JPS6126567B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention improves fluidity during processing and prevents stress cracking (cracks in stress environments).
The present invention relates to an improved method for producing polyarylene esters. More specifically, when producing polyarylene esters from aromatic dicarboxylic acids or their ester-forming derivatives (hereinafter referred to as functional derivatives) and bisphenols or their functional derivatives, trihydric or higher alcohols or The present invention relates to a method for producing a branched thermoplastic polyarylene ester whose melt viscosity is highly dependent on pressure by adding a specific amount of the functional derivative and performing a condensation reaction. Polyarylene esters synthesized from aromatic dicarboxylic acids or their functional derivatives and bisphenols have been well known for a long time. Methods for producing such polyarylene esters include interfacial polycondensation method (Japanese Patent Publication No. 1959-1983),
Methods such as solution polycondensation method (Japanese Patent Publication No. 37-5599) and melt polycondensation method (Japanese Patent Publication No. 38-15247) are known. The polyarylene ester obtained in this way,
In particular, terephthalic acid and isophthalic acid as aromatic divalent carboxylic acids, and as bisphenols,
It is also well known that copolymers obtained from bisphenol A (2,2-bis-(4-hydroxyphenyl)-propane) have excellent properties. In other words, it has excellent properties such as tensile strength, impact strength, heat distortion temperature, transparency, flame retardance, and electrical properties, and is widely used as a material for various molded products, films, fibers, and coatings by extrusion molding, injection molding, etc. It is also known that it can be used in the field. The disadvantage of such polyarylene esters is that they have a high melt viscosity, so they cannot be used for injection molding, extrusion molding,
The problem is that the fluidity is poor when molded by other methods. Therefore, it is not possible to obtain large molded products, and its uses are limited. It has also been pointed out that molded products crack when placed under stress (stress cracking). One way to avoid these drawbacks is to add a plasticizer to the thermoplastic resin. Although this method is effective in improving fluidity, it significantly lowers the softening point of the polyarylene ester and thereby impairs its heat resistance. This is not a preferable method because it causes decomposition of the resin during processing, coloring, and various damage due to decomposition and evaporation of the plasticizer during molding. In view of the current situation, the present inventor conducted research on a method for improving fluidity without significantly reducing heat resistance, which is a characteristic of polyarylene esters, and found that a specific amount of trihydric or higher alcohol or its functional derivative, By using it as a branching agent and giving the polyarylene ester an appropriate branched structure, the pressure dependence of the melt viscosity increases, making it more fluid than linear polyarylene ester when molded under high pressure such as injection molding. The present invention was achieved based on the discovery that this can be improved. Furthermore, it has been found that the branched thermoplastic polyarylene esters according to the invention also exhibit excellent resistance to stress cracking. That is, the present invention provides for the production of polyarylene esters from aromatic dicarboxylic acids or functional derivatives thereof and bisphenols or functional derivatives thereof.
Relating to a method for producing a branched thermoplastic polyarylene ester that exhibits good fluidity and excellent resistance to stress cracking, by adding 0.01 to 5 mol parts per 100 mol parts and carrying out a condensation reaction. It is something. Specific examples of aromatic dicarboxylic acids or functional derivatives thereof used in the present invention include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, and nuclear alkyl-substituted and nuclear halogenated derivatives thereof. Further, examples of these functional derivatives include acid chloride, phenyl ester, and alkyl ester. Preferred are terephthalic acid, isophthalic acid and functional derivatives thereof. More preferably, a mixture of terephthalic acid and isophthalic acid,
or a mixture of functional derivatives thereof. The bisphenols used in the present invention are represented by the following general formula. In the above formula, Ar ¹ represents an aromatic nucleus such as a phenylene group, a biphenylene nucleus, or a naphthylene nucleus, and R represents a hydrogen atom, a lower alkyl group (such as a methyl group and an ethyl group), a halogenated lower alkyl group, a lower alicyclic group, or A halogenated alicyclic group, etc., and X is an alkylene group such as a methylene group, ethylene group, propylidene group, and isopropylidene group, or an alkylidene group, an aromatic group, or a tertiary amino group (-M(alk)
-), ether group (-O-), carbonyl group (-
CO-) or two or more alkylene or alkylidene groups interconnected by sulfur-containing groups, such as sulfide (-S-), sulfoxide (-SO-) or sulfonyl ( _-SO2- ) groups. show. X may also be an alicyclic group, or a sulfur-containing group, such as a sulfide, sulfoxide or sulfonyl group, an ether group, a carbonyl group or a tertiary amino group. Y is a halogen atom, a nitro group, or a group represented by R' or OR'(R' has the same meaning as R described above), m is from 0 to the number of substitutable hydrogen atoms on X n is an integer from 0 to the number of substitutable hydrogen atoms on the aromatic Ar, p is at least 1
, q is an integer from 0 to 1, and r is an integer (however, when q is 0, r may be 0). In the diphenol shown in the above formula, when there is one or more substituents Y, these substituents may be the same or different. The same is true for R and R'. The substituent Y and the hydroxyl group on the aromatic nucleus may be in the ortho, meta or para position. A mixture of these may also be used. Examples of bisphenols having the general formula above and suitable for carrying out the process of the invention are as follows. Bis(4-hydroxyphenyl)-methane, bis(4-hydroxy-3-methylphenyl)-methane, bis(4-hydroxy-3,5-dichlorophenyl)-methane, bis(4-hydroxy-
3,5-dibromophenyl)-methane, bis(4
-Hydroxy-3,5-difluorophenyl)-
Methane, bis(4-hydroxyphenyl)-ketone, bis(4-hydroxyphenyl)-sulfide, bis(4-hydroxyphenyl)-fulfone, 4,4'-dihydroxydiphenyl ether, 1,1-bis (4-hydroxyphenyl)-
Ethane, 2,2-bis(4-hydroxyphenyl)-propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl) )−
Propane, 2,2-bis(4-hydroxy-3,
5-dibromophenyl)-propane, 2,2-bis(4-hydroxy-3-chlorophenyl)-propane, 2,2-bis(4-hydroxy-3,5
-dichlorophenyl)-propane, 2,2-bis(4-hydroxynaphthyl)propane, 1,1-
Bis(4-hydroxyphenyl)2,2,2-trichloroethane, 1,1-bis(4-hydroxyphenyl)-cyclohexane, 4,4'-dihydroxydiphenyl, 2,2-dihydroxydiphenyl, 2, Dihydroxynaphthalenes such as 6-dihydroxynaphthalene, hydroquinone, resorcinol, 2,6-dihydroxytoluene, 2,6-
Dihydroxychlorobenzene, 3,6-dihydroxytoluene. Functional derivatives of bisphenols are diesters such as diacetate and dibenzoate. Preferred bisphenols are 2,2-bis(4-hydroxyphenyl)-propane and its nuclear halogen-substituted and nuclear alkyl-substituted products. In the present invention, specific examples of trihydric or higher alcohols or functional derivatives thereof used as branching agents include glycerin, trimethylolethane, trimethylolpropane, trimethylolbutane, pentaerythritol, and 1,2,6-hexanetriol. , 1,3,6-hexanetriol, 1,2,5-pentanetriol, sorbitriol, tetrose, pentose, hexose, etc. 3
Typical examples thereof include aliphatic or alicyclic polyhydric alcohols of higher valences, trihydric or higher hydric alcohols of various saccharides, or functional derivatives thereof. 3
Functional derivatives of alcohols with higher valences are the reaction products of alcohols with higher valences than 3 and, for example, aliphatic or aromatic dicarboxylic acids (or functional derivatives thereof), or the reaction products of alcohols with 3 or more hydrides with phosgene (polychloro etc.). Examples include functional derivatives that can be esterified, such as (formate). The branching agent is used in an amount of 0.01 to 5 mol parts, preferably 0.1 to 3 mol parts, per 100 mol parts of the bisphenols. Below the lower limit, the degree of branching is small and the improvement effect on fluidity and stress cracking is not sufficient.
Moreover, if it exceeds the upper limit, the degree of branching becomes large, which deviates from the purpose of the present invention. The present invention does not require any special techniques other than the use of a branching agent, and any known polymerization method can be employed.
Examples include interfacial polymerization, solution polycondensation, and melt polycondensation. The types of dicarboxylic acids, bisphenols, and functional derivatives thereof are appropriately selected depending on each method. Selection of this functional derivative is an easy task in the art. As a preferred polymerization method, an interfacial polymerization method is selected because of the physical properties of the polymer and the fact that polymerization does not require special equipment. Details of the production method by the interfacial polycondensation method are described in, for example, Japanese Patent Application No. 129169/1982, Japanese Patent Application No. 145428/1982, and Japanese Patent Application No. 106534/1973. Although the present invention can be synthesized according to these methods, it goes without saying that it is not limited to these methods, and other known techniques and modifications within the range easily conceived in the art are free. be. An example of an embodiment of the present invention will be explained in more detail using an interfacial polymerization method. In the interfacial polymerization method, aromatic dicarboxylic acid chloride and bisphenols are used as starting monomers. In the interfacial polymerization method, it is preferable that the polyhydric alcohol, which is a branching agent, is reacted with acid chloride, which is a component of the monomer, in advance. The quantitative relationship at this time does not necessarily have to be equal to chemical equivalent, and the total amount of acid chloride used for polymerization may be reacted with a predetermined amount of polyhydric alcohol. There are no particular limitations on the reaction conditions, and they may be appropriately selected. For example, the reaction may be carried out in a molten state without a solvent, or it is also possible to use a solvent. Moreover, in order to speed up the reaction rate, it is also possible to use a dehydrochlorination agent such as a tertiary amine. The reaction product and acid chloride are used as a solution in an organic solvent. The organic solvent is preferably one that has a functional group that is not reactive with acid chloride, is substantially incompatible with water, and is a solvent for the polyarylene ester produced. However, sometimes solvents that are compatible with water or
In some cases, solvents that do not dissolve the polyarylene ester produced are used. Specifically preferred solvents include methylene chloride, chloroform, 1,2-dichloroethane, 1,1,
Halogenated hydrocarbons such as 2-trichloroethane, tetrachloroethane, carbon tetrachloride are commonly used. The concentration of acid chloride in this solution varies depending on the reaction conditions, the type of organic solvent, the solubility of the polyarylene ester produced in the organic solvent, etc., but is usually preferably 2 to 30% by weight. High concentrations of 30% or more are sometimes used. Bisphenols are used as an alkaline aqueous solution, and the concentration is usually preferably 2 to 2.
30% by weight is used. As the alkali for dissolving bisphenols, inexpensive caustic soda is usually used, and the amount of alkali is preferably around the equivalent amount or more than the bisphenols. Since alkaline aqueous solutions of bisphenols tend to become colored when left in the atmosphere for a long time, it is preferable to prepare them in an atmosphere that is protected from air and ultraviolet rays. Furthermore, it is also preferable to use a cyclic agent such as hydrosulfite. Furthermore, in order to produce a polymer with good physical properties such as coloration and mechanical strength, acid chlorides and bisphenols are desired to have high purity. In interfacial polymerization, the molar ratio of acid chloride and bisphenols does not need to be strictly equal, and is selected to be close to equivalent. Further, monovalent phenol, monovalent acid chloride, monovalent amine, etc. are used as the molecular weight regulator. Anionic surfactants such as sodium lauryl sulfate and octadecylbenzenesulfonate, cationic surfactants such as coconut alkyltrimethylammonium chloride and cetyltrimethylammonium chloride, and nonionic surfactants such as polyethylene oxide are used as dispersants during polymerization. May be used. Further, a catalyst for promoting the polymerization reaction may be used, and examples of the catalyst include trimethylbenzylammonium hydroxide, trimethylbenzylammonium chloride, triethylbenzylammonium chloride, triphenylphosphonium iodide, triphenylmethylarsonium Quaternary ammonium salts, quaternary arsonium salts, quaternary phosphonium salts and tertiary sulfonium salts such as iodide, trimethyloctylarsonium iodide, 2-hydroxyphenyldimethylsulfonium chloride or