Presenter: Carrie E. Cornelius
Advisor(s): Mohamed A. Bourham
Author(s): Carrie E. Cornelius, Marian G. McCord and Mohamed A. Bourham
Graduate Program:
Nuclear Engineering, Textile Engineering, Nuclear Engineering

Title: Efficacy of Chemical Spray Application on Atmospheric Pressure Plasma Treated Cellulosic Paper

Abstract: Plasma aided grafting of 100% cellulosic paper was investigated using atmospheric pressure plasma generated at audio frequency 4-12 kHz. Atmospheric pressure plasma is generated by a dielectric barrier discharge operating at 4.8kW audio frequency power supply. Grafting active chemicals onto cellulosic papers was conducted using spraying technique either prior or post plasma exposure. The active exposure area inside the discharge is ~ 60 x 60 cm between two copper electrodes embedded in Lexan insulators to act as dielectric barrier discharge, with a fixed 5 cm electrode separation.  Helium gas is used as the seed gas to initiate the discharge and is injected between the electrodes into a test cell at a constant flow rate of 10L/m.  Oxygen was introduced into the helium flow at a ratio of 1%. Oxygen is used as the surface activation plasma gas, which allows for scission of the cellulose chain to induce cross-linking of antimicrobial agents. The discharge has typical parameters of 1-2eV electron plasma temperature and an electron number density of 1E14 - 1E16 /m^3.

Before and/or after treatment in the plasma the samples were grafted with active antimicrobial agents, specifically beta-cyclodextrin or chitosan.  Glycidyl Methacrylate, often used as a linker to attach the chitosan or Beta-cyclodextrin to the polymer chain of the fibers, was also grafted followed by subsequent grafting of the active agents. Exposure to plasma was limited to two minutes.

The percent add-on of active agents was determined by the weight change after preliminary washing. The % add-on of Glycidyl Methacrylate varies between 4.88 to 6.31%. For other active agents, the % add-on varies between 3.66 to 10.19%. Scanning Electron Microscopy (SEM) showed evidence of grafted agents.  Fourier Transform Infrared Spectroscopy (FTIR) showed the typical peaks of grafted active agents.