JPS6111967B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is directed to a novel family of crystalline, easy-to-handle, linear aromatic polyesters of improved fire safety performance comprising repeating units derived from 1,2-bis(hydroxyphenyl)ethane and derivatives derived therefrom. Concerning molding powders and molded articles. Since the first practical development of such polymers by Messrs. Winfield and Dexon, many polyesters have been proposed for use as molding resins and industrial thermoplastics. Although some such polyesters and copolyesters have had commercial success as films and textile products, most have been unsuccessful as molding resins and industrial thermoplastics. Two relatively successful classes, polyethylene terephthalate and polytetramethylene terephthalate prepared from aliphatic diols and terephthalic acid, have certain deficiencies as industrial thermoplastics. They are both highly flammable and have rather low glass transition temperatures that limit their usefulness only to relatively low temperatures. U.S. Pat.
Discloses a method for producing polyester by reacting diphenol with an aromatic carboxyl dihalide at a temperature of 1.5 or higher. Preferred polyesters are hydroquinone and isophthalic acid, and resorcinol and terephthalic acid, and in which a portion of the hydroquinone or resorcinol is replaced with another dihydric phenol and a portion of the isophthalic acid or terephthalic acid is replaced with another dicarboxylic acid. derived from a cocondensate. This U.S. patent describes the process as an aromatic carboxyl dihalide with the general formula This suggests that it can be used to react with a very wide group of dihydric phenols. However, the instability of alkylene-bridged diphenols at such high reaction temperatures in the presence of hydrogen halides would inhibit the formation of polyesters of sufficient molecular weight and acceptable color, and indeed such The decomposition of such polyesters under harsh reaction conditions has been confirmed in Belgian Patent No. 766806. U.S. Pat. No. 2,595,343 teaches a more satisfactory process for making polyesters from phenols by reacting diacetates of diphenols with dicarboxylic acids. Polyesters made from diphenols and aromatic dicarboxylic acids are generally useful at higher temperatures because of their higher softening temperatures.
However, as long as they do not contain flame retardants that produce toxic exhaust gases containing nitrogen, sulfur, phosphorus or halogens, they are also quite easy to use, especially if they are in the form of thin sheets or filaments. It is flammable. Such polyesters include bisphenol A [2.
2'-bis(4-hydroxyphenyl)propane]
and 1,1-bis(4-hydroxyphenyl)
Examples include polyester of ethane. Furthermore, many polyesters such as hydroquinone, 4,4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)methane, and other polyesters have extremely high softening points, often above 400°C.
and is therefore thermally unstable in the melt,
Moreover, it is difficult to handle at normal processing temperatures, making it impractical for normal processing. FR 2006477 discloses new 1,4-dicarboxy-1,4-dialkylcyclohexanes and polymers prepared therefrom. Among the polymers are 1,2-bis(4-hydroxyphenyl)ethane and the cycloaliphatic acid 1,4-dimethylcyclohexane-1.
There are flammable polyesters made from 4-dicarboxylic acids. Kolesnikov et al. disclose polycarbonates and mixed polycarbonates of 1,2-bis(4-hydroxyphenyl)ethane [Polymer Science.A.USSR 9 . 764～773
(1976)], but there is no disclosure regarding whether or not it has flame retardancy. Therefore, there is a need in the art for a relatively high glass transition temperature that is flame retardant without the addition of toxic flame retardant elements such as halogens and phosphorus, and that makes it useful at temperatures above about 100°C. There is a need for industrial thermoplastic polyesters having a In a review of methylene-crosslinked diphenol polyesters in Industrial and Engineering Chemistry, Vol. 51, p. 147 (1959), Mr. Andre Koniks reports 29 types of diphenol polyesters. Only two types [bisphenol A terephthalate and bisphenol A/benzophenone-4,4-dicarboxylic acid] are crystalline, and the third amorphous form (bisphenol A isophthalate) is produced by solution forming technology. It has been found that it can be obtained from solution in a semi-crystalline state.
Mr. Koniks acknowledges that the influence of chemical structure on physical properties such as crystallinity is quite complex and not easily predictable. In US Pat. No. 3,448,077, Koniks teaches that polyesters obtained from aromatic dicarboxylic acids and diphenols are amorphous but can be crystallized by heat treatment. Therefore, it has a relatively high melting point to provide high temperature strength, but not so high that it becomes difficult to handle or melt and decompose, and crystallizes quickly so that normal molding can be achieved with rapid molding cycles. There is a need for polyester industrial thermoplastics that can be molded on equipment. Additionally, there is a need for polyester industrial thermoplastics that have a high degree of crystallinity, solvent and reagent resistance, and dimensional stability for molding and molded articles. Additionally, there is a need for rapidly crystallizable crystalline polyester technical thermoplastics with improved thermal stability performance without the addition of toxic flame retardant elements such as nitrogen, sulfur, phosphorus or halogens. Polyesters and copolyesters derived from aromatic diphenols have been discovered that have a combination of strength, processability, high temperature performance, improved fire safety performance and crystallinity. This preferred group of compounds has rapid crystallization rates and solvent resistance and imparts dimensional stability to molded or molded articles made therefrom. This combination of properties is due to the fact that the aromatic dicarboxylic acid and the hydroxyl
This is accomplished using a polyester condensate with 1,2-bis(hydroxyphenyl)ethane or mixtures thereof in the position or 4 position. This component acid and diphenol have a polyester melting point of approximately 350
