JPH0797438A - Ethylene glycol dispersion of crystalline calcium carbonate and polyester composition - Google Patents

Abstract

PURPOSE:To provide the title dispersion improved in lubricity, surface smoothness, abrasion resistance and segregation resistance by adding a phosphorus compound and a carboxylic acid compound or a coupling agent to an ethylene glycol dispersion of crystalline CaCO3. CONSTITUTION:Quick lime is dispersed in a medium comprising at least 80% ethylene glycol, and the dispersion is carbonated by blowing a gas containing carbon dioxide thereinto to obtain an ethylene glycol dispersion of crystalline CaCO3. At least one member selected from among 0.1-20 pts.wt. (in terms of phosphorus), per 100 pts.wt. CaCO3, phosphorus compound, 0.5-30 pts.wt. carboxylic acid compound and 0.1-30 pts.wt. coupling agent is added to this dispersion to obtain an ethylene glycol dispersion of crystalline CaCO3. This dispersion and an aromatic dicarboxylic acid are subjected to polycondensation to obtain a polyester composition.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an ethylene glycol dispersion of crystalline calcium carbonate and a polyester composition. More specifically, the surface of crystalline calcium carbonate is coated with various phosphorus compounds, carboxylic acid compounds or coupling agents. The present invention relates to an ethylene glycol dispersion of crystalline calcium carbonate and a polyester composition, the dispersibility of which is significantly improved in polyester.

[0002]

2. Description of the Related Art Polyesters, especially polyethylene terephthalate, have excellent physical and chemical properties and are widely used as films, fibers and various molded articles. Among them, in the film field, magnetic tapes such as audio tapes and video tapes, packaging, agricultural, O
Various uses such as for HP are known, and in the fiber field, it is used in large quantities for industrial purposes such as tire cords, V-belts, and rubber reinforcing fibers typified by conveyor belts, or for various clothing. ing. However,
Despite these excellent properties, the unfavorable problems such as poor workability and reduced commercial value due to poor slipperiness in the molding process for obtaining the above-mentioned molded product and the product itself, scrap scraps and fallen objects Have a

Conventionally, as a method of lowering the coefficient of friction, which is a measure of poor slipperiness, it has been usual to produce or blend fine particles in polyester to impart appropriate protrusions to the film surface to improve slipperiness. It is being appreciated. Examples of such fine particles include fine particles precipitated from a catalyst residue during the production of polyester, and inorganic fine particles insoluble in polyester such as calcium carbonate, titanium dioxide, silica, talc, and carion. However, the method of incorporating these fine particles, on the other hand, impairs the surface smoothness of the film. In addition, the former fine particles deposited inside are difficult to control the amount and diameter of the particles and are easily broken in the stretching process, and therefore satisfactory effects in running property and abrasion resistance are not obtained. Further, when the latter inorganic fine particles are added, the affinity between the fine particles and the polyester is not always sufficient, and voids are generated around the particles in the stretching step, causing a problem that white powder is generated due to damage to the film or fiber or loss of the fine particles. Is causing. Especially with regard to magnetic tape, not only slipperiness but also recent high quality,
In order to meet the demands for downsizing and long-time recording, a film with a smooth surface and a thin thickness is required, and surface smoothness, abrasion resistance, and drop resistance are important characteristics.

Various attempts have been made to obtain a film satisfying all these characteristics. For example, JP-A-5
A method of using a specific dispersant when preparing a glycol slurry disclosed in JP-A-0-1144 and JP-A-51-68695, and a glycol slurry disclosed in JP-A-52-78953. Physical dispersion method for imparting ultrasonic vibrations when moving, JP-A-59-179555
Japanese Patent Laid-Open No. 62-232431, a method of blending two kinds of particles having a specific particle size distribution ratio when producing a polyester film, and a specific particle size when producing a polyester disclosed in Japanese Patent Laid-Open No. 62-232431. Examples include a method of blending fine particles containing an element having a distribution and a dispersing function.

