JPS6315304B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for melt molding a resin composition, and more specifically, when melt molding a resin composition comprising an aromatic polyester polycarboxylic anhydride and a polyamide, The present invention relates to a method of melt-molding a composition containing a specific amount of water. Aromatic polyester polycarboxylic acid anhydride produced from terephthalic acid or isophthalic acid, functional derivatives thereof, bisphenols or functional derivatives thereof has high heat distortion temperature and high thermal decomposition temperature, and has good mechanical properties, It is a heat-resistant thermoplastic resin with excellent electrical properties, and is expected to have a wide range of applications in fields that require high performance as engineering plastics. However, due to their high melt viscosity, these materials have the drawbacks of inferior moldability compared to general thermoplastic resins, insufficient solvent resistance in practical terms, and stress resistance. There was a problem that stress cracks were likely to occur. On the other hand, resin compositions made of aromatic polyester polycarboxylic acid anhydride and polyamide have disadvantages of polyamide such as low heat distortion temperature, large dimensional changes due to hygroscopicity, and mechanical and electrical problems due to moisture absorption. The problem of relative decline in properties has been significantly improved, and the aromatic polyester polycarboxylic acid anhydride has the above-mentioned moldability and
Problems such as solvent resistance and stress crack resistance have been greatly improved, and the product has excellent properties such as high heat distortion temperature, good electrical and mechanical properties, and good fluidity during molding. It is a resin composition. Thus, such a resin composition exhibits much better melt flow than would be inferred from the additivity of the amounts of the aromatic polyester polycarboxylic anhydride component and the polyamide component constituting the resin composition. However, this may be because the fluidity is clearly poorer than that of polyamide alone, and the melt of polyamide is less thermally stable than that of aromatic polyester polycarboxylic acid anhydride, or the interaction between the two causes melting. Perhaps because it has a negative effect on the thermal stability of the body, when molding products with poor fluidity, such as thin products, when molding products are being molded, molding is performed at high temperatures to improve fluidity. In such cases or when stagnation occurs during molding, the resin composition decomposes and deteriorates, resulting in problems such as contamination of the appearance and insufficient mechanical properties. In particular, when such resin compositions contain aromatic halogen compounds or flame retardant aids, there is a serious problem in thermal stability, as is often the case with resins and resin compositions containing halogen compounds. If even a small amount of the molten material stagnates, it turns black and significantly contaminates the appearance of the molded product.Also, it was observed that the mechanical properties tended to deteriorate significantly due to stagnation. Therefore, an object of the present invention is to maintain the resin composition even if a resin composition consisting of (A) aromatic polyester polycarboxylic anhydride and (B) polyamide is melt-molded under relatively harsh conditions. The object of the present invention is to provide a melt-molding method that can prevent the decomposition of materials and maintain the good mechanical properties and appearance of the resin composition. As a result of intensive studies to achieve the above object, the present inventors found that the above-mentioned problems can be solved by an extremely simple method of melt molding using a resin composition containing a specific amount of water. This fact was discovered and the present invention was developed. That is, the present invention provides at least one compound selected from the group consisting of (A)(a) terephthalic acid and isophthalic acid.
(b) selected from the group consisting of dichloride of terephthalic acid, alkyl diester of terephthalic acid, aryl diester of terephthalic acid, dichloride of isophthalic acid, alkyl diester of isophthalic acid, and aryl diester of isophthalic acid; A functional derivative of at least one aromatic dicarboxylic acid [however, the molar ratio of terephthalic acid groups to isophthalic acid groups, which is the sum of (a) and (b) above, is 9:1 to 1:9] and (c) the following: When melt-molding a resin composition consisting of an aromatic polyester polycarboxylic acid anhydride obtained from bisphenols represented by the general formula [] and (B) polyamide, the (A) component is added to the resin composition. The gist of the present invention is a method for melt molding a resin composition, characterized in that water is present in an amount of 0.04 to 1% by weight based on the total amount of component (B). However, -X- is -O-, -S-, -SO ₂ -, -
selected from the group consisting of CO-, alkylene group and alkylidene group, R ₁ , R ₂ , R ₃ , R ₄ , R' ₁ , R' ₂ ,
R' ₃ and R' ₄ are selected from the group consisting of hydrogen atoms and hydrocarbon groups. The present invention will be explained in detail below. The aromatic polyester polycarboxylic acid anhydride used in the present invention comprises (a) at least one aromatic dicarboxylic acid selected from the group consisting of terephthalic acid and isophthalic acid, and (b) dichloride of terephthalic acid, terephthalic acid (c) a functional derivative of at least one aromatic dicarboxylic acid selected from the group consisting of an alkyl diester of terephthalic acid, an aryl diester of terephthalic acid, a dichloride of isophthalic acid, an alkyl diester of isophthalic acid, and an aryl diester of isophthalic acid; It is obtained from bisphenols represented by the formula [].
