid,
Diphenyl ether dicarboxylic acid, etc., and glycol components such as ethylene glycol, trimethylene glycol, tetramethylene glycol, propylene glycol, pentamethylene glycol, hexamethylene glycol, decamethylene glycol, cyclohexane-1,4-dicarboxylic acid, etc. Methanol, neopentylene glycol, diethylene glycol, triethylene glycol,
Examples include tricyclodecane dimethylol and 2,2-bisβ-hydroxyphenylpropane. Therefore, a combination of two or more of these may be used. For example, adipic acid, sebacic acid, decanedicarboxylic acid,
Aliphatic acid components such as azelaic acid, ε-caprolactone, or poly(tetramethylene oxide) glycol, poly(ethylene oxide) glycol, poly(trimethylene oxide) glycol, poly(hexamethylene oxide) glycol, etc. with a molecular weight of 500 to 5,000. It may also be one obtained by copolymerizing a small proportion of poly(alkylene oxide) glycol components such as the following.

Further, homopolymers comprising an aromatic oxyacid component such as β-hydroxyethoxybenzoic acid or copolymers having this as a component are also included in the aromatic polyester. The aliphatic polyester is one in which the main acid component is an aliphatic acid component.

Examples of acid components include succinic acid, adipic acid,
Azelaic acid, sebacic acid, decanedicarboxylic acid, etc. can be mentioned. Specific examples of glycol components include:
It is the same as that exemplified for the glycol component of the aromatic polyester. Therefore, two or more of these may be used in combination, or, for example, a small proportion of an aromatic acid component such as the above-mentioned terephthalic acid or a poly(alkylene oxide) glycol component may be copolymerized. Also good.

Further, homopolymers comprising an oxyacid component such as ε-caprolactone or copolymers having this as a component are also included in the aliphatic polyester. The aromatic polyester and aliphatic polyester as described above further include:
Tri- or higher-functional compounds such as trimesic acid, trimethylolpropane, pentaerythritol, or O-
It may also be a polyester obtained by copolymerizing one or more monofunctional compounds such as benzoylbenzoic acid, toluic acid, methoxypolyoxyethylene glycol, and octyl alcohol to some extent in a substantially linear manner.

The method of the present invention does not depend on the type of polyester used as described above, but the polyester block copolymer produced exhibits particularly excellent elastic properties, oil resistance, cold resistance, etc., and can be used for various purposes. Therefore, one polyester is an aromatic polyester such as polyethylene terephthalate, polytetramethylene terephthalate, polytrimethylene terephthalate, or polyhexamethylene terephthalate, and the other polyester is polyethylene adipate, polytetramethylene adipate,
Preferably, aliphatic polyesters such as polyhexamethylene adipate and polyethylene sebacate are used.

The above polyesters are produced by a known method.

For example, a dicarboxylic acid or a lower alkyl ester thereof is esterified or transesterified with a glycol to form a glycol ester of the dicarboxylic acid and/or a low polymer thereof, and then the glycol ester and/or its low polymer are formed under high vacuum. It is obtained by heating and stirring a low polymer to cause polycondensation. Any catalyst can be used in the production of the polyesters, but compounds such as antimony, germanium, titanium, manganese, zinc, and lead are preferably used as polycondensation catalysts.

The method of the present invention is carried out by first melt-mixing two or more types of polyesters as described above and causing a blocking reaction.

In the blocking reaction, the polycondensation catalyst used in the production of the polyester exhibits a catalytic effect as it is, so there is no need to add a new catalyst, but if the blocking reaction is slow, the polycondensation catalyst used in the production of the polyester can You can optionally use polycondensation stitches. The blocking reaction varies depending on various conditions such as the type of two or more polyesters to be reacted, their terminal group concentration, reaction temperature, and moisture content in the reaction system, but generally it is carried out for 5 to 120 minutes at 150°C or higher.
In particular, it is carried out at a temperature of 200° C. or higher, more preferably 23° C. or higher, which is higher than the melting point of the polyester.

For the above-mentioned most preferred combination of two or more polyesters, a temperature of 230°C or more and less than 260°C is optimal. The atmosphere during the melt-mixing in which the blocking reaction is carried out may be under increased pressure, reduced pressure, or normal pressure, and in any case, an inert atmosphere is preferable. The blocking reaction is generally 5 to 12
The process is essentially completed by running the reaction for 0 minutes, but a more specific way to confirm this is to sample the polymer from within the system as the reaction progresses and check its softening point and elastic recovery rate in advance. Can be done properly.

It has also been revealed that the point at which the softening point reaches its maximum value generally coincides with the point at which the reaction system becomes transparent; therefore, usefully, the point at which the reaction system becomes transparent can also be used for judgment. It is valid. These points coincide with the point at which the blocking reaction is substantially completed. The elastic recovery rate is preferably determined by a value of 50% or more after 20% elongation and 5 minutes of relaxation.
This blocking reaction can be carried out continuously, batchwise, or by other methods. The method of the present invention is then carried out by adding a compound represented by the following general formula into the reaction system.

)1'' [wherein, R is an m-valent organic residue, R/ is an alkylene group, m is an integer of 1 or more, n is O or 1, and n is O
When , m is 2.

] In the above general formula, the organic residue of R is, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, an alkylene group such as a methylene group, an ethylene group, a tetramethylene group, etc., a cyclohexyl group, a cyclohexylene group, etc. Examples thereof include alicyclic hydrocarbon residues, aromatic hydrocarbon residues such as phenyl groups, phenylene groups, and the like.