℃ or less, and preferably so that its glass transition temperature is about 100℃ or higher. The component acids of crystalline polyester are isophthalic acid,
Terephthalic acid, 3·3′-, 3·4′- and 4·
4'-Bibenzoic acid, 1, 3-, 1, 4-, 1, 5
-, 1,6-, 1,7-, 1,8-, 2,6- and 3,7-naphthalene dicarboxylic acids and formulas (where the carboxyl group is in the 3rd or 4th position and X is O, S, SO ₂ , C=O, CH ₂ or
CH ₂ CH ₂ ). Diphenol is 1,2-bis(hydroxyphenyl)
Ethane and optionally resorcinol, hydroquinone, 3.3'-, 3.4'- and 4.4'-diphenols, 1.3-, 1.4-, 1.5-, 1.
6-, 1.7-, 1.8-, 2.6- and 2.
7-dihydroxynaphthalene and formula Diphenols selected from the group consisting of diphenols represented by: in which the hydroxyl group is in the 3 or 4 position and Y is O, S, SO ₂ , C=O, CH ₂ or (CH ₂ ) ₃ Both include one type of diphenol. This polyester can be ground to produce a molding powder, which is easily molded or extruded into useful articles having desirable properties, particularly improved fire safety performance. By selecting crystalline aromatic polyesters of 1,2-bis(hydroxyphenyl)ethane that crystallize quickly, they can be molded on conventional molding equipment with rapid molding cycles and molds made therefrom. Alternatively, it is a feature of the present invention that solvent resistance and dimensional stability can be imparted to molded articles. Therefore, it is an object of the present invention to select a combination of aromatic dicarboxylic acid and diphenol containing sufficient 1,2-bis(hydroxyphenyl)ethane to obtain a polyester with improved fire safety performance and crystallinity. It is a characteristic of
The choice of this dicarboxylic acid-diphenol combination was such that the melting point of the polyester was approximately 350°C to allow for easy processability without decomposition.
and 100 by capillary rheometer.
The melt viscosity measured at 350°C at a shear rate of sec ^-1 is less than 10 ⁵ poise and its glass transition temperature is preferably about 100°C or higher to provide high service temperatures. . The polyesters of the present invention may be prepared in any convenient manner, such as by melt condensation or solution condensation of mixtures of aromatic dicarboxylic acids and diphenolic diesters selected to provide desirable fire safety performance and processability. can. They can be prepared by melt or solution polymerization of phenolic esters of aromatic dicarboxylic acids and selected mixtures of diphenols or by interfacial polymerization of salts of diphenols and aromatic dicarboxylic acid dihalides. That is, although this combination is formally a condensation product of a diacid and a diphenol, in reality the reaction components are a diacid and a diphenol ester, or a phenyl ester of a diacid and a diphenol, or a salt of a diphenol. and diacid halide. A preferred method of production is the melt condensation of an aromatic dicarboxylic acid and a diphenol diester mixture. A suitable process for the production of polyesters is carried out in the melt phase and optionally using any catalyst commonly used for such acid decompositions, such as alkali metal hydroxides, phosphates, carbonates or alkanoates, titanium dioxide, orthotitanic acid. It consists of reacting a mixture of _C1 - _C7 aliphatic monocarboxylic acid diesters of diphenols with at least one aromatic dicarboxylic acid in the presence of a salt and an organotin compound.
Alkali metal salts are generally the preferred catalysts. This catalyst can be used in varying amounts from 0.5 to 5.0 mole percent of the reactants. Preferably, however, the amount of catalyst used is from 1.0 to 2.5 mole % of the reactants, and more often about 2 mole %. The reaction takes place in an inert atmosphere that is substantially free of oxygen and has between 1 and 7 carbon atoms formed during the reaction.
The process is carried out under temperature and pressure conditions such that the aliphatic monocarboxylic acids are separated from the reaction mixture by distillation. Diphenol diesters useful in this melt condensation process include relatively low boiling monocarboxylic acids having 1 to 7 carbon atoms, such as acetic acid, propionic acid, butyric acid, pentanoic acid, hexanoic acid or heptanoic acid, or mixtures thereof. can be given. Most preferred is acetic acid. More particularly, the preferred polycondensation process conveniently comprises a _C1 - _C7 aliphatic carboxylic acid ester mixture of diphenols in which the reactants are substantially stoichiometric with up to a 10 mole percent excess of diester or diacid. contacting the aromatic dicarboxylic acid mixture in proportion and in the presence of a catalyst. The reaction temperature is usually between 240°C and 350°C, and the pressure is at or below atmospheric pressure. Generally the reaction is carried out in an inert atmosphere and at atmospheric pressure in the initial phase, and then substantially all of the _C1 - _C7
This is carried out at a substantially higher temperature and at a lower pressure or a series of lower pressures until the aliphatic carboxylic acid is removed by distillation and the polyester product is of high molecular weight. For adequate strength in polyester, the molecular weight of this polyester must be 60 parts by weight of phenol and 40 parts by weight of synthetic.
Solution in a mixed solvent containing tetrachloroethane
It is preferably sufficient to give an inherent viscosity of at least about 0.3, preferably at least about 0.5, when measured at 30°C at a concentration of 0.5 g per 100 ml. 1,2-bis(hydroxyphenyl)ethane can exist in several isomeric forms, such as the 4,4'-3,4'- and 3,3'-isomers, depending on the position of the hydroxyl group. . 25% for the purposes of this invention
4,4'-isomer mixtures or blends containing up to 3,4'- and 3,3'-isomers provide highly useful polyester compositions within the scope of this invention. I can do it. However, the amount of 3,4'- and 3,3'-isomers is approximately 10 mol%.
is preferred and substantially pure 4,4'-isomer is often used. The fire safety performance of polymers is demonstrated in several ways, including flame resistance or resistance to ignition or flame spread, smoke production on combustion, and toxic gas production on combustion. Polymers with improved fire safety performance are those that are difficult to ignite, do not easily spread flames, produce little smoke on combustion, and are very often free from combustion products of common flame retardant materials. , which emit less toxic gases than those containing nitrogen, sulfur, phosphorus, or halogens. Flame resistance is conveniently measured by Underwriters Laboratories, ``Test Method for Flammability of Plastic Materials,'' UL-94, published February 1, 1974. A test sample conforming to the specified dimensional limits is ignited, after which the ignition flame is removed and the time required for both the flame combustion and any subsequent flameless combustion to be extinguished is measured. The samples were tested in an order of decreasing flammability depending on the time of flame or flameless combustion and whether molten drips from the sample ignited cotton fibers placed below the sample. Classified as 0. A rating of - only indicates that the solid polymer is self-extinguishing within an average of 25 seconds after removal of the ignition flame, based on 5 trials. Melt dripping from the burning sample may ignite untreated cotton fibers placed 12 inches (30 cm) below the sample. Samples of - quality are self-extinguishing within an average time of 25 seconds after removal of the ignition flame and do not drip burning melt that could ignite cotton placed 30 cm below the sample. All localized flames must be extinguished within 60 seconds after removal of the second test flame, must not migrate to the support clamps, and must not ignite the surgical cotton. Other - If the requirements are met, i.e. the flame is extinguished within an average of 5 seconds after ignition, no flame particles are present and the flame is extinguished within 30 seconds after the second removal of the test flame. The sample is rated -0.
For a more complete description of the evaluation system used for the UL-94 test method, please refer to Underwriters Laboratories publications. However, these numerical flame spread ratings are not intended to reflect the risk posed by such materials under actual fire conditions. The test samples were of three thicknesses approximately 0.32cm, 0.16cm and 0.08cm.
15 cm x 1.3 cm, and these are held in a vertical position during the test. The minimum sample thickness for a -0 or - rating is determined by testing. Other tests used to evaluate the flame resistance of polymers include the oxygen index test measured according to ASTM D-2863-70 and various flux tests. In this case, 0.16 cm thick samples are exposed to ignition sources of various heat fluxes for various times and the time to flame extinguishment is noted. Smoke generation is ASTM Special Technical Publication
422 (1969) using the maximum specific optical density method.
Measured using Aminco NBS smoke camber using 0.08 cm thick samples. Unexpectedly, polyisophthalate of 1,2-bis(4-hydroxyphenyl)ethane, which does not contain any conventional flame retardant additives, in tests on samples 0.08 cm or less thick, Gives a flammability rating for V-O. In contrast, glass-filled poly(1,4-butylene terephthalate) did not satisfy the evaluation at a thickness of 0.30 cm, and polyisophthalate of 2,2-bis(4-hydroxyphenyl)propane Thicknesses of 0.19 or less do not satisfy the - rating. Polymers generally rate higher when they are thicker. 1・
The combination of 2-bis(4-hydroxyphenyl)ethane and 2.2-bis(4-hydroxyphenyl)propane is intermediate between the extreme values for both homopolymers. In addition to its excellent flame resistance,
1,2-(Hydroxyphenyl)ethane can produce aromatic polyesters that produce less smoke when burned and do not produce toxic exhaust gases containing nitrogen, sulfur, phosphorus or halogens. That is,
Aromatic polyester of 1,2-bis(hydroxyphenyl)ethane can be used without the addition of usual flame retardants.
It has unexpectedly excellent fire safety performance. And the introduction of 1,2-bis(hydroxyphenyl)ethane into the polyester condensate of aromatic dicarboxylic acid and diphenol improves the fire safety performance of the polyester condensate in one or more aspects. Although small amounts of 1,2-bis(hydroxyphenyl)ethane into the polyester condensate can provide improved fire safety performance, at least 60 mole % and even more preferably at least 75 mole % of the polyester repeat units.
is preferably derived from 1,2-bis(hydroxyphenyl)ethane to achieve a more significant improvement in fire safety performance. Besides providing improved fire safety performance, the combination of aromatic dicarboxylic acids and diphenols, including 1,2-bis(hydroxyphenyl)ethane, also affects the morphology of polyester condensates. You can choose. The expression "amorphous" is used in its conventional sense to mean that the polymer has a relatively low degree of molecular order and is generally isotropic and optically transparent. In contrast, the expression "crystalline" means that the polymer has a relatively high degree of molecular order and that a 10 mg sample was molten in a nitrogen atmosphere at a rate of 20°C/min using a Perkin-Elmer differential scanning calorimeter model DSC6-1B. This means that when cooled, it shows a sharp peak corresponding to the heat of crystallization. Many polyester combinations may be crystalline in nature, but are difficult to crystallize, and this converts to a metastable amorphous state at temperatures ranging from room temperature to their glass transition temperature or above. can be retained. This polymer is
It is considered easy to handle if it softens or melts and flows at temperatures of 350°C or less. The criteria for determining ease of handling or processability are
Melt viscosity measured on a capillary rheometer at a shear rate of 100 ^s . For sufficient processability, aromatic dicarboxylic acids or mixtures thereof and 1.
The polyester combination with 2-bis(hydroxyphenyl)ethane or mixtures thereof has a temperature of about 10 ⁵ at 350°C.
It should be selected to provide a melt viscosity of less than 100 poise and preferably in the range of about 10 ² to 10 ⁵ poise at a temperature range of 200° to 320°C. The combination is also selected to provide a high usable temperature for the polyester, preferably a glass transition temperature of about 100°C or higher and more preferably about 140°C or higher. The novel 1,2-bis(hydroxyphenyl)ethane polyesters and copolyesters of this invention are useful in many forms and can be shaped in many ways to produce useful objects.
They can be formed into high strength films from the melt or from solution in a suitable solvent such as a mixture of phenol and tetrachloroethane. Those that can be oriented under stress can be melt spun and drawn into fibers of good strength. They are very useful as molding resins for the manufacture of molded articles. The new polyester can be ground to a powder or extruded and pelletized, and the powder or pellets can be extruded into bar or rod form. They can be injection molded into any desired shape using conventional molding equipment or machines. A suitable injection molding operation for this new 1,2-bis(hydroxyphenyl)ethane polyester is a screw-fed injection molding machine;
In this case the stock is held at a suitable temperature to provide the appropriate melt viscosity for molding and the mold is maintained at a temperature in the range of about 10-30°C below the glass transition temperature, and preferably about 20°C below the glass transition temperature.
kept at a low temperature. Any other convenient injection molding and extrusion equipment and operations may be used with the 1,2-bis(hydroxyphenyl)ethane polyesters and copolyesters as well. For use as a molding resin, the new polyester may be supplemented with any of the conventional additives commonly used in conjunction with molding resins, including waxes, lubricants, dyes, pigments, flame retardants, gloss modifiers, and others. can be mixed or contained. Many such additives are known in the molding resin art. Their use in combination with 1,2-bis(hydroxyphenyl)ethane polyester molding resins can give advantageous results. For example, thermal stabilizers minimize high temperature decomposition and allow the polyester to be processed at such high temperatures for longer periods of time. In molding applications, polyesters are preferably rapidly crystallized so that they can be molded on conventional molding equipment with rapid molding cycles. Accordingly, in a preferred embodiment of the invention, the bis(4-hydroxyphenyl)ethane or mixture thereof and the aromatic dicarboxylic acid or mixture thereof are selected to provide the desired or rapid crystallization properties. The polyester of the present invention is crystalline and melts at temperatures below about 350°C upon condensation with 1,2-bis(hydroxyphenyl)ethane or a diphenol mixture containing 1,2-bis(hydroxyphenyl)ethane. such as producing polyester,
Prepared from suitable aromatic dicarboxylic acids or acid mixtures. Preferred acids are isophthalic acid, terephthalic acid, 3.3 ¹ -, 4.4 ¹ - and 4.4'-bibenzoic acid, 1.3-, 1.4-, 1.5-, 1.6
-, 1.7-, 1.8-, 2.6- and 2.7
- naphthalene dicarboxylic acid and formula (where the carboxyl group is in the 3rd or 4th position and X is O, S, SO ₂ , C=O, CH ₂ or
CH ₂ CH ₂ ). Preferred acids include isophthalic acid, terephthalic acid, bis(4-carboxyphenyl)ether,
bis(4-carboxyphenyl) sulfide,
Bis(4-carboxyphenyl)sulfone, bis(4-carboxyphenyl)methane, 1,2-bis(4-carboxyphenyl)ethane and 2.
2-bis(4-carboxyphenyl)propane is mentioned. This is because these acids and acid mixtures can be easily combined with diphenol mixtures to produce polyesters with desired melting points, glass transition temperatures (Tg), and crystallization rates. A particularly preferred aromatic dicarboxylic acid is isophthalic acid and mixtures thereof. one or more of these diacids and a small amount, generally about 25
Mixtures with up to about 10 mole percent of _C2 to _C20 aliphatic diacids and more preferably up to about 10 mole percent of _C7 to _C12 aliphatic diacids can be used. Generally, the amount of aliphatic diacid is chosen to provide improved processability without significant loss in the Tg and melting point of the resulting polyester. Preferably this amount is limited to a Tg loss of no more than 10°C. The polyester is a polyester which is melted from 1,2-bis(hydroxyphenyl)ethane mixed with the dicarboxylic acid and optionally any suitable diphenol at a temperature below about 350°C and crystallizes rapidly when cooled. It is manufactured in such a way that it produces Preferred optional diphenols include resorcinol, hydroquinone,
3.3 ^1- , 3.4′- and 4.4′-diphenol, 1.3-, 1.4-, 1.5-, 1.6-,
1,7-, 1,8-, 2,6- and 2,7-dihydroxynaphthalene and formula (wherein the hydroxyl group is in the 3rd or 4th position and Y is O, S, SO ₂ , C=O, CH ₂ or C
It includes at least one diphenol selected from the group consisting of diphenols represented by ( _CH3 ) ₂ ). Preferred diphenols include bis(4-hydroxyphenyl)methane,
2,2-bis(4-hydroxyphenyl)propane, bis(4-hydroxyphenyl)ether,
Bis(4-hydroxyphenyl)sulfide and bis(4-hydroxyphenyl)sulfone are mentioned. A more preferred rapidly crystallizing combination of aromatic dicarboxylic acid and diphenol contains isophthalic acid as the major molar component of the acid moiety. Furthermore, in preferred combinations at least 75 mole% of the diphenol moiety is 1,2-bis(4-hydroxyphenyl)ethane, and even more preferably it is at least 90 mole%, and even more preferably it is It is 95-100 mol%. The reasons for this preference are the availability and cost of the acid and the desirable glass transition temperature and melting point of the resulting polyester. In conclusion, one of the more preferred combinations is obtained from isophthalic acid and 1,2-bis(4-hydroxyphenyl)ethane without additional components. However, when mixtures of other aromatic diacids with isophthalic acid are used, such other diacids have little effect on the crystallization rate up to 33 mole percent. However, some changes in glass transition temperature and melting point occur. Similarly,
When mixtures of 1,2-bis(4-hydroxyphenyl)ethane and other diphenols are combined with isophthalic acid, such other diphenols have little effect on the crystallization rate up to 10 mol%. do not have. However, some changes in glass transition temperature and melting point occur. Because the molding cycle is preferably rapid, it is desirable for the crystalline polyester to crystallize during the short time that the polymer is cooling in the mold. That is, molding materials for applications where high temperature dimensional stability is important need to have a rapid crystallization rate. Crystallization rates can be measured by differential scanning calorimetry, and throughout this specification when crystallization rates are given, rates determined by this technique are used. It is expressed as the reciprocal of the time required for half the heat of crystallization observed when the sample is cooled at a rate of 20°C per minute. The equipment used for crystallization rate measurements is a DSC-1B Thermal Analyzer (manufactured by Perkin-Elmer), and the use of this equipment is described in "Instructions Differential
"Scanning Calorimeter" (Perkin-Elmer Company)
Published in November 1966), pages 7-9. In measuring the crystallization rate, the following method is used. The equipment and recorder are turned on and set in the stand-by position and allowed to warm up for approximately half an hour. The device is then fully calibrated for differential and average temperatures as indicated in the Perkin-Elmer Instruction Manual. Approximately 5-10 mg of polymer sample is grasped into a non-sealable pan and lid with an encapsulation tool, ensuring the bottom is flat. The empty non-sealable pan and lid are grasped in the same manner. Place the sample and reference into the right and left sensors of DSC-1B. Place the sample cover in position and adjust the nitrogen flow to approximately 0.05 SCFH (1.42/hr). DSC−
The 1B range was set to 4 mcal/sec, the scan rate was set to 10°C/min, and the recorder chart speed was set to 2.54 cm/min. The zero point of the machine is
The recorder pen is adjusted to the appropriate position on the cart. The recorder is then turned on and the baseline is recorded at room temperature. The green indicator light on the machine indicates temperature control and the recorded baseline will be level when thermal equilibrium is reached between the sample and the machine. The program toggle switch is then placed in the up position and the sample is scanned upward at a constant rate of 10°C/min to approximately 10°C above the endothermic melting peak. Then place the toggle switch in the neutral position and leave for 2 minutes. While keeping the sample isothermal for 2 minutes, reset the scan speed dial to 20°C/min and increase the recorder speed to 5.08/min.
Set to cm. Place the program toggle switch in the reduced position and allow the sample to cool at a constant rate of 20°C per minute. A green indicator light on the machine indicates that the temperature is under control. Exothermic crystallization peaks can be seen on the recorder thermogram if crystallization occurs within the scan time. Continue this scan until past the peak to reestablish the baseline and complete the thermogram. A typical exothermic crystallization peak is shown in FIG. Interpolate the baseline of the thermogram on either side of the crystallization peak. The baseline may exhibit a curve depending on the device. In that case, an appropriate French waveform must be used for interpolation. The point where the baseline first deviates and forms a peak [S]
and also determine the point [E] where the peak (final peak) ends and coincides with the baseline again. The former indicates the starting point, while the latter indicates the end point of the crystallization process. Dropping perpendicular lines from points [S] and [E] cuts the temperature axis of the thermogram at T _S and T _E , respectively. The total area [A] defined by [S] and [E] under the peak is measured with an area meter. Area [A] is proportional to the heat of crystallization of the sample. The total time required for crystallization is T _S - T _E /cooling rate (min) = T _S - T _E /20
(minutes) is given by. The peak whose total area [A] was measured is drawn from different points on the peak [Bi], and the interpolated baseline is set to [Ci], and the thermogram is plotted at 4°C intervals [T _ci et al.]. Cut into several segments by cutting the temperature axis. The area [A′] of each segment [SB ₁ C ₁ , SB ₂ C ₂ ] is determined using an area meter, and the corresponding crystallization time is counted. T _s −T _ci /cooling rate (min)=T _s −T _ci /2
0 (min) etc. Divide the area of each segment by the total area of the peak [A] and express the result in %. The % crystallization peak area is plotted against crystallization time. half time, that is, [A′] at that point is 50% of [A]
Establish the time from the graph. The crystallization rate of the sample is the reciprocal of this "half time." For example, if the half time is 5 minutes, the reciprocal is 0.2 minutes ^-1 . Therefore, "crystallization rate" as used herein refers to the DSC-1B thermal as described above using a cooling rate of 20°C/min unless a different cooling rate is stated. It is understood to be the velocity measured on the analyzer. Crystallization rates of about 0.2 min ^@-1 or greater, as measured by this method, are satisfactory for injection molding of polymers. This is because the cooling rate in the molding operation is generally much more rapid than the cooling rate used for crystallization rate measurements. However, crystallization rates of about 0.5 min ^-1 or more are more preferred, and for rapid molding cycles, crystallization rates of about 1 min ^-1 or more are even more preferred. In addition to selecting a rapidly crystallizing polyester and an aromatic dicarboxylic acid and diphenol combination containing sufficient 1,2-bis(hydroxyphenyl)ethane to provide a melting point below about 350°C, this combination is preferably selected to provide a glass transition temperature of about 100° C. and preferably at least about 140° C. or higher so that the polyester exhibits sufficient resistance to both short-term and long-term stress;
and a temperature of about 100°C or above and preferably 140°C
It should exhibit dimensional stability at temperatures above. 200°C, although the melting point should be below about 350°C.
It is preferably in the range of about 200 DEG to 320 DEG C. in order to provide the opportunity to produce filled polyesters with good strength at temperatures of DEG C. and above. More preferably, the melting point should be in the range of about 250°C to 300°C for high temperature strength without causing excessive thermal decomposition in the melt. The glass transition temperature and melting point of polyester are measured using a Perkin-Elmer differential scanning calorimeter model DSC-1B.