However, the molar ratio of terephthalic acid groups and isophthalic acid groups, which is the sum of (a) aromatic dicarboxylic acid and (b) functional derivative of aromatic dicarboxylic acid, is 9:1 to 1:9.
It is. Examples of bisphenols represented by the above general formula [] include 4,4'-dihydroxy-diphenyl ether, bis(4-hydroxy-2-methyl-phenyl)-ether, and bis(4-hydroxyphenyl). -sulfide, bis(4-hydroxyphenyl)-sulfone, bis(4-hydroxyphenyl)-ketone, bis(4-hydroxyphenyl)-methane, bis(4-hydroxy-3-
Methyl-phenyl)-methane, 1,1-bis(4'-hydroxyphenyl)-ethane, 2,2-bis(4'-hydroxy-3'-methylphenyl)-propane, 1,1-bis(4' -hydroxyphenyl)-n-butane, bis(4-hydroxyphenyl)-phenylmethane, bis(4-hydroxyphenyl)-diphenylmethane, bis(4-hydroxyphenyl)-4-methylphenylmethane, 1,
Examples include 1-bis(4'-hydroxyphenyl)-cyclohexane, bis(4-hydroxyphenyl)-cyclohexylmethane, and 2,2-bis(4'-hydroxynaphthyl)-propane, but the most common A typical product produced is 2,2-bis(4'-hydroxyphenyl)-propane, which is called bisphenol A. If necessary, mixtures of the bisphenols or bisphenols and small amounts of other divalent compounds, such as dihydroxynaphthalenes such as 2,2'-dihydroxydiphenyl, 2,6-dihydroxynaphthalene, hydroquinone, resorcinol, 2 , 6-dihydroxytoluene, 3,6
-dihydroxytoluene can be used. The phenylene group of the terephthalic acid or isophthalic acid or functional derivative thereof used in the present invention may be substituted with an alkyl group. The aromatic polyester polycarboxylic acid anhydride used in the present invention may be one in which alkylene glycol such as ethylene glycol or neopentyl glycol is incorporated into a part of the main chain, or one in which an alkylene glycol such as ethylene glycol or neopentyl glycol is incorporated into a part of the main chain. The portion may contain a different type of bond, such as a carbonate bond, an amide bond, or an ether bond, but the amount thereof is 30 mol%.
The content below is particularly preferably 10 mol% or less. The aromatic polyester polycarboxylic acid anhydride used in the present invention can be obtained by interfacial polymerization of aromatic dicarboxylic acid, aromatic dicarboxylic acid dichloride, and bisphenol, as described in Japanese Patent Publication No. 44-879. It can be synthesized by reaction. The aromatic polyester polycarboxylic acid anhydride used in the present invention is preferably one in which the proportion of acid anhydride units is in the range of 0.1 to 99% with respect to the total amount of ester bond units and acid anhydride bond units. In particular, the proportion of acid anhydride binding units is
A content in the range of 0.5 to 20% is preferable in terms of mechanical properties and the like. The polyamide used in the present invention is represented by the following general formula [] or []. Here, R ₅ , R ₆ and R ₇ represent an alkylene group. The polyamides used in the present invention include polymers formed by condensation reactions of diamines and dibasic acids, self-condensation of amino acids, and gravimetric reactions of lactams. Further, a part of these alkylene groups may be replaced with an aromatic ring or an aliphatic ring. Further, a part of the amide bond may be replaced with another bond such as an ester bond. The polyamide used in the present invention may be any polyamide as long as it is represented by the above general formula, and examples thereof include polyhexamethylene adipamide, polycaprolactam, polyhexamethylene sebacamide, polydecamethylene adipamide, etc. However, particularly preferred is polycaprolactam. Also,
The polyamide used in the present invention is preferably one having a relative viscosity of 2 or more, particularly 2.8 or more at 25° C. in 96% sulfuric acid at a concentration of 1 g/100 c.c. in order to exhibit advanced mechanical properties. The resin composition used in the present invention consists of component (A) and component (B).