The hydrogen atoms of R may be partially substituted with other substituents. In addition, the alkylene group in R/ refers to an unsubstituted alkylene group and an alkylene group having a substituent, such as methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group, etc. Examples thereof include a methylene group, a decamethylene group, an undecamethylene group, and those in which the hydrogen atoms thereof are substituted with an alkyl group.

Such compounds include N-propionylpyrrolidone, N
- Monoacyllatatums such as benzoylphurprolactam, N-benzoyllaurolactam, etc.; N,N'-bisoxazolepyrrolidone, N,N/-bisadipoylpyrrolidone, N,N/-bissebacoylpyrrolidone, N,
N/-bis-terephthaloylpyrrolidone, N,N/-bisisoptalolpyrrolidone, N,N'-bisadipocaprolactam, N,N/-bis-terephthalocaprolactam, N,N'-bisisophthalo Dolphinprolactam, N,N'-bisadipoyllaurolactam, N,N
'N, N/ such as bisterepthaloyl laurolactam, etc.
Examples include lactams acylated with polycarboxylic acids such as -bisacyllactams.

These compounds may be used alone or in combination of two or more. In the method of the present invention, the amount of such a compound added is 0.1 mole based on the total acid component of the blocked polyester. 6 mol% or less, more preferably 0.5
Mol? The content is preferably 5 mol% or less.

The compound may be added once or in two or more times.

The time required for addition and mixing of the compound depends on the mixing method, but generally it can be completed in a very short time.

For example, it is preferable to carry out the reaction within about 5 minutes to 90 minutes, particularly within 60 minutes, both from the viewpoint of suppressing undesirable side reactions of the polymer and from an economical point of view. The mixing may be carried out under any atmosphere of pressurized, reduced pressure, or normal pressure, but after adding the above compound,
Mix under normal pressure for a while (preferably 5 to 30 minutes)
, and then preferably mixed under reduced pressure. This system may contain other additives such as oxidation stabilizers, light stabilizers, ultraviolet absorbers, fluorescent brighteners, matting agents, lubricants, antistatic agents, Flame retardants, flame retardant aids, fungicides, pigments, reinforcing agents, fillers, etc. can be used without any problems. Of course, these may be included in advance during the production of each polyester. In addition, these functions are
It is also possible to use compounds having more than one species at the same time. Stable block polymers obtained by the above-mentioned reaction method, for example, those having an aliphatic polyester as a soft segment and an aromatic polyester as a hard segment are highly useful as elastomers from a practical standpoint.

Next, the present invention will be explained by giving examples. All parts in the middle part of the examples are aqueous, and ηSp/c is the reduced viscosity measured at 35° C. at a concentration of 1.29/l in orthochlorophenol. Example 1 Synthesis of polyester (4) 97 parts of dimethyl terephthalate, 90 parts of tetramethylene glycol, and 0.051 part of tetrabutyl titanate were charged into a reactor equipped with a rectification column, and the internal temperature was adjusted to 160 to 22 mm under normal pressure.
Finished up to C and carried out transesterification.

The reaction was stopped when 95% of the theoretical amount of methanol had been distilled off, the contents were transferred to a polymerization flask, and the degree of vacuum was gradually increased to carry out a polycondensation reaction under high vacuum at a temperature of 240°C. After about 3.5 hours, a high polymer having a reduced viscosity of 1.12 was obtained. This polymer is referred to as polyester (4). Polyester (synthesized by Japan) As long as 87 parts of dimethyl adipate, 90 parts of tetramethylene glycol and 0.051 parts of tetrabutyl titanate were used, the same procedure as in the synthesis of polyester (4) above was carried out (however, the polycondensation time was 5 hours). Go to reduced viscosity 1.
A high polymer of No. 05 was obtained.

This polymer is referred to as polyester (B). Synthesis of block copolymer 25 parts of the above polyester (A) was charged into a polycondensation reactor and melted at 250°C under normal pressure. 50 parts of separately melted polyester (B) was added thereto and the mixture was heated at 250°C under high vacuum. 40
After stirring for several minutes, the molten polymer became almost transparent.

At this stage, 1.8 parts of N,N'-bis-terephthalocaprolactam was added, and the mixture was further stirred for 30 minutes under normal pressure. N,
The reduced viscosity of the polymer before adding N'-bistrephthalocaprolactam was 0.94, and the softening point was 202°C.
30 minutes after addition, the reduced viscosity of the polymer was 1.101, and the softening point was 2000C, with almost no randomization occurring during this time. Comparative Example 1 Polyester (4) was prepared in the same manner as in Example 1 except that N,N'-bis-terephthalocaprolactam was not used.
and (B) were converted into blocks.

The molten polymer became almost transparent after 40 minutes of mixing under high vacuum, the reduced viscosity of the polymer at this time was 1.01, and the softening point was 202°C.
After stirring for several minutes, the softening point of the polymer decreased to 15'C. It can be seen that considerable randomization occurred during this period.
Example 2 Polyesters (4) and (B) were made into a binder in the same manner as in Example 1, and the molten polymer became almost transparent after 40 minutes of mixing under high vacuum.

Claims (1)

[Claims] 1. In a method for producing a polyester block copolymer by melt-mixing two or more thermoplastic polyesters and causing a blocking reaction, after the blocking reaction is substantially completed, the following general formula ▲ There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R is an organic residue of m, and R' is an alkylene group. m is 1 or 2, n is 0 or 1, and when n is 0, m is 2. ] A method for producing a polyester block copolymer, which comprises adding 0.1 to 6 mol % of one or more of the compounds shown below based on the total acid components.