Particularly with regard to the improvement of the affinity between the inorganic fine particles and the polyester, the surface treatment with the polyacrylic acid-based polymer disclosed in JP-A-63-128031, JP-A-64-43537 and JP-A-43-43537 are disclosed. 4-298538
The surface treatment with the coupling agent disclosed in Japanese Patent Laid-Open Publication No. 1989-242, and the like can be mentioned. On the other hand, as an example in which the chemical composition of the fine particles themselves is changed, 5 to 40 weight parts of calcium carbonate containing a phosphorus atom disclosed in JP-A-63-234039 and calcium element in JP-A-4-224861 are disclosed. % Of the wet method silica particles. Also,
As an example in which the shape of the fine particles themselves is modified, an inert fine particle having two protrusions on the surface of JP-A-64-48835, and a core on the surface of a particle serving as a core of JP-A-3-70768 are disclosed. Of composite particles coated with fine particles having an average diameter of 1/10 or less of the above, secondary particles having an average particle diameter of 0.03 to 3 μm in which the primary particles of JP-B-4-25857 are combined
Examples thereof include silicon oxide particles having a surface area of 250 m ² / g or more as determined by the ET method.

However, none of the methods has achieved satisfactory effects in terms of slipperiness, surface smoothness, wear resistance, and drop resistance. In recent years, it has been said that it is extremely difficult to obtain a film having such characteristics even though the demand for a film having these contradictory surface characteristics has further increased.

[0007]

In view of the above circumstances, the inventors of the present invention have conducted extensive studies from the stage of synthesizing inorganic fine particles in order to solve the above-mentioned drawbacks of the prior art, and as a lubricity improver for films and fibers. Was successful in synthesizing crystalline calcium carbonate having a suitable spherical shape and a sharp particle size distribution and having surface protrusions effective in preventing falling off by carrying out a carbonation reaction in an ethylene glycol system (Japanese Patent Application No. 4-17694).
8). However, this crystalline calcium carbonate has a strong tendency to aggregate in polyester, and the only way to eliminate this aggregation is to rely on a physical method, that is, stirring.
The present inventors have further conducted intensive studies in order to solve this unique aggregation of crystalline calcium carbonate by a chemical method, and have added a phosphorus compound, a carboxylic acid compound or a coupling agent to the ethylene glycol dispersion of the crystalline calcium carbonate. The present invention was achieved by adding or by including the surface of the crystalline calcium carbonate in the polyester composition in a state of being coated with a phosphorus compound, a carboxylic acid compound or a coupling agent.

That is, an object of the present invention is to provide an ethylene glycol dispersion of crystalline calcium carbonate having good dispersibility in polyester and a polyester composition in which crystalline calcium carbonate is uniformly dispersed.

[0009]

Means and Actions for Solving the Problems The present invention addresses the above problems by containing at least one of a phosphorus compound, a carboxylic acid compound and a coupling agent in an ethylene glycol dispersion of crystalline calcium carbonate. It was solved by a characteristic ethylene glycolome dispersion. Further, the present invention has been solved by a polyester composition characterized by containing the crystalline calcium carbonate coated with at least one of a phosphorus compound, a carboxylic acid compound and a coupling agent.

In the present invention, the polyester is a polyester obtained by a polycondensation reaction with an aromatic dicarboxylic acid as a main acid component and a glycol component. Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, diphenylethanedicarboxylic acid and the like. Examples of the glycol component include ethylene glycol, diethylene glycol, propylene glycol, tetramethylene glycol and the like.
The most representative polyester is mainly composed of polyethylene terephthalate obtained by polycondensation reaction of terephthalic acid and ethylene glycol as main monomer components.

The calcium carbonate fine particles having the above characteristics of the present invention are crystalline calcium carbonate prepared by carbonation in an ethylene glycol system. Since the crystalline calcium carbonate prepared by this method is obtained by crystallization in an ethylene glycol system, it has an advantage that it can be added as it is in the production process of polyester.

