Photogenerated hydroperoxides of EPDM rubbers and their characterization

Abstract

Three different ethylene/propylene/diene (EPDM) rubbers were allowed to react with singlet oxygen. This reaction leads to the production of polymeric pendant hydroperoxides only in one case. Terpolymer ethylene/propylene/5‐ethylidene‐2‐norbornene reacts with singlet oxygen and isolated and associated secondary hydroperoxides are formed. Anthracene was used as a sensitizer for production of singlet oxygen under 365‐nm irradiation. The course of hydroperoxide formation was similar in the solid state as well as in the toluene solution. Reactivity of hydroperoxides prepared was tested in their reaction with gaseous dimethyl sulfide (DMS). Both the isolated and associated hydroperoxides react with DMS by dual fast and slow process. Fast process is more significant in the case of the isolated hydroperoxides. © 1995 John Wiley & Sons, Inc.

Photografting on Ethylene/Propylene/5-Ethylidene-2-norbornene Rubber Initiated by Photogenerated Hydroperoxides

“…In our previous paper 1 we have shown that the ratio of isolated to associated hydroperoxides was 1:3 on the basis of IR spectra. So, we have the starting material containing 75% of associated hydroperoxides.…”

“…Initially the rubber was precipitated from toluene solution into methanol to remove possible additives. Preparation of hydroperoxides in the solid state (film) or in the solution is described in ref . Hydroperoxide concentration was measured from IR spectra directly or after derivatization reaction with gaseous NO and by iodometric analysis.…”

“…In a recent paper 1 we have shown that modification of terpolymer ethylene/propylene/ethylidenenorbornene (EPDM) can be easily performed with singlet oxygen. This modification leads to the production of polymeric pendant hydroperoxides.…”

Photo-hydroperoxidation and grafting of polyoctenamer. Access to new polymeric-hindered amine stabilizers

“…The formation of VIST-OOH stopped after conversion of anthracene to 9,10-anthracene endoperoxide. 4 This means that hydroperoxides 07-18-97 01:29:58 polcal W: Poly Chem duction stops after anthracene consumption (the same rate for nonextracted and extracted film after 120 min of irradiation). There are several reports in the literature concerning the mutual interactions of oxygenated species such as hydroperoxides, ketones, and peroxides.…”

“…ethylene / propylene / 5 -ethylidene -2 -norbornene (EPDM). 4,5 Anthracene was used as a sensitizer for production of singlet oxygen under 365 nm irradia-clic ring content. This rubber has a regular strucExtraction was performed by dipping the film containing the additives into methanol for 60 min at ture [{(CH 2 ) 6 {CH|CH{] n , with a double bond at every eight C-atom.…”