Measured using The machine is calibrated, the sample and reference samples are prepared and the nitrogen flow rate is set as described for crystallization rate measurements. The device is programmed to heat at a rate of 20°C/min. The center point of the first discontinuous point in the thermogram is taken as the glass transition temperature [Tg]. The thermogram may show a crystallization exotherm. and from the glass transition temperature about
A melting endotherm is observed above 150°C. The main peak of the endotherm is taken as the melting point (Tm). In addition to improved fire safety performance, the crystalline 1,2-bis(hydroxyphenyl)ethane polyesters of the present invention are notable for several special features. For example, the most preferred poly[1,2-bis(hydroxyphenyl)ethane isophthalate]
The crystallization rate of can be faster than that of nylon 6, (polyepsilon caprolactam) and polytetramethylene terephthalate. Polyesters and copolyesters in which 1,2-bis(hydroxyphenyl)ethane is in the range of about 90 to 100 mole percent of the diphenol moiety are typically 250
It has a melting point in the ~320°C range and a high glass transition temperature, or Tg, in the approximately 110-180°C range. These properties provide high heat distortion temperatures and creep resistance for the various shapes molded from these polyesters. This polyester is also
It also has high thermal stability as shown by thermogravimetric analysis without appreciable weight loss up to temperatures above 450°C. It has been discovered that the crystalline polyesters of the present invention have excellent resistance to attack by chemical reagents. They show negligible weight loss after long-term exposure to non-polar media and polar solvents such as hexane, trichloroethane, acetone and methyl ethyl ketone. They also resist acid, base and water attack. Similarly, they do not exhibit environmental stress cracking when exposed to these solvents as molded specimens.
The water absorption of 1,2-bis(hydroxyphenyl)ethane is generally low. For example, poly[1,2-bis(hydroxyphenyl)ethane isophthalate]
Even for low molecular weight samples, the water uptake of
It is 0.2-0.3% by weight. The present invention will be further explained by examples, but the present invention is not limited thereto. The monomer ratios herein are molar ratios and all other parts and percentages are by weight unless otherwise specified. The examples illustrate the preparation of the 1,2-bis(hydroxyphenyl)ethane polyester of the present invention and its unexpected properties. All inherent viscosities are measured at 30° C. in a phenol/syn (symmetrical) tetrachloroethane mixed solvent system containing 60 parts by weight of phenol at a concentration of 0.5 g per 100 ml. Polymer morphology and fire safety performance have been determined by the methods described above. The stress cracking properties of this polyester are measured using a specially designed test method. In this case 0.8
A sample piece measuring 6 mm x 24 mm is cut from a mm thick polymer film. Fold this piece in half and stabilize the ends together so that the center is under mild stress. Weighing this double-folded and stabilized piece and immersing it in the test solvent and immediately observing the condition of the sample,
Then, observe them every 24 hours for the next 3 days. The amount of solvent absorbed is determined by weighing samples at 1, 4 and 16 day intervals. In extreme cases, the specimen has no stress cracking resistance and immediately fractures. Such tests are reported as "failed." In less extreme cases, failure occurs after a number of days and this is recorded as such in Table 3. In less severe cases, cracks are observed but no further changes occur. Such test results are reported as "cracked". However, some samples show no breakage or cracking after the test is completed. And such are indicated as "passed". These are the crystalline polyesters of the invention. Example 1 Production of poly[1,2-bis(4-hydroxyphenyl)ethane isophthalate] 8.2 parts of isophthalic acid and 1,2-bis(4-
A charge consisting of 14.8 parts of acetoxyphenyl)ethane is charged to a reaction vessel equipped with a stirrer, a condenser and a receiver. The vessel is evacuated and purged with nitrogen three times. A nitrogen blanket is maintained in the reactor and heated to 250 DEG C. for about 3 hours, during which time about 3.5 to 4.0 parts of acetic acid are distilled out. At that time, the container was evacuated to a pressure of approximately 125 mm, and the heating at 275°C was reduced to 1/2.
If this continues for 2 hours, an additional 1 to 1.5 parts of acetic acid will be distilled out during that time. Next, increase the vacuum level to approximately 0.1 to 0.2
mm and the temperature is increased to 290° C. for an additional hour. At this point, the reaction mixture becomes so viscous that further stirring is difficult. Heating is discontinued and the reaction mixture is placed back into the nitrogen blanket and allowed to cool. The resulting polymer is pale yellow crystalline and exhibits an inherent viscosity of 0.57 in phenol/tetrachloroethane solvent. Example 2 Preparation of poly[1,2-bis(4-hydroxyphenyl)ethane isophthalate] A similar reaction was carried out under the same reaction conditions as in Example 1, using the same reaction components and the same equipment. , but after the first 3 hours of reaction time, the temperature is increased to 275° C. and the pressure is decreased to 125 mm for 30 minutes. The temperature is then increased to 290° C. during the final reaction time in a high vacuum of 0.1-0.2 mm. The resulting polymer has an inherent viscosity of 0.83, and is crystalline, transparent, and light yellow in color. Examples 3-16 Examples 3-16 were carried out using mixtures of diphenol diacetate and isophthalic acid according to the method of Example 1 above, adjusting the temperature and heating cycle to suit the rheology and morphology of the particular polyester. be done. The composition and physical properties of the polyester are shown in Table 1 below. -hydroxyphenyl)propane is mentioned for comparison. Melt viscosity was measured using a Sieglaff-McKelvey rheometer at 316°C using a capillary tube with a length-to-diameter ratio of 25:1.
Rheometer) at a shear rate of 100 s ^-1 .

