Abstract: Considering the polymer solution viscosity loss of polymer flooding,the effect of hydroquinone,triethylamine,ferrous ions,sulfur ions and sulfate reducing bacteria on low concentration partial hydrolyzed polyacrylamide solution is investigated with capillary viscometer method.The results indicate only the low concentration triethylamine can keep the partially hydrolyzed polyacrylamide solution viscosity stable,the others will make the polyacrylamide solution degraded,resulting in the drastic decrease of polyacrylamide solution viscosity during a short period.This paper also presents the degradation mechanism of hydroquinone,triethylamine,ferrous ions,sulfur ions and sulfate reducing bacteria on low concentration partial hydrolyzed polyacrylamide solution.Besides,the fluoscrecne picture is used to illustrate that the PHPAM solution degradation could be fastened by sulfate reducing bacteria.All the above will provide a theoretical and technical basis for the polymer flooding technique.

Key words: polyacrylamide, dilute solution, viscosity loss, reducing substance, sulfatereducing bacteria