CN100558817C - thermoplastic resin composition - Google Patents

Abstract

The invention provides the thermoplastic resin composition of containing metallic soap and thermoplastic resin.The metallic soap that is contained in the said composition reacts the metal-salt of fatty acid alkali compound salt and divalent and obtains in the aqueous solution; Described fatty acid alkali compound salt is to be 1 mole in 6～24 lipid acid with respect to carbonatoms, and the alkali cpd that makes 1 valency reacts with 0.90 mole～0.99 mole ratio and obtains.In the composition, with respect to these thermoplastic resin 100 mass parts, the content of this metallic soap is 0.01 mass parts～10 mass parts.Said composition is excellence aspect pigment, weighting agent etc. dispersed, and the molecular weight of resin reduces less.

Description

thermoplastic resin composition

technical field

The present invention relates to a thermoplastic resin composition comprising a metal soap and a thermoplastic resin.

Background technique

In the past, additives for thermoplastic resins have been used to improve mold release properties, prevent fusion of resins and molding machines, etc. during resin molding, or to improve the dispersibility of pigments and fillers in resins. For example, according to Ester compounds, amide compounds, metal soaps, silicone compounds and the like are used for the above-mentioned purpose.

Among these additives, metal soaps or silicone compounds are used to improve the dispersibility of pigments or fillers in resins. For example, Japanese Unexamined Patent Publication No. 2003-155405 discloses a titanium oxide dispersion method using polyorganosiloxane.

However, if metal soaps are used together with phenolic antioxidants (for example, 3,5-di-tert-butyl-4-hydroxytoluene, etc.) widely used in thermoplastic resins, the antioxidants will turn yellow and color the resins. Phosphorus antioxidants (for example, triphenyl phosphate, etc.) are used together, and there are problems such as loss of antioxidant capacity. In addition, when metal soap is dispersed when preparing molded articles of polyester resins such as polyethylene terephthalate or polycarbonate, the molecular weight of the resin is reduced, which is one of the causes, and the strength of the resin molded article may decrease. question.

With regard to the silicone compound, there is also a problem that the silicone compound released on the surface of the obtained molded article floats out.

As mentioned above, when using existing additives, it is difficult to disperse pigments or fill in thermoplastic resins without causing problems such as coloring of antioxidants, reduction of antioxidant effects, reduction of molecular weight of resin, and floating of additives on the surface of molded products. agent.

Contents of the invention

The object of the present invention is to provide excellent dispersibility of pigments, fillers, etc., even if antioxidants are contained, the coloring of the resin due to the yellowing of the antioxidants and the reduction of the antioxidant effect rarely occur, and the molecular weight of the resin is reduced. Less thermoplastic resin composition.

The thermoplastic resin composition of the present invention contains a metal soap and a thermoplastic resin. The metal soap is obtained by reacting a fatty acid alkali compound salt and a divalent metal salt in an aqueous solution; the fatty acid alkali compound salt is obtained by making the carbon number It is obtained by reacting a fatty acid of 6 to 24 and a monovalent alkali compound at a ratio of 1 mole: 0.90 to 0.99 moles, and the content of the metal soap is 0.01 to 10 parts by mass relative to 100 parts by mass of the thermoplastic resin .

In a preferred embodiment, the metal constituting the metal soap is calcium or magnesium.

In a preferred embodiment, the thermoplastic resin composition further contains an ester of pentaerythritol and a monovalent saturated fatty acid having 14 to 24 carbon atoms in a ratio of 0.001 to 5 parts by mass based on 100 parts by mass of the thermoplastic resin. compound (hereinafter sometimes referred to as pentaerythritol ester compound).

In a preferred embodiment, the above-mentioned ester compound has an acid value of 5.0 or less and a hydroxyl value of 20.0 or less.

In a preferable embodiment, the said thermoplastic resin is a polyester resin.

The thermoplastic resin composition of the present invention containing a metal soap and a thermoplastic resin has excellent dispersibility of pigments, fillers, etc., and is less prone to decrease in the molecular weight of the resin. Even if the thermoplastic resin composition of the present invention contains an antioxidant, the antioxidant effect is not hindered, and especially when a phenolic antioxidant is contained, coloring is less likely to occur in the resin than conventional thermoplastic resin compositions. When the thermoplastic resin composition further contains a pentaerythritol ester compound, the lubricity at the time of heat-melting the mixture containing the components of the composition is improved.

