Abstract: The invention relates to an improved linear microdialysis probe comprising a continuous length of flexible tubing (1) having at least one window (4) formed therein, said window covering at least one part of the circumference of the tubing, while the remaining part forms at least one unbroken connection between a first end of said tubing and a second end of said tubing, said ends adapted to be attached to an inlet for perfusion liquid and the other end forming an outlet for the dialysate, said at least one window (4) exposing a tubular semipermeable membrane (2).

Abstract: The invention relates to a process for making a thermoplastic polyester, which comprises contacting at least one carboxylic acid-based compound and at least one alcohol-based compound in esterification and subsequent polycondensation reactions, in the presence of certain exfoliated inorganic nano-layered titanates acting as a catalyst.

Abstract: Polyester compositions, especially polyethylene terephthalate homopolymer and copolymers, are disclosed containing titanium catalysts and catalyst deactivator added late in the manufacturing processing having reduced acetaldehyde generation rates. The polyester compositions are low in free acetaldehyde, making them suitable for fabrication into beverage containers for relatively tasteless beverages such as bottle water. Furthermore, the polyesters are polymerized to a high inherent viscosity in reduced processing time, without the necessity of further polymerization in the solid state, and in the absence of acetaldehyde scavengers leading to polyester polymers having reduced color.

Abstract: Disclosed are formaldehyde-free, thermally-curable, alkaline, aqueous binder compositions, curable to formaldehyde-free, water-insoluble thermoset polyester resins, and uses thereof as binders for non-woven fibers and fiber materials.

Abstract: The present invention is aimed to provide a method for producing a polyester with reduced CD content and elution amount, in which even after the production method, a reduction in physical properties of the polyester is small, and furthermore, a polyester having good moldability can be produced, and the present invention is concerned with a method for producing a polyester including an esterification reaction step of allowing an aliphatic diol and an aliphatic dicarboxylic acid to react with each other; a step of pelletizing a polyester obtained through the esterification reaction step; and a contact treatment step of bringing the obtained polyester pellets into contact with a mixed solution containing ethanol and water, wherein the mixed solution contains water in an amount of 10% by mass or more and not more than 99% by mass relative to the whole of the mixed solution.

Abstract: The invention provides a polycondensation catalyst for producing polyester by an esterification reaction or a transesterification reaction between a dicarboxylic acid or an ester-forming derivative thereof and a glycol, wherein the polycondensation catalyst comprises particles of a solid base having on the surfaces an inner coating layer of titanic acid in an amount of from 0.1 to 50 parts by weight in terms of TiO2 per 100 parts by weight of the solid base, and an outer coating layer either of an oxide of at least one element selected from aluminum, zirconium and silicon, or of a composite oxide of at least two elements selected from aluminum, zirconium and silicon on the surface of the inner coating layer in an amount of from 1 to 50 parts by weight per 100 parts by weight of the solid base.

Abstract: The present invention relates to aliphatic or aliphatic-aromatic polyesters and copolyesters comprised of biobased ?-hydroxyfatty acids or derivatives thereof, processes for the preparation thereof, and compositions thereof having improved properties. The copolyesters of the present invention may also contain additional components that can be selected from aliphatic or aromatic diacids, diols and hydroxyacids obtained from synthetic and natural sources. The biobased ?-hydroxyfatty acids that comprise the polyesters and copolyesters of the present invention are made using a fermentation process from pure fatty acids, fatty acid mixtures, pure fatty acid ester, mixtures of fatty acid esters, and triglycerides from various sources. The polyesters of the present invention may contain various amounts and types of ?-carboxyfatty acids depending on the engineered yeast strain used for the bioconversion as well as the feedstock(s) used.

Abstract: Provided is a composition for manufacturing a polyester resin having a molar ratio of a diol compound to a dicarboxylic acid compound ranging from 1.05 to 1.4, in which the composition includes 5 ppm to 50 ppm of a phosphorous (P) compound (based on an amount of P), 10 ppm to 40 ppm of a cobalt (Co) compound (based on an amount of Co), 0.2 ppm to 20 ppm of a color enhancer, and 5 ppm to 25 ppm/3 ppm to 30 ppm of a titanium (Ti)-germanium (Ge) composite catalyst compound (based on an amount of Ti/Ge), based on weight percentage.

