Page 243 - Polymer-based Nanocomposites for Energy and Environmental Applications

Polymer nanocomposites for sensor devices 215

O-Xylene

Toluene Ethyl benzene

Benzene

Fig. 7.6 Graphic mechanism of the sensor mechanism.
Reproduced from Das R, Bandyopadhyay R, Pramanik P. Efficient detection of volatile
aromatic hydrocarbon using linseed oil-styrene-divinylbenzene copolymer coated
quartz crystal microbalance. RSC Adv 2015;5:59533–40, with permission from Royal Society
of Chemistry.

from only linseed oil has the property of excellent hydrophobic nature, but due to
its softness of matrix, it is unable to retain molecular pores. Due to higher rigidity
of the molecular matrix, very less volume is present for the accommodation of guest
hydrocarbon vapors obtained from polymer obtained from monomer units of styrene
and divinylbenzene. To improve the availability of molecular pores and physical
adsorption on the QCM surface was confirmed from the fast response and recovery
time of developed sensor.
For the detection of aliphatic amine vapor, the polymerized castor-oil-based QCM
sensors were adopted [35]. The presence of dOH group in the triglyceride chain of
the castor oil has introduced the remarkable property of detection of amines without
having any acid group in the chain. It was noticed that a small change of structure of
triglycerides introduced a new class of the detection system. The polymerization pro-
cess was optimized for best detection by using different percentage of benzoyl perox-
ide in the solution. The sensitivity and selectivity of the sensors were determined from
the least-square parameters of the calibrated curve and are found to be satisfactory.
Further, in another study [36], it also observed the polymerized tung-oil-coated
QCM sensors for the detection of organic vapors such as methylamine, ethylamine,
diethylamine, triethylamine, and tert-butylamine. This polymeric film was showing
higher sensitivity toward aliphatic amine vapor than other volatile compounds. The
incorporation of dOH group to the triglyceride chain was confirmed from the FTIR