JPH04100854A - Polyester composition - Google Patents

Abstract

PURPOSE:To prepare the title compsn. giving a film, etc., excellent in slipperiness, transparency, etc., by compounding an arom. polyester with fine particles of a divinylbenzene/ethylvinylbenzene copolymer having specific functional groups. CONSTITUTION:Particles of a divinylbenzene/ethylvinylbenzene copolymer having a mean particle diameter of 0 01-5mum are, e.g. treated with (meth)acrylic acid, etc., to introduce carboxyl groups to the surface each particle of and made alkaline to give particles of a divinylbenzene/ethylvinylbenzene copolymer having alkali metal carboxylate groups. The resulting particles are compounded into a polyester comprising a dibasic acid component mainly consisting of an arom. dibasic acid (e.g. terephthalic acid) and at least one glycol component (e.g. ethylene glycol), giving the title compsn.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a polyester composition, and more specifically, a polyester composition containing divinylbenzene having an average particle size of 0.01 to 5 μm and having an alkali metal salt of a carboxyl group as a functional group. -Relating to a polyester composition containing ethylvinylbenzene copolymer particles.

[Prior Art] Polyester, particularly polyethylene terephthalate, has excellent physical and chemical properties and is therefore widely used as fibers, films, and articles thereof. However, contrary to its excellent properties, undesirable problems occur, such as poor workability due to poor process passability in the molding process to obtain the above-mentioned molded product, or poor slipperiness during handling of the product itself, and a decrease in product value. is also known.

In order to solve these problems, many methods have been proposed to improve the slipperiness of the surface of molded products by incorporating fine particles into polyester to give the surface of molded products appropriate irregularities, and some of these methods have not been put into practical use. ing. For example, inert inorganic particles such as silicon oxide, titanium dioxide, calcium carbonate, talc, and kaolinite, or organic polymers such as benzoguanamine formaldehyde resin, polytetrafluoroethylene-hexafluoropropylene copolymer, and polyphenyl ester resin. There is a method of adding fine particles to a polyester synthesis reaction system (for example, JP-A-55-133431, JP-A-57-125247, etc.).

However, when such particles are added, clarity, an important property of polyester, decreases as the amount added increases. It is known that when formed into a film, transparency is significantly impaired, particularly due to the influence of the refractive index of the particles and polyester and the generation of voids near the surface of the particles due to stretching. Regarding the refractive index of the particles, there are few particles with a refractive index close to that of polyester, especially polyethylene terephthalate, and even if there are particles with a similar refractive index, there are problems such as poor slipperiness.

In addition, some organic polymer fine particles in particular have a refractive index close to that of polyester, but they generally have poor heat resistance. Therefore, it tends to soften during polyester polymerization or melt molding, which causes problems such as poor dispersibility of organic particles in the polymer due to aggregation.

For example, Japanese Patent Publication No. 37-18624 discloses adding a finely divided cation exchange material to polyester, but the amount of crosslinking agent is small and the heat resistance is insufficient. Further examples of cation exchange materials are specified that contain reactive substituents such as sulfonates, phosphonates and carboxylates in the form of metal salts, which improve their affinity for basic dyes. Since the heat resistance of the cation exchange material is insufficient, it aggregates in the polyester to form coarse particles and no effect of improving the affinity of the polyester is observed.

On the other hand, Japanese Patent Publication No. 59-5216 discloses blending into polyester a crosslinked polymer fine powder having a group capable of forming a covalent bond with polyester, such as a functional group such as an ester group, a carboxyl group, or a hydroxyl group. There is. However, in order to covalently bond to polyester, for example, carboxyl groups must be in the acid form (-COOH), and when these particles are added to polyester, the particles tend to aggregate together due to their surface activity. The transparency deteriorates due to the inclusion of coarse particles. In addition, special public service 59-
In Publication No. 5216, pulverization and classification are performed in order to obtain a crosslinked polymer fine powder of a constant particle size, which not only complicates the work but also unavoidably contaminates coarse particles.

In recent years, especially in copying applications such as plate making printing, X-ray photography, microfilm, electrophotography, and diazo photography, which require films with excellent slipperiness and transparency.
It has become necessary to satisfy the mutually exclusive phenomena of slipperiness and transparency to a higher degree. However, the current situation is that the problem has not yet been resolved.

Therefore, the present inventors have conducted intensive studies to improve the drawbacks of the conventional particle addition method described above and to obtain a polyester film with a particularly excellent balance between slipperiness and transparency. It has been found that the objects of the invention can be achieved by using divinylbenzene/ethylvinylbenzene copolymer particles having an alkali metal salt of the group.