Abstract: A manufacturing method of polyethylene terephthalate including a step of melt polycondensation in presence of polycondensation catalyst represented by general Formula (I), wherein R1 represents an alkyl group having from 2 to 12 carbon atoms, and melt polycondensed polyethylene terephthalate has an intrinsic viscosity of from 0.48 to 0.53 dL/g and a terminal carboxyl number of from 14 to 22 mmol/kg; and a step of solid phase polycondensation to obtain solid phase polycondensed polyethylene terephthalate having an intrinsic viscosity of from 0.70 to 0.86 dL/g, and a terminal carboxyl number of less than 15 mmol/kg, followed by a step of applying an aqueous solution of at least one salt selected from the group consisting of acetate, carbonate, and sulfate of sodium, potassium, or cesium to the solid phase polycondensed polyethylene terephthalate, and then drying the polyethylene terephthalate, wherein the final content of sodium, potassium or cesium atom in dried polyethylene terephthalate is from 2 to 25 ppm.

Abstract: The present invention seeks to provide a resin composition which contains an aromatic polycarbonate resin and a polyester resin and which has excellent mechanical strength, flowability and thermal stability and also has excellent moist heat resistance together. The present invention is a resin composition containing 50 to 99 parts by weight of an aromatic polycarbonate resin (component A) and 1 to 50 parts by weight of a polyester resin (component B), the component B being a polyester resin polymerized in the presence of a titanium-phosphorus catalyst obtained by reacting titanium tetrabutoxide, etc., with monolauryl phosphate, etc.

Abstract: An antimony-free PET resin produced by using an inorganic Ti—Mg catalyst and a small amount of blue and red dyes, in the absence of an antimony catalyst or a phosphorus stabilizer; and, in a melt spinning process for producing PET polyester fiber, the PET resin demonstrates excellent spinnability but no yarn breaks or aggregation of TiO2 delustering agent so that the resultant PET polyester fiber features commercially desired in both color tone and glossiness. Especially the PET resin and the PET polyester fiber containing no antimony are therefore environmentally friendly by causing no heavy metal pollution to the environment.

Abstract: A process of preparing a polyalkylene terephthalate comprising reacting an alkylene diol and an aromatic dicarboxy compound that is an aromatic dicarboxylic acid, aromatic dicarboxylic (C1-C3)alkyl ester, or a combination thereof, wherein ester interchange and polymerization occurs in the presence of a catalyst complex formed by the reaction of tetraisopropyl titanate and a boron, phosphorous or nitrogen-containing complexing agent, which catalyst can be synthesized in situ prior to ester interchange and introduced to a mixture of the alkylene diol and the aromatic dicarboxy compound prior to ester interchange.

Abstract: A polycondensation reaction mixture is disclosed which includes a catalyst, acyclic esters, ethylene glycol, and water. The catalyst is a titanium atrane. The polycondensation reaction mixture is prepared by the steps of (a) contacting a solution comprising a titanium (IV) alkoxide compound and a first solvent with an organic acid; (b) contacting the solution formed in step (a) with a substituted or unsubstituted trialkanolamine to form an impure catalyst; (c) purifying the impure catalyst to form the titanium atrane catalyst; and (d) bringing the catalyst into contact with the acyclic esters under conditions that produce the ethylene glycol and water.

Abstract: The present invention provides a method of producing a polymer, which comprises the step of performing a polymerization reaction using, as a starting material, an organic acid obtained by allowing a microorganism or a treated cell thereof to act on an organic raw material, wherein said microorganism has an ability to produce an organic acid and has been modified so as to produce less aromatic carboxylic acid as compared to an unmodified strain.

Abstract: The invention relates to a process for the preparation of titanium glycolate comprising the steps of reacting a titanium alkoxide with ethylene glycol in a molar ratio of the titanium alkoxide to ethylene glycol from 1:2 to 1:4 in a protic solvent at a temperature in the range from 50 to 100° C. to form titanium glycolate. The invention also relates to the titanium glycolate obtainable by said process and to use of said titanium glycolate in a catalyst composition in the preparation of a polyester or in a transesterification process.