Detailed ways

The thermoplastic resin composition of the present invention contains a metal soap, a thermoplastic resin, and if necessary, a pentaerythritol ester compound, additives, and the like. They are described in turn below.

(1) Metal soap

The metal soap used in the present invention is produced by a metathesis method in which a fatty acid alkali compound salt and a divalent metal salt are reacted. The metal soap is characterized in that it is obtained by reacting a fatty acid alkali compound salt and a divalent metal salt in an aqueous solution; It is obtained by reacting the base compound at a ratio of 1 mole: 0.90 to 0.99 moles.

The fatty acid used as a raw material of the fatty acid alkali compound salt is not particularly limited as long as it is a fatty acid having 6 to 24 carbon atoms. That is, any of natural fatty acid and synthetic fatty acid may be used, any of saturated fatty acid and unsaturated fatty acid may be used, and any of linear and branched fatty acids may be used. Further, the fatty acid structure may contain hydroxyl groups, aldehyde groups, epoxy groups and the like. Straight-chain fatty acids having 10 to 22 carbon atoms are preferred. When the number of carbon atoms is less than 6, the effect as a dispersant of the metal soap obtained cannot be obtained, and fatty acids having more than 24 carbon atoms are difficult to obtain industrially. These fatty acids can be used individually or in combination of at least 2 types.

Examples of the aforementioned fatty acids include caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, myristoleic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. , arachidic acid, behenic acid, erucic acid, hydroxystearic acid, montanic acid, isostearic acid, 2-ethylhexanoic acid and epoxystearic acid.

Examples of monovalent base compounds used as raw materials for fatty acid base compound salts include hydroxides of alkali metals (sodium, potassium, etc.); ammonia, and amines such as monoethanolamine, diethanolamine, and triethanolamine. Hydroxides of alkali metals such as sodium and potassium are preferable from the viewpoint of high solubility in water when forming a fatty acid alkali compound salt.

The fatty acid alkali compound salt can be obtained by reacting the above-mentioned fatty acid and the above-mentioned monovalent alkali compound at a ratio of fatty acid: monovalent alkali compound = 1 mole: 0.90 to 0.99 moles, preferably 1 mole: 0.95 to 0.98 moles. substance. If the monovalent base compound is less than 0.90 mol or exceeds 0.99 mol with respect to 1 mol of fatty acid, the metal soap prepared from the fatty acid base compound salt obtained by the reaction may not be able to obtain the desired resin moldings. In particular, when a metal soap is prepared using a fatty acid alkali compound salt obtained by reacting a monovalent alkali compound in an amount exceeding 0.99 mol with respect to 1 mole of the fatty acid, and the metal soap is added to a thermoplastic resin for molding When , the molecular weight of the resin decreases; or when the thermoplastic resin composition contains an antioxidant, the antioxidant effect decreases and the resin is colored.

The fatty acid alkali compound salt used in the present invention is a monovalent alkali compound and a fatty acid in the above-mentioned ratio, generally at or above the melting point of the fatty acid and at a temperature at which the fatty acid does not decompose, preferably at 100° C. or below, more preferably It is preferably obtained by reacting at 50°C to 100°C, more preferably at 80°C to 95°C.

The metal soap used in the present invention is obtained by reacting a fatty acid alkali compound salt and a divalent metal salt in an aqueous solution. The aforementioned divalent metal salt is specifically a salt of a divalent inorganic metal and an inorganic acid or an organic acid. Examples of the divalent inorganic metal include alkaline earth metals such as magnesium, calcium, and barium; titanium, zinc, iron, manganese, cadmium, mercury, zirconium, lead, copper, cobalt, and nickel. Among these, calcium, magnesium, barium, and zinc are preferred because they are less colored and decomposed by heating and are easily industrially available. In view of pigment dispersibility, calcium or magnesium is particularly preferable.

As a divalent metal salt, calcium chloride, calcium acetate, magnesium chloride, magnesium sulfate, copper sulfate, barium chloride, zinc chloride, zinc sulfate etc. are mentioned, for example. In particular, chlorides, sulfates, and nitrates such as calcium and magnesium are preferable because they have good solubility in water and react with carboxylates efficiently.

