Wearable Health Devices are proving to be extremely helpful for people to keep a check on their health conditions. People can monitor their status at a fitness level and also at the proper medical level. With already a number of smart products in the market and the surge in the implementation IoT and AI in the healthcare sector, it is safe to say that the future lies in virtual healthcare and Wearable Health Devices. The cover photo of this October 2019 issue is inspired by the editorial article "Wearable Healthcare Devices", by Dr. Ashutosh Tiwari.
Critical Association Concentration of Dansyl-Poly (acrylic acid) Synthetized by Redox Polymerization Followed by an Esterification in Aqueous Solution: Spectrophotometric and Tensiometric Studies
1Chemistry Department, Faculty of Science, University of Benghazi, Benghazi, Qar Yunis, Libya
Adv. Mater. Lett., 2019, 10 (10), pp 741-745
Publication Date (Web): May 10, 2019
Copyright © IAAM-VBRI Press
In the present work, the critical concentration for self-assembly of dansyl-polyacrylic acid (DANS-PAA) in aqueous solution has been characterized by a combination of spectrophotometric and tensiometric techniques, number average molar mass, degree of polymerization, and average number of bonds were also determined. The normalized absorbance value for DANS-PAA (10-4 wt%) as a function of PAA concentration was at maximum below a critical self-assembly concentration (CAC) of 0.0005 g·mL−1 and decreased dramatically with PAA concentration above this CAC. This supposes that upon adding more polymer, assembly occurs in a short concentration range about 0.0005 g·mL−1. Similarly, surface tension measurements for DANS-PAA decreased markedly with concentration after a threshold of around 0.0005 g·mL−1, above which it remained constant at ca. 20 dyne·cm−1. Consequently, the binary techniques produced an equivalent estimation of the CAC. Additionally, surface tension studies showed that the DANS-PAA polymer miscible with water caused surface tension to decrease by 49 % over a concentration range of 0 to 0.0014 g·mL−1, whereas marked reduction in surface tension (33 %) upon adding PAA, and slight decreasing (7%) was recorded upon adding acrylic acid monomer (AA) to water. © VBRI Press.
Polyacrylic acid, dansyl-poly (acrylic acid), redox polymerization, absorbance, surface tension