Abstract: A manufacturing method of polyethylene terephthalate including a step of melt polycondensation in presence of polycondensation catalyst represented by general Formula (I), wherein R1 represents an alkyl group having from 2 to 12 carbon atoms, and melt polycondensed polyethylene terephthalate has an intrinsic viscosity of from 0.48 to 0.53 dL/g and a terminal carboxyl number of from 14 to 22 mmol/kg; and a step of solid phase polycondensation to obtain solid phase polycondensed polyethylene terephthalate having an intrinsic viscosity of from 0.70 to 0.86 dL/g, and a terminal carboxyl number of less than 15 mmol/kg, followed by a step of applying an aqueous solution of at least one salt selected from the group consisting of acetate, carbonate, and sulfate of sodium, potassium, or cesium to the solid phase polycondensed polyethylene terephthalate, and then drying the polyethylene terephthalate, wherein the final content of sodium, potassium or cesium atom in dried polyethylene terephthalate is from 2 to 25 ppm.

Abstract: Disclosed are formaldehyde-free, thermally-curable, alkaline, aqueous binder compositions. The disclosed binder compositions may be cured to substantially water-insoluble thermoset polyester resins, including formaldehyde-free, substantially water-insoluble thermoset polyester resins. Uses of the disclosed binder compositions as binders for non-woven fibers and fiber materials are also disclosed.

Abstract: This invention is reporting new N-heterocyclic carbene based zirconium (or hafnium) complexes and their uses as catalysts for the lactones ring opening polymerization. These new catalysts are robust and versatile and exert control over polymer molecular weight and/or stereochemistry and exhibit high reactivity (cf. for low temperature applications). In particular the new catalysts show both enhanced activity and at the same time a better selectivity than the catalysts employed by the prior art.

Abstract: The present invention concerns a method for producing an aqueous dispersion (X1), the method including a step that includes mixing an aqueous dispersion liquid (W) of resin particles (A) comprising a resin (a) with a precursor (b0) of a resin (b) or an oily liquid (OL) comprising the precursor (b0) and an organic solvent to disperse the precursor (b0) or the oily liquid (OL) in the aqueous dispersion liquid (W), followed by causing the precursor (b0) to react in the aqueous dispersion liquid (W) to form resin particles (B) comprising the resin (b), thereby obtaining the aqueous dispersion (X1) of resin particles (C) having a structure where resin particles (A) are adhered on the surface of the resin particles (B), wherein at least one of the resin (a) and the resin (b) contains a polyester resin (p1) formed in the presence of a specific titanium catalyst (t) or a resin (p2) having the polyester resin (p1) as a constituent unit.

Abstract: A polymer additive for improving the reheat characteristics of a polymer or polymeric composition comprises an inorganic material which is such that a 2.5 mm thick polyethylene terephthalate plaque incorporating the inorganic material has, when tested, an absorption ratio of less than 0.9, wherein the absorption ratio is either the ratio of A1/A2 or the ratio A1/A3, wherein: A1 is the maximum absorption between 400 nm and 550 nm; A2 is the maximum absorption between 700 to 1100 nm; A3 is the maximum absorption between 700 to 1600 nm. Preferred inorganic materials are titanium nitride, indium tin oxide and lanthanum hexaboride.

Abstract: The present invention relates to a process for producing PET based on titanium catalyst having acceptable properties for resin used in the production of bottles for beverages. More particularly the invention relates to a process in which the incoming pre-polymer temperature is higher than the final outlet temperature in the final melt phase polycondensation reactor.

Abstract: A process for removing metal species from a composition comprising contacting: a. an oligomer mixture stream comprising the monomers of a partially aromatic polyester polymer and at least one metal species, or b. a molten polyester polymer stream comprising partially aromatic polyester polymers and at least one metal species, with a non-catalytic porous material in the presence of hydrogen to produce a treated stream containing a reduced amount of at least one metal species. There are provided compositions comprising a partially aromatic polyester polymer having an It.V. of at least 0.50 produced in a direct esterification melt phase process, from greater than 0 to less than 50 ppm antimony, and less than 40 ppm cobalt, or produced in an ester exchange melt phase process, having from greater than zero to less than 5 ppm titanium and less than 10 ppm manganese.

Abstract: The invention provides: a polycondensation catalyst for polyester production, which contains titanium atoms, alkaline earth metal atoms and phosphorus atoms, has high reactivity and excellent long-term storage stability, can be easily produced industrially, and has an advantage in cost; a polyester resin obtained with the catalyst; and a molded article. These are: a polymerization catalyst for polyester production containing titanium atoms, alkaline earth metal atoms and phosphorus atoms and having a specific constitution; a polyester resin obtained with the catalyst; and a molded article.

Abstract: Method for producing polyesters using titanium atrane catalysts is disclosed. Also disclosed are methods for making the titanium atrane catalysts. The titanium atrane catalysts are useful as esterification and/or polycondensation catalysts, have similar activity, color and byproduct formation as conventional catalyst systems, but with reduced toxicity and regulatory concerns.

Abstract: Disclosed are phosphinic acid compounds of formula I, II or III where R1 and R1? are for instance straight or branched C1-C50alkyl, R2 is for instance straight or branched C22-C50alkyl, R3 and R3? are for instance straight or branched C1-C50alkyl, R4 is for instance straight or branched C1-C50alkylene and m is from 2 t 100. Also disclosed are polyester compositions comprising the compounds of formula I, II and III.

Abstract: A poly(lactic acid) resin composition is provided, comprising (a) a poly(lactic acid) resin, (b) at least one modifier selected from at least one metal/nonmetal alkoxide, at least one metal/nonmetal alkoxide having at least one functional group capable of reacting with the poly(lactic acid) resin, or a mixture thereof, (c) a first catalyst, and (d) optionally, a second catalyst. A process for preparing a transparent and impact-resistant article from the poly(lactic acid) resin composition of the invention, and articles prepared therefrom are also provided.

Abstract: Biodegradable compositions containing an aliphatic-aromatic copolyester derived from aromatic polyesters. Methods of making the compositions through an in situ phosphorus containing titanium based catalyst and articles made from the compositions.

Abstract: The invention provides a method of making a polymer in the presence of a catalyst composition having an empirical formula M(glycerol)a(X)b, where M represents a metal atom selected from titanium, zirconium, hafnium or aluminium, X is a ligand derived from acetylacetone or a peroxo ion; a is a number between 1 and 2.5; b is a number in the range from 1 to 2. Reactive compositions containing the catalyst composition are also described.

Abstract: Provided are a catalyst mixture and also a method for the production of a polyester melt with high viscosity, the granulate obtained therefrom having an intrinsic viscosity of >0.70 dl/g and an L* color >70 and the b* color being between ?5 and +5. The catalysts being used during the production are not based on heavy metals but on titanium compounds. Also no components of catalysts based on heavy metal are added. The granulate can be processed further in any way, e.g. to form bottles, containers, films, foils or fibers.

Abstract: A method is disclosed herein for the preparation of polytrimethylene terephthalate with sustained-release crystallinity. The method reduces crystallization rate and crystallinity-saturation ratio of polytrimethylene terephthalate during spinning, through addition of a third monomer during the esterification reaction step. The third monomer acts as copolymerization component generating intermolecular steric hindrance; the identity of which selects from one or more as combinations of the following: trimellitic anhydride, non-para aromatic dicarboxylic acid, C4-C10 aliphatic dicarboxylic acid having branched chains or naphthenic group and C3-C10 aliphatic dihydric alcohol having branched chains or naphthenic group, the molar ratio of carboxyl to hydroxyl is 1:1.16˜1.85, with the third monomer constituting 0.5˜6.5% of the total weight of the beginning raw materials.

Abstract: Biodegradable compositions containing an aliphatic-aromatic copolyester. Methods of making the compositions and articles made from the compositions.

Abstract: Biodegradable compositions containing an aliphatic-aromatic copolyester. Methods of making the compositions and articles made from the compositions.

Abstract: A method for preparing high shrinkage PTT copolyester, comprising: adding starting raw materials into a reaction kettle and adding an esterification catalyst to carry out esterification reaction at 220° C.˜260° C. under 0.05˜0.30 MPa and completing the reaction when there being no water produced: adding polymerization catalyst into the reaction system and carrying out the polymerization reaction at 240° C.˜280°C. to get polytrimethylene terephthalate. The starting raw materials consists of 1,3-propylene glycol, terephtalic acid, a third monomer, a fourth monomer and a fifth monomer.

Abstract: A method is disclosed herein for the preparation of modified poly (1,3-propanediol terephthalate). The method comprises adding linear polyester with average molecular weight of 800˜3000 and polyethylene glycol with average molecular weight of 200˜2000 into polymerization monomers before polymerization reaction, wherein the linear polyester is a polymer obtained by reaction of C3˜C10 straight chain aliphatic dicarboxylic acid or 1,4-cyclohexane diformic acid with C2˜C10 straight chain aliphatic diol or 1,4-cyclohexane dimethanol; the linear polyester is 0.5%˜6% of the mass of polymerization monomers; the polyethylene glycol is 0.5%˜8.5% of the mass of polymerization monomerss.