Specifically, the above reaction is carried out by separately preparing an aqueous solution containing a divalent metal salt and an aqueous solution containing a fatty acid alkali compound salt, and then mixing them. For example, by dripping an aqueous solution containing a divalent metal salt in an aqueous solution containing a fatty acid alkali compound salt; adding dropwise an aqueous solution containing a fatty acid alkali compound salt in an aqueous solution containing a divalent metal salt; or adding it dropwise to a reaction tank at the same time proceed in the middle.

The concentration of the fatty acid alkali compound salt when preparing the metal soap is usually 1% by mass to 20% by mass in view of the productivity of the metal soap and the handleability of the aqueous solution containing the fatty acid alkali compound salt or the resulting metal soap slurry. %, preferably 5% by mass to 15% by mass. When the fatty acid alkali compound salt concentration is less than 1% by mass, the yield of the metal soap is low, which is not practically preferable. When it exceeds 20% by mass, the aqueous solution containing the fatty acid alkali compound salt or the viscosity of the obtained metal soap slurry increases, making it difficult to perform a uniform reaction. In addition, the concentration of the divalent metal salt in the solution containing the divalent metal salt is generally 1 to 1 in terms of the productivity of the metal soap and the handleability of the aqueous solution containing the fatty acid alkali compound salt or the obtained metal soap slurry. % by mass to 50% by mass, preferably 10% by mass to 40% by mass.

The reaction between the fatty acid base compound salt and the divalent metal salt is preferably performed at a ratio of 0.45 mol to 0.7 mol of the divalent metal salt to 1 mol of the monovalent base compound used to obtain the fatty acid base compound salt. More preferably, the ratio of the divalent metal salt is 0.49 mol to 0.6 mol, and still more preferably, the ratio is 0.49 mol to 0.55 mol. When the divalent metal salt is outside the range of 0.45 mol to 0.7 mol, if the obtained metal soap is added to a thermoplastic resin for molding, the molecular weight of the obtained resin may decrease, and if an antioxidant is contained, it may cause antioxidation. Defective problems such as reduced oxidation effect and resin coloring.

The reaction between the fatty acid alkali compound salt and the divalent metal salt is carried out under temperature conditions usually performed by those skilled in the art in consideration of the solubility of the fatty acid alkali compound salt. It is preferably 50°C to 100°C, more preferably 70°C to 95°C.

The metal soap slurry was obtained by the above method. The metal soap slurry can be left untreated, or the solvent can be separated by a centrifugal dehydrator, filter press, vacuum rotary filter, etc., and washed as needed to remove by-product inorganic salts, and then passed through a rotary drying device, an airflow drying device, and aeration Type drying equipment, spray drying equipment, fluidized bed drying equipment, etc. for drying. The drying method may be any one of continuous or batch, normal pressure or vacuum. In this way, the metal soap of the present invention can be obtained.

When the metal soap thus obtained is dispersed in water at a concentration of 2% by mass, the pH is 5.0 to 7.5. The obtained metal soaps may be used alone or in combination with metal soaps containing different metals.

(2) Thermoplastic resin

The thermoplastic resin used in the present invention is not particularly limited, and for example, the following resins can be mentioned: chlorine-containing resins such as polyvinyl chloride, chlorinated polyvinyl chloride, chlorinated polyethylene, vinyl chloride/vinyl acetate copolymer, and the Polymer mixtures of chlorine resins and other resins; polyolefin resins such as low-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, polymer mixtures of polyolefin resins, polymerization of polyolefin resins and other resins mixtures of these resins and copolymers of monomers (alpha olefins) and other monomers that make up these resins; polyamide resins, polymer mixtures of various polyamide resins, polymer mixtures of polyamide resins and other resins, and polymer mixtures that make up polyamides Copolymers of resin monomers and other monomers; polyester resins such as polycarbonate and polyethylene terephthalate, polymer mixtures of various polyester resins, polymer mixtures of polyester resins and other resins And copolymers of monomers constituting polyester resins and other monomers; ABS resins, polymer mixtures of various ABS resins, polymer mixtures of ABS resins and other resins, and monomers constituting ABS resins and other monomers Copolymers; polyacetal resins, polymer mixtures of various polyacetal resins, polymer mixtures of polyacetal resins and other resins, and copolymers of monomers constituting polyacetal resins and other monomers. Among them, polyester resins, polymer mixtures of various polyester resins, polymer mixtures of polyester resins and other resins, and copolymers of monomers constituting polyester resins and other monomers are preferred, and more preferred are polyester resin.

