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.
Synthesis and characterization of thermally stable flame retardant thermoplastic polyphosphazenes
Krishna Pratap Singh1, 2*, Anuradha Mishra2, Nand Kumar1, Trilok Chand Shami1
1Defence Materials & Stores Research and Development Establishment, DMSRDE (DRDO), G. T. Road, Kanpur-208013, India
2Gautam Buddha University, Greater Noida-201312, India
Adv. Mater. Lett., 2019, 10 (10), pp 724-730
Publication Date (Web): May 16, 2019
Copyright © 2019 VBRI Press
Corresponding author: Tel: 09415622375; E-mail: firstname.lastname@example.org
Different types of functionalized thermoplastic polyphosphazenes such as poly(bis(furfuroxy)phosphazenes) (PBFP), poly(bis(1-adamantanemethylamine)phosphazenes) (PBAP) and poly(bis(cyanophenoxy)phosphazenes) (PBCP) were synthesized and further characterized to study their flame retardant properties. Structural characterizations were carried out by using GPC, FTIR, 1H & 31P NMR and wide angle XRD. Beside this, the solubility behaviour of these synthesized polyphosphazenes was checked in various protic and aprotic solvents. Thermal analysis and combustion properties of synthesized polyphosphazenes were investigated using thermogravimetric analysis (TGA), differential scanning calorimetry, UL-94 (vertical burning test) and cone calorimetry. The Limiting Oxygen Index values of synthesized polyphosphazenes were also determined from their % char yield obtained in TGA. It was found that the LOI value was highest for PBCP and lowest for PBAP amongst all substituted polyphosphazenes. Further, all the polymeric samples showed high flame retardancy with UL-94 V-0 rating. The water uptake property of synthesized polyphosphazene polymers was also invested by measuring their water contact angles which showed that all the polymers were hydrophobic in nature with their water contact angles in the range of 137o to 141o. © VBRI Press.
Functionalized polyphosphazenes, limiting oxygen index, flame retardancy, cone calorimetry, UL-94