The aim of this research was to attach hydrophobic amino acids to the surfa
ce of cashmere in an attempt to improve the water repellency without affect
ing its inherent properties. Two separate enzyme modification processes are
described for peptide bond formation. To detect improvements in water repe
llency, new methods were developed for measuring hydrophobicity on fiber su
rfaces, concentrating particularly on the reproducibility of such measureme
nt. The amino acid grafting demonstration provided the groundwork for fiber
improvements by the attachment of other amino acids.