JPS63145328A - Production of modified polyester - Google Patents

Abstract

PURPOSE:To obtain the title polymer which can give moldings such as films and fibers excellent in surface smoothness and slidability without troubles, by transesterifying a dicarboxylic acid (derivative) with a glycol in the presence of a specified long-chain alkyl group-containing esterifiable compound. CONSTITUTION:100pts.wt. dicarboxylic acid (derivative) (A) [e.g., terephthalic acid (dimethyl ester)] is transesterified with, e.g., 70pts.wt. glycol (B) (e.g., ethylene glycol) and 0.001-30wt% (based on the polyester) 6C or higher long-chain alkyl group-containing esterifiable compound (C) selected from among an aliphatic carboxylic acid anhydride (e.g., 2-octadecylsuccinic anhydride), a lactone (e.g., tau-stearolactone) and an epoxide (e.g., 1,2-eicosylene oxide) in the presence of, optionally, external or internal particles (D) such as calcium carbonate, TiO2 and silica.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a method for producing modified polyester. The present invention relates to a method for producing a modified polyester that significantly improves properties.

[Prior art] Polyester, especially polyethylene terephthalate, has excellent mechanical and chemical properties, so it is widely used as fibers for clothing and industrial use, as well as films for magnetic tape, photography, capacitors, etc. It is used.

When used in the above applications, in addition to surface flatness, ease of slipping is required from the viewpoint of workability during molding of films, fibers, etc., and handling of the product.

Conventionally, as a method to improve slipperiness, silicon oxide,
A method of adding inert particles such as titanium dioxide, calcium carbonate, talc, clay, etc. (external particle method); ■ A method of generating fine particles based on the catalyst component and color inhibitor used during polyester synthesis (internal particle method) has been proposed, and a method is known in which protrusions are formed on the surface of polyester using fine particles to improve slipperiness. However, when using such particles, it is unavoidable that the surface flatness is impaired due to the inclusion of coarse particles or aggregated particles, and there is a limit to the ability to provide smoothness while maintaining surface flatness. .

Additionally, as additives other than particles, a method using montan wax salt (Japanese Unexamined Patent Publication No. 56-139551) and a method using an aliphatic monocarboxylic acid (Japanese Unexamined Patent Publication No. 27-195143) are also available.
etc. have been proposed. Although these compounds improve slipperiness to some extent, increasing the amount of these compounds in order to further improve slipperiness results in poor dispersion and the formation of foreign particles and crater-like particles. This results in unevenness, resulting in insufficient surface flatness as in the case of using particles. Furthermore, if these compounds are added before the end of the polycondensation reaction for the purpose of improving dispersion, these compounds will scatter during the polycondensation reaction, resulting in insufficient lubricity or the formation of coarse foreign matter. Problems such as poor ejection, film tearing, and thread breakage occur during fiber formation.

In this way, in the conventional technology, polycondensation process or film,
It has been virtually impossible to create a polyester that does not cause trouble during molding of fibers or other molded products and that satisfies both surface flatness and slipperiness. Furthermore, in order to accommodate various uses, it has been desired to modify the surface properties of polyester itself.

[Problems to be Solved by the Invention] In such conventional techniques, it has been difficult to obtain a film that has both sufficient surface flatness and slipperiness. The inventors of the present invention have arrived at the present invention as a result of intensive studies to eliminate such drawbacks.

In other words, the purpose of the present invention is to provide a method that eliminates trouble during the polycondensation process or during the molding of molded products such as films and fibers, simultaneously satisfies the surface flatness and slipperiness of the resulting molded products, and significantly improves the surface properties. Our objective is to provide modified polyester.

[Means for Solving the Problems] The object of the present invention is to produce a polyester from a dicarboxylic acid or a derivative thereof and a glycol by reducing the number of carbon atoms from 0.001 to 30 parts by weight based on 100 parts by weight of the polyester. This is achieved by a method for producing a modified polyester characterized by adding at least one long-chain alkyl group-containing ester-forming compound selected from acid anhydrides, lactones, and epoxides having 6 or more alkyl groups.

In the long-chain alkyl group-containing ester-forming compound, the number of carbon atoms in the alkyl group must be 6 or more. The preferred number of carbon atoms is 10 to 30, which are commonly available, and straight chain alkyl groups are preferred. The number of carbon atoms in the alkyl group is 5
If it is below, sufficient slipperiness cannot be obtained even if it is added to polyester.

Specifically, the compounds include 2-hexyl succinic anhydride, 2-octyl succinic anhydride, 2-decyl succinic anhydride, 2-dodecyl succinic anhydride, 2-tetradecyl succinic anhydride, 2-hexadecyl succinic anhydride, 2-octadecyl succinic anhydride, 2-eicosyl succinic anhydride, 3-
Aliphatic carboxylic acid anhydrides such as dodecyl glutaric anhydride, 3-tetradecyl glutaric anhydride, 3-hexadecyl glutaric anhydride, 3-octadecyl glutaric anhydride, γ
- Lactones such as laurolactone, γ-palmitolactone, γ-stearolactone, δ-laurolactone, δ-palmitolactone, δ-stearolactone; and 1.
2-Decylene oxide, 1,2-tetradecylene oxide, 1,2-hexadecylene oxide, 1,2-
Examples include epoxides such as octadecylene oxide and 1,2-eicosylene oxide, but are not limited thereto.

