KR20050016749A - Partially Ester-Exchanged SIPM and Process Therewith - Google Patents

Abstract

The present invention relates to a process for producing partially transesterified SIPM, such as alkali metal bis (2-hydroxyethyl) 5-sulfoisophthalate, from alkali metal dimethyl 5-sulfoisophthalate in alcohol. Partially transesterified SIPM in alcohols may be used to copolymerize with oligomers of terephthalic acid or dimethyl terephthalate and alcohols. The present invention also relates to a method of controlling the color of the dyeing polyester using a phosphorus compound.

Description

Partially Ester-Exchanged SIPM and Process Therewith

The present invention provides a process for preparing partially transesterified metal salts of dimethyl sulfoisophthalate in alcohols from metal salts of dimethyl sulfoisophthalate and repetitions derived from sulfoisophthalic acid, or salts or esters, carbonyl compounds and alcohols thereof. It relates to a method for producing a polymer comprising a unit.

Polyester is widely used in the manufacture of textile fibers and bottle resins, and can be produced by blending alcohols such as ethylene glycol and carbonyl compounds such as dimethyl terephthalate (DMT) or terephthalic acid (TPA). For example, DMT reacts with an alcohol such as ethylene glycol to form a bis-glycolate ester ("monomer") of terephthalate in a transesterifier column. These monomers are polymerized by condensation reaction in one or two prepolymerization reactors and then in the final polymerization reactor or finisher. TPA can be combined with ethylene glycol to form a slurry at 60 to 80 ° C. and then the slurry can be injected into the esterifier. Linear oligomers having a degree of polymerization of less than 10 are formed in one or two esterification groups (first and second two) at temperatures of 240 ° C. to 290 ° C. The oligomer is then polymerized in one or two prepolymerization reactors and then in a final polymerization reactor or finisher at a temperature of 250 ° C to 300 ° C.

Additives such as catalysts, stabilizers, quenchers and toners are typically added to the oligomers before esterification to the TPA slurry, in the esterifier or before the prepolymerization reactor. Commercial polyester processes typically use antimony compounds as polycondensation catalysts and phosphorus compounds as stabilizers. See, generally, Encyclopedia of Chemical Technology, 4th edition, John Wiley, New York, 1994, Volume 10, p662-685 and Volume 19, p609-653.

However, it is difficult to incorporate dye materials into or on the polyester. Thus, copolymers comprising repeating units derived from terephthalic acid, sulfoisophthalic acid and glycols are widely used, which can be used to render the fiber dyeable with a basic dye or to make the polyester hydrolyzable in water. Because. Such copolymers are referred to as cationic dyeing (CD) polyesters, in which a small amount of sulfonated isophthalate metal salt or ester thereof, for example sodium dimethylsulfoisophthalate (Na-SIPM) powder, is added to the transesterification of the DMT process It can manufacture by doing. Fibers made from CD copolymers give a clear tint when dyed with basic / cationic dyes and are dyed with a darker tint with disperse dyes.

U.S. Patent No. 5,559,205 discloses bis (2-hydroxyethyl) sodium 5-sulfoisophthalate (Na-SIPEG) or bis (fully esterified to the monomer line of the DMT process or the oligomer line of the TPA process or to the second esterification unit. A method for preparing cationic dyeable polyesters by adding 2-hydroxyethyl) lithium 5-sulfoisophthalate (Li-SIPEG) is disclosed.

US Pat. No. 6,075,115 discloses a process for preparing Na-SIPEG solution and Li-SIPEG solution from sodium 5-sulfoisophthalic acid (Na-SIPA) and lithium 5-sulfoisophthalic acid (Li-SIPA) powder. . To fully esterify Na-SIPA and Li-SIPA, comprising (1) a titanium compound, a dissolution accelerator, a phosphorus source and optionally a solvent, or (2) a titanium compound, a complexing agent, a phosphorus source and optionally a solvent of sulfonic acid, Special titanium catalyst is used. Fully esterified Na-SIPEG and Li-SIPEG solutions are prepared from the seller and shipped to the polyester manufacturer. The solution is then injected into the monomer line of the DMT process or into the oligomer line or the second esterifier of the TPA process or into the second or third vessel of the batch polymerization process to produce the copolyester.