The blending ratio of component (A) and component (B) is preferably in the range of 1:9 to 9:1, particularly 3:7 to 7:3, by weight. Components (A) and (B) for producing the resin composition used in the present invention may be mixed by any method. For example, both may be mixed in a dry solid state, or both may be mixed in a dry solid state. Although they may be melt-mixed, it is preferable to melt-mix the two in a state in which they contain water of 0.04 to 1% by weight, particularly 0.07 to 0.5% by weight based on the total amount of both. In the method of the present invention, the proportion of water contained in the resin composition is 0.04 to 1% by weight, preferably 0.07 to 0.5% by weight, corresponding to the total amount of components (A) and (B). If the amount of water present in the resin composition is less than 0.04% by weight, the effect of the present invention will be insufficient, while if it is more than 1% by weight, problems such as easy foaming will occur in the molded product. . To add moisture to the resin composition, for example, the powder, pellets, or chips of component (A) and (B) may absorb moisture uniformly, or the moisture may be attached to their surface layers. Good too. Alternatively, a method may be used in which powder, pellets or chips of component (A) or component (B) containing a high concentration of water are mixed with well-dried powder, pellets or chips. The resin composition used in the present invention may contain a flame retardant or a flame retardant aid, if necessary, for the purpose of improving flame retardancy, and the method of the present invention is particularly effective in such cases. Preferred flame retardants are aromatic halogen compounds, and particularly preferably used aromatic halogen compounds are stable in the melt processing temperature range of the resin composition consisting of aromatic polyester polycarboxylic anhydride and polyamide,
It decomposes only at the combustion temperature of the resin composition. More preferable aromatic halogen compounds include decabromodiphenyl ether, hexabromodiphenyl ether, hexabromobenzene, pentabromotoluene, pentabromoethylbenzene, and decabromodiphenyl sulfone. , bis(tribromophenoxy)ethylene, decabromodiphenyl,
Octabromodiphenyl, 2,2-bis(4'-hydroxyethoxy-3',5'-dibromophenyl)
Propane, bis(4-hydroxy-3,5-dibromophenyl)sulfone, etc. are mentioned. Among these many aromatic halogen compounds, decabromodiphenyl ether is particularly excellent from various viewpoints such as thermal stability, flame retardant effect, non-migration, influence on heat distortion temperature of resin composition, and economic efficiency. There is. Aromatic halogen compounds can be used alone or in combination of two or more. Examples of flame retardant aids include organic antimony compounds,
Examples include inorganic antimony compounds, zinc borate, barium metaborate, zirconium oxide, etc.
In particular, antimony trioxide has a remarkable flame retardant effect. The amount of the aromatic halogen compound and flame retardant aid added is preferably such that the total weight thereof is about 0.5 to 40% by weight based on the total weight of the resin composition. Further, the blending ratio of the aromatic halogen compound and the flame retardant aid is preferably in the range of 1:0.01 to 1:2 by weight. When a flame retardant or a flame retardant aid is contained in the resin composition, water can be added to the side of these additives when kneading them into the resin composition. The resin composition used in the present invention may include acrylonitrile-butadiene rubber, styrene-butadiene rubber, polyester rubber, etc. for the purpose of further increasing mechanical properties such as impact strength and elongation at break, and improving heat deterioration resistance. rubber material,
ABS, polycarbonate, polysulfon, polyether sulfon, polyethylene, polypropylene, polyurethane, polystyrene, EVA,
It may also contain polyacrylic acid ester, polytetrafluoroethylene, ionomer, methyl methacrylate, polyalkylene phenylene ester, and polyalkylene phenylene ester ether. The amounts of these polymer components added are component (A) and component (B).
