《Driving Quick and Large Amplitude Contraction of Viologen-Incorporated Poly-L-Lysine-Based Hydrogel by Reduction》 was written by Wang, Bo; Tahara, Hironobu; Sagara, Takamasa. Related Products of 17696-11-6This research focused onviologen functionalized polylysine hydrogel reduction induced contraction; actuation; contraction and re-expansion; hydrogel; redox; viologen. The article conveys some information:
A glutaraldehyde-crosslinked poly-L-lysine-based hydrogel with pendant viologens was synthesized with various [viologen unit]/[Lys unit] ratios. The hydrogel with the ratio of 25% had (i) a water content of 95.8%, (ii) unbound viologen unit was absent, and (iii) lyophilized gel showing porous structure was rewettable. The hydrogel in contact with a gold, glassy carbon, pyrolytic graphite, or ITO electrode was electroactive, showing voltammetric responses involving diffusion process. Occurrence of electron transfer between viologen sites was verified by ESR measurements. The electroreflectance spectrum indicated significant dimerization of one-electron-reduced forms, viologen radical cations. Reduction of the hydrogel by dithionite showed a 93% volume decrease, being near to the water content, at 100 s and finally 97% contraction at 380 s. The initial rate of contraction was 0.02 s-1, and the swelling weight ratio was > 17. The contraction rate was much faster than that observed when adding of redox-inactive salts in the outer medium. Recovery by reoxidation was relatively sluggish even when O2-saturated water was used. The quick and large-amplitude contraction with removal of water from the gel body should be the consequence of permeability of reductant, interchain π-stacking of one-electron-reduced forms (viologen monoradical monocation), desolvation of viologen upon reduction, electron hopping between viologen units and its acceleration with contraction, and effective osmotic pressure difference. The experimental process involved the reaction of 8-Bromooctanoic acid(cas: 17696-11-6Related Products of 17696-11-6)
8-Bromooctanoic acid(cas: 17696-11-6) acid is used in the synthesis of 8-(N-Methyl-4,4′-bipyridinyl)- octanoic acid. 8-Mercaptooctanoic acid was prepared from 8-bromooctanoic acid.Related Products of 17696-11-6
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary