US 12,365,767 B2
Synthesis of polyester based polymers without use of organic solvents
Praveen Thoniyot, Singapore (SG)
Assigned to Agency for Science, Technology and Research, Singapore (SG)
Appl. No. 17/438,773
Filed by Agency for Science, Technology and Research, Singapore (SG)
PCT Filed Apr. 9, 2020, PCT No. PCT/SG2020/050218
§ 371(c)(1), (2) Date Sep. 13, 2021,
PCT Pub. No. WO2020/214089, PCT Pub. Date Oct. 22, 2020.
Claims priority of application No. 10201903383X (SG), filed on Apr. 15, 2019.
Prior Publication US 2022/0169801 A1, Jun. 2, 2022
Int. Cl. C08G 81/02 (2006.01); C08G 63/08 (2006.01); C08G 63/78 (2006.01); C08G 63/82 (2006.01)
CPC C08G 81/027 (2013.01) [C08G 63/08 (2013.01); C08G 63/78 (2013.01); C08G 63/823 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An organic solvent-free method of producing a polyester, the method comprising:
providing a mixture comprising at least one precursor of the polyester, wherein the at least one precursor is a liquid, wherein the at least one precursor comprises a caprolactone;
drying a gaseous inorganic acid to remove water from the gaseous inorganic acid; and
contacting the mixture, with the gaseous inorganic acid which is dried, to produce the polyester, wherein drying the gaseous inorganic acid is carried out prior to contacting the mixture with the gaseous inorganic acid and prior to any polymerization which renders the polyester.