Polyvinyl alcohol bearing coumarin has the ability to be cross-linked under the illumination of 365 nm ultraviolet light,and the cross-linked points can be photocleavaged after being illuminated with UV light of 254 nm,while the photocleavaged product still has cross-linking ability.Using this property,this paper designed shape memory polymers with repeatedly reconfigurable initial shapes.The effects of grafting rate,irradiation time,and the film thickness on the material shape memory properties were studied.It is found that the higher grafting rate of coumarin,the higher shape recovery ratio of the shape memory polymer after fixation.The initial shape fixation and thermal recovery performances of the shape memory polymers are greatly affected by the irradiation time of 365 nm ultraviolet light and the film thickness.By adopting an appropriate ultraviolet irradiation time,high grafting efficiency,and a thinner membrane,shape memory polymers could be produced with a shape recovery rate above 70％,allowing for repeatedly reconfigurable initial shapes.This study validates the feasibility of the above design method and provides a new research approach for preparing polymers with reversible cross-linking properties.
万方数据
维普