【table】

Table of Contents Examples 17-23 A series of polyesters are prepared by the method of Example 2 above by adjusting the reaction temperature and heating cycle to suit the rheology and morphology of the particular polyester. In comparing polyesters, flame resistance is graded by the Limiting Oxygen Index. The local oxygen index values are shown in Table 2 below and compared to the local oxygen index values of other polyesters such as polyethylene terephthalate, BPA isophthalate and BPA oxydibenzoate, polycarbonate and polysulfone. In Table 2, the local oxygen index is measured on a 62.5 mil (1.56 mm) flat plate and an 8 mil (0.2 mm) film, both reinforced with 14 g/m ² weight glass wool. The data presented are relative to several other polyesters and engineered thermoplastics.
Demonstrates superior flame resistance of BHPE polyester.

[Table] Flake polyester)

[Front] Made by Poration)
Table 3 below lists the data obtained by the UL-94 test and shows that the polyester containing 1,3-bis(4-hydroxyphenyl)propane (Example 16) and a substantial proportion of bisphenol A Figure 2 shows the superior flame resistance of the polyester of 1,2-bis(4-hydroxyphenyl)ethane, especially in thin sections, when compared to (Examples 9, 10, 11 and 14). AFOT values in the table and
AAGT values are according to UL Standard 94 (Underwriter Laboratory Standard). Briefly, the sample piece was placed at an angle of 20 to the vertical direction at the tip of the blue center (height 38mm) in the burner flame (height 127mm).
AFOT (Flame out time)
time) and the time for flameless combustion to be AAGT (after glow time).

