JPS62257930A - Production of polyester having high polymerization degree - Google Patents

Abstract

PURPOSE:To obtain the titled polymer having excellent thermal stability in molten state and containing little terminal carboxyl groups, by adding a bisoxazoline compound to a linear saturated polyester in the presence of a hindered phenolic compound. CONSTITUTION:(A) A linear saturated polyester produced by the polymerization of terephthalic acid and ethylene glycol is melted and added with (B) 0.01-1wt% (based on the component A) hindered phenolic compound {e.g. triethylene glycol- bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate]} and (C) 0.1-10wt% bisoxazoline compound of formula (R1-R8 are H or univalent organic group; D is bivalent organic group; n is 0 or 1) to obtain the objective polymer.

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for producing a high degree of polymerization polyester, and more particularly to a method for producing a high degree of polymerization polyester having a small amount of terminal carboxyl groups. (Prior art) Saturated linear polyesters, especially polyalkylene terephthalates represented by polyethylene terephthalate, have many excellent properties and are therefore widely used as materials for industrial fibers, films, and other molded products. However, higher strength and more extensive hydrolysis resistance and heat resistance are required. In order to impart high strength to polyester, it is effective to increase the degree of polymerization, and to improve hydrolysis resistance and heat resistance, it is effective to reduce the amount of terminal carboxyl groups tt in polyester. By the way, recently, a method for producing polyester with a high degree of polymerization and a small amount of terminal carboxyl groups has been proposed in Japanese Patent Application Laid-open No. 5
Publication No. 5-145734 and JP-A-55-161823
The method proposed in the publication is attracting attention. This method is a method in which a polyester and a bisoquinacillin compound are reacted in a molten state, and the bisoxazoline compound acts as a chain extender that increases the degree of polymerization of the polyester and reduces the amount of terminal carboxyl groups of the polyester. Because it also acts as a low carboxyl group forming agent, it is easy to obtain a polyester with a small amount of terminal carboxyl groups (and a high degree of polymerization (hereinafter sometimes referred to as low carboxyl high polymerization polyester)). However, the low carbo high polymerization polyester produced in this way has the disadvantage that the degree of polymerization decreases rapidly when kept in the F! melt state. If the time is long, it will be difficult to obtain a molded product of high polymerization degree polyester, and the residence time will be short (even if a molded product of high polymerization degree can be obtained, h! 1. Slight variations in mold conditions such as residence time) Due to the influence of
No. 7 and JP-A No. 60-163921 disclose bisoquinacillin compounds and various compounds, such as e/'l,
JP-A-1I860-235834 discloses that the combination of a quaternary phosphonium salt compound, a tertiary bosphine compound, or a quaternary 7-ammonium salt compound can be used in combination with a reaction product of a bisoquinacyline compound and a dicarboxylic acid compound. It has been proposed to use objects. However, all of the obtained low-carbo highly polymerized polyesters still showed a slow rate of decrease in the degree of polymerization in the melt state (and did not have sufficiently satisfactory thermal stability. (Objective of the Invention) The purpose is to produce a highly polymerized polyester obtained by reacting a polyester with a bisoxazoline compound, which has good thermal stability in the melted state and has good moldability without being affected by variations in melt molding conditions. An object of the present invention is to provide a method for producing a highly polymerized polyester. (Structure) As a result of studies to achieve the above object, the present inventors have prepared a polyester and a bisoxazoline compound in the presence of a hindered phenol compound. The present invention has been achieved based on the discovery that the thermal stability of the obtained low-carbo highly polymerized polyester in the molten state can be dramatically improved by reacting the polyester with a substantially linear saturated polyester. and at least one bisoxazoline represented by the following general formula (11% formula %) in an amount of 0.1 to 10% by weight based on the polyester,
0.01 to 1.0% to the polyester. This is a method for producing a highly polymerized polyester, which is characterized by reacting uMM'lz, a hindered phenol compound example Eva, in a molten state. In the present invention, the acid components constituting the 45-saturated polyester include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenyl dicarboxylic acid, diphenylsulfone dicarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl ether dicarboxylic acid, methyl terephthalic acid, methyl isophthalic acid, etc. Like 7! Aromatic dicarboxylic acids, adipic acid, cepatic acid, decanedicarboxylic acid,