(3) Pentaerythritol ester compound

The thermoplastic resin composition of the present invention contains a pentaerythritol ester compound as needed. The pentaerythritol ester compound is an ester of pentaerythritol and a monovalent saturated fatty acid having 14 to 24 carbon atoms. By containing this ester compound, the lubricity with processing machines or molds during processing is improved. The acid value of the ester compound is preferably 5.0 or less, more preferably 3.0 or less, and the hydroxyl value is preferably 20.0 or less, more preferably 15.0 or less. When the acid value exceeds 5.0 or the hydroxyl value exceeds 20.0, the obtained thermoplastic resin composition may be colored and a decrease in strength may be caused.

(4) Additives

As the additives contained in the thermoplastic resin composition of the present invention as needed, there are, for example, the following compounds or materials: fillers such as talc, mica, calcium carbonate, potassium titanate, and calcium silicate; titanium oxide, carbon black, iron oxide , ultramarine blue and other inorganic pigments; phthalocyanine compounds, quinacridone compounds, anthraquinone compounds, pyrrole compounds and other organic pigments; phenolic compounds, phosphite compounds, hindered phenolic compounds, phosphite compounds, Antioxidants such as phosphate compounds and amine compounds; light stabilizers such as hindered amine compounds, external lubricants such as aliphatic fatty acid ester compounds other than the above-mentioned pentaerythritol ester compounds, paraffin compounds, organic fatty acids, etc.; flame retardants , release agent, antistatic agent, etc.

(5) Thermoplastic resin composition

The thermoplastic resin composition of the present invention contains the above-mentioned metal soap and thermoplastic resin as described above, and may contain a pentaerythritol ester compound and other additives as necessary.

Content of the said metal soap is 0.01-10 mass parts with respect to 100 mass parts of said thermoplastic resins, Preferably it is 0.1-5 mass parts. When the content of the metal soap is less than 0.01 parts by mass, sufficient pigment dispersibility cannot be exhibited. When it exceeds 10 parts by mass, the metal soap floats on the surface of the resin, resulting in a reduction in the appearance. The content of the aforementioned pentaerythritol ester compound is not particularly limited. Preferably, the said pentaerythritol ester compound is 0.001-5 mass parts with respect to 100 mass parts of thermoplastic resins. When the content of the above-mentioned ester compound is less than 0.001 parts by mass, the obtained thermoplastic resin composition may have insufficient lubricity, adhesion to processing equipment may occur, or the appearance of molded products may be poor. When the content exceeds 5 parts by mass, the ester compound may float on the surface of the resin, resulting in poor appearance, lower strength, and the like. In addition, the metal soap used in the present invention hardly causes the above-mentioned ester compound to be colored.

The components of the above-mentioned thermoplastic resin composition, that is, thermoplastic resin, metal soap, and additives contained as required, are kneaded by a mixing method commonly used by those skilled in the art, for example, a ribbon blender, a Henschel mixer , Banbury mixer, drum drum, single-screw extruder, twin-screw extruder, co-kneader, multi-screw extruder, etc. for mixing. Then, it can be molded by a molding method usually used by those skilled in the art, such as injection molding, compression molding, calender molding, rotational molding, etc., and can be used for various molded products, such as automotive fields, OA parts fields, etc. Manufacture of moldings.

Example

Hereinafter, examples are given and the present invention will be described in more detail.

(Preparation example 1: the preparation of metal soap)

In a 3L glass separable (Separable) flask, put mixed fatty acids (containing 2.5% by mass of myristic acid, 30.0% by mass of palmitic acid, 66.4% by mass of stearic acid, 0.8% by mass of arachidic acid and 0.3% by mass of di Dodecanoic acid) 250g (0.90 mol) and water 2500g, and the temperature was raised to 90°C. Then, 72.5 g (0.87 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Thereafter, 221 g (0.46 mol) of a 25% magnesium sulfate aqueous solution was added dropwise over 1 hour while maintaining the temperature at 90°C. After completion of the dropping, the mixture was further stirred at 90° C. for 1 hour. Add 1500 g of water to the obtained mixed fatty acid magnesium slurry, and cool to 65° C. or below. Thereafter, it was filtered with a suction filter, washed twice with 1000 g of water, and dried at 65° C. for 48 hours using a blast dryer to obtain a metallic soap.

The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the following methods. The results are shown in Table 1.

(1) Free fatty acids

Accurately weigh 5g of metal soap and put it into a beaker, add 50ml of ether/ethanol mixed solvent, stir and let stand for 30 minutes. Then, filter using 5B filter paper, titrate with 1/10N potassium hydroxide-ethanol solution, and calculate the amount of free fatty acid according to the following formula. In the formula, MW represents the molecular weight of fatty acid, A represents the dropping amount of potassium hydroxide titration solution, and f represents the coefficient of potassium hydroxide titration solution.

Free fatty acid (%)=MW×A(ml)×f/100

(2) Metal content

0.1 g of metal soap was accurately weighed, and heated at 650° C. for 4 hours in a magnetic crucible to remove organic matter. 1 ml of hydrochloric acid was added to the residue to dissolve it, and water was added to make it 100 ml. This solution was used as a sample, and the metal content was measured by atomic absorption spectrometry.

(3) Melting point

Measurement was performed by the method described in JIS-K0064.

(4) Moisture

Measurement was performed by the method described in JIS-K0067. Drying was performed at 105°C using 2 g of metal soap as a sample.

(5)pH

Using an aqueous solution containing 0.2% by mass of a nonionic surfactant (Nonion NS-210, manufactured by NOF Corporation), an aqueous dispersion containing 2% by mass of metal soap was prepared, and the pH was measured at 25°C.

(Preparation example 2: the preparation of metal soap)

Into a 3L glass-made separable flask, 250 g (0.90 mol) of the mixed fatty acid of Preparation Example 1 and 2500 g of water were added, and the temperature was raised to 90°C. Then, 73 g (0.87 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Thereafter, 291 g (0.45 mol) of a 25% zinc sulfate aqueous solution was added dropwise over 1 hour while maintaining the temperature at 90°C. The obtained mixed fatty acid zinc slurry was filtered with a suction filter, washed three times with 1000 g of water, and dried at 80° C. for 30 hours using a blast dryer to obtain a metal soap. The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the same method as in Preparation Example 1. The results are shown in Table 1.

(Preparation example 3: the preparation of metal soap)

Into a 5 L glass separable flask, 250 g (1.25 mol) of lauric acid and 2500 g of water were added, and the temperature was raised to 90°C. Then, 99 g (1.19 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Then, the temperature was raised to 95°C. While maintaining at 95° C., 200 g (0.63 mol) of a 35% calcium chloride aqueous solution was added dropwise over 1 hour. After completion of the dropping, the mixture was further stirred at 95° C. for 1 hour. The resulting calcium laurate slurry was cooled to 60°C or below while stirring. Then, use the filter chamber volume to be 75cm ³ desktop filter press filter, wash 3 times with the water of 1000g, use blast drier to dry at 70 ℃ for 48 hours, obtain metal soap. The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the same method as in Preparation Example 1. The results are shown in Table 1.

(Preparation example 4: the preparation of metal soap)

In a 5 L glass detachable flask, 250 g (0.90 mol) of the mixed fatty acid of Preparation Example 1 and 2500 g of water were added, and the temperature was raised to 90°C. Then, 71.7 g (0.86 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Thereafter, 917 g (0.44 mol) of a 10% barium chloride aqueous solution was dropped over 1 hour while maintaining the temperature at 90°C. After completion of the dropping, the mixture was further stirred at 90° C. for 1 hour. The obtained mixed fatty acid barium slurry was filtered with a suction filter, washed three times with 1000 g of water, and dried at 80° C. for 30 hours using a blast dryer to obtain a metal soap. The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the same method as in Preparation Example 1. The results are shown in Table 1.

(Preparation example 5: the preparation of metal soap)

Into a 5 L glass-made separable flask, 250 g (0.90 mol) of the mixed fatty acid of Preparation Example 1 and 2500 g of water were added, and the temperature was raised to 90°C. Then, 73 g (0.87 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Thereafter, 146 g (0.46 mol) of a 35% calcium chloride aqueous solution was added dropwise over 1 hour while maintaining the temperature at 90°C. After completion of the dropping, the mixture was further stirred at 90° C. for 1 hour. 1500 g of water was added to the obtained slurry, and cooled to 65° C. or lower. Thereafter, it was filtered with a suction filter, washed twice with 1000 g of water, and dried at 65° C. for 48 hours using a blast dryer to obtain a metal soap. The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the same method as in Preparation Example 1. The results are shown in Table 1.