Abstract: Method for producing polyesters using titanium atrane catalysts is disclosed. Also disclosed are methods for making the titanium atrane catalysts. The titanium atrane catalysts are useful as esterification and/or polycondensation catalysts, have similar activity, color and byproduct formation as conventional catalyst systems, but with reduced toxicity and regulatory concerns.

Abstract: The invention relates to methods and systems for preparing macrocyclic polyester oligomer (MPO) directly from monomer via heterogeneous catalysis, rather than by depolymerizing a polyester. For example, in an exemplary embodiment, cyclic poly(butylene terephthalate) (cPBT) is produced by reacting butanediol (BDO) and dimethylterephthalate (DMT) in an organic solvent—for example, ortho-dichlorobenzene (oDCB). The mixture flows over (or otherwise contacts) the catalyst-coated fiberglass or silica gel, e.g., which is packed in a column or bed. MPO is produced in the reaction mixture, while residual linears and catalyst residue remain in the column/bed.

Abstract: A toner for an electrophotographic image forming process or an electrostatic printing process, and a polyester resin for the toner are disclosed. The polyester resin comprises: acid components including 70 to 96 mol % of aromatic dibasic acid component, 3 to 20 mol % of cycloaliphatic dibasic acid component, and 1 to 10 mol % of trivalent or higher acid component; alcohol components including 10 to 50 mol % of cycloaliphatic diol component, 2 to 20 mol % of trihydric or higher alcohol component, and 30 to 88 mol % of aliphatic diol component; and a heat stabilizer.

Abstract: A catalyst composition comprises the reaction product of an alkoxide or condensed alkoxide of a metal M, selected from titanium, zirconium, hafnium, aluminium, or a lanthanide, an alcohol containing at least two hydroxyl groups, a 2-hydroxy carboxylic acid and a base, wherein the molar ratio of base to 2-hydroxy carboxylic acid is in the range 0.01-0.79:1. The composition is useful as a catalyst for esterification reactions, especially for the production of polyesters such as polyethylene terephthalate, polytrimethylene terephthalate and polybutylene terephthalate.

Abstract: The invention provides methods and systems for manufacturing low-acid polyalkylene terephthalate, for example, polybutylene terephthalate (PBT). The invention also provides methods and systems for preparing macrocyclic polyester oligomer (MPO) from low-acid polyalkylene terephthalate. Finally, the invention provides methods and systems for preparing MPO via reaction of a diol and a dialkyl ester in an organic solvent to form non-isolated, low-acid polyalkylene terephthalate which undergoes cyclization (depolymerization) to form MPO.

Abstract: Disclosed is a method for increasing the solid state polymerization (SSP) rates of metal catalyzed polyesters. The method comprises in a first step, reacting a dicarboxylic acid or a C1-C4 dicarboxylic diester with a diol at a suitable temperature and pressure to effect esterification or transesterification to prepare a precondensate and in a second step, reacting the precondensate to effect polycondensation at a suitable temperature and pressure to prepare a high molecular weight polyester and in a third step, further increasing the molecular weight and viscosity of the polyester under SSP conditions of a suitable temperature and pressure, where a metal catalyst is added in the first step or in the second step as a reaction catalyst, and where a certain phosphinic acid compound is added in the first step, in the second step or just prior to the third step. The polyester product exhibits low aldehyde formation during melt processing steps as well as excellent color.

Abstract: The present invention relates to a method for the continuous production of high-molecular polyesters by esterification of dicarboxylic acids and/or transesterification of dicarboxylic acid esters with diols and/or mixtures thereof in the presence of catalysts with formation of a prepolymer in a tower reactor and polycondensation thereof to form a high-molecular polyester in a polycondensation reactor, a prepolymer with >40 to 70 repeat units (DP) being produced in the tower reactor and this prepolymer being polycondensed in only one further reactor to form a polyester with >150 to 205 DP.

