title: Ultrasound-based treatment approaches for intrinsic viscosity reduction of polyvinyl pyrrolidone (PVP).
abstract: The present work deals with achieving viscosity reduction in polymer solutions using ultrasound-based treatment approaches. Use of simple additives such as salts, or surfactants and introduction of air at varying flow rates as process intensifying parameters have been investigated for enhancing the degradation of polyvinyl pyrrolidone (PVP) using ultrasonic irradiation. Sonication is carried out using an ultrasonic horn at 36 kHz frequency at an optimized concentration (1%) of the polymer. The degradation behavior has been characterized in terms of the change in the viscosity of the aqueous solution of PVP. The intrinsic viscosity of the polymer has been shown to decrease to a limiting value, which is dependent on the operating conditions and use of different additives. Similar extent of viscosity reduction has been observed with 1% NaCl or 0.1% TiO2 at optimized depth of horn and 27°C, indicating the superiority of titanium dioxide as an additive. The combination of ultrasound and ultraviolet (UV) irradiation results in a significantly faster viscosity reduction as compared to the individual operations. A kinetic analysis for the degradation of PVP has also been carried out. The work provides a detailed understanding of the role of the operating parameters and additives in deciding the extent of reduction in the intrinsic viscosity of PVP solutions.
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India.
authors.forename: Indrajeet A
authors.initials: IA
authors.lastname: Pawar
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India.
authors.forename: Prathmesh J
authors.initials: PJ
authors.lastname: Joshi
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India.
authors.forename: Akshay D
authors.initials: AD
authors.lastname: Kadam
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India.
authors.forename: Nishant B
authors.initials: NB
authors.lastname: Pande
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India.
authors.forename: Priyanka H
authors.initials: PH
authors.lastname: Kamble
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India.
authors.forename: Shruti P
authors.initials: SP
authors.lastname: Hinge
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India.
authors.forename: Barnali S
authors.initials: BS
authors.lastname: Banerjee
authors.affiliation: Department of Chemical Engineering, AISSMS College of Engineering, Kennedy Road, Pune 411001, India. Electronic address: ashishmohod2004@gmail.com.
authors.forename: Ashish V
authors.initials: AV
authors.lastname: Mohod
authors.affiliation: Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400019, India. Electronic address: pr.gogate@ictmumbai.edu.in.
authors.forename: Parag R
authors.initials: PR
authors.lastname: Gogate
keywords: Intrinsic viscosity; PVP; Polymer degradation; Titanium dioxide; Ultrasound; Ultraviolet irradiation