Patent · US Expired

Depolymerization of condensation polymers involving a pre-molecular weight reduction step

US4620032A · kind A · utility

46Cited by
1References
25Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1984
Grant dateOct 28, 1986
Priority date
Expiry dateDec 11, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C51/09
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

There is disclosed a process for reducing the reaction time in the hydrolysis of a condensation polymer wherein molten condensation polymer is intimately admixed with a depolymerizing agent which is either (i) one of the products resulting from the complete hydrolytic depolymerization of the condensation polymer; or (ii) water. The depolymerization agent is present in the mixture in an amount which is less than the weight of the condensation polymer and the materials are intimately admixed for a time sufficient that the molecular of the condensation polymer is reduced by at least 50%. The treated condensation polymer of lower molecular weight is thereafter subjected to neutral hydrolysis. In addition to decreasing the overall time required to effect complete hydrolytic depolymerization, this process additionally permits the use of a smaller hydrolysis vessel, thereby reducing the fabrication cost of the hydrolysis unit.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.