## 3 Results and Discussion  
The mechanical properties, water vapor permeability, optical properties, antimicrobial activity and biodegradability of these films have been analyzed in a previous study [25]. Table 3 presents the range of the thickness of the films that were tested in the present study. As Table 2 and Figure 2 indicate, 11 elongation levels were used in the analysis, but, for reasons of expediency, 4 groups were chosen based on the ranges extended by the 3 mode frequencies of the exactly broken units per level, leaving only the level 5%: 8-14%, 15-20% and  
Both variables of the destructive degradation process were logarithmized to produce a better linear fit (b = 0.244, determined R\({}^{2}\) = 0.485, \(p\) < 0.001), expressing a decline of the log tensile quotient as the log exact break time increased (Figure 3). Four regression lines were also embedded in the graph after separating the data in the four elongation groups. By consulting the regression slopes, it was deduced that the log tensile quotient declined more abruptly as the elongation groups decreased in size range. This decrease was particularly observed in the first two ranges (8-14% and 15-20%), whose 95% confidence intervals did not overlap with the other groups. It is worth mentioning the doubly steep descent of the reference elongation level 5% (b = 0.536) as compared to the highest ranges and the significant delayed time that elapsed until the first units commenced breaking (greater than 54.6 s, corresponding to antilog(4)), which is understandable due to the low stress intensity and the significant contribution of the break cycle. More specifically, it can be observed in Figure 3 that there were very few ruptured films at low log exact break time values and low break cycles related to the elongation group 5%. Most of the destructed films at this elongation group existed at high break cycles and high log exact break times, which dragged the model line to a steeper trend. Generally, the stress levels that starch biodegradable films are subjected to should be at low levels, as is highlighted in other studies [30,31]. As the log exact break time increased, the level of break cycle also increased, reaching maxima approximately in the area confined by 5-9 log times and lower than 1 log tensile quotient, which means that the high-cycle force at levels within the elastic deformation caused a lesser degradation effect to the films than the intense low-cycle force and, eventually, increased the biodegradable starch film shelf life [32]. When the sample ID variable is involved in the analysis, some interesting observations are noted (Figure 4). More specifically, the sample 7_35_10.5 showed the most versatile capabilities, expanding over the whole range of the log tensile quotient, and was the treatment that had the most films that survived to the higher log tensile quotient values and higher log exact break time intervals compared to the other treatments. Moreover, it can be seen from Figure 5--which is an alternative version of the previous findings where the 95% confidence intervals per sample are deployed over the increasing range scale of log exact break time--that at all log exact break time intervals, the treatment 7_35_10.5 had the highest log tensile quotient. This treatment had a higher percentage of nanoclay and starch and the lowest percentage of  
Figure 2: Frequency distribution of the experimental units based on the elongation level (%). glycerol. On the contrary, the samples 4_50_1 and 7_50_1 achieved the lowest log tensile quotients at all log exact break time intervals (Figure 5). Finally, the sample 7_50_10.5 exhibited the lowest expanding range over the log tensile quotient (Figure 4), thus showing the least response of potential effects and thereby being the least acceptable. These two treatments had the highest glycerol and nanoclay concentration, and the higher glycerol and lowest nanoclay concentration, respectively.