Further, in the present invention, the phosphorus compound includes various inorganic and organic phosphorus compounds. Examples of the inorganic phosphorus compound include metaphosphoric acid, pyrophosphoric acid, orthophosphoric acid and the like. Examples of the organic phosphorus compound include phosphite, phosphoric acid ester, acidic phosphoric acid ester, and phosphonic acid ester. Specifically, trimethyl phosphite, triethyl phosphite, trimethyl phosphate, triethyl phosphate, Examples thereof include triphenyl phosphate, acidic phosphoric acid methyl ester, methylsulfonic acid methyl ester, phenylphosphonic acid ethyl ester, and benzylphosphonic acid phenyl ester.

The carboxylic acid compound includes a carboxylic acid which is an organic compound having a carboxyl group and its derivative, and a compound having both a carboxyl group and a functional group other than the carboxyl group.

Examples of the carboxylic acid include various fatty acids, phthalic acid, terephthalic acid, isophthalic acid, acrylic acid, itaconic acid, maleic anhydride and the like. Examples of the carboxylic acid derivative include salts and esters of alkali metals, alkaline earth metals and ammonium substituted with hydrogen radicals of carboxyl groups, and acyl compounds substituted with hydroxyl groups. Specific examples include sodium terephthalate, sodium polyacrylate, ammonium polyacrylate, sodium polyisobutylene maleate, and acrylic acid ester.

Examples of the compound having both a carboxyl group and a functional group other than it include hydroxy acid, ketonic acid, aldehyde acid, phenolic acid, amino acid, halogencarboxylic acid, and the derivatives thereof are also effective.

Further, polymers and copolymers of the above carboxylic acid compounds are also effective.

The coupling agent is not particularly limited as long as it is a substance having a non-hydrolyzable organic functional group having a substituent that binds to one or more organic materials in the same molecule. Three types of silane-based, titanate-based, and aluminum-based are commonly known.

For example, as the silane coupling agent,
Vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxycypropyltrimethoxysilane, β- (3,4epoxycyclohexyl) ethyltrimethoxysilane, γ-gly Sidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-
Aminopropyltriethoxysilane, N-phenyl-γ
-Aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane and the like can be mentioned.

Examples of titanate coupling agents include isopropyltriisostearoyl titanate, isopropyltri-N-dodecylbenzenesulfonyl titanate, isopropyltris (dioctylphosphite) titanate, tetraisopropylbis (dioctylphosphite) titanate, tetraoctyl. Bis (ditridecyl phosphite) titanate, tetra (2,2-
Diallyloxymethyl-1-butyl) bis (di-tridecyl) phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, isopropyl tri (N-aminoethyl-aminoethyl) titanate, etc. are the aluminum coupling agents. , Acetoalkoxy aluminum diisopropylate and the like.

The ethylene glycol dispersion of crystalline calcium carbonate having good dispersibility in the polyester of the present invention is obtained by adding the above phosphorus compound, carboxylic acid compound or coupling agent to the above ethylene glycol dispersion of crystalline calcium carbonate. Obtained by mixing. As for this mixing method, for those which are soluble in ethylene glycol or which have good compatibility, sufficient effects can be exhibited by a simple mixing operation such as addition as it is and stirring. However, for those that do not dissolve in ethylene glycol or have poor compatibility, add them by dissolving them in a solvent that dissolves easily in advance, or use a variety of surfactants to homogenize them in an ethylene glycol dispersion of crystalline calcium carbonate. It is necessary to mix in.

