Attempt to control monomer sequences in copolycondensations of IPA, TPA, BPA, and PHB

Modification of polycondensation of isophthalic and terephthalic acids and bisphenols with tosyl chloride/dimethylformamide/pyridine by the presence of additives

“…Because similarly electron‐donating alkylidene groups at the p position in BPs may not influence the acidities of two hydroxyl groups, the results could not be explained by the reactivity of BPs. The preformed IPA/TPA‐BPP (50 mol %) oligomers contained about 60 wt % of the oligomers of more than about 900 of molecular weight 3. They might associate with each other by the dipole–dipole interactions between their ester moieties and by hydrophobic ones between the BPP moieties.…”

“…According to our previous research,3–7 a mixture of TsCl (13 mmol) and DMF (10 mmol) in Py (5 mL), prepared and aged at room temperature for 30 min, was reacted with a Py (10 mL) solution of equal parts (2.5 mmol) of IPA and TPA at room temperature for 10 min and then at 80 °C (bath temperature) for 10 min. To the resulting mixture, BPP (2.5 mmol) in Py (10 mL) was added all at once, and the solution was kept at 80 °C for 30 min.…”

“…The oligomer distribution was determined with two polystyrene gels columns (8 × 300 mm) in series having exclusion limits of 4.0 × 10 5 and 2 × 10 4 with chloroform as an eluent at a flow rate of 1 mL/min. Peaks due to x ‐mers ( x = 0–4) were assigned according to our previous research 3, 6…”

Preparation of Polyarylates from Dihydroxyaceto-phenones by the Solution Polycondensation with TsCl/DMF/Py as a Condensing Agent

“…41.5, 38.7, 37.2, 36.3, and 35.4, which are very close to those in the oligomers prepared from BPA and phenylhydroquinone, and were assigned to n = 0, 1, 2, 3, and 4 in the IPA/TPA-(DHAPs-IPA/TPA) n oligomers, respectively, according to the BPA oligomers in our previous works. [3,6] …”

High-viscosity polyesters from secondary alicyclic 1,4-cyclohexanedicarboxylic acids and hydroquinones with thionyl chloride/pyridine condensing agent

“…The melting point (T m ) was determined by microscopic observation on a modified melting point apparatus (Yazawa BY-2, Tokyo Japan) equipped with two polarizing films. [10] …”