[Problems to be Solved by the Invention] An object of the present invention is to contain divinylbenzene/ethylvinylbenzene copolymer particles having a specific functional group, and to achieve smoothness and transparency that could not be achieved with conventional techniques. The objective is to provide an excellent polyester composition.

[Means for Solving the Problems] The object of the present invention is to provide a polyester comprising a bifunctional acid component mainly consisting of an aromatic dicarboxylic acid and at least one glycol component, with an average particle size of 0.01 to 5 μm, This is achieved by a polyester composition containing divinylbenzene/ethylvinylbenzene copolymer particles having an alkali metal salt of a carboxyl group as a functional group.

The difunctional acid component of the polyester of the present invention is mainly an aromatic dicarboxylic acid or an ester-forming derivative thereof, and specifically, terephthalic acid, 2,6-naphthalene dicarboxylic acid, 1,2-bis (2-chlorophenoxy)ethane-4,4'-dicarboxylic acid, its ester-forming derivatives include dimethyl terephthalate, dimethyl 2,6-naphthalenedicarboxylate, 1,2bis(2-chlorophenoxy)ethane-4,4 Examples include dimethyl dicarboxylate, among which terephthalic acid or dimethyl terephthalate is preferred. Examples of glycol components include ethylene glycol, butylene glycol, diethylene glycol, propylene glycol, polyethylene glycol, and 1,4-cyclohexane dimetatool, with ethylene glycol being preferred. In addition to these dicarboxylic acids or their ester-forming derivatives and glycol components, other components may be copolymerized, such as diethylene glycol, propylene glycol, neopentyl glycol, polyalkylene glycol, p-xylylene glycol, , 4-cyclohexane dimetatool, diol components such as 5-sodium sulforesorcin, adipic acid, sebacic acid,
Dicarboxylic acid components such as phthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, and 5-sodium sulfoisophthalic acid, polyfunctional dicarboxylic acid components such as trimellitic acid and pyromellitic acid, and oxydicarboxylic acids such as p-oxyethoxybenzoic acid. Ingredients, etc.

When the dicarboxylic acid component is a dicarboxylic acid, it is subjected to an esterification reaction with a glycol, and when it is a dicarboxylic acid ester, it is subjected to an ester/lz exchange reaction with a glycol, and then polycondensed at high temperature and under reduced pressure to obtain a polyester.

Moreover, polycondensation can also be carried out using the prepolymer itself as a starting material.

The particles of the present invention are divinylbenzene/ethylvinylbenzene copolymer particles, and although there are no particular limitations on the composition ratio, it is preferable that the amount of divinylbenzene in the particles exceeds 50% by weight.

More preferably, it is 54% by weight or more. Among these, it is preferable to use 100% commercially available divinylbenzene to form particles, and in that case, divinylbenzene has a purity of 54%.
The composition is more than % by weight. If the divinylbenzene content is less than 50% by weight, particle aggregation occurs during polyester polymerization or melt molding, so transparency and slipperiness tend to deteriorate.

Further, the divinylbenzene/ethylvinylbenzene copolymer particles of the present invention may contain other components,
Examples include styrene, polystyrene, and diethylbenzene, which is an impurity in commercially available divinylbenzene.

Furthermore, the divinylbenzene/ethylvinylbenzene copolymer particles used in the present invention have a thermal decomposition temperature (
Particles having a heat resistance of 390° C. or higher (10% weight loss temperature) are preferable. Preferably, the thermal decomposition temperature is 400°C or higher, more preferably 410°C or higher. Thermal decomposition temperature is 39
If the temperature is below 0°C, particle aggregation occurs during polyester polymerization or melt molding, resulting in poor transparency and slipperiness.

The divinylbenzene-ethylvinylbenzene copolymer particles used in the present invention preferably have a spherical particle shape and a uniform particle size distribution from the viewpoint of transparency and slipperiness.

That is, the volume shape factor is preferably 0.35 to π/6, more preferably 0.45 or more. [However, the volumetric shape factor f is expressed by the following equation. f=V/D
3. Here, ■ is the particle volume (μm3), D is the maximum diameter of the particle in the projected plane (μm)] For example]
In the method of pulverizing and making fine particles as disclosed in Publication No. 8937, the particle shape is irregular and it is difficult to obtain particles with a uniform particle size distribution. This is undesirable because it blocks the mouth and impairs the transparency, slipperiness, and aesthetics of the product.