【table】

[Table] Examples 25-28 A series of polyester combinations of 1,2-bis(4-hydroxyphenyl)ethane and a mixture of isophthalic acid and 5-tert-butyl-isophthalic acid were prepared using the method of Example 2 above. and evaluated by the UL-94 test described above. The data obtained shows that a V-0 rating is obtained with a polyester sample approximately 0.08 cm thick.

Table of Contents Examples 29-41 Still other polyester samples are made by the method described in Example 2 above by adjusting the reaction temperature and heating cycle to suit the particular polyester. In Example 31, 0.5% by weight of titanium dioxide catalyst is used. In Examples 32-35, the diacid filler is expressed in mole percent of another diacid including terephthalic acid, 2,6-naphthalene dicarboxylic acid, and bis(4-carboxyphenyl)ether (oxydibenzoic acid). amount as a mixture with isophthalic acid. In Example 38, a polyisophthalate mixture of 90 mol% 1,2-bis(4-hydroxyphenyl)ethane and 10% bis(4-hydroxyphenyl)sulfide is produced. Table 5 below shows the inherent viscosity, physical properties, glass transition temperature, and melting point. The data in Table 5 shows a high level of 1.
Polyester combinations containing acids such as 2-bis(hydroxyphenyl)ethane and isophthalic acid are opaque and exhibit crystalline melting points below 300°C (see Examples 29-38, 10, 25, 26); ,
In contrast, another diphenol (Example 9,
Example 27 ,
28) indicates that it is amorphous or difficult to handle.

【table】

TABLE The crystallization rate of a series of polyesters of 1,2-bis(hydroxyphenyl)ethane is determined by the method described above using a Perkin Elmer differential scanning calorimeter model DSC-1B. The data obtained are shown in Table 6 below, and show that it is possible to achieve a crystallization rate superior to that of polytetramethylene terephthalate and nylon 6, and that 1,2-bis It has been shown that small amounts of diphenols such as bis(4-hydroxyphenyl) sulfide mixed with (4-hydroxyphenyl)ethane have no appreciable effect on the crystallization rate of polyesters made therefrom. It can be done.

[Table] Solvent resistance and stress cracking resistance of crystalline polyisophthalate of 1,2-bis(4-hydroxyphenyl)ethane and amorphous polyisophthalate of 2,2-bis(4-hydroxyphenyl)propane Comparative data regarding gender are shown in Tables 7 and 8 below.

【table】

[Table] Natsuta
37 〃 〃 〃 Unmeasurable
42 Cracks Unmeasurable Unmeasurable 〃
According to the data shown in Tables 7 and 8 above, the crystalline polyester of 1,2-bis(4-hydroxyphenyl)ethane is poly[2,2-bis(4-hydroxyphenyl)propane isophthalate. ] It will be clear that they perform well and are far better under the conditions used in the presence of organic solvents than similar amorphous thermoplastic polyesters such as . In addition, although the inherent viscosity is shown in each example in the text, the approximate molecular weight of the polymer calculated from this is shown below. Calculated molecular weights of polymers in examples

【table】

【table】 [Brief explanation of drawings]

FIG. 1 is a curve showing the exothermic crystallization peak.

Claims (1)

[Claims] 1. The melt viscosity measured by a capillary rheometer at a shear rate of 100 sec ^-1 is less than 10 ⁵ poise at 350°C, and the repeating unit is of the formula [In the formula, Y is at least one group selected from -CH ₂ CH ₂ -, [Formula] and -S -, and 90 mol% or more of Y is -CH ₂ CH ₂ -, and R is [ formula] [formula] and is at least one group selected from [Formula]. ] Linear polyester. 2. The linear polyester according to claim 1, wherein at least 67 mol% of R is [Formula] and 100 mol% of Y is -CH ₂ CH ₂ -. 3. The linear polyester according to claim 1, wherein at least 90 mol% of Y is -CH ₂ CH ₂ - and 100 mol% of R is [Formula]. 4 has a Tg of at least about 100°C and an inherent viscosity of at least about 0.3 as measured at 30°C at a concentration of 0.5 g polyester per 100 ml of a solution containing a solvent of 60 parts by weight phenol and 40 parts by weight sym-tetrachloroethane; , and the crystallization rate is about 0.2 min
2. The linear polyester according to item 1 above, wherein the polyester is larger than ^-1 . 5. The linear polyester according to item 4 above, having an inherent viscosity of at least about 0.5. 6. The linear polyester of item 5 above, wherein the crystallization rate is greater than about 0.5 min ^-1 . 7 100 mol% of Y is -CH ₂ CH ₂ - and 100 mol% of R
The linear polyester according to claim 1, wherein the mole % is [Formula]. 8 30 at a concentration of 0.5 g per 100 ml in a solvent containing phenol-sym-tetrachloroethane in a 60/40 weight ratio.
the inherent viscosity when measured at °C is at least about 0.3, and the rate of crystallization is about 0.2 min ^-1
8. The linear polyester according to item 7 above. 9. The linear polyester of item 8 above, having an inherent viscosity of at least about 0.5. 10. The linear polyester of item 9 above, wherein the crystallization rate is greater than about 0.5 min ^-1 .