Rot Resistance and Biocidal Activity of Halodeoxycellulose Fabrics

Chlorodeoxycellulose in fabric form was prepared by reacting cotton printcloth with chlorodimethylformiminium chloride (DMFCl₂) in DMF at 65-75°C. Iododeoxycellulose fabric was prepared by treating printcloth at 25°C with either thionyl chloride or DMFCl₂ in DMF and subsequently reacting the fabric with KI in DMF at 90-125°C. The treated fabrics were examined for rot resistance and biocidal activity. Chlorodeoxycellulose fabrics were relatively unaffected after 4 weeks soil burial, and fabrics having a chlorine content of 4% or greater retained 20% of their tensile strength after 12 weeks burial, thus exhibiting a relatively high degree of rot resistance. Iododeoxycellulose fabrics prepared by the DMFCl₂ methods retained over half their strength after 8 weeks soil burial. Fabrics treated to a similar level of iodination (5-5.4% I) by the thionyl chloride—KI method retained only 5% of their strength after a comparable period of soil burial. The biocidal activity of the halodeoxycellulose fabrics, as measured by the parallel streak test, was highest for chlorodeoxycellulose containing 4.5% or more of chlorine. Iododeoxycellulose fabrics of comparable halogen content possessed only moderate antibacterial activity.