As the divinylbenzene/ethylvinylbenzene copolymer particles of the present invention, those obtained by known manufacturing methods can be used. Known manufacturing methods include the following methods, for example, by emulsion polymerization.

(1) Soap-free polymerization method, that is, a method in which polymerization is performed without using an emulsifier or using a very small amount of an emulsifier.

(2) A seed polymerization method in which polymer particles are added to the polymerization system prior to emulsion polymerization and emulsion polymerization is carried out.

(3) A core-shell polymerization method in which a part of the monomer components is emulsion polymerized and the remaining monomers are polymerized within the polymerization system.

(4) Polymerization methods using Nigelstad et al., as disclosed in JP-A-54-97582 and JP-A-54-126288.

(5) A polymerization method that does not use a swelling aid in the method of (4).

In the present invention, in order to improve the affinity with polyester, it is necessary to use divinylbenzene/ethylvinylbenzene copolymer particles having an alkali metal salt of a carboxyl group as a functional group. Examples of the alkali metal salts of carboxyl groups include Na salts, K salts, Li salts, etc. Among them, Na salts of carboxyl groups are preferred because they further improve affinity. The chemical species having a functional group for introducing an alkali metal salt of a carboxyl group may be a monomer or a polymer, and is not particularly limited in type. Among these, methacrylic acid, acrylic acid, or polymers thereof are preferred. Furthermore, the chemical species having a carboxyl group may be copolymerized with a chemical species having no functional group or a chemical species having a functional group other than the carboxyl group. preferable. There are no particular limitations on the method of introducing the alkali metal salt of a carboxyl group, but from the viewpoint of the heat resistance of the particles, particles that will become the base for hypercrosslinking are first manufactured, and then the alkali metal salt of a carboxyl group is added to the surface of the base particle. It is preferable to introduce it.

For example, using a divinylbenzene/ethylvinylbenzene copolymer as a base particle, highly crosslinked particles are produced using divinylbenzene, and then carboxyl groups are introduced onto the particle surface using methacrylic acid. Then, by setting the inside of the particle production system to the alkaline side, -COON is applied to the particle surface.
A functional group a is introduced.

The amount of monomer or polymer for introducing this alkali metal salt of a carboxyl group is 0.00% relative to the base particle.
01 to 20% by weight is preferable, and 0.1 to 10% by weight is more preferable.

The average particle diameter of the divinylbenzene/ethylvinylbenzene copolymer particles used in the present invention must be 0.01 to 5 μm, more preferably 0.05 to 2 μm. If the average particle size is less than 0.01 μm, the slipperiness will decrease when formed into a film.

Furthermore, if the average particle size exceeds 5 μm, the transparency of the film decreases due to the generation of voids and increased scattering on the film surface due to coarse protrusions.

Further, the amount of divinylbenzene/ethylvinylbenzene copolymer particles added to the polyester is preferably 0.
．． 001 to IO weight %, more preferably 0.00
It is 2 to 5% by weight.

When the divinylbenzene/ethylvinylbenzene copolymer particles of the present invention are used, the divinylbenzene/ethylvinylbenzene copolymer particles have a refractive index close to that of polyester,
It has excellent particle size uniformity and has good affinity due to the presence of specific functional groups, so when it is made into a stretched film, a film with excellent transparency can be obtained, and the two mutually exclusive phenomena of slipperiness and transparency can be obtained. can be more highly satisfied.

In addition, divinylbenzene with an average particle size of 0.01 to 5 μm
When using ethylvinylbenzene copolymer particles, the first
As a component, the average particle diameter is 0.01 μm or more and less than 0.1 μm, preferably 0.01 μm or more and less than 0.1 μm. Consisting of a two-component system consisting of one having a low μm or more and less than 0.08 μm, more preferably 0602 μm or more and less than 0.06 μm, and a second component having an average particle size of 0.1 to 5 μm, preferably 0.1 to 2 μm. It is preferable to use divinylbenzene/ethylvinylbenzene copolymer particles because they improve slipperiness. Furthermore, when divinylbenzene/ethylvinylbenzene copolymer particles consisting of two components are dispersed and contained in polyester, the value of the ratio Dw/DN between the weight average diameter D and the number average diameter DN is 1.2.
It is preferably 1.2 or more and 10 or less, more preferably 1.2 or more and 5 or less.

When dispersing divinylbenzene/ethylvinylbenzene copolymer particles consisting of two components in polyester, two types of divinylbenzene/ethylvinylbenzene copolymer particles are produced separately and the resulting particles are mixed. Although they may be dispersed and contained in the polyester, from the viewpoint of workability, cost, and surface flatness, two types of particles are simultaneously manufactured at the manufacturing stage of the divinylbenzene/ethylvinylbenzene copolymer particles, and the particles are dispersed in the polyester. It is more preferable to contain it in a dispersed manner.

