| Popis: |
Specific features of degradation by electrochemical reduction have been investigated with polyethylene, polytetrafluoroethylene, and a copolymer ethylene-vinyl acetate which contain side groups of different electrochemical activity. In contrast to polyethylene, polytetrafluoroethylene and the ethylene-vinyl acetate copolymer, subject to prolonged cathodic polarization, are reduced and degraded at the three-phase boundary polymer-electrode-solution. The degradation by electrochemical reduction of polytetrafluoroethylene and of the copolymer is accompanied by a loss of weight and formation of conjugated double bonds in the main chain. The stability of the investigated polymers to electrochemical reduction decreases in the series polyethyelene⪢ethylene-vinyl acetate copolymer > polytetrafluoroethylene. |
