Optimization of PET Glycolysis Process by Response Surface Methodological Approach: A Two-Component Modelling Using Glycolysis Time and Temperature

Table 2

Coefficients of fitted equations and their percent significance 𝑌=𝑎₀+𝑎₁𝑥₁+𝑎₂𝑥₂+𝑎₃𝑥₁𝑥₂+𝑎₄𝑥₁₂+𝑎₅𝑥₂₂.

S. no.	Property	𝑎0	𝑎1	𝑎2	𝑎3	𝑎4	𝑎5	𝐹-ratio	% Fit
1	Hydroxyl value	37.54	2.58	1.36	−0.30	−1.96	−0.50	8.96	86.4
2	Acid value	15.40	−0.43	−0.11	−0.65	−0.47	−1.42	38.52	96.4
3	Av. mol. wt	700.00	−181.76	139.52	66.50	171.31	76.56	8.04	85.1
4	Glycolysis conversion %	95.00	28.15	12.53	11.25	−19.50	25.25	342.88	99.5