315181-51-2Relevant academic research and scientific papers
Novel mechanism of fast relaxation of photo-induced anisotropy in a poly(malonic esters) containing p-cyanoazobenzene
Joo, Won-Jae,Shin, Hee-Deuk,Oh, Cha-Hwan,Song, Seok-Ho,Kim, Pill-Soo,Ko, Bong-Soo,Han, Yang-Kyoo
, p. 8848 - 8851 (2000)
The photo-induced anisotropy in a side-chain liquid crystalline poly(malonic esters) was investigated using the relaxational tests. The process showed an abnormal increase in the birefringence values after the decaying process. The related free volume effect was also reported as a new model considering the elastic forces between the polymeric film was proposed. The orientation with the side chain and the relaxation process was found to vary with the elastic forces.
Photoinduced birefringence in poly(malonic ester) containing p-cyanoazobenzene with photoexcitation of cis conformer
Joo, Won-Jae,Oh, Cha-Hwan,Song, Seok-Ho,Kim, Pill-Soo,Han, Yang-Kyoo
, p. 8322 - 8326 (2001)
Photoinduced birefringence in a poly(malonic ester) containing two symmetrical p-cyanoazobenzene groups has been investigated using two pumping beams with different wavelengths of 365 and 488 nm, which are assignable to the absorption wavelengths of trans
Influence of the backbone on photoinduced birefringence in a poly(malonic ester) containing p-Cyanoazobenzene
Joo, Won-Jae,Oh, Cha-Hwan,Han, Yang-Kyoo
, p. 5378 - 5381 (2002)
The influence of the backbone on the photoinduced birefringence was investigated in a poly(malonic ester) containing a p-cyanoazobenzene group as a side-chain. The photoinduced birefringence was successively measured in the fifteen cycles of the recording, relaxation, and erasing processes. The linearly polarized light, with a polarization direction of 45?° relative to the analyzer, was used as the pumping beam during the first five cycles, and the same pumping beam at negative 45?° was used during the next 10 cycles. When the polarization direction of the pumping beam was changed perpendicularly, a very interesting birefringence curve was observed in the recording and relaxation processes, which could be well explained by our model considering the reorientation of the backbone caused by the elastic force between the backbone and side-chain. Consequently, we confirmed the fact that the relaxation behavior of the photoinduced birefringence is closely associated with the reorientation of the backbone.
