Synthesis and characterