Oscillatory Discharging Behavior of a Pyridine-Based Polymer Blend Gel

Our investigation of molecular binding in a unique, concentrated polymer solution has, to date, been unable to adequately explain its remarkably flexible response to external perturbation.^1,2 During the last two years, the blend of poly(4-vinyl pyridine)/poly(4-vinyl pyridine – co – butylmethacrylate), gelled in pyridine, has been shown to be supersensitive to both heat and IR-radiation¹, with markedly different relaxation times^3. However, one fundamental question was indeed answered – the gel contains multiple forms of hydrogen bonding due to the self-protonation of the pyridine side-chain.⁴ The suggested source of the bi-functional sensitivity is the combination of ester-group oxygen / protonated side-chain and NH….N structural group complexes.

Here we present an additional aspect of gel functionality. Following poling of the gel to achieve saturation resistance, electrical oscillations appear during gel discharging (Figure 1). The oscillations appear at three different frequencies: 0.02Hz ; 0.3Hz; 0.7Hz. The amplitude of the slow and intermediate oscillations is approximately 1.00 -1.25 V and that of the more rapid oscillations, approx. 0.12 V. Interestingly, this type of behavior mimics that observed during charge transfer in neuronal axons. A possible explanation as well as its significance will be discussed.

Figure 1. Voltage oscillations of the polymer blend, observed during discharging; insert – sketch of the electrical scheme (RC of capacitor is about 0.1).

^{1. .United States Patent Application No.14/004, 801 “Polymeric compositions and uses thereof” Our Ref:2244875 RB/lid (2016).}

^{2. E. Vaganova et al, “White light and heat Sensitivity in a Pyridine-Based Polymer Blend” J. Phys Chem. C 2012, 116, 25028-25033.}

^{3. YouTube Evgenia Vaganova}

^{4. E. Vaganova et al. “Photoinduced proton transfer in a pyridine Based Polymer Gel” . J Phys Chem B, 2010, 114, 10728-10733.}