Abstract: A method for producing an oligomeric polyethylene terephthalate (PET) substrate for use in a recycled PET (rPET) manufacturing process comprises adding recycled bis-hydroxylethyleneterephthalate (rBHET) or a higher molecular weight oligomer derived from rBHET and water to a reaction zone and reacting the rBHET and water in the reaction zone to produce an oligomeric PET substrate represented by the Formula (I): wherein R1 is a carboxyl end group or a hydroxyl end group, R2 is a carboxyl end group or a hydroxyl end group, and n is a degree of polymerisation (Dp).

Abstract: A method for producing an oligomeric PET substrate for use in a rPET manufacturing process comprises reacting recycled bis-hydroxylethyleneterephthalate (rBHET) or a higher molecular weight oligomer derived from rBHET, with PTA to produce an oligomeric PET substrate represented by Formula (I), wherein R1 is a carboxyl end group or a hydroxyl end group, R2 is a carboxyl end group or a hydroxyl end group, and n is a degree of polymerisation.

Abstract: A method for improving L* color of polyethylene terephthalate polymer, the method including bis-hydroxylethyl-eneterephthalate being polycondensed to produce said polyethylene terephthalate polymer in a polyethylene terephthalate manufacturing process, and wherein said process requires an antimony-containing catalyst, the method comprising the steps of: i) adding said antimony-containing catalyst at a temperature in a range of a melting point of said BHET to an upper temperature of 220° C.; and ii) exposing said BHET in a molten state to glycol removal before addition of said antimony-containing catalyst.

Abstract: A method for producing an oligomeric polyethylene terephthalate (PET) substrate for use in a recycled PET (rPET) manufacturing process, comprising (i) adding recycled bis-hydroxylethylenete rephthalate (rBHET) and an under-esterified purified terephthalic acid (PTA) oligomer to a reaction zone; and ii) reacting the rBHET and the under-esterified PTA oligomer in the reaction zone to produce an oligomeric PET substrate represented by the formula (I), wherein R1 is a carboxyl end group or a hydroxyl end group, R2 is a carboxyl end group or a hydroxyl end group, and n is a degree of polymerisation (Dp).

Abstract: The disclosed process relates to an improved process for manufacturing THF from a reaction mixture comprising BDO in the presence of an acid catalyst in a reaction vessel comprising a distillation reaction zone, wherein the acid catalyst is suspended in a vapor-rich region in the distillation reaction zone.

Abstract: The invention relates to a thermosiphon esterifier design comprising a riser baffle in the vapor separator. Advantageously, the thermosiphon esterifier design can provide an economic benefit as compared with traditional thermosiphon esterifier designs. Methods of using the thermosiphon esterifier design in a system for the production of polyethylene terephthalate are also described.

Abstract: The invention relates to recycling steam at elevated temperature and/or pressure generated within a thermosiphon esterifier design comprising a riser baffle in the vapor separator. Advantageously, the thermosiphon esterifier design can provide steam that can be employed in various additional processes and can thus provide an overall energy savings in operating the thermosiphon esterifier. Methods of using the steam are also described.

Abstract: Disclosed are processes and systems for manufacturing polyethylene terephthalate (PET) and pre-polymer. The processes and systems use a variable pressure drop up-flow-pre-polymerizer configuration. The pressure profile in the UFPP can be selected to beneficially change the relative reaction rates of the polymerization and esterification reactions. This design maximizes the esterification carried out in the UFPP, while still producing a pre-polymer with the optimum carboxyl end groups concentration (e.g., about 30? equiv./g to 60? equiv./g) to maximize finisher productivity. This can result in a reduction of the size and cost of the esterifier required for a given plant throughput.

Abstract: The present invention provides an improved process for converting a diester of polyether polyol, e.g., PTMEA, to the corresponding dihydroxy product, e.g., polytetramethylene ether glycol (PTMEG) continuously in a reaction zone, such as, for example, a reactive distillation system, for achieving virtually complete conversion of PTMEA to PTMEG, and recovery of PTMEG free of unreacted or unconverted PTMEA and alkanol ester by-product.

Abstract: The invention relates to a method for producing a high molecular weight polyethylene terephthalate (PET) via a solid state polymerization system. The method comprises using an acid catalyst to effectuate the conversion of acetaldehyde present within the system to 2-methyl-1,3-dioxolane, which can be readily removed. The invention also relates to PET prepared via this process, which can advantageously exhibit low levels of acetaldehyde.

Abstract: The present invention relates to a process for producing a polyester comprising: (a) forming a polyester with an intrinsic viscosity of at least about 0.65, wherein said forming of the polyester comprises use of a catalyst; and (b) adding a phosphorous compound to the polyester after the forming of step (a), wherein said phosphorous compound comprises at least one member selected from the group consisting of trialkyl phosphate, trialkyl phosphonoacetate, monoalkyl phosphate, dialkyl phosphate, trialkyl phosphite, triaryl phosphite, tris alkylaryl phosphite, and mixtures thereof. The present invention also includes compositions produced by process of the present invention and articles comprising those compositions.

Abstract: The present invention relates to a process for producing a polyester comprising: (a) forming a polyester in a melt phase having an intrinsic viscosity of about 0.65 or more, provided that said forming is not by solid state polymerization; and (b) adding an anhydride to the polyester during the melt phase. The present invention also includes articles comprising a composition produced by processes of the present invention.

Abstract: An improved process for recycling unspent diol removed from a polyester manufacturing process wherein the diol is captured, hydrogenated, and recycled so that the final polyester product has improved color over polyesters produced using other recycled diols.

Abstract: A process that can be used as catalyst in esterification, transesterification or polycondensation is disclosed, which comprises a stable solution comprising (a) titanium in the form of a titanium ?-hydroxycarboxylic acid or its salt, (b) a C1-C6 carboxylic acid, and (c) zinc in the form of a water-soluble zinc salt, and (d) water. Also disclosed is an esterification, transesterification or polycondensation process, which comprises contacting, in the presence of the solution process, an organic acid or its ester or its salt with an alcohol, optionally in the presence of a phosphorus compound, an organic or inorganic toning agent such as cobalt acetate, or combinations thereof.

Abstract: A process that can be used as catalyst in esterification, transesterification or polycondensation is disclosed, which comprises a stable solution comprising (a) titanium in the form of a titanium &agr;-hydroxycarboxylic acid or its salt, (b) a C1-C6 carboxylic acid, and (c) zinc in the form of a water-soluble zinc salt, and (d) water. Also disclosed is an esterification, transesterification or polycondensation process, which comprises contacting, in the presence of the solution process, an organic acid or its ester or its salt with an alcohol, optionally in the presence of a phosphorus compound, an organic or inorganic toning agent such as cobalt acetate, or combinations thereof.