It is preferably within 30% by weight based on the total amount of components. Furthermore, glass fiber, an inorganic reinforcing filler, a heat resistant agent, a weathering agent, and a discoloration inhibitor can also be added. In such a case, various polymers and other components may contain water in advance. In the present invention, when melt-molding the resin composition, it is necessary to allow 0.04 to 1% by weight of water to be present in the resin composition based on the total amount of components (A) and (B). It is. As the melt molding method, various known methods such as profile extrusion, injection molding, blow molding, etc. can be adopted, but the melt molding conditions include a temperature range of about 200 to 320°C for 1 second to 320°C.
Preferably, conditions provide a residence time of about 30 minutes. The resin composition composed of components (A) and (B) in the present invention can withstand melt molding at relatively high temperatures, and even when stored at high temperatures, the resin composition only becomes slightly brownish and does not have any significant appearance defects. However, the molecular weight and mechanical properties, especially impact properties, are significantly reduced. However, by adopting the method of the present invention, these problems can be minimized and the range of molding conditions can be greatly expanded from a practical standpoint. In particular, when a flame retardant or flame retardant aid is contained in a resin composition consisting of components (A) and (B), good appearance and good mechanical properties can be obtained at relatively low temperatures and with little retention. Although a molded product with a high temperature can be obtained, the molded product may decompose into a blackish brown color even if it remains for a short time, or even if it is molded under less severe conditions, there will be a part of the molded product that remains in the molding machine. Contamination causes a major problem in appearance, and even if the mechanical properties do not deteriorate significantly, due to the occurrence of "scorch",
Although the scope of its application has been limited, by using the method of the present invention, the above-mentioned problem of "burning" is significantly improved, making it easier to mold large molded products or multiple small items in injection molding. A great effect was achieved. Although it is not clear what mechanism causes the effects of the present invention in the method of the present invention, it is possible to improve the thermal stability of the resin composition of the present invention during melt molding by such a very simple method. This not only significantly reduces the number of defective products during molding, but also enables melt molding at higher temperatures than before, which lowers the melt viscosity of the resin composition and improves its fluidity. This has made it possible to easily mold complex molded products that were previously virtually impossible to mold into good quality products, greatly contributing to the development of applications for resin compositions. Further, the method of the present invention does not require expensive additives and is extremely economical, and can be suitably used in various melt moldings such as injection molding, extrusion molding, and blow molding. Hereinafter, the present invention will be specifically explained with reference to Examples. In the following examples, the logarithmic viscosity in a 6/4 weight ratio mixture of phenol/tetrachloroethane,
It was measured at a concentration of 1 g/100 c.c. and a temperature of 25°C. Reference Example 1 An alkali of a methylene chloride solution of a mixed acid chloride in which the molar ratio of terephthalic acid dichloride and isophthalic acid dichloride is 1:1, and a mixture of bisphenol A and terephthalic acid in a molar ratio of 9.5:0.5. Prepare an aqueous solution, take these solutions so that the ratio of the bisphenol A component and the acid component after mixing is equimolar, mix them with vigorous stirring, and use an interfacial polymerization method to form an aromatic compound. A polyester polycarboxylic anhydride was produced. The logarithmic viscosity of this aromatic polyester carboxylic acid anhydride is
0.60, and the ratio of acid anhydride bond units to the total amount of ester bond units and acid anhydride bond units was 5 mol%. Reference Example 2 An aromatic polyester copolymer was produced by an interfacial polymerization method using a methylene chloride solution of a mixed acid chloride with a molar ratio of terephthalic acid dichloride and isophthalic acid dichloride of 1:1 and an alkaline aqueous solution of bisphenol A. . The logarithmic viscosity of this copolymer is
It was 0.96. Examples 1 to 5, Comparative Examples 1 and 2 The aromatic polyester polycarboxylic acid anhydride produced in Reference Example 1 was mixed with nylon 6 (manufactured by Unitika Co., Ltd.).