The polyester composition in which the crystalline calcium carbonate is uniformly dispersed according to the present invention is an ethylene glycol dispersion of crystalline calcium carbonate obtained by adding the phosphorus compound, the carboxylic acid compound or the coupling agent described above. It can also be obtained by utilizing, but crystalline calcium carbonate and phosphorus compound, at any stage of the polyester manufacturing process,
It can also be obtained by separately adding a carboxylic acid compound or a coupling agent. Further, the crystalline calcium carbonate and the phosphorus compound, the carboxylic acid compound or the coupling agent may be added from the initial stage of the esterification or transesterification reaction of the dicarboxylic acid component and glycol until the reaction is completed and a prepolymer is obtained. Is preferably added at the stage of or the initial stage of polycondensation of the prepolymer, and more preferably, the crystalline calcium carbonate and the phosphorus compound, the carboxylic acid compound or the coupling agent are added at the same time or the crystalline calcium carbonate is added slightly later. It is most effective to do.

The amount of phosphorus compound added in these cases is 0.1 to 20 parts by weight, preferably 0.3 to 1 in terms of phosphorus atom based on 100 parts by weight of crystalline calcium carbonate.
0 parts by weight. If the amount added is less than 0.1 parts by weight, the dispersibility of the crystalline calcium carbonate is lowered, and the morphological characteristics of the crystalline calcium carbonate cannot be fully utilized. Further, if it exceeds 20 parts by weight, not only is it economically disadvantageous, but the polymerization time becomes long. In addition, there are problems such as a decrease in the softening point of the polymer, breakage of the film in the film forming process, and sticking to the roll.

The amount of carboxylic acid compound added is in the range of 0.5 to 30 parts by weight, preferably 1.0 to 20 parts by weight, based on 100 parts by weight of crystalline calcium carbonate. If the addition amount is less than 0.5 parts by weight, the dispersibility of the crystalline calcium carbonate is reduced, and the morphological characteristics of the crystalline calcium carbonate cannot be fully utilized, as in the case of adding the phosphorus compound. Further, if it exceeds 30 parts by weight, not only is it economically disadvantageous, but sometimes the polymer is adversely affected.

The amount of the coupling agent added is 0.1 to 100 parts by weight of crystalline calcium carbonate.
It is in the range of 30 parts by weight, preferably 0.5 to 20 parts by weight. If the addition amount is less than 0.1 parts by weight, the dispersibility of the crystalline calcium carbonate is lowered, the morphological characteristics of the crystalline calcium carbonate cannot be fully utilized, and if it exceeds 30 parts by weight, it is economically disadvantageous. Not only that, but it sometimes has various adverse effects on the polymer, as in the case of adding the carboxylic acid compound.

The ethylene glycol dispersion of crystalline calcium carbonate containing a phosphorus compound, a carboxylic acid compound or a coupling agent according to the present invention has a strong tendency to agglomerate in the polyester by physical means. It is possible to disperse significantly without depending on the above, and the crystalline calcium carbonate is uniformly dispersed in the polyester composition obtained by coating a phosphorus compound, a carboxylic acid compound or a coupling agent. It has a spherical shape and a sharp particle size distribution.
It is possible to make the most of the feature of having surface protrusions that are effective in preventing falling. As a result, the polyester composition of the present invention not only improves slipperiness and surface smoothness when formed into a film or fiber, but also has voids due to stretching during forming, which has been a problem when conventional inorganic fine particles are added. It is possible to prevent the generation of white powder and the deterioration of wear resistance due to the falling of particles, which is considered to be caused by the occurrence of
It is possible to solve problems such as reduction in product value. In addition, as long as the effect of the inorganic fine particles of the present invention is not impaired, it may be used in combination with inorganic or organic fine particles insoluble in polyester, or fine particles precipitated in the reaction system during the production of polyester. Further, the combined use of a dispersant of a phosphoric acid type, a carboxylic acid type, or a coupling agent type is also effective in enhancing the dispersing effect.

