Most polymeric materials

including plastics、rubbers、fibers、coatings and so on

underwent photoaging when used outdoors and their services lifes were thus cut down.In order to protect effectively the polymeric materials from photo-deterioration

the mechanisms of photo-aging and photostabilization of polymers had been studied widespreadly and several types of light stabilizers developed successively.But since the photo-aging of polymers had been being made more and more complicated by the continuously extended ranges of use and deteriorated environment and their photo-protection becoming more and more difficult

the study of the mechanisms of photo-aging and photostabilization of polymers and development of light stabilizers were very active all the way at home and abroad.In the second part of this paper

the action mechanisms of light stabilizers were expounded and the advances in development of light stabilizers were reviewed.