Table 4.

The effect of humidity on the stability of CIL in pure and CIL co-formulated with PVP at 90 °C

T = 363 K – influence of air relative humidity on CIL decomposition
	Pure CIL (6)	CIL/PVP solid dispersion	CIL/PVP physical mixture
RH%		k ± ∆k [1/s]
25.0 %	(3.270 ± 0.241) 10-6	(9.460 ± 0.822) 10-7	(9.010 ± 0.664) 10-7
50.9 %	(7.922 ± 0.964) 10-6	(1.522 ± 0.514) 10-6	(1.555 ± 0.419) 10-6
60.5 %	(1.189 ± 0.068) 10-5	(1.999 ± 0.168) 10-6	(2.079 ± 0.281) 10-6
66.5 %	(1.583 ± 0.143) 10-5	(2.883 ± 0.467) 10-6	(2.32 3 ± 0.415) 10-6
76.4 %	(1.941 ± 0.106) 10-5	(3.041 ± 0.143) 10-6	(3.010 ± 0.331) 10-6
linear relationship lnk = f(RH)
a	0.036 ± 0.006	0.024 ± 0.009	0.023 ± 0.002
sa	0.002	0.002	0.0008
b	-13.526 ± 0.23	-14.510 ± 0.57	-14.520 ± 0.15
sb	0.102	0.181	0.481
r	0.997	0.976	0.998

The parameters: a, Sa, b, Sb and r were calculated by least square regression and are standing for slope, standard deviation of the slope, intercept, standard deviation of intercept and correlation coefficient, respectively.