That is, an ethylene glycol dispersion of crystalline calcium carbonate containing a phosphorus compound, a carboxylic acid compound or a coupling agent prepared by the above method is used, or the crystalline substance is used in the production process of polyester. The crystalline calcium carbonate can be uniformly dispersed in the polyester only by coating the surface of the calcium carbonate with the phosphorus compound, the carboxylic acid compound or the coupling agent, and the problem of the present invention can be solved. Furthermore, the polyester composition thus obtained can provide a film or fiber excellent in slipperiness, surface smoothness, abrasion resistance and drop resistance.

[0027]

EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples.

Preparation of Crystalline Calcium Carbonate 670 g of quicklime powder was added to 4 kg of ethylene glycol, and after stirring, the mixture was transferred to a stainless steel reactor having a volume of 30 liters, and 15 kg of ethylene glycol was further added to prepare a raw material slurry. At this time, the temperature of the slurry is 34
C., pH was 12.2 and conductivity was 3.8 mS / cm. A mixed gas with air having a carbon dioxide gas concentration of 30% by volume was introduced into this raw material slurry at a rate of 66.7 liters / minute. During the carbonation process, the pH showed an almost constant value, but the conductivity gradually decreased to 0.8 mS / cm, and after 40 minutes, the p
When H was 7.2, the slurry gelled. The temperature at that time is 4
It was 4 ° C. The entire amount of this gel was heated to 60 ° C. Two
The gel almost collapsed in ~ 3 hours and reslurried again.

A crystalline calcium carbonate X was prepared by concentrating a slurry of calcium carbonate obtained by allowing it to stand overnight for a solid concentration of 20% by weight. A part of this slurry was filtered, washed with methanol, and dried at 110 ° C. The X-ray diffraction result of the powder matched the pattern of calcite. Also, T
The primary particle diameter observed by EM was about 0.01 μm, and the average particle diameter of the secondary particles was 0.60 μm.

Various phosphorus compounds, carboxylic acid compounds or coupling agents were added to and mixed with the ethylene glycol dispersion of crystalline calcium carbonate prepared in Examples 1 to 21 to prepare crystalline carbonate containing these substances. An ethylene glycol dispersion of calcium was prepared. A typical example is shown below. In addition, the addition amount is CaCO ₃ converted into phosphorus atoms in Examples 1 to 9.
In parts by weight, for Examples 10 to 15, the pure content of the carboxylic acid compound is expressed in parts by weight with respect to CaCO _{3, and} for Examples 16 to 21, the pure content of the coupling agent is in parts by weight with respect to CaCO ₃ . It is a representation.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

[Table 3]

Comparative Examples 1 to 14 Various phosphorus compounds were converted into phosphorus atoms in the ethylene glycol dispersions of crystalline calcium carbonate prepared in the above manner to give a value of 0.
03 parts by weight / CaCO ₃ , a carboxylic acid compound in a pure content of 0.3 parts by weight / CaCO ₃ or a coupling agent in a pure content of 0.05 parts by weight / CaCO ₃ added and mixed, and a crystal containing these substances A dispersion of calcium carbonate in ethylene glycol was prepared. They are shown below.

[0035]

[Table 4]

[0036]

[Table 5]

[0037]

[Table 6]

Example 22 100 parts by weight of dimethyl terephthalate as an acid component, 70 parts by weight of ethylene glycol as a glycol component,
After transesterification of 0.035 parts by weight of manganese acetate tetrahydrate as a catalyst in a usual manner, 0.03 parts by weight of trimethyl phosphate and antimony trioxide were added, respectively, and crystalline calcium carbonate A was added in a solid content. 0.3 wt% was added and polycondensed to obtain a polyester containing crystalline calcium carbonate having an intrinsic viscosity of 0.62.

Examples 23 to 42 The same as Example 22 except that crystalline calcium carbonates B to U were used instead of crystalline calcium carbonate A.

Comparative Examples 15-29 Example 22 except that crystalline calcium carbonate X, b, d, e, h, j, l, m, o, p-u was used in place of crystalline calcium carbonate A. Is the same as.