After mixing in a supermixer at a ratio of 1:1 (weight ratio) with a concentration of 1 g/100 c.c. in 96 wt% sulfuric acid and a relative viscosity of 2.6 at a temperature of 25°C, the moisture content of the mixture becomes 0.11 wt%. The mixture was dried with hot air as described above, and then extruded using a high kneading type extruder at a barrel temperature of 260°C to obtain pellets. The logarithmic viscosity of this pellet was 0.88. The pellets are left in the air for a long time to absorb moisture and then dried. By varying the drying time,
Pellets having various moisture contents as shown in the table were obtained. Next, the temperature of the injection molding machine (front, middle, and rear of the cylinder was set to 300℃, 300℃, and 250℃, respectively).
After melting and retaining these pellets for 5 minutes at a temperature of 60°C, the pellets were molded into 1/8 inch thick tensile impact specimens of size S specified in ASTM-1822, and molded. The appearance of the product and the foaming state inside the molded product were observed, and the logarithmic viscosity and tensile impact strength of the molded product were measured. The results obtained were as shown in Table 1. Comparative Examples 3 to 5 The aromatic polyester copolymer produced in Reference Example 2 was superimposed with the same nylon 6 used in Examples 1 to 5 and Comparative Examples 1 and 2 at a ratio of 1:1 (weight ratio). After mixing with a mixer, the moisture content of the mixture is
The pellets were dried with hot air to a concentration of 0.11% by weight, and then extruded using the same high-kneading extruder used in Examples 1 to 5 and Comparative Examples 1 and 2, with the barrel temperature set at 260°C, to form pellets. Obtained. The logarithmic viscosity of this pellet was 0.92. The pellets were left in the air for a long time to absorb moisture and then dried to obtain pellets having various moisture contents as shown in Table 1. Next, Examples 1 to 5,
Using the same injection molding machine as that used in Comparative Examples 1 and 2, test pieces were molded in the same manner as in Examples 1 to 5 and Comparative Examples 1 and 2, and the appearance of the molded products and the quality of the molded products were evaluated. The internal foaming state was observed, and the logarithmic viscosity and tensile impact strength of the molded product were measured. The results obtained were as shown in Table 1. A composition consisting of well-dried aromatic polyester polycarboxylic anhydride and polyamide is 300
℃ (Comparative Example 1), but this can be prevented by the presence of an appropriate amount of moisture (Examples 1 to 5).
On the other hand, in the case of a composition consisting of an aromatic polyester copolymer and a polyamide, although the effect of the presence of water is observed, it is relatively stable at 300°C even when thoroughly dried (Comparative Example 3). , the effect is not clear compared to a composition consisting of aromatic polyester polycarboxylic anhydride and polyamide. 【table】

Claims (1)

[Scope of Claims] 1 (A) (a) at least one aromatic dicarboxylic acid selected from the group consisting of terephthalic acid and isophthalic acid, (b) dichloride of terephthalic acid, alkyl diester of terephthalic acid, terephthalic acid A functional derivative of at least one aromatic dicarboxylic acid selected from the group consisting of aryl diester of isophthalic acid, dichloride of isophthalic acid, alkyl diester of isophthalic acid, and aryl diester of isophthalic acid [provided that The total molar ratio of terephthalic acid groups and isophthalic acid groups is 9:1 to 1:
9] and (c) a bisphenol represented by the following general formula [], and (B) a polyamide. 1. A method for melt-molding a resin composition, characterized in that water is present in the product in an amount of 0.04 to 1% by weight based on the total amount of components (A) and (B). However, -X- is -O-, -S-, -SO ₂ -, -
selected from the group consisting of CO-, alkylene group and alkylidene group, R ₁ , R ₂ , R ₃ , R ₄ , R' ₁ , R' ₂ ,
R' ₃ and R' ₄ are selected from the group consisting of a hydrogen atom and a hydrocarbon group.