Metal salts of 5-sulfoisophthalic acid fully esterified with methanol are also available. Sodium dimethyl 5-sulfoisophthalate (Na-SIPM), for example, is available from Wilmington, Delaware, USA. children. It may be purchased from DuPont Di Nemoir & Company (hereinafter referred to as “Dupont Corporation”).

It has been commercially practiced to produce Na-SIPEG solutions in glycol by completely transesterifying Na-SIPM with ethylene glycol. Manganese acetate catalyst was used as the transesterification catalyst. Sodium acetate can be added to reduce ether formation. The Na-SIPEG solution is then sent to the polyester manufacturer and added to the polyester process.

The process using fully esterified Na-SIPEG has several disadvantages, including the following. About 15-20% of Na-SIPEG forms dimers, trimers and other low molecular weight oligomers due to the long reaction time, resulting in non-uniform distributions within the polyester molecular chain, affecting spinning and texture performance. The Na-SIPEG solution should be diluted up to 20% for addition to the DMT monomer line or TPA oligomer line for acceptable spinning and texture performance. The 20% Na-SIPEG solution is expensive because separate equipment is needed to prepare the solution from Na-SIPM powder and glycol. The transport cost of the 20% solution is high. High investment costs are required for drying heated storage tanks, pumps and piping systems for 20% solutions. CD polyester manufacturers cannot control the properties of solutions such as DEG (diethylene glycol). Processes using fully esterified Li-SIPEG also have similar disadvantages.

Therefore, there is a need to develop a process for producing partially transesterified metal salts of dimethyl 5-sulfoisophthalate that are more stable at room temperature, especially at high concentrations. An advantage of using partially transesterified metal salts of dimethyl 5-sulfoisophthalate is that less dimers, trimers and other low molecular weight oligomers are produced, resulting in a more uniform basic dye point distribution in the polymers produced. Another advantage is that higher concentrations of Na-SIPEG, corresponding to 40% to 60%, can be injected into the DMT monomer line or the TPA oligomer line. Another advantage is that no manganese catalyst is required. Another advantage of the present invention is that it is possible to prepare partially transesterified metal salts of 5-sulfoisophthalate just prior to use in the preparation of polyesters, which can significantly reduce manufacturing and transportation costs.

It is also known that phosphoric acid is commonly used to inhibit discoloration of polyester homopolymers, but in some cases phosphoric acid does not improve the color of copolymers derived from terephthalic acid and sulfoisophthalic acid. Therefore, there is also a need to develop a method of improving the color of the dyeing polyester by using phosphorus compounds, in particular phosphorus compounds which are not acidic.

Summary of the Invention

Preparing a mixture by contacting a metal salt of dimethyl 5-sulfoisophthalate with glycol and heating the mixture under conditions sufficient to partially transesterify the methyl group in the metal salt of dimethyl 5-sulfoisophthalate, Disclosed is a process used to prepare partially transesterified metal salts of dimethyl 5-sulfoisophthalate, wherein the mixture comprises a catalyst as necessary.

Also disclosed is a process for the production of dyeing polyesters. The process optionally comprises a reaction mixture of (a) a carbonyl compound and a second glycol with a partially transesterified metal salt of dimethyl 5-sulfoisophthalate in the presence of a phosphorus compound and / or a catalyst or (b) a carbohydrate. Contacting oligomers derived from carbonyl and a second glycol.

As used herein, the acronym "SIPM" refers to (RO (O) C) ₂ ArS (O) ₂ OM ', wherein R is a methyl group or a mixture of methyl groups and hydrogen; M' is hydrogen, an alkali metal, an alkaline earth metal, Quaternary ammonium or phosphonium, or a combination of two or more thereof). Preferred M 'is an alkali metal such as lithium or sodium. Accordingly, SIPM may also include metal salts of 5-sulfoisoterephthalic acid partially or fully esterified with methanol, unless specifically indicated otherwise. Thus, "SIPM" can be any metal salt of dimethyl sulfoisophthalate unless specifically indicated otherwise. For example, Na-SIPM and Li-SIPM refer to sodium dimethyl sulfoisophthalate and lithium dimethyl sulfoisophthalate, respectively, because they are specifically indicated.

Thus, the term "metal salt of dimethyl sulfoisophthalate" or "SIPM" refers to a metal salt of sulfoisoterephthalic acid in which the protons of the COOH group have been partially or completely substituted with methyl groups to form COOCH ₃ . Examples of SIPMs include dimethyl 5-sulfoisophthalate; Alkali metal salts of dimethyl 5-sulfoisophthalate, such as sodium dimethyl 5-sulfoisophthalate, lithium dimethyl 5-sulfoisophthalate; Mono or diesters of dimethyl 5-sulfoisophthalic acid; Mono or diesters of alkali metal salts of dimethyl 5-sulfoisophthalate, but are not limited to these.

The term “partially transesterified metal salt of dimethyl sulfoisophthalate (hereinafter referred to as“ partially transesterified SIPM ”) may refer to about 50 to about 99%, preferably about 70 to about 95%, of methyl groups in SIPM, Most preferably, SIPM wherein 80 to 90% is substituted with lower alkyl groups other than methyl groups such as ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl or a combination of two or more thereof That is, "partially transesterified SIPM" refers to a lower alkyl group that is not about 50 to about 99%, preferably about 70 to about 95%, most preferably 80 to 90% methyl group as its ester group. It may include.

Any glycol capable of esterifying SIPM can be used as the glycol of the present invention. Preferred glycols may have from 2 to about 10, preferably 2 to about 8, most preferably 2 to 4 carbon atoms per molecule, for example alkylene glycols, polyalkylene glycols, polyoxyalkylenes Glycols or combinations thereof. Examples of suitable glycols include ethylene glycol, propylene glycol, isopropylene glycol, butylene glycol, 1-methyl propylene glycol, pentylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polyoxyethylene glycol, polyoxypropylene glycol, Polyoxybutylene glycol, and combinations of two or more thereof, but are not limited to these. Most preferred glycols in the present invention are alkylene glycols, such as ethylene glycol or 1,3-propanediol, since the polyesters prepared from them have a wide range of industrial uses.

Examples of partially transesterified SIPMs include combinations of lithium dimethyl 5-sulfoisophthalate, lithium bis (2-hydroxyethyl) 5-sulfoisophthalate; A combination of sodium dimethyl 5-sulfoisophthalate, sodium bis (2-hydroxyethyl) 5-sulfoisophthalate; A combination of sodium dimethyl 5-sulfoisophthalate, sodium bis (3-hydroxypropyl) 5-sulfoisophthalate; A combination of lithium dimethyl 5-sulfoisophthalate, lithium bis (2-hydroxyethyl) 5-sulfoisophthalate, sodium bis (2-hydroxyethyl) 5-sulfoisophthalate; Of lithium dimethyl 5-sulfoisophthalate, lithium bis (2-hydroxyethyl) 5-sulfoisophthalate, sodium dimethyl 5-sulfoisophthalate, sodium bis (2-hydroxyethyl) 5-sulfoisophthalate Combinations; And combinations of two or more thereof, but is not limited thereto.

The metal SIPM can be combined with the glycol in any suitable container, vessel or reactor in any suitable manner to produce the metal SIPM-glycol mixture. The amount of metal SIPM can be any amount so long as it is capable of producing the desired partially transesterified metal SIPM. Generally, based on the total weight of the metal SIPM-glycol mixture, the metal SIPM is present in the range of about 5 to about 70 weight percent, preferably about 10 to about 50 weight percent, most preferably 20 to 30 weight percent. Can be. This amount may be expressed as an amount capable of producing the desired partially transesterified SIPM described above.

A catalytic amount of catalyst, for example a metal salt such as sodium acetate anhydride or sodium acetate trihydrate or lithium acetate or lithium acetate dihydrate, is about 0.2 to about 200 g, preferably 2 to 20 g, per kg of SIPM in the SIPM glycol mixture (Or at a molar ratio of catalyst to SIPM of from about 0.002: 1 to about 0.15: 1, preferably from 0.01: 1 to 0.1: 1) to promote transesterification and control the formation of diethylene glycol and 50 to about 99%, preferably about 70 to about 95%, most preferably 80 to 90% of removal or exchange of the desired methyl group is achieved. No manganese catalyst is needed.

Generally, the metal SIPM-glycol mixture in the form of a slurry is at least about 5 minutes, preferably at least about 1, at about 60 ° C to about 250 ° C, preferably at about 100 ° C to about 200 ° C, most preferably at 140 ° C to 190 ° C. The solution of partially esterified SIPM can be prepared by heating for from about 10 hours. Such exchange also produces a vapor of methanol, which, together with any glycol, can be condensed in the condenser, discharged into the air, or flow into a water separation column. The resulting solution can then be further heated to the same or lower temperature. Further heated or unheated solutions can be injected, for example, into the monomer line or the prepolymerization reactor of the DMT process, into the oligomer line or the second esterifier or the prepolymerization reactor of the TPA process, or of the batch polymerization process discussed in the background. It can be injected into a second or third container and used directly in the manufacturing process of the polyester.

Optionally, an antifoaming agent such as polydimethylsiloxane (or an emulsion or solution thereof) is added to the slurry of the metal SIPM-glycol mixture (before, during or after the slurry is heated) or solution (while the solution is formed or continuously heated or cooled). Can be introduced in Defoamers can reduce the surface tension to prevent foaming of the slurry or solution, and to stabilize subsequent polycondensation processes when the solution is used in the preparation of the polyester. Since the antifoaming agent is known to those skilled in the art, the description is omitted here for brevity.

According to another embodiment of the present invention, the process of the present invention optionally comprises (a) contacting partially transesterified SIPM in the presence of a phosphorus compound and / or a catalyst with a polymerization mixture comprising a carbonyl compound and a second glycol Or (b) contacting partially transesterified SIPM with an oligomer derived from a carbonyl compound and a second glycol.

The catalyst and partially esterified SIPM may be the same as those disclosed above, the contents of which are included herein. The second glycol may be the same or different than the glycol disclosed above. Preferred second glycols in the present invention are ethylene glycol, 1,3-propanediol or combinations thereof.

When used with a polyester catalyst, any phosphorus compound can be used which produces a polyester having a lower yellowness compared to the polyester produced from the catalyst in the absence of a phosphorus compound. Examples of suitable phosphorus compounds include polyphosphoric acid or salts thereof, phosphonate esters, pyrophosphoric acid or salts thereof, pyrophosphoric acid or salts thereof, phosphoric acid or salts thereof, phosphorous acid or salts thereof, and combinations of two or more thereof. Although it may be mentioned, it is not limited to these. The polyphosphoric acid may be represented by the formula H _{n + 2} P _n O _{3n + 1} , wherein n is 2 or more. The phosphonate esters may be of the formula (R ² O) ₂ P (O) ZCO ₂ R ² , wherein each R ² may be the same or different and may independently be H, C _1-4 alkyl, or a combination thereof And Z can be C _1-5 alkylene, C _1-5 alkylidene or combinations thereof, di (polyoxyethylene) hydroxymethyl phosphonate and combinations of two or more thereof). have. The salt may be an alkali metal salt, alkaline earth metal salt, ammonium salt or a combination of two or more thereof.

Examples of suitable phosphorus compounds include potassium tripolyphosphate, sodium tripolyphosphate, potassium tetra phosphate, sodium pentapolyphosphate, sodium hexapolyphosphate, potassium pyrophosphate, potassium pyrophosphate, sodium pyrophosphate, sodium pyrophosphate decahydrate , Sodium pyrophosphite, ethyl phosphonate, propyl phosphonate, hydroxymethyl phosphonate, di (polyoxyethylene) hydroxymethyl phosphonate, methylphosphonoacetate, ethyl methylphosphonoacetate, methyl ethyl Phosphonoacetate, ethyl ethylphosphonoacetate, propyl dimethylphosphonoacetate, methyl diethylphosphonoacetate, triethyl phosphonoacetate, phosphoric acid or salts, phosphorous acid or salts, or combinations of two or more thereof. It is not limited.

The phosphorus compound may be present in the process before, during or after the carbonyl compound or ester thereof is esterified or transesterified. Similarly, it may be present before, during or after the polycondensation step. Phosphorus compounds are prepared using titanium containing catalysts or other catalysts or trace elements by inhibiting the catalytic activity of titanium containing catalysts or other catalysts or trace elements such as manganese, cobalt, zinc, aluminum, iron, lead or silicon It can be used to reduce the discoloration of one polyester. The phosphorus compound may be mixed with a catalyst such as titanium, antimony, manganese, zinc before the catalyst is introduced into the polyester reaction process. Alternatively, the phosphorus compound may be introduced into the process separately before or after the catalyst is introduced.

Any carbonyl compound that can produce a polyester when combined with an alcohol can be used. Such carbonyl compounds include, but are not limited to, acids, esters, amides, acid anhydrides, acid halides, salts of carboxylic acid oligomers or polymers having repeating units derived from acids, or combinations of two or more thereof. It is not limited. Preferred acids in the present invention are organic acids such as carboxylic acids, or salts thereof. Oligomers of carbonyl compounds, such as TPA and glycols, generally have a total of about 2 to about 100, preferably about 2 to about 20, repeat units derived from carbonyl compounds and glycols.

Examples of suitable organic acids include, but are not limited to, terephthalic acid, isophthalic acid, naphthalic acid, succinic acid, adipic acid, phthalic acid, glutaric acid, oxalic acid, maleic acid and combinations of two or more thereof. Examples of suitable esters include, but are not limited to, dimethyl adipate, dimethyl phthalate, dimethyl terephthalate, dimethyl glutarate and combinations of two or more thereof. Preferred organic dibasic acids in the present invention are terephthalic acid or its ester dimethyl terephthalate, since the dyeing polyesters prepared therefrom have a wide range of industrial uses.

Contacting the carbonyl compound with the second glycol in the presence of a catalyst can be carried out by any suitable means.

Any suitable conditions for carrying out the preparation of the polyester are in the range of about 0.001 to about 500 ° C, preferably in the range of about 200 ° C to about 400 ° C, most preferably 250 ° C to 300 ° C Conditions for about 0.2 to about 20 hours, preferably about 0.3 to about 15 hours, most preferably 0.5 to 10 hours, under a pressure in the range of about 1 atmosphere.

The molar ratio of second glycol to carbonyl compound can be any ratio as long as it is a ratio capable of carrying out the preparation of esters or polyesters. Generally, the ratio may range from about 1: 1 to about 10: 1, preferably from about 1: 1 to about 5: 1, most preferably from 1: 1 to 4: 1. The CD polyester prepared by the process of the present invention may comprise about 1 to about 200 ppm titanium and about 1 to about 200 ppm, preferably about 5 to about 100 ppm phosphorus. When using two or more carbonyl compounds, the molar ratio of the second or third carbonyl compound to the first carbonyl compound may each range from about 0.0001: 1 to about 1: 1. For example, the dyeing polyester may be a repeat unit derived from 85 mol% to 99.9 mol% of terephthalic acid or terephthalate, and 0.1 mol% to 15 mol% of sodium 5-sulfoisophthalic acid or lithium 5-sulfoisophthalic acid. And repeat monomers derived from.

The catalyst can be a titanium, cobalt, antimony, manganese or zinc catalyst commonly used in the preparation of polyesters. Preferred antimony compounds can be any antimony compound that can be substantially dissolved in the solvents disclosed above. Examples of suitable antimony compounds include antimony oxide, antimony acetate, antimony hydroxide, antimony halide, antimony sulfide, antimony carboxylate, antimony ether, antimony glycolate, antimony nitrate, antimony sulfate, antimony phosphate and combinations of two or more thereof Although it may be mentioned, It is not limited to these. Catalysts represented by elements of Co, Sb, Mn, Zn or Ti, Al, Si are from about 0.001 to about 30,000 ppm, preferably from about 0.1 to about 1,000 ppm, most preferably in a medium comprising a carbonyl compound and glycol May be present in the range of 1 to 100 ppm. If present, cobalt may be in the range of about 0.01 to about 1,000 ppm of the reaction medium. The description of the catalyst is omitted herein because such a catalyst is known to those skilled in the art.

Titanium containing catalysts may be prepared by any means known to those skilled in the art, such as those disclosed in US Pat. Nos. 6,066,714 and 6,166,170 discussed above, and for brevity, description thereof is omitted herein. Examples of commercially available organic titanium compounds include TYZOR® TPT and TYZOR® TBT (tetra isopropyl titanate and tetra n-butyl titanate, respectively), but are not limited to these. no.

The process of the invention can also be carried out using any conventional melt or solid state technique in the presence or absence of toner compounds to reduce the color of the polyesters produced. Examples of toner compounds include cobalt aluminate, cobalt acetate, carbazole violet (Hoechst-Celanese, Coventry, Rhode Island, USA or Sun Chemical Corp., Cincinnati, Ohio, USA). Estofil Blue S-RLS (registered trademark) and Solvent Blue 45 (trade name) (manufactured by Sandoz Chemicals, Charlotte, NC), CuPc Blue (cincinnati, Ohio) Chemical company), but is not limited to these. These toner compounds are known to those skilled in the art, and description thereof will be omitted herein. The toner compound may be used with the catalyst disclosed herein in an amount of about 0.1 ppm to 1,000 ppm, preferably about 1 ppm to about 100 ppm, based on the weight of the polyester produced.

The process according to the invention can also be carried out using any conventional melting or solid state technique in the presence or absence of a photobleaching compound to reduce the yellowness of the polyesters produced. Examples of photobleaching compounds include 7-naphthotriazinyl-3-phenylcoumarin (trade name "Leucopure EGM" from Sandoz Chemicals, Charlotte, NC), 4,4'-bis (2-benzoxazolyl) Stilbenes (trade name "Eastobrite" from Eastman Chemical, Kingsport, Tenn.) Are, but are not limited to these. The photobleach compounds are known to those skilled in the art, and description thereof will be omitted herein. Photobleach compounds may be used with the catalysts disclosed herein in amounts of about 0.1 ppm to 10,000 ppm, preferably about 1 ppm to about 1,000 ppm, based on the weight of the polyesters produced.

The following examples are intended to illustrate the invention in more detail and should not be construed as excessively limiting the scope of the invention.

Unconverted methyl ester in solution was analyzed by gas chromatography (GC). Reflux with 2-aminoethanol (2AE) to free methanol from the methyl ester in the sample. 2AE contained ethanol as internal standard. The heated mixture was diluted with 1-butanol and cooled to inject samples from the liquid layer into GC. The ratio of methanol area (from unconverted methyl ester) and ethanol area was corrected for sample weight and reaction index to convert to unconverted methyl ester weight percent.

Diethylene glycol (DEG) in partially transesterified SIPM solution was analyzed in the same manner as DEG in polymers, which required depolymerization. Samples were treated with 2-aminoethanol (2AE) containing benzyl alcohol (BA) as internal standard. The reaction mixture was diluted with isopropyl alcohol and injected by gas chromatography. The area ratios of the DEG and BA peaks were corrected for sample weight and converted to DEG weight percent as assay factor.

The molecular weight of the polymer was measured by intrinsic viscosity (IV). IV is expressed as LRV (Laboratory Relative Viscosity). LRV is the ratio of the viscosity of a solution of 0.8 g of polymer dissolved in 10 ml of hexafluoroisopropanol (HFIP) containing 100 ppm sulfuric acid at room temperature to the viscosity of sulfuric acid itself containing HFIP, each of which is 25 in a capillary viscometer. It is measured at ℃. The use of HFIP as a solvent is important because it enables dissolution at a predetermined temperature and thus prevents polymer degradation generally occurring when the polyester is dissolved at elevated temperatures.

Example 1

This example illustrates the preparation of a partially transesterified Na-SIPM solution.

Ethylene glycol (EG; 800 g), dimethyl sodium 5-sulfoisophthalate (Na-SIPM; 400 g; manufactured by Dupont) and sodium acetate anhydride (NaAc; 8.0 g; Jarchem Industries, Newark, NJ, USA Industries) was added to a 1,500 ml flask to prepare a slurry. The total weight of the mixture was 1208 g. The flask was covered with a small holed aluminum foil to allow methanol vapors to flow. The slurry in the flask was stirred with a magnetic stirrer on a heating plate.

 It took 32 minutes to heat the stirred slurry from 27 ° C to 141 ° C. When the temperature reached 141 ° C., the Na-SIPM powder completely dissolved. It began to boil at about 141 ° C. After 96 minutes, the solution temperature was slowly raised from 141 ° C. to 159 ° C. with an average of 148 ° C. during this period. Due to the evaporation of methanol the solution weight decreased from 1,208 g to 1,136 g. Subsequently, 64 g of ethylene glycol was added to make the total solution 1,200 g. The solution was clear after cooling and did not form a solid or gel. GC analysis showed that 79% of the methanol groups were converted and evaporated. The material resin showed 72 g evaporated, of which 69 g was methanol and 3 g was ethylene glycol. As a result of laboratory analysis, DEG (diethylene glycol) was 0.021% in solution.

Example 2

This example illustrates the polymerization of a copolymer containing 2 mol% partially transesterified Na-SIPM solution from a DMT monomer in an autoclave.

400 ml of catalyst, DMT (dimethyl terephthalate; manufactured by Dupont; 18.1 kg) and 12.5 kg of ethylene glycol in a solution of ethylene glycol containing 8.2 g manganese acetate tetrahydrate and 5.4 g antimony oxide Sb ₂ O ₃ Charged in a strong still. The top temperature of the condensation column was adjusted to 85 ° C. 6,060 g of methanol and 2,700 g of ethylene glycol were then removed from the distiller. After 205 minutes in the still, the monomer temperature rose to 240 ° C. The monomer was then added dropwise into a stainless steel clave. Immediately after dropping the monomer into the clave, 80 ml of phosphorus solution (prepared by mixing 104 ml of 85% H ₃ PO ₄ and 2,000 ml of ethylene glycol) was added to the clave. Then 1660 g of partially transesterified Na-SIPM solution prepared in Example 1 were added to the clave. Vacuum was slowly applied to 1 mmHg from atmospheric pressure over 60 minutes and then maintained at 1 mmHg. The clave temperature was maintained at 275 ° C. The polymerization reaction was stopped when the torque of the stirrer reached 30 psi (207 kPa) at 6 rpm. The total time in the clave was 145 minutes. The polymer was quenched and cut into flakes. Laboratory analysis showed an inherent viscosity of 0.479 (LRV 12.65) and a DEG of 1.297%.

Example 3

This example illustrates the polymerization of a copolymer containing 2 mol% partially transesterified Na-SIPM from a TPA oligomer in a kettle.

TPA (terephthalic acid; manufactured by DuPont) slurry tank was continuously charged with TPA at 44 to 57 kg / hour. The speed was adjusted with a powder screw feed to maintain the desired polymer flow rate of 54 kg / hour. TPA slurries were prepared by filling ethylene glycol at a rate such that the molar ratio of ethylene glycol to TPA was 2.2: 1 by mass flow meter. The temperature in the slurry tank was about 80 ° C. The TPA slurry was injected into the recycle esterifier at the desired polymer flow rate and at a rate to maintain a constant oligomeric liquid level in the esterifier. The temperature in the esterifier was maintained at 282 to 284 ° C. After condensing the vapor from the esterifier and separating into ethylene glycol and water, ethylene glycol was mixed with fresh ethylene glycol and charged into the TPA slurry. The oligomer from the esterification group contained no catalyst and had a degree of polymerization of 5 to 10.

The pot was preheated to 265 ° C. The 500 ml resin kettle was provided with a Zipy Mixer stirrer, thermocouple, condenser and nitrogen sweep. In this kettle 83 g of ethylene glycol, 400 g of the terephthalic acid oligomer prepared above, 36.36 g of partially transesterified Na-SIPM solution prepared in Example 1, a 20% slurry of 6 g of TiO ₂ in ethylene glycol and 8 g of antimony glycolate solution (containing 1 wt.% Sb) was added. The temperature was increased to 265 ° C. and maintained at that temperature until the oligomer liquefied and then the stirrer was operated at 60 rpm. The temperature was raised to 275 ° C. and the vacuum was reduced to 120 mm Hg and held for 20 minutes. The temperature was raised to 280 ° C. and the vacuum was reduced to 30 mm Hg and held for 20 minutes. The vacuum was then reduced to 1 mm Hg while maintaining the temperature at 280 ° C. When the torque reached 4 pounds (8.8 kg), the stirrer speed was reduced to 40 rpm. The polymerization was stopped when the torque reached 4.5 pounds (10 kg). The polymer melt was poured into a water bath to solidify the melt and the resulting solid was crystallized at 90 ° C. for 1 hour in a vacuum oven and ground to pass through a 2 mm filter. The ground polymer was dried again at 90 ° C. for 1 hour in an oven. The polymer had a good color. Laboratory Assay: Inherent Viscosity 0.571 (LRV 16.11), DEG 1.633%.