Examples 43 to 56 100 parts by weight of dimethyl terephthalate as an acid component, 70 parts by weight of ethylene glycol as a glycol component,
After transesterification of 0.035 parts by weight of manganese acetate tetrahydrate as a catalyst in a conventional manner, 0.03 parts by weight of trimethyl phosphate and 0.03 part by weight of antimony trioxide were added respectively to carry out polycondensation to obtain an intrinsic viscosity of 0. 62 polyesters containing crystalline calcium carbonate were obtained. The phosphorus compound, the carboxylic acid compound and the amount of the coupling agent and the timing of addition at this time,
The timing of addition of the crystalline calcium carbonate is as follows.

[0042]

[Table 7]

[0043]

[Table 8]

[0044]

[Table 9]

Comparative Examples 30 to 34 The same as Examples 43 to 47 except that the addition amount of the phosphorus compound was converted into phosphorus atoms to be 0.03 parts by weight / CaCO ₃ .

Comparative Examples 35-39 Addition amount of carboxylic acid compound is 0.3 parts by weight / Ca
The same as Examples 48 to 52 except that CO ₃ was used.

Comparative Examples 40 to 43 The coupling agent was added in an amount of 0.05 parts by weight of pure / Ca.
It is the same as Examples 53 to 56 except that CO ₃ was used.

The above Examples 22 to 56 and Comparative Examples 15 to 4
As a result of observing the polyester produced in Example 3 under an optical microscope at a magnification of 400 times, all the particles were dispersed to the extent that they were indistinguishable in the examples, while 5 to 20 in the comparative examples.
Aggregated particles of μm were observed throughout. From this, it is clear that the effects of the phosphorus compound, the carboxylic acid compound and the coupling agent are remarkable.

[0049]

The ethylene glycol dispersion of crystalline calcium carbonate containing the phosphorus compound, the carboxylic acid compound or the coupling agent of the present invention is a crystalline calcium carbonate which has a strong tendency to aggregate in polyester. It can be completely dispersed in polyester without resorting to means. The crystalline calcium carbonate coated with a phosphorus compound, a carboxylic acid compound or a coupling agent can be easily dispersed in the polyester composition. The polyester composition in which the crystalline calcium carbonate thus obtained is uniformly dispersed is characterized in that the crystalline calcium carbonate has a spherical shape and a sharp particle size distribution, and that it has surface protrusions effective for preventing falling off. You can make the most of it. As a result, the polyester composition not only improves the slipperiness and surface smoothness when formed into a film or fiber, but also causes voids due to stretching during forming, which has been a problem when conventional inorganic fine particles are added. It is possible to prevent the generation of white powder and the decrease in abrasion resistance, which are considered to be caused by the drop of particles, and it is possible to solve problems such as deterioration of workability and decrease of commercial value. Especially when used as a base film for magnetic tape, it exhibits excellent effects.

[Brief description of drawings]

FIG. 1 is a 400 × optical micrograph showing a dispersed state of particles of crystalline calcium carbonate in the polyester obtained in Example 28.

FIG. 2 is a 400 × optical micrograph showing a dispersed state of particles of crystalline calcium carbonate in the polyester obtained in Comparative Example 15.

Claims (2)

[Claims] 1. An ethylene glycol dispersion of crystalline calcium carbonate produced by a carbonation reaction in a medium system containing 80% or more of ethylene glycol, wherein a phosphorus compound, a carboxylic acid compound or a coupling is present in the dispersion. An ethylene glycol dispersion of crystalline calcium carbonate containing at least one of the agents. 2. A polyester containing crystalline calcium carbonate produced by a carbonation reaction in a medium system containing 80% or more of ethylene glycol, wherein the surface of the crystalline calcium carbonate is a phosphorus compound, a carboxylic acid compound or A polyester composition, which is coated with at least any one of coupling agents.