## 3 Results and Discussion  
### Characterization of Flax Yarns After Enzymatic Treatment  
In the initial phase of the work, enzymatic treatments were carried out only on flax fabrics. For both Feedlyve and Peclyve preparations, the fabrics were treated using an enzyme load of 0.5, 2.5 and 5 wt % and a duration of 2, 3 and 6 h. The aim of this phase of the study was to verify the actual effect of the two enzymatic preparations on the surface properties of flax and thus to select the solution able to produce the best results. Enzymes are able to modify surface properties without significantly affecting bulk properties [34]. It was supposed that the removal of hemicellulose and pectin from the flax fibres would reduce their hydrophilic behaviour, making them more resistant to moisture andthermally stable. In this framework, the wetting properties of the untreated and treated flax fabrics were analysed by a water drop test. Representative values of the absorption times are reported in Table 2. Due to the presence of hydroxyl and strongly polar groups, the untreated flax fabrics showed a marked hydrophilic behaviour. Water retention times lower than 1 s were found for the as-received flax fabric. From the results reported in Table 2, it is possible to notice that flax fabrics displayed a wetting behaviour strongly dependent on the type of enzymatic preparation used. An increase in the hydrophobic behaviour was produced after the application of Peclyve. In contrast, the flax fabrics treated with Feedlyve maintained their strong hydrophilic behaviour. Figure 1 compares the time sequences of the water drop tests carried out for fabrics treated using Feedlyve and Peclyve at 5 wt % for a duration of 6 h. A maximum value of water retention time of 50 s was obtained after the treatment with Peclyve. In contrast, the flax fabric treated by the Feedlyve showed a water retention time of lower than 1 s. According to [PERSON] et al. [21], the increase in hydrophobic behaviour may be explained by the removal of pectin and hemicellulose fractions on the fibres' surface produced by pectinase and xyloglucanase. The better results obtained by Peclyve can be attributed to the synergic action of pectinase and xyloglucanase. In contrast, the presence of only endo 1,4-\(\beta\)-xylanase in Feedlyve was not able to induce substantial modifications of the flax properties. [PERSON] et al. [25; 35] investigated different enzyme combinations based on several pectinase and hemicellulose activities, including up to three different enzymes applied to flax fibres, and discussed their effects on the chemical fibre composition, ease of fibre extraction and fibre fineness. They identified some synergic combinations that resulted in enhanced cellulose content (polygalacturonase + xylanase), while combinations with three enzymes showed significant improvements in fibre fineness compared to the single enzyme treatments. It was hypothesized \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Fax Fabric**} & **Absorption** & **Absorption Time t** & **Absorption Time t** & **Absorption Time t** \\  & **Time t [s]** & **after 2 h** & **after 3 h** & **after 6 h** \\  & & **Treatment [s]** & **Treatment [s]** & **Treatment [s]** \\ \hline Neat & T \(<\) 1 & - & - & - \\ Peclyve 0.5 wt \% & - & 1 & 1.2 & 5.5 \\ Peclyve 2.5 wt \% & - & 1.4 & 2.2 & 1.5 \\ Peclyve 5 wt \% & - & 1.5 & 35 & 50 \\ Feedlyve 0.5 wt \% & - & t \(<\) 2 & t \(<\) 1 & 1 \\ Feedlyve 2.5 wt \% & - & t \(<\) 2 & 1 & t \(<\) 1 \\ Feedlyve 5 wt \% & - & 1 & t \(<\) 1 & t \(<\) 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Water absorption time values obtained for the untreated and enzymatically treated flax fabric surface. Figure 1: Representative time sequences of the water drop test performed on the flax fabrics treated with Feedlyve and Peclyve at 5 wt % for 6 h.  
that when pectinases and hemicelllualases are combined, the polymer network surrounding the fibre should be degraded more efficiently.