Abstract: A method for producing a catalyst for producing polyester by an esterification reaction or a transesterification reaction between a dicarboxylic acid or an ester-forming derivative thereof and a glycol, which comprises hydrolyzing an organic silicon compound and/or an organic aluminum compound and/or an organic zirconium compound in an organic solvent in which particles of a solid are dispersed thereby to form an inner coat layer either of an oxide of at least one element selected from silicon, aluminum and zirconium or of a composite oxide of at least two elements selected from silicon, aluminum and zirconium, and then hydrolyzing an organic titanium compound in the organic solvent in which the particles of a solid base having the inner coat layer thereon are dispersed thereby to form an outer coat layer of titanic acid on the inner coat layer of the particles of a solid base.

Abstract: The invention provides a polycondensation catalyst for producing polyester by an esterification reaction or a transesterification reaction between a dicarboxylic acid or an ester-forming derivative thereof and a glycol, the polycondensation catalyst being obtained by hydrolyzing a water soluble titanium compound in the absence of a water soluble alkali in an aqueous slurry in which particles of a solid base are dispersed thereby to form on the surface of the particles of the solid base a coat layer of titanic acid in a content of from 0.1 to 50 parts by weight in terms of TiO2 per 100 parts by weight of the solid base. The invention further provides a method for producing such a polycondensation catalyst, and polyester obtained using such a polycondensation catalyst.

Abstract: Polyester compositions, especially polyethylene terephthalate homopolymer and copolymers, are disclosed containing titanium catalysts and catalyst deactivator added late in the manufacturing processing having reduced acetaldehyde generation rates. The polyester compositions are low in free acetaldehyde, making them suitable for fabrication into beverage containers for relatively tasteless beverages such as bottle water. Furthermore, the polyesters are polymerized to a high inherent viscosity in reduced processing time, without the necessity of further polymerization in the solid state, and in the absence of acetaldehyde scavengers leading to polyester polymers having reduced color.

Abstract: The invention provides a method for producing a catalyst for producing polyester by an esterification reaction or a transesterification reaction between a dicarboxylic acid or an ester-forming derivative thereof and a glycol, the method comprising hydrolyzing an organic titanium compound in an organic solvent in which particles of a solid base are dispersed thereby to form a coat layer of titanic acid on the surface of the particles of a solid base.

Abstract: The present invention relates to a method for the continuous production of high-molecular polyesters by esterification of dicarboxylic acids and/or transesterification of dicarboxylic acid esters with diols and/or mixtures thereof in the presence of catalysts with formation of a prepolymer in a tower reactor and polycondensation thereof to form a high-molecular polyester in a polycondensation reactor, a prepolymer with >40 to 70 repeat units (DP) being produced in the tower reactor and this prepolymer being polycondensed in only one further reactor to form a polyester with >150 to 205 DP.

Abstract: Provided are a catalyst mixture and also a method for the production of a polyester melt with high viscosity, the granulate obtained therefrom having an intrinsic viscosity of >0.70 dl/g and an L* colour >70 and the b* colour being between ?5 and +5. The catalysts being used during the production are not based on heavy metals but on titanium compounds. Also no components of catalysts based on heavy metal are added. The granulate can be processed further in any way, e.g. to form bottles, containers, films, foils or fibres.

Abstract: A method for reducing organic carbon emissions from PBT-block-containing resins is disclosed. The method involves adding a titanium-catalyst deactivating compound to the resin after polymerisation.

Abstract: A method for producing a polyester resin composition C), which comprises melt-kneading a polyester resin (A) which satisfies the following formulae (1), (2) and (3) and a polyester resin (B) which satisfies the following formula (4): P1?10??(1) 0.1?Ge1?1.5??(2) 0.001?Ge1/P1?0.15??(3) 0?P2/Ti1?80??(4) provided that in the formulae (1), (2) and (3), P1 is the content (mol) of phosphorus atoms and Ge1 is the content (mol) of germanium atoms, per ton of the polyester resin (A), and in the formula (4), P2 is the content (mol) of phosphorus atoms and Ti1 is the content (mol) of titanium atoms, per ton of the polyester resin (B). A polyester resin composition (C) obtained by the method, and a molded product such as a film made from such a composition are also provided.

Abstract: The present invention relates to a process for producing PET based on titanium catalyst having acceptable properties for resin used in the production of bottles for beverages. More particularly the invention relates to a process in which the incoming pre-polymer temperature is higher than the final outlet temperature in the final melt phase polycondensation reactor.