In the present invention, divinylbenzene as the second component.
The amount of the ethylvinylbenzene copolymer particles added is 0.0001 to 10% by weight, more preferably 0.001 to 15% by weight, and even more preferably 0.01 to 5% by weight based on the polyester. .

Further, the amount of the divinylbenzene/ethylvinylbenzene copolymer particles added as the first component is 0.01 to 5% by weight, more preferably, based on the divinylbenzene/ethylvinylbenzene copolymer particles as the second component. The content is 0.01 to 3% by weight, more preferably 0.05 to 2% by weight.

Furthermore, the divinylbenzene/ethylvinylbenzene copolymer particles of the first component and the second component may both have an alkali metal salt of a carboxyl group as a functional group,
In particular, it is preferable that the divinylbenzene/ethylvinylbenzene copolymer particles as the second component have an alkali metal salt of a carboxyl group as a functional group.

Furthermore, in order to improve the heat resistance or control the refractive index of the divinylbenzene/ethylvinylbenzene copolymer particles, an inorganic substance such as 5i02 or TiO2 may be coated around the divinylbenzene/ethylvinylbenzene copolymer particles. .

The divinylbenzene/ethylvinylbenzene copolymer particles of the present invention can be added to and mixed with polyester by various known methods. It may be added during the production stage of polyester, or may be added to and mixed with the polymer in a molten state using a -screw extruder, a twin-screw extruder, an extruder with a vent mechanism, or the like. When added at the polyester manufacturing stage, it is particularly preferable to add from before the start of polyester polymerization to during the polymerization reaction from the viewpoint of particle dispersibility. Preferably, the particles are added as a slurry of ethylene glycol in the precursor stage or polycondensation stage before producing the polyester composition. The appropriate slurry concentration is about 0.5 to 20% by weight.

For dispersion in a dispersion medium such as ethylene glycerol or coal, a high-speed dispersion machine, a sand mill, a roll mill, etc. may be used, for example.

In addition, during dispersion, phosphorus atom-containing compounds such as phosphoric acid and sodium hexametaphosphate, nitrogen atom-containing compounds such as tetraethylammonium hydroxide and hydroxylamine, alkali compounds, cations, anions,
It is particularly preferable to use a dispersant such as an amphoteric or nonionic surfactant or a water-soluble polymer, since this further improves the dispersibility of the divinylbenzene/ethylvinylbenzene copolymer particles in the slurry and polymer.

Furthermore, metal compound catalysts of compounds such as lithium, sodium, calcium, magnesium, manganese, zinc, antimony, germanium, and titanium commonly used in the production of polyester, phosphorus compounds as color inhibitors, and divinylbenzene/ethylvinylbenzene copolymer. Inorganic particles and organic polymer fine particles other than the combined particles can also be added as appropriate.

[Example] The present invention will be explained in detail by giving examples below.

Incidentally, each characteristic value of the obtained polyester was measured according to the following method.

(A) Particle size The average particle size was determined by electron micrographs of the particles.
It was determined based on the hard sphere diameter of the particle corresponding to the volume % point. Isohard sphere diameter is the diameter of a sphere that has the same volume as the particle.

In addition, the weight average diameter (D) and number average diameter (DN) can be measured using an image analyzer (e.g. QTM-90).
0: manufactured by Cambridge Instrument) by numerical processing, and the ratio was calculated.

(B) Thermal decomposition of particles using TAS-100 under nitrogen atmosphere, heating rate 2
A thermobalance weight loss curve at 0°C/win was measured. The 10% weight loss temperature was defined as the thermal decomposition temperature.

(C) Intrinsic viscosity of polymer Measured at 25°C using 0-chlorophenol as a solvent.

(D) State of particle dispersion in polymer After cutting the polymer into ultra-thin sections of approximately 0.3 μm using an ultra-thin film production device, the state of particle dispersion in the polymer was observed using a transmission electron microscope.

The dispersion state was determined as follows.

◎Secondary agglomerated particles are hardly observed.

○: Slightly secondary agglomerated particles are present.

Δ: The number of secondary agglomerated particles is large.

×: Most of the particles are secondary agglomerated particles.

(F) Film properties (1) Surface roughness Ra (μm) Shown by stylus surface roughness measurement (cutoff value 0.08 mm, measurement length 0.511110
However, according to J15-B-8801. ) (2) Slip property The coefficient of static friction (μS) and the coefficient of dynamic friction (μd) were measured using a slip tester according to ASTM-D-1894B-63.