(comparative preparation example 1)

Into a 5 L glass-made separable flask, 250 g (0.90 mol) of the mixed fatty acid of Preparation Example 1 and 2500 g of water were added, and the temperature was raised to 90°C. Then, 77 g (0.92 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Thereafter, 355 g (0.55 mol) of a 25% zinc sulfate aqueous solution was added dropwise over 1 hour while maintaining the temperature at 90°C. After completion of the dropping, the mixture was further stirred at 90° C. for 1 hour. The obtained mixed fatty acid zinc slurry was filtered with a suction filter, washed three times with 1000 g of water, and dried at 80° C. for 30 hours using a blast dryer to obtain a metal soap. The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the same method as in Preparation Example 1. The results are shown in Table 1.

(comparative preparation example 2)

Into a 5 L glass-made separable flask, 250 g (0.90 mol) of the mixed fatty acid of Preparation Example 1 and 2500 g of water were added, and the temperature was raised to 90°C. Then, 77 g (0.92 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Thereafter, 211 g (0.46 mol) of a 25% magnesium sulfate aqueous solution was added dropwise over 1 hour while maintaining the temperature at 90°C. After completion of the dropping, the mixture was further stirred at 90° C. for 1 hour. 1500 g of water was added to the resulting slurry and cooled to 65°C or below. Thereafter, it was filtered with a suction filter, washed twice with 1000 g of water, and dried at 65° C. for 48 hours using a blast dryer to obtain a metal soap. The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the same method as in Preparation Example 1. The results are shown in Table 1.

(comparative preparation example 3)

Into a 5 L glass-made separable flask, 250 g (0.90 mol) of the mixed fatty acid of Preparation Example 1 and 2500 g of water were added, and the temperature was raised to 90°C. Then, 77 g (0.92 mol) of 48% sodium hydroxide aqueous solution was added, and it stirred at the same temperature (90 degreeC) for 1 hour. Thereafter, 152 g (0.46 mol) of a 35% calcium chloride aqueous solution was added dropwise over 1 hour while maintaining the temperature at 90°C. After completion of the dropping, the mixture was further stirred at 90° C. for 1 hour. 1500 g of water was added to the resulting slurry and cooled to 65°C or below. Thereafter, it was filtered with a suction filter, washed twice with 1000 g of water, and dried at 65° C. for 48 hours using a blast dryer to obtain a metal soap. The free fatty acid content, metal content, melting point, water content and pH of the obtained metal soap were analyzed by the same method as in Preparation Example 1. The results are shown in Table 1.

Table 1

*Molar ratio of 1...1-valent base compound to fatty acid

(Examples 1 to 5 and Comparative Examples 1 to 4: Preparation and Evaluation of Thermoplastic Resin Compositions)

1 part by mass of each metal soap obtained in Preparation Examples 1 to 5 and Comparative Preparation Examples 1 to 3, 100 parts by mass of polycarbonate resin particles (Upiron manufactured by Mitsubishi Engineering Plastics Co., Ltd.), titanium oxide (Ishihara 10 parts by mass of Industrial Co., Ltd.) and 1 part by mass of carbon black (Tokai Carbon Co., Ltd.) were mixed. Then, it was melt-kneaded and extruded at 280° C. using a twin-screw extruder with an inner diameter of 20 mm, and pelletized by a pelletizer. After each granule obtained is fully dried, use vertical injection molding machine, under the molding temperature of 280 ℃, the mold temperature of 90 ℃, injection molding, prepare the polycarbonate sheet of 70mm * 70mm * 2mm (they are prepared according to the preparation example 1 to 5 and the order of Comparative Preparation Examples 1 to 3 are respectively designated as test pieces 1 to 8). In addition, pellets were produced in the same manner as above except that the metal soap was not included, and a polycarbonate sheet (as test piece 9) was prepared. About the obtained test pieces 1-9, the number average molecular weight was measured using the gel permeation chromatography (GPC, manufactured by Tosoh Corporation), and the appearance and impact strength were evaluated as follows. The results are shown in Table 2.

(1) Appearance (with or without color unevenness)

For the test piece, the presence or absence of color unevenness was observed with the naked eye. The case where color unevenness was not observed at all was designated as ○; the case where color unevenness was observed near the injection port was designated as △; and the case where color unevenness was observed as a whole was designated as x.

