# US 8,772,436 B2 · Process for making thermoplastic polyesters > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,772,436 B2 - Document ID: US8772436B2 - Status: Granted - Kind: B2 - Application number: 13/256,540 - Filed: 2010-03-15 - Published: 2012-01-12 - Granted: 2014-07-08 - Earliest claimed: 2009-03-18 - Assignees: Saudi Basic Industries Corporation - Applicants: Zahir Bashir - Inventors: Zahir Bashir - Web page: https://patentgrep.com/patent/US8772436B2 ## CPC - C08G 63/85: Germanium, tin, lead, arsenic, antimony, bismuth, titanium, zirconium, hafnium, vanadium, niobium, tantalum, or compounds thereof {(C08G63/823 takes precedence)} - C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS ## 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. ## Claims ### Claim 1 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 an inorganic nano-layered titanate in exfoliated form as a catalyst. ### Claim 2 (depends on 1) The process according to claim 1, wherein the inorganic nano-layered titanate is present in pre-exfoliated form. ### Claim 3 (depends on 2) The process according to claim 2, wherein the titanate has been added in the form of an aqueous suspension. ### Claim 4 (depends on 2) The process according to claim 2, wherein the titanate has been added as dried or semi-wet titanate nanotubes. ### Claim 5 (depends on 1) The process according to claim 1, wherein the titanate has a layer charge-density in the range of 2 to 4 nm−2, as determined by the Sasaki method. ### Claim 6 (depends on 1) The process according to claim 1, wherein the inorganic nano-layered titanate is at least one member selected from the group consisting of titanates with lepidocrocite structure of formula HxTi2−x/4□x/4O4.H2O wherein x is in the range of 0.5 to 1.2 and □ is a vacancy at a titanium site. ### Claim 7 (depends on 6) The process according to claim 6, wherein x is in the range of 0.67 to 0.73. ### Claim 8 (depends on 1) The process according to claim 1, wherein the titanate is at least one member selected from the group consisting of H0.7Ti1.825□0.175O4.H2O, H0.7Ti1.65Mg0.35O4.yH2O, H0.8Ti1.6Ni0.4O4.H2O and H0.8Ti1.2Fe0.8O4.H2O. ### Claim 9 (depends on 1) The process according to claim 1, wherein the titanate plate size is in a range of 0.8 to 6 μm and thickness dimension is 100-900 nm. ### Claim 10 (depends on 1) The process according to claim 1, wherein Ti is present in an amount of 40 to 150 ppm based on the polyester. ### Claim 11 (depends on 1) The process according to claim 1, further comprising an antimony compound as co-catalyst. ### Claim 12 (depends on 1) The process according to claim 1, further comprising a phosphorous compound as stabilizer. ### Claim 13 (depends on 12) The process of claim 12, wherein the phosphorous compound is at least one selected from phosphoric acid, triethyl phosphate and triethyl phosphonoacetate. ### Claim 14 (depends on 1) The process according to claim 1, wherein the polyester is polyethylene terephthalate, the dicarboxylic acid is terephthalic acid and the diol is ethylene glycol. ### Claim 15 A method of using an inorganic nano-layered titanate, comprising: contacting the inorganic nano-layered titanate with reactants in esterification and polycondensation reactions to produce a product, wherein the inorganic nano-layered titanate is in exfoliated form as a catalyst. ### Claim 16 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 an inorganic nano-layered titanate in exfoliated form as a catalyst; wherein the titanate has a layer charge-density in the range of 2 to 4 nm−2, as determined by the Sasaki method; and wherein the inorganic nano-layered titanate is at least one member selected from the group consisting of titanates with lepidocrocite structure of formula HxTi2−x/4□x/4O4.H2O wherein x is in the range of 0.5 to 1.2 and □ is a vacancy at a titanium site. ### Claim 17 A method of using an inorganic nano-layered titanate, comprising: contacting the inorganic nano-layered titanate with reactants in esterification and polycondensation reactions to produce a product, wherein the inorganic nano-layered titanate is in exfoliated form as a catalyst; wherein the titanate has a layer charge-density in the range of 2 to 4 nm−2, as determined by the Sasaki method; and wherein the inorganic nano-layered titanate is at least one member selected from the group consisting of titanates with lepidocrocite structure of formula HxTi2−x/4□x/4O4.H2O wherein x is in the range of 0.5 to 1.2 and □ is a vacancy at a titanium site.