English Abstract
Characteristics of Vulcanized EPDM Degradation in Ozone Water or Ozone/ Chlorine Water
Satoshi MIWA
Hiroaki KONDO
Hiroyuki ONTSUKA
Yoshito OHTAKE
Chemicals Evaluation and Research Institute, Japan Sugito-machi, Kitakatsushika-gun, Saitama, Japan
Nippon Gomu Kyokaishi,(2008),81(1),14-18 Original Paper in Japanese

The degradation behavior of vulcanized EPDM in ozone water (O3(aq)) or ozone/chlorine water (O3/Cl2(aq)) was investigated and characterized by ATR-FT-IR, GPC, and EPMA analysis.
The superficial layer of vulcanized EPDM was observed to be disrupted due to oxidative shortening of EPDM polymer chains by O3(aq) or O3/Cl2(aq). Furthermore, EPDM treated in O3/Cl2(aq) contained a higher proportion of decomposition products than that treated in O3(aq). This may be a result of the synergetic effect on acceleration of oxidation by chlorine and reaction with radical oxygen generated from O3/Cl2(aq).
As an additional experiment, degradation behavior of carbon black- and silica-compounded EPDM's in O3/Cl2(aq) was investigated.
In this case, the latter material was less damaged by oxidation than the former one.

(Accepted on June 28, 2007)

(Received on November 13, 2007)

Ozone Water, Ozone/Chlorine Water, EPDM, Oxidative Degradation, FT-IR, EPMA Line Analysis