Mousa Sadeghi-Kiakhani1*, Ali Reza Tehrani-Bagha2

Supporting information

for

Enhanced Anti-microbial, Anti-creasing and Dye absorption Properties of Cotton Fabric Treated with Chitosan- Cyanuric Chloride Hybrid

Mousa Sadeghi-Kiakhani1*, Ali Reza Tehrani-Bagha2

1: Institute for Color Science and Technology, Department of Organic Colorants, Tehran-Iran

2: Department of Chemical and Petroleum Engineering, American University of Beirut, Beirut-Lebanon

Corresponding author: Tel: +98 21 22969774; fax: +98 21 22969774; E-mail:

-RSM analysis

RSM as a practical statistical method was used to optimize the process when a combination of several independent variables and their interactions affect desired responses. It tests several variables simultaneously with a minimum number of trials according to individual experimental designs based on factorial designs. The improved process yields, reduced process variability, closer confirmation of the output response to nominal and target requirements, and reduced development time and overall costs could be obtained using statistical experimental design methods. In the present study, a central composite design (CCD) was used to determine the optimum condition for the grafting process of cotton by Ch-Cy. The statistical software “MiniTab” version 16 was applied for central composite design (CCD) and analysis of the obtained data. Four main parameters along with their levels investigated in this study are presented in Table S1.

Table S1. Experimental range and levels of independent process variables

Independent variable / Factor
xi / Range and level
-2 / -1 / 0 / +1 / +2
CCh-Cy% (o.w.f.) / X1 / 10 / 20 / 30 / 40 / 50
Temperature (°C) / X2 / 30 / 40 / 50 / 60 / 70
Time (h) / X3 / 0 / 3 / 6 / 9 / 12
pH / X4 / 2 / 3 / 4 / 5 / 6

- Validation of the model

Analysis of variance (ANOVA)

The statistical importance of the models was justified through the ANOVA for polynomial models with 95 % confidence level, and residual plots were utilized to study the suitability of the models’ fit. The quality of the fit polynomial model was expressed by the coefficient of determination R2. The R2 values provide a measure of how much variability in the observed response values can be explained by the experimental factors and their interactions. At last, the optimal values of the critical parameters were obtained by analyzing surface plots and also by searching a module in dedicated RSM program for a combination of factor levels that satisfy the requirements placed on the response. The ANOVA data for weight gain%are indicated in Table S2. The (P<0.005) implies that the suggested models could be used for fitting the experimental results. The accuracy of the models was further checked by the coefficient of determination R2 values.

Table S2. ANOVA of grafting process of cotton by Ch-Cy

Source / Degree of Freedom (DF) / Sum of Squares (SS) / Mean Square (MS) / FStatistics / P
Model / 14 / 24.080 / 1.720 / 133.56 / 0.000
Linear / 4 / 21.728 / 5.432 / 421.80 / 0.000
Square / 4 / 2.173 / 0.543 / 42.19 / 0.000
Interaction / 6 / 0.179 / 0.029 / 2.33 / 0.083
Residual error / 16 / 0.206 / 0.012
Lack of fit / 10 / 0.201 / 0.201 / 24.13 / 0.000
Pure error / 6 / 0.005 / 0.00083
Total / 30 / 24.286

S = 0.113482, PRESS = 1.16485, R-Sq = 99.15%, R-Sq(pred.) = 95.20%, R-Sq(adj.) = 98.41%

Residual plots

The plots of residuals against fitted values and the normal probability plots for weight gain % are presented in Figure S1. The normality assumption for weight gain% was relatively satisfied as the points in the plot showed a linear trend line. The acceptability of the models fit was also checked by the plots of residuals versus fits and no predominance of positive or negative residuals were found(Figure S1).

Figure S1.Normal probability plot and residual versus fits for grafting process of cotton by Ch-Cy

The effect of operating variables (initial concentration of Ch-Cy, temperature, reaction time and pH) on the grafting process was studied in Figure S2. The optimized conditions were found to be:Concentration of Ch-Cy: 30%o.w.f., temperature: 50 °C, reaction time 3 h, and pH: 4.

Figure S2. Effects of initial concentration of Ch-Cy, temperature, reaction time and pH on the grafting process.

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