Title: On the Mechanism of the Steady-State Gamma Radiolysis-Induced Scissions of the Phenyl-Vinyl Polyester-Based Resins

Journal Article · · Frontiers in Chemistry

The major societal problem of polymeric waste necessitates new approaches to break down especially challenging discarded waste streams. Gamma radiation was utilized in conjunction with varying solvent environments in an attempt to discern the efficacy of radiolysis as a tool for the deliberate degradation of model network polyesters. Our EPR results demonstrated that gamma radiolysis of neat resin and in the presence of four widely used solvents induces glycosidic scissions on the backbone of the polyester chains. EPR results clearly show the formation of alkoxy radicals and C-centered radicals as primary intermediate radiolytic products. Despite the protective role of the phenyl groups on the backbone of the radiation-induced polyester chains, the radiolytic-glycosidic scissions predominate. Among the following three solvents used in this study (water, isopropyl alcohol, and dichloromethane), the highest radiolytic yield of glycosidic scission was achieved using water. The •OH radicals produced in the radiolysis of phenyl unsaturated polyester aqueous suspensions very rapidly abstract H atoms from the methylene group, which is followed by a very rapid glycosidic scission. The lowest glycosidic yield was found in the dichloromethane solutions of these polyester resins due to scavenging by the fast electron capture reactions.

Research Organization:
Brookhaven National Laboratory (BNL), Upton, NY (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
AC05-00OR22725; SC0012704
OSTI ID:
1839328
Report Number(s):
BNL-222530-2021-JAAM; 803347
Journal Information:
Frontiers in Chemistry, Journal Name: Frontiers in Chemistry Vol. 9; ISSN 2296-2646
Publisher:
Frontiers Media SACopyright Statement
Country of Publication:
Switzerland
Language:
English

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