To start our study, we focused on the two extremes of PBPAC degradation, i.e. no complete conversion and total conversion, so that we could use them as reference points. In cases where no degradation has taken place, this obviously comes back to the study of the raw polymer. We consequently started with the SEC analysis of the latter as it allows for the determination of the molecular weight distribution and by extension the calculation of average molecular weights. In the case of the PBPAC studied, the starting polymer was eluted at 8.5 min in our conditions, with a chain distribution between 7.8 and 10 min (Figure ). The average molar masses of the polymers could be estimated using a polystyrene standard to calibrate the measurement (Figure ), although this is only an estimate as the separation power and retention time in SEC depends on the hydrodynamic volume of the polymer, which can differ between polymers. According to polystyrene (PS) calibration, the Mw of PBPAC was 47000 g•mol -1 , with a Mn of 31000 g•mol -1 , a polydispersity of 1.51 and a molecular weight at the highest point (Mp) of 42000 g•mol -1 . These results are similar to those given by the supplier, with a theoretical Mw of 45000 g•mol -1 . It is important to note that the mass separation profile of the column used is logarithmic, so as mass increases, mass accuracy decreases. Mp measurement uncertainties for the PS standards had error values of 2500 g•mol -1 , 5000 g•mol -1 , 9000 g•mol -1 , 17500 g•mol -1 , 30000 g•mol -1 and 50000 g•mol -1 were measured to be of 59 g•mol -1 , 120 g•mol -1 , 206 g•mol -1 , 375 g•mol -1 , 884 g•mol -1 and 1800 g•mol -1 respectively (Figure ). It is therefore important when interpreting the results to take into account this phenomenon, which obviously depends on the column and elution conditions, and results in variable uncertainty in the absolute measurement of average molar masses. This is why this type of error determination should be carried out and described systematically for each new case study, contrary to what is most often done at present. Tp complement the SEC analysis, the liquid fraction of the prepared polymer suspension was also analyzed in HPLC to detect the potential presence of free BPA monomer, or additional additives, but none could be detected under the analytical conditions used (Figure ). This demonstrates the absence of residual monomer, an important parameter for the study of monomer release in subsequent polymer degradation analysis. Then, to fully characterize the polymer, and more especially its composition (chemical groups) in order to detect any potential subsequent modification, PBPAC was analyzed using three spectroscopic methods, starting with infrared (FT-IR) spectroscopy, the spectrum of which is shown in Figure . The peaks between 3050 cm -1 and 2850 cm -1 correspond to the stretching of the C-H bonds of alkanes and alkenes, while the stretching of the carbonyl of the carbonate function is present at 1777 cm -1 . The peak at 1506 cm -1 is assigned to the stretching of the C=C bonds of aromatic rings. The peaks between 1350 cm -1 and 1100 cm -1 can be assigned to several functions, notably the stretching of the C-O-C bond of the carbonate bond at 1194 cm -1 , as well as a contribution from aromatic ring bonds. Proton NMR spectroscopy provides further support for this identification. The spectrum obtained from the dissolution of our PBPAC sample in CDCl3 is shown in Figure . The constituent monomer is composed of 14 protons, 6 belonging to the methyl groups and 8 to the aromatic rings. The former appears as a singlet at 1.68 ppm, which integrates for 6 protons. Regarding the chemical shift of aromatic hydrogens, it is found between 7.30 and 7.10 ppm, as doublet of doublet with a roofing effect, for which a coupling in J4 can be observed. The first doublet at 7.16 ppm integrates for 4 protons and is attributed to the protons in ortho of the carbonate bond. The second doublet at 7.25 ppm is assigned to the protons in meta of the carbonate group and integrates for 4.2 protons. Considering the overlapping between the latter and the CDCl3 peak (singlet at 7.26 ppm), this may explain the slightly higher integration value than expected. The ortho and meta coupling constants are shown in Figure . These attributions are in line with those proposed by Kim et al. As a result, FT-IR and 1 H NMR here form a complementary pair, allowing the observation of all the chemical functions available i.e. the carbonate bond, the aromatic carbons and the aromatic and methyl protons. NMR analysis of the carbons can be considered to obtain an even finer analysis of the polymer, as proposed by , but this addition is not necessary since carbon's most valuable information is given by infrared. These two methods only allow one to characterize the repeated units of the polymer, present in high concentration, and thus do not give access to the end groups, which are essential elements to be determined with a view to potential degradation of the polymer, particularly with a mechanism in exo. In the case of PBPAC, from the Mn estimated by SEC, it is possible to calculate the concentration of end groups to be close to 0.02 per repeating unit, which is effectively too low to be analyzed by conventional 1 H NMR with the 300 MHz magnetic field. Figure : Fourier transform infrared (FT-IR) spectra of PBPAC, acquisition done in transmission. MALDI-TOF mass spectroscopy provides an answer to this need, by measuring the exact mass of the polymer chains and thus extracting detailed information about the masses of the repeating unit and the ends groups. The MALDI-TOF spectrum obtained with PBPAC is shown in Figure .