In the present invention, the amount of the long-chain alkyl group-containing ester-forming compound added is 0.00 parts by weight per 100 parts by weight of the polyester.
001 to 30 parts by weight, preferably 0
．． 01 to 10 parts by weight. If the amount is less than 0.001 parts by weight, the slipperiness of the film will be insufficient, and if it exceeds 30 parts by weight, the mechanical strength when formed into a film or fiber will be poor.

The compound can be added to the polyester at any time. For example, a method of addition reaction during the polycondensation reaction or a method of kneading with an extruder can be used, but under normal polymer production conditions, the compound can be converted into polyester, its low polymer, or the hydroxyl groups present in its raw materials. It is more preferable to add and react before the end of the polycondensation reaction in order to sufficiently react with the polyester component, carboxyl group, and ester group to form a chemical bond with the polyester component. Alternatively, a method can be used in which a master polyester is prepared in which a large amount of an ester-forming compound containing a long-chain alkyl group is added, and the master polyester is diluted with a polyester to which no additive is added.

The polyester in the present invention refers to a polyester comprising a dicarboxylic acid or a derivative thereof and a glycol. As the dicarboxylic acid or its derivative, terephthalic acid or its lower alkyl ester is mainly used, but other acid components include, for example, isophthalic acid, p-β-oxyethoxybenzoic acid, diphenylsulfone 4,4-monodicarboxylic acid. , diphenyl ether 4'4
-Dicarboxylic acid diphenoxyethane One or two of 4,4'-dicarboxylic acid, adipic acid, sebacic acid, dodecanedioic acid, azelaic acid, 5-sodium sulfoisophthalic acid, or lower alkyl or glycol esters thereof. The above can be used together.

The main glycols include ethylene glycol and tetramethylene glycol-1,4, but other glycol components include propylene glycol, trimethylene glycol, neopentyl glycol, hexamethylene glycol-1,6, and pentamethylene glycol-1. , 5,1,4-cyclohexanediol, 1.
One or more of 4-cyclohexane dimetatool, 1°4-bisoxyethylene glycol, bisphenol A1 polyoxyethylene glycol, or the like may be used in combination.

Any method can be used to produce the polyester made of the dicarboxylic acid or its derivative and glycol. For example, polyethylene terephthalate, which is composed of a terephthalic acid component and an ethylene glycol component, is produced by directly esterifying terephthalic acid and ethylene glycol, or by reacting terephthalic acid and ethylene oxide to form a glycol ester of terephthalic acid or its derivatives. a first stage reaction to produce a polymer;
It is produced by a second step in which the reaction product of the first step is subjected to a polycondensation reaction.

In the present invention, external particles or internal particles can also be made to coexist with the long-chain alkyl group-containing ester-forming compound within a range where the purpose can be achieved.

The purpose of the present invention is to add a specific ester-forming compound to polyester to simultaneously satisfy surface flatness and slipperiness when molded into films or fibers, which could not be achieved by conventional methods of adding fine particles. However, providing fine protrusions on the surface within a range that satisfies the flatness required for molded products such as films and fibers will synergistically enhance the effects of the present invention. The fine particles used include, but are not limited to, external particles and internal particles of calcium carbonate, titanium oxide, kaolin, silica, calcium terephthalate, and the like. Furthermore, additives such as colorants and stabilizers may also be used in the polyester product of the present invention.

[Example] The present invention will be described in detail below with reference to Examples. In addition, the physical properties in Examples were measured as follows.

A: Intrinsic viscosity of polymer 0 This is a value measured at 25°C using chlorophenol as a solvent.

B. Number of foreign substances in polymer The polymer was taken out in the form of a ribbon during discharge, and the number of foreign substances visible to the naked eye was shown on a white paper within a 30×40 cm area of the ribbon.

C. Friction coefficient of film Value measured according to ASTM-D-1894-63 method.

D. Surface roughness of film It was expressed as center line average roughness Ra.

E. Contact angle of film with water The contact angle was measured using a contact angle measuring device "FACE contact angle meter manufactured by Kyowa Interface Science Co., Ltd.".

Examples 1 to 8 100 parts by weight of dimethyl terephthalate, 70 parts by weight of ethylene glycol, 2 parts by weight of 2-octadecy, and 0.03 parts by weight of antimony trioxide were added and a transesterification reaction was carried out in a conventional manner to obtain jq. The product contains 0.04 parts by weight of phosphoric acid trimethyl ester and an average particle size of 0.3μ.
After adding 0.05 parts by weight of calcium carbonate, the temperature was gradually raised and the pressure was reduced, and finally polymerization was carried out under a reduced pressure of 290'CC11yurtH or less. 3 hours 1 from the start of decompression
A polyester composition with an intrinsic viscosity of 0.618 was obtained in 5 minutes.