trimethylamine, triethylmethyl, Tertiary amines such as benzylmethylamine and pyridine are used. Polymerization starts with contact between the organic solvent solution and the alkaline aqueous solution, and in order to increase the oil-water contact area, efficient stirring is required. The polymerization temperature is preferably in the range of 0 to 50°C, but in order to increase the polymerization rate, polymerization can be carried out at a higher temperature. The polymerization time is appropriately determined depending on the polymerization conditions. Following the polymerization reaction, an aqueous phase containing alkali chloride and an organic solvent phase of polyarylene ester are separated. This separation can be carried out under standing conditions, by gravity, by mechanical separation using a centrifuge, or by using a demulsifier such as methanol or an inorganic salt. The obtained polymer solution is purified by an appropriate method such as countercurrent extraction or batchwise extraction. The polyarylene ester is isolated from a solution of the purified polymer in an organic solvent. Isolation methods include precipitating the polymer by adding a non-solvent such as alcohol, acetone, toluene, hexane, etc., distilling off the solvent, removing the solvent by spray drying, and contacting it with boiling water or steam. There are several methods, such as a method in which the solvent is concentrated and then left to stand or mixed to form a gel and then taken out. The branched polyarylene ester thus obtained exhibits better fluidity under high shear than the linear polyarylene ester, and also exhibits excellent resistance to stress cracking. Moreover, the polyarylene ester obtained by the present invention can also be blended with other thermoplastic resins. Other thermoplastic resins include addition polymerization type resins such as ABS resin, MBS resin, styrene-acrylonitrile copolymer, rubber-modified styrene resin, or polycarbonate, polyethylene terephthalate, polybutylene terephthalate,
Refers to condensation polymers such as nylon and other thermoplastic resins. Further, pigments,
It is also within the scope of this invention to incorporate stabilizers, inorganic fillers, etc. The present invention will be explained below with reference to Examples and Comparative Examples. Example 1 50.75 g of terephthalic acid chloride, 50.75 g of isophthalic acid chloride, and 0.6 g of trimethylolethane.
Incubate at 80°C for 1 hour. After the reaction is complete, 1500 g of methylene chloride is added to form a solution. On the other hand, 2,2-bis-(4
114 g of -hydroxyphenyl)-propane, 2.82 g of phenol, 42 g of caustic soda, and 0.5 g of trimethylbenzylammonium chloride are dissolved in 2400 g of water. Next, the previously prepared methylene chloride solution is charged into the polymerization tank with vigorous stirring. Stirring was continued for 3 hours while adjusting the internal temperature to 20°C, and then stirring was stopped. After removing the aqueous layer separated into two layers, 2,400 g of water and 10 g of concentrated hydrochloric acid were added to the polymer layer and stirred to wash the polymer layer. Remove the aqueous layer again and wash the polymer layer several times with water. After that, add 500 g of acetone to the polymer layer and continue stirring for a while to precipitate the polymer. The polymer is filtered and then dried. In order to examine the pressure dependence of the fluidity of the branched polyarylene ester thus obtained, the load dependence was examined using a Koka type flow tester (manufactured by Shimadzu Corporation). At the same time, stress cracking test and Vicat softening point were measured. The results are shown in Table-1. For comparison, Table 1 also shows the measured values of a linear polyarylene ester produced in the same manner as in Example 1 except that no branching agent was used.

[Table] As is clear from Table 1, when compared to linear polyarylene ester, branched polyarylene ester has no change in fluidity at low loads, but exhibits good fluidity at high loads, resulting in a decrease in melt viscosity. It can be seen that it is highly pressure dependent. It also has improved stress cracking resistance. Furthermore, fluidity has been improved without reducing heat resistance.

Claims (1)

[Claims] 1. When producing polyarylene esters from aromatic dicarboxylic acids or ester-forming derivatives and bisphenols or their ester-forming derivatives, trihydric or higher alcohols or their ester-forming derivatives are added per 100 mole parts of bisphenols. 1. A method for producing a branched thermoplastic polyarylene ester which exhibits high pressure dependence of melt viscosity and good fluidity, characterized by carrying out a condensation reaction by adding 0.01 to 5 mol parts.