Aliphatic dicarboxylic acids such as dodecanedicarboxylic acid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid,
Examples include oxycarboxylic acids such as 8-oxycaproic acid, oxybenzoic acid, and hydroxyethoxybenzoic acid, and among these, aromatic dicarboxylic acids, particularly terephthalic acid, are preferred. Moreover, in the above saturated polyester,
When the acid component is a dicarboxylic acid, the Glyfur component includes ethylene glycol, trimethylene glycol,
Examples include tetramethylene glycol, hexamethylene glycol 1 decamethylene glycol, cyclohexane dimethylol, and among these, ethylene glycol and tetramethylene glycol are particularly preferred. It is also possible to use polyoxyfulkylene glycol as part of the glycol component, such as polyoxyethylene glycol, polyoxypropylene glycol, polyoxytetramethylene glycol, and copolymers thereof. When polyoxyalkylene glycol is used, its average molecular weight is preferably 5
00~5aoo, more preferably (600~4θ00
, particularly preferably from 800 to 3,000, and the roughness used is about 5 to 85 times in polyester, preferably 10
The copolymerized amount is about 80% by weight, more preferably 15% to 75% by weight.@These copolymerized polyesters are preferably bootsk copolymers. In addition, the saturated polyester may include trifunctional or higher functional compounds within a substantially linear range (for example, 1 mole or less relative to the total fI! component) such as evaporation, trimethylolpropane, pentaerythritol, trimellitic acid, etc. , pyromellitic fig may also be copolymerized with a monofunctional compound such as benzoylbenzoic acid, diphenylcarbon tR, etc. Any method may be employed to produce such polyester. For example, in the case of polyethylene terephthalate, terephthalic acid and ethylene glycol are subjected to a Naomata ester reaction, or dimethyl terephthalate and ethylene glycol are subjected to a transesterification reaction to form a glycol ester of terephthalic acid and/or a low polymer thereof. The most common method is to produce the product by combining the first stage reaction, which involves heating the first stage reaction product under reduced pressure, distilling off the generated glycol, and polymerizing it. The degree of polymerization and the amount of terminal carboxyl groups are determined by the degree of polymerization and the amount of terminal carboxyl groups of the target product polyester.

[A] - Although it cannot be generally specified, the degree of polymerization is usually 0.4 or more, preferably 0.5 to 0.8 in terms of limiting viscosity in the direction, and the terminal carboxyl group It is usually 5 to 15 υfi1 m/10 'j
'Polymer, preferably 15-100 equivalents/1θ6 I
It is a polymer. In the reaction of the first stage and the second stage, any catalyst can be used as necessary, and additives such as colorants, matting agents, stabilizers, hardeners, etc. can be used as necessary. A fuel agent, an antistatic agent, an agent for facilitating dyeing, etc. may be added. In the present invention, it is important to react the linear saturated polyester thus obtained with the bisoxazoline compound in a molten state in the presence of a hindered phenol compound. Here, since the hindered phenol compound was added after the reaction between the polyester and the bisoxazoline compound was substantially completed, the f
6. A dramatic improvement in thermal stability in the molten state cannot be achieved. The bisoxazoline compound used in the present invention is represented by the following general formula txt. In the general formula +11, %R1 to R6 are each a hydrogen atom or a -valent organic group, and preferred examples of the -valent organic group include a furkyl group having 1 to 10 carbon atoms and a 6 to 12 carbon atoms.
Examples include a 7-aryl group having 5 to 12 carbon atoms, a 7-ral group having 8 to 20 carbon atoms, and the like. Among these R1 to G, which may be the same or different, it is preferable that IL -R are all hydrogen atoms. In addition, 1) in the formula is a divalent organic group, such as a fullkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 12 carbon atoms, a cycloalkylene group having 5 to 2 carbon atoms, and a cycloalkylene group having 8 to 2 carbon atoms. Examples include 20 7ralkylene groups. More specifically, alkylene groups include methylene, ethylene, propylene, methylene, bentylene, hemethylene, octamethylene, nonamethylene, decamethylene, dimethylmethylene, etc., and arylene groups include phenylene, naphthylene, and dimethylmethylene. 0O-1-8-1-
8o2-, -0)]2-1- (3H20H2-1-0(CH,)2-, etc.) 4 is an example, and C is a cycloalkylene group, and C is a cyclohexylene group. In the formula, n is 0 or 1, and those where n is 1) are particularly preferred. Specific examples of the bisoxazoline compound represented by the general formula (1) include 2.2'-bis(2-oxacillin) and 2.21-bis(4-methyl-2-oxazoline).
, 2.2'-bis(,4,4'-dimethyl-2-oxazoline)%212'-bis(4-ethyl-2oxazoline), 2.2r-bis(4,4diethyl-2-oxacillin), 2.2'-bis(4-propyl-2-oxacillin), 2.21-bis(4-g-2-oxacillin)
In), 2,2'-bis(4-hexyl-2-oxazoline), 2,2'-bis(4-7enyl-2-oxacillin), 2,2'-bis(4-shif-hexyl- 2-oxacillin), 2.2'-bis(4-benzyl-2-oxazoline), 2.2'-o-phenylenebis(2-oxazoline), 2.2'-m-7enylenebis(2
-oxazoline), 2,2'-o-phenylenebis(2
-oxazoline), 2+2'-9-phenylenebis(
4-methyl-2-oxazoline), 2,2'-p-phenylenebis(4,4-dimethyl-2-oxazoline)
, 2.2' m-phenylenebis(4-methyl-2-
oxazoline), 2,21-m-phinidine bis(4,
4-dimethyl-2-oxazoline), 2,2'-ethylenebis(2-oxazoline), 2,2'-tetramethylenebis(2-oxazoline), 2,2'-hexamethylenebis(2-oxazoline), 2.2'-Octamethylenebis(2-Oquinacillin), 2.2'-Decamethylenebis(2-Oquinacillin), 2.2'-Ethylenebis(
4-methyl-2-oxazoline), 2,2'-tetramethylenebis(4,4-dimethyl-2-oxazoline), 2
, 2'-9,9'-diphenoxyethane bis(2-
oxazoline), 2,2'-Schif-hexylenebis(2
-oxazoline), 2,2'-diphenylenebis(2-
Oxacillin) etc. can be given. Such a bisoxazoline compound may be used alone or in combination of two or more plants. If the amount is less than 0.1% by weight, it will not be possible to obtain a low-carbo'4j-point polyester, and if the amount exceeds 4% by weight,
The effects such as the effect of reducing the terminal carboxyl group type of polyester reached the sum of &1, and no further effects can be expected. A more preferable usage amount is 0.2■ amount Chino all 5 layers! Good for hemorrhoids 'JL< is U, 3. djl1% to 31 companies dixyphenyl)propionate and), 1,6-hexanethiolubis[: 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]2.4-
Bis-(n-octylthio)-6-(4-human-oxy-
3,5-di-t-glyanisono)-1,3,5-triazine, pentaerythrityl-tetrakis(3-(3
, 5-:/-1-butyl-4-hydroxyphenyl)propionate), 2,2-thio-diethylenebis(3-
(3,5-di-t-glythyl-4-hydoxyphenyl)
propionate], octadecyl-3-(3,5-di-
t-Gutyl-4-human-xyphenyl)propionate, 2,2-thiobis(4-methyl-6-t-butylphenol), N,N'-hexamethylenebis(3,
5-di-augtyl-4-hydroxy-human-cinnamamide), 3.5-di-tert-butyl-4-hydroxy-penenulfosphonate diethyl ester, 1.3.
Examples include 5-tos/thiru2.4.6-)lis(3,5-di-t-glythyl-4-human c-xybenzylphosphonoethyl)calcium. 1. Especially,
OctadecyIt/-3-(3,5-di-t-butyl-4
-hydroxyphenyl)bouvionate, 2,2-thio-diethylenebia, L3 (315-diτ-7'
/'-4-hydroquinphenyl)propio-1]
(7) Such hindered phenol compounds may be used alone or in combination of two or more. Addition of hindered phenol compounds used in the present invention J
t is o, ut to t, ott% relative to the polyester. If the amount is less than 0.01 heavy IL, the effect of improving arc stability, which is the objective of the present invention, will not be significant (if it exceeds 1,0 heavy IL, no further effect can be expected. The hindered phenol compound can be mixed with a bisoxazoline compound to form a polyester [4].
It may be blended into the polyester in advance. In the present invention, polyester and a predetermined amount of a bisoxazoline compound are reacted in a molten state in the presence of a predetermined amount of a hindered phenol compound. Reaction temperature at this time) K+1 above the melting point of polyester and below 320°C, 4!
The melting point of the polyester is preferably higher than or equal to 290°C or lower. Further, the reaction pressure may be increased, but preferably a bed pressure or a reduced pressure. Preferred reaction times are 30 seconds to 60 minutes, more preferably 1 minute to 30 minutes, more preferably 1 minute to 15 minutes. This reaction can be carried out in a 1m reactor in a normal polyester polymerization reactor. : Not only can the reaction be carried out under mixing and stirring, but also, for example, it is possible to carry out the reaction by mixing the two in an extruder to achieve a high degree of aggregation. For example, there are backing threads and film-forming products (which can be mixed during injection molding of plastics). However, the rate at which the melting state V decreases by 1 degree is high, and the influence of variations in the bath melt forming conditions is easily affected. , according to the invention, in the presence of the IQIC hindered phenolic compound of the reaction -c, <
% low carbo high polymerization degree polyester has significantly improved thermal stability in the M melt state compared to conventional low carbo high polymerization polyester, and is not affected by variations in melt molding conditions. It can be stably molded without any problems, and yarn breakage during melt spinning can be significantly reduced. (Effect of the invention) Low carb achieved by the present invention? The IIJ2i polyester can be preferably used as a molding material for polyester molded products that require high strength and low carboxyl group content, such as polyester fibers, films, and plastic molded products. (Example) Hereinafter, the present invention will be specifically explained using Examples. Example 1 Intrinsic viscosity [η]υ, 80, terminal carboxyl group amount (OO
OH) 38 wins! IL/106 g of polyethylene terephthalate) 1 LJt 1 mjt part was added with a hindered phenolic compound and a bisoxazoline compound in the bulk addition 1 shown in Table 1, and then the obtained The mustard compound was prepared in an extruder and bath-melt extruded at a temperature of about 300° C. for 41 f 1 hour as shown in al. Superior intrinsic viscosity of the polymer after extrusion [η]
and terminal carboxyl group wrinkles (OOOH) are also shown in Table 11C. In Table 1, Ya 2 and A5 can obtain a low-carbo highly polymerized polyester, but since the amount of the hindered phenol compound added is υ, 01% it%, the molten state of the obtained polyester is ``cN bonding decreases rapidly. In addition, in A3, when the amount of bisoxazoline compound added is o, x
Since it is less than iffi%, a low carbo highly polymerized polyester cannot be obtained. On the other hand, the low-carbo-highly polymerized polyester obtained from Al & Bim 4 containing the bisoxazoline compound and the hindered 7 di/-ol compound in the amounts specified in the present invention is thermally stable in the molten state. The properties are significantly improved compared to MU 2, RI 3 and BINO NI 5. Comparison 11 In A1 curve fL5 in Table 1 of Example 1, the extruded polyester was cooled with an extruder residence time of 5 minutes, and then held at 300°C under a nitrogen atmosphere to determine the intrinsic viscosity (
The rate of decline in 1) was investigated. However, octadecyl-3-(3,5-di-t-7'thyl-4-
0.1% by weight of hydroxyphenyl)tubionate was added. Table 2 shows the specific viscosity [η] of the polymer. Table 2 (Comparative Example Comparative Example 2 Table 1 of Example 1)
The songs in which the type and/or amount of the bisoxazoline compound or hindered phenol compound is changed are as follows in Example 1.
The solid-state viscosity of the polymer after extrusion from the extruder was measured in the same manner as above, and is also shown in Table 3. Example 2 Mu1 in Table 1 of Example 1 and a bisoxazoline compound and a dark phenol compound in the amount shown in ≦5 were mixed with polyester, and then 31 (melted and discharged at 1 ° C. and cooled) was mixed with polyester. After solidification, the yarn was taken off at a speed of 2,500 mm/min. At this time, the yarn breakage of the yarn was &101.5 inches, while Ya 5 was 3.5 inches. It is impossible to achieve a perfect piston flow in the ?tA!I state, and it is impossible to eliminate the variation in residence time. , the polymerization degree of a portion of the polymer with a long residence time decreases, and the discharged low polymerization degree portion is easily broken, resulting in frequent spinning yarn breakage. Polymers with improved properties do not have a degree of polymerization that decreases to the extent that they cause yarn breakage when the residence time during spinning varies moderately, making it possible to reduce the amount of yarn breakage caused by spinning.

Claims (4)

[Claims] (1) Substantially linear saturated polyester and 0.1 to 10% by weight of the above polyester according to the following general formula (I) ▲There are numerical formulas, chemical formulas, tables, etc.▼...(I) [In the formula, R_1 ~R_8 is a hydrogen atom or a monovalent organic group, and R_1 to R_8 may be the same or different. D is a divalent organic group, and n is 0 or 1. ] at least one bisoxazoline compound represented by 0.01 to 1.0% by weight based on the polyester.
A method for producing a highly polymerized polyester, which is characterized by reacting it in a molten state in the presence of a hindered phenol compound. (2) Bisoxazoline has the following general formula (I') ▲ Numerical formulas, chemical formulas, tables, etc. are available▼......(I') [In the formula, R_1 to R_8 are the same as the above general formula (I).
] A method for producing a highly polymerized polyester according to claim (1), which is a bisoxazoline represented by the following. (3) Hindered phenol compound is octadecyl-
3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate and/or 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate Claim No. (
1) A method for producing a high degree of polymerization polyester as described in section 1). (4) Saturated polyester has the following general formula (II) ▲ There are numerical formulas, chemical formulas, tables, etc. ▼ ... (II) [In the formula, n is 2 or 4. ] A method for producing a highly polymerized polyester according to claim (1), which is a polyester having a repeating unit represented by the following as a main structural unit.