Claims (8)

Contacting the metal SIPM with alkylene glycol to prepare a mixture, and heating the mixture to produce a partially transesterified SIPM solution, preferably 50 to 99%, more preferably, of the methyl groups in the metal SIPM Preferably 80 to 95% is substituted with an alkyl group derived from said glycol. The method of claim 1, wherein the partially transesterified SIPM solution comprises a combination of lithium dimethyl 5-sulfoisophthalate, lithium bis (2-hydroxyethyl) 5-sulfoisophthalate; A combination of sodium dimethyl 5-sulfoisophthalate, sodium bis (2-hydroxyethyl) 5-sulfoisophthalate; A combination of sodium dimethyl 5-sulfoisophthalate, sodium bis (3-hydroxypropyl) 5-sulfoisophthalate; A combination of lithium dimethyl 5-sulfoisophthalate, lithium bis (2-hydroxyethyl) 5-sulfoisophthalate, sodium bis (2-hydroxyethyl) 5-sulfoisophthalate; Of lithium dimethyl 5-sulfoisophthalate, lithium bis (2-hydroxyethyl) 5-sulfoisophthalate, sodium dimethyl 5-sulfoisophthalate, sodium bis (2-hydroxyethyl) 5-sulfoisophthalate Combinations; Or a combination of two or more thereof. The process according to claim 1 or 2, which is carried out in the presence of a catalytic amount of a catalyst, preferably a metal acetate, more preferably lithium acetate, sodium acetate or a combination thereof. A partially transesterified SIPM solution in a first glycol is prepared by (1) a mixture comprising a carbonyl compound and a second glycol, or (2) 2 to about 100 repeating units derived from the carbonyl compound and the second glycol. Contacting the oligomer having a polymer with a repeating unit derived from the SIPM, the first glycol, the second glycol, and the carbonyl compound under conditions effective to prepare the partially transesterified SIPM solution. The method as defined in any one of claims 1 to 4, wherein each of the first glycol and the second glycol is an alkylene glycol, a polyalkylene glycol, a polyoxyalkylene glycol and a combination of two or more thereof. . The method according to claim 4, wherein the first glycol and the second glycol are each independently ethylene glycol, propylene glycol, isopropylene glycol, butylene glycol, 1-methyl propylene glycol, pentylene glycol, diethylene glycol, triethylene glycol, Polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol, and combinations of two or more thereof, preferably ethylene glycol or 1,3-propanediol. The phosphoric acid or salt thereof, phosphorous acid or salt thereof, polyphosphoric acid or salt thereof, phosphonate ester, pyrophosphoric acid or salt thereof, pyrophosphoric acid or salt thereof, two or more thereof Wherein the phosphorus compound is introduced together with or separately from the catalyst composition. The method of claim 6, wherein the phosphorus compound is phosphoric acid, sodium phosphate, potassium phosphate, phosphorous acid, potassium tripolyphosphate, sodium tripolyphosphate, potassium tetrapolyphosphate, sodium pentapolyphosphate, sodium hexapolyphosphate, potassium pyrophosphate, potassium pi Rhophosphite, sodium pyrophosphate, sodium pyrophosphite, ethyl phosphonate, propyl phosphonate, hydroxymethyl phosphonate, di (polyoxyethylene) hydroxymethyl phosphonate, methylphosphonoacetate, Ethyl methylphosphonoacetate, methyl ethylphosphonoacetate, ethyl ethylphosphonoacetate, propyl dimethylphosphonoacetate, methyl diethylphosphonoacetate, triethyl phosphonoacetate, and combinations of two or more thereof, preferably Potassium Tripolyphosphate, Potassium Pie Rophosphate, di (polyoxyethylene) hydroxymethyl phosphonate or triethyl phosphonoacetate. The method of claim 4, wherein the carbonyl compound is terephthalic acid, dimethyl terephthalate or a combination thereof.