(3) Film haze Measured according to ASTM-D-1003-52.

Example 1 A transesterification reaction was carried out by a conventional method using 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol with 0.09 parts by weight of calcium acetate as a catalyst, and the product contained 0.03 parts by weight of antimony trioxide and phosphorus. Thermal decomposition temperature of 0.3 parts by weight of trimethyl acid and 5% by weight of ethylene glycol slurry was 405°C,
Divinylbenzene/ethylvinylbenzene copolymer particles having an average particle size of 0.3 μm and having a sodium salt of a carboxyl group as a functional group [commercially available divinylbenzene 100]
% (divinylbenzene 55%, ethylvinylbenzene 4%
0%, diethylbenzene 5%). Volume shape factor 0
．． 51) 0.05 part by weight was added and polymerized by a conventional method to obtain polyethylene terephthalate having an intrinsic viscosity of 0.615 and a softening point of 260.2°C. As a result of observing the inside of the polymer using a transmission electron microscope, the particles were dispersed in a nearly monodispersed state with little secondary aggregation.

The polymer was melt extruded at 290°C and stretched 3.3 times in the machine direction at 85°C and 365 times in the transverse direction at 95°C. Thereafter, it was heat-set at 205° C. to obtain a two-wheeled stretched film with a thickness of 90 μm. As a result of evaluating the film properties, it was found that both slipperiness and transparency were good (Table 1).

Examples 2 to 7 and Comparative Examples 1 to 3 Examples were prepared by changing the average particle size and the type of functional group of the divinylbenzene/ethylvinylbenzene copolymer particles (all having a volume shape coefficient of 0.51). Similarly to 1, a biaxially oriented film of polyethylene terephthalate was used. When the divinylbenzene/ethylvinylbenzene copolymer particles contained had an average particle diameter and a type of functional group within the range of the present invention, when made into a film, it had excellent slipperiness and transparency.

However, if the average particle size of the divinylbenzene ethylvinylbenzene copolymer particles contained is outside the scope of the present invention, if there is no functional group, or if the functional group is C0OH,
It was not possible to satisfy both slipperiness and transparency (Comparative Examples 1 to 3).

Example 8.9 The divinylbenzene/ethylvinylbenzene copolymer particles (both have volume shape coefficients of 0.51) were made into a two-component system, and a biaxially oriented film of polyethylene terephthalate was prepared in the same manner as in Example 1. . Here, the D w / D N ratio of the system of Example 8 is 3.8, and the system of Example 9 is 4.0.
It is. When the contained divinylbenzene/ethylvinylbenzene copolymer particles were made into a two-component system, when made into a film, the slipperiness was improved and the transparency was also excellent.

Comparative Example 4.5.6 Other polymer particles such as styrene and
Using divinylbenzene copolymer particles, styrene/acrylic copolymer particles, and colloidal silica as inorganic particles,
A biaxially oriented polyethylene terephthalate film was prepared in the same manner as in Example 1. None of them could satisfy both slipperiness and transparency.

(The following is a blank space) [Effects of the Invention] Since the polyester of the present invention contains divinylbenzene/ethylvinylbenzene copolymer particles having a specific functional group, it exhibits the following excellent effects.

(1) Since the divinylbenzene-ethylvinylbenzene copolymer particles of the present invention are highly crosslinked, the particles have improved heat resistance and can be uniformly dispersed in the polymer. Therefore, it can be easily molded by a normal molding method, and the obtained fibers, films, or molded products have excellent mutual sliding properties, and troubles such as clogging of the molding machine, thread breakage, and film tearing do not occur.

(2) The particles of the present invention have a refractive index close to that of the polyester of the present invention, and have excellent particle size uniformity.In addition, since they have specific functional groups, they have improved affinity with polyester, making them suitable for films. In this case, a film with good transparency and slipperiness can be obtained.Such a film is suitable for photography, plate making, and the like.

(3) Since the particles of the present invention have excellent affinity with polyester, when made into a film, there are few voids and excellent abrasion resistance and electrical properties. Such a film is suitable for magnetic tape applications and capacitor applications.

Claims (1)

[Claims] Divinylbenzene/ethylvinyl polyester consisting of a bifunctional acid component mainly consisting of an aromatic dicarboxylic acid and at least one glycol component has an average particle size of 0.01 to 5 μm and has an alkali metal salt of a carboxyl group as a functional group. A polyester composition containing benzene copolymer particles.