(2) Impact strength

The test piece obtained by injection molding was sheared to prepare a notched test piece for the Izod impact test, and the impact strength was measured.

Table 2

*1...PC: polycarbonate

*2...Metal soap/thermoplastic resin (mass ratio)

As can be seen from the results in Table 2, the test pieces (test pieces 1-5) containing the metal soaps of the preparation examples compared with the test pieces (test pieces 6-8) containing the metal soaps of the comparative preparation examples 1-3, the polycarbonate The decrease in the average molecular weight of the ester is small, and the decrease in impact strength is also small. In addition, the test piece 9 (comparative example 4) which did not contain metal soap was found to have color unevenness as a whole and was extremely poor in appearance.

(Examples 6 to 10 and Comparative Examples 5 to 7: Deterioration preventing effect by combined use with phenolic antioxidants)

1 part by mass of each metal soap obtained in Preparation Examples 1 to 5 and Comparative Preparation Examples 1 to 3, polypropylene particles (Mitsui Polypro, manufactured by Mitsui Chemicals, Ltd.) were mixed at 180° C. ) and 0.1 part by mass of butylated hydroxytoluene (manufactured by Eppy Aiko Polysin Co., Ltd. Yoshinotsux) were stirred for 5 minutes. Then, press molding was performed to prepare polypropylene test pieces having a width of 200 mm, a length of 200 mm, and a thickness of 2 mm (these were respectively designated as test pieces 10 to 17 in the order of Preparation Examples 1 to 5 and Comparative Preparation Examples 1 to 3). Then, these test pieces were placed in a blast dryer and stored at 60° C. for 10 days, and the coloring (yellowing of the resin) after storage was evaluated. Evaluation was carried out by visual observation, and the case where no coloring was observed was made ◯; and the case where coloring was observed was made x. The results are shown in Table 3.

table 3

*1...PP: Polypropylene (granule)

*2...Metal soap/thermoplastic resin (mass ratio)

As can be seen from the results in Table 3, in the test pieces (test pieces 10-14) using the metal soaps of the preparation examples, no yellowing was found at all, while the test pieces using the metal soaps of the comparative preparation examples 1-3 (test pieces 15-14) were not found. 17) Both turn yellow.

(Reference example: Does metal soap cause coloring of pentaerythritol ester compounds)

In a vinyl bag, 5 g of the metal soap (mixed fatty acid magnesium) obtained in Preparation Example 1, and 5 g of pentaerythritol stearate (manufactured by NOF Corporation, Unistar-H-476, acid value 2.5, hydroxyl value 14.0) 5 g were shaken and mixed . The mixture was transferred to an alumina cup with a diameter of 6 cm and heated at 200° C. for 60 minutes in a blast dryer. After cooling, for the color of the surface of the mixture, the values of X, Y and Z were obtained according to JIS Z-8722 using a colorimetric color difference meter ZE-2000 type (manufactured by Nippon Denshoku Industries Co., Ltd.), and the degree of yellowness was obtained by the following formula (YI):

Yellowness (YI)＝100(1.28X-1.06Z)/Y

The above results are shown in Table 4.

Yellowness was obtained in the same manner as above except that the metal soap (magnesium fatty acid mixed) obtained in Comparative Preparation Example 2 was used instead of the metal soap obtained in Preparation Example 1 above. The results are shown in Table 4.

Table 4

Yellowness (YI) when used alone Yellowness after mixed ester (YI) The metal soap (mixed fatty acid magnesium) of preparation example 1 17.1 5.9 The metal soap (mixed fatty acid magnesium) of comparative preparation example 2 18.2 35.5 Pentaerythritol Stearate -4.9 ---

As can be seen from the results of Table 4, when the metal soap of Preparation Example 1 and pentaerythritol stearate are mixed and heated, the yellowness (YI) is higher than that of the metal soap of Comparative Preparation Example 2 and the above-mentioned ester mixed and heated. Low. Because the metal soap of Preparation Example 1 and the metal soap of Comparative Preparation Example 2 have no large difference in yellowness before mixing, it can be seen that the metal soap used in the present invention is less likely to make pentaerythritol esters than other metal soaps. Compound coloring.

