Optimization of Environmentally Benign Polymers Based on Thymine and Polyvinyl Sulfonate Using Plackett-Burman Design and Surface Response
Table 4
Effects of the variables and statistical analysis of the PBD.
Source
Coefficient estimatea
Sum of squares
dfb
Mean square
value
value
Prob >
Model
0.4215968
7
0.06022811
13.1201459
0.0128
A
−0.0630
0.03967072
1
0.03967072
8.64190442
0.0424
B
0.079
0.06239922
1
0.06239922
13.593102
0.0211
C
−0.02242
0.00503972
1
0.00503972
1.09785677
0.3539
D
−0.0058
0.00034116
1
0.00034116
0.07431762
0.7986
E
0.0600
0.03602371
1
0.03602371
7.84743665
0.0487
F
0.0368
0.01359198
1
0.01359198
2.96088871
0.1604
G
−0.1287
0.1657404
1
0.1657404
36.1050351
0.0039
Residual
0.01836203
4
0.00459051
Lack of fit
0.01812003
3
0.00604001
24.9587134
0.1458
Pure error
0.000242
1
0.000242
Cor Totalc
0.43995883
11
aIn terms of coded factors. For the intercept, the estimated coefficient is 0.39. bDegree of freedom. cSum of total squares corrected for the mean. The significant factors (at 5% significance level) are shown in bold type.