Rheological behaviour and antibacterial activities of MWCNTs/ lyotropic liquid crystals based nanocolloids

ABSTRACT

Nanocolloids are prepared via doping of 0.015 mg and 0.030 mg multiwalled carbon nanotubes (MWCNTs) in the lyotropic phases of cetylpyridinium chloride (CPC)/glycerol (2:98, 5:95, 10:90 and 20:80 wt%/wt%). Nanocolloids are characterised by polarising optical microscopy (POM) for structural confirmations. No phase change has been observed in any sample with MWCNTs doping concentrations. Non-doped lyotropic phases and nanocolloids are studied for static and dynamic rheology, frequency sweep and thixotropic behaviour. Shear rheology infers about the shear thinning to Newtonian till 10:90 CPC/glycerol concentration and shear thickening to Newtonian for 20:80 wt%:wt% system. The studied systems follow the nematodynamic concept. The frequency sweep test infers that lyotropic mesophases and nanocolloids exhibit viscoelastic behaviour. Further, the thixotropic measurements infer the weak gel nature of mesophases and nanocolloids. Lyotropic phases and nanocolloids show strong inhibition properties against the gram-negative Escherichia Coli (E. Coli.) bacteria. Lyotropic phases and nanocolloids can be used in microbial and lubrication applications. The unique antibacterial properties of these systems make them suitable for use in medical and pharmaceutical devices to prevent the spread of infection.

GRAPHICAL ABSTRACT

KEYWORDS:

• Lyotropic liquid crystals
• nanocolloids
• non-Newtonian fluid
• viscoelastic behaviour
• antibacterial study

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work has been financially supported by the Science and Engineering Research Board (SERB), India [Project Number: EMR/2016/005591].