(Examples 11 to 12 and Comparative Example 8: anti-staining effect and surface gloss effect)

Metal soaps obtained in Preparation Example 1 and Comparative Preparation Example 2, titanium oxide (manufactured by Ishihara Sangyo, Tape), polycarbonate resin particles (manufactured by Mitsubishi Engineering Plastic Co., Ltd. Uppiron) and the pentaerythritol stearate used in the reference example were mixed. Then, melt kneading and extrusion were carried out at 280° C. using a twin-screw extruder with an inner diameter of 20 mm, and pelletized by a pelletizer. After the obtained particles are fully dried, use a vertical injection molding machine to injection mold at a molding temperature of 280°C and a mold temperature of 90°C to prepare polycarbonate sheets of 70mm * 70mm * 2mm (they are respectively used as test Tablets 18-20). About these test pieces 18-20, coloring and surface gloss of resin were evaluated as follows. The results are shown in Table 5.

(1) Coloring of resin

For the test piece, the yellowness (YI) was measured using a color computer. When the value of YI was 10.0 or less, it was judged that there was no substantial coloration, and when it exceeded 10.0, it was judged that there was significant coloration.

(2) surface gloss

The surface of the test piece was visually observed, and the case where the surface had a uniform gloss was set as ◯; the case where a part of the surface lost its gloss was set as △; and the case where the surface had no gloss at all was set as ×.

table 5

*1...Pentaerythritol Stearate

From the results in Table 5, it can be seen that the test piece 18 containing the metal soap of Preparation Example 1 and the pentaerythritol ester compound and the test piece 19 containing only the metal soap of Preparation Example 1 were hardly colored. Furthermore, since the test piece 18 contained an ester compound, it was excellent in surface gloss. In contrast, the test piece 20 containing the metal soap and the pentaerythritol ester compound of Comparative Preparation Example 2 was yellowed.

Industrial Applicability

The thermoplastic resin composition of the present invention is excellent in dispersibility of pigments, fillers, and the like, and is less prone to decrease in the molecular weight of the resin. Further, even when an antioxidant is contained in the thermoplastic resin composition of the present invention, the antioxidant effect is not hindered. In particular, when a phenolic antioxidant is contained, the phenolic antioxidant is less likely to be decomposed and coloration on the resin is less likely to occur compared with a thermoplastic resin composition comprising a conventional metal soap. Therefore, a phenolic antioxidant can be contained stably in a resin composition. Furthermore, when a pentaerythritol ester compound is contained, the lubricity at the time of processing improves further. Furthermore, even when a pentaerythritol ester compound is contained, coloring of the resin due to coloring of the ester compound is less likely to occur. The thermoplastic resin composition of the present invention is used in, for example, the field of automobiles, the field of OA parts, and the like.

Claims (7)

1. A thermoplastic resin composition comprising a metal soap and a thermoplastic resin, wherein the metal soap is obtained by reacting a fatty acid alkali compound salt with a divalent metal salt in an aqueous solution; The divalent metal salt is calcium chloride, calcium acetate, magnesium chloride, magnesium sulfate, copper sulfate, barium chloride, zinc chloride or zinc sulfate, and the thermoplastic resin is polyester resin or polyolefin resin. The fatty acid alkali compound salt is obtained by reacting a fatty acid with 6 to 24 carbon atoms and a monovalent alkali compound at a ratio of 1 mole: 0.90 to 0.99 moles, The content of the metal soap is 0.01 to 10 parts by mass relative to 100 parts by mass of the thermoplastic resin. 2. The thermoplastic resin composition according to claim 1, wherein the metal constituting the metal soap is calcium or magnesium. 3. The thermoplastic resin composition according to claim 1, wherein, with respect to 100 parts by mass of the thermoplastic resin, pentaerythritol and a monovalent saturated compound having 14 to 24 carbon atoms are further contained in a ratio of 0.001 to 5 parts by mass. Esters of fatty acids. 4. The thermoplastic resin composition according to claim 2, wherein, with respect to 100 parts by mass of the thermoplastic resin, pentaerythritol and a monovalent saturated compound having 14 to 24 carbon atoms are further contained in a ratio of 0.001 to 5 parts by mass. Esters of fatty acids. 5. The thermoplastic resin composition according to claim 3, wherein the ester compound has an acid value of 5.0 or less and a hydroxyl value of 20.0 or less. 6. The thermoplastic resin composition according to claim 4, wherein the ester compound has an acid value of 5.0 or less and a hydroxyl value of 20.0 or less. 7. The thermoplastic resin composition according to any one of claims 1 to 6, wherein the thermoplastic resin is a polyester resin.