This polyester was melt-extruded at 280°C to create an unstretched sheet. Then at 80℃ in one direction for 3
．． The film was stretched 5 times, roughly stretched 3.6 times at 110° C. in a direction perpendicular to the previous stretching, and then heat set at 200° C. for 5 seconds to obtain a biaxially stretched film with a thickness of 15 μm. The surface roughness and slipperiness of the film are as shown in Table 1, and the polyester composition of the present invention has a surface roughness Ra of 0.05 or less, which is a desired value for magnetic tape applications in the film field. , it can be seen that it has excellent performance in terms of surface flatness and slipperiness compared to those with a dynamic friction coefficient of 1.0 or less.

Furthermore, since the contact angle with respect to water is 80', it is clear that the polyester has high water repellency.

Further, as shown in Table 1, a biaxially stretched film was obtained in the same manner as in Example 1 except that the amount, timing, and type of the long-chain alkyl group-containing ester-forming compound were changed. It can be seen that the polyester composition of the present invention has excellent surface flatness and slipperiness.

Example 9 Bis-(β-hydroxyethyl) terephthalate was obtained by esterifying 1,100 parts of terephthal and 45 parts of ethylene glycol by a conventional method. To this were added 0.03 parts of antimony trioxide, o and io parts of calcium acetate, 0.045 parts of trimethyl phosphate, and 12.0 parts of 2-octadecyl succinic anhydride. After reacting by stirring and mixing for 30 minutes, insect condensation was carried out by a conventional method, and the intrinsic viscosity was 0.
．． 618 polymer was obtained.

A biaxially stretched film was obtained using the polymer in the same manner as in Example 1. The physical properties are shown in Table 1, and it can be seen that the surface flatness and slipperiness are excellent. Furthermore, the contact angle of the film with water was 79°, indicating that it is highly water repellent.

Comparative Example 1 A biaxially stretched film was obtained in the same manner as in Example 1 except that 2-octadecylsuccinic anhydride was not added. Table 1 shows the physical properties.
Although the surface flatness was good, the slipperiness was poor and blocking occurred when the film was wound.
It was difficult to handle. Further, the contact angle of the film with water was 67°, indicating insufficient water repellency.

Comparative Examples 2 and 3 Polymerization was carried out in the same manner as in Example 1 except that sodium montanate and sorbitan tristearate were added instead of 2-octadecylsuccinic anhydride. When sodium montanate was added, the degree of polymerization did not increase;
The intrinsic viscosity of the polymer after time polymerization was 0.524, it was colored, and many foreign substances were present in the polymer.

In addition, when using sorbitan tristearate,
During the polycondensation reaction, most of the sorbitan tristearate was scattered out of the system, and brown foreign matter was present in the polymer.

As shown in Table 1, a biaxially stretched film obtained from a polymer using these additives in the same manner as in Example 1 showed improvement in slipperiness, but poor surface flatness. I understand. Furthermore, when molding into a film, in Example 1, the film did not break once per 30 minutes, whereas in Comparative Example 2, that is, the polymer to which sodium montanate was added, the film broke 7 times per 30 minutes. That is, in the case of the polymer to which sorbitan tristearate was added, four film tears occurred.

Comparative Example 4 A biaxially stretched film as shown in Table 1 was obtained in the same manner as in Example 1 except that 2-pentyl succinic anhydride was added instead of 2-octadecyl succinic anhydride. It can be seen that in the case of the film to which 2-pentyl succinic anhydride was added, the improvement in slipperiness was insufficient.

Comparative Examples 5 to 6 Biaxially stretched films were obtained in the same manner as in Example 1, except that the amount of 2-octadecylsuccinic anhydride added was changed as shown in Table 1. The physical properties are shown in Table 1, and the amount added is 0.00
In the case of 0.05 parts by weight, the surface flatness was good, but the slipperiness was poor and blocking occurred when the film was wound up, resulting in poor handling. The contact angle of the film with water was also 69°, indicating insufficient water repellency. Further, when the amount added was 50 weights and 1 part, the film frequently broke during stretching, and the film could not be wound up.

(The following is a margin) [Effects of the invention] The present invention adds a specific compound to polyester and causes it to react, thereby eliminating poor ejection, film tearing, and There are no problems such as thread breakage, and when it is made into a film or fiber, it can simultaneously improve slipperiness and surface flatness, and it can also significantly improve surface properties such as water repellency and mold releasability. Therefore, when formed into fibers or films, excellent water repellency can be produced.

The polyester obtained by the present invention has excellent slipperiness and surface flatness, so it is effectively used in fields such as films and fibers, and in particular for magnetic tapes and other products that have strict requirements for surface flatness and slipperiness. Since the surface characteristics have been modified, it can be preferably used for water-repellent materials, graphics such as release paper, and printing materials.

Claims (1)

[Claims] When producing polyester from dicarboxylic acid or its derivative and glycol, 0.001 to 30 parts by weight of an acid anhydride, lactone, and epoxide having an alkyl group having 6 or more carbon atoms is used per 100 parts by weight of the polyester. A method for producing a modified polyester, which comprises adding at least one long-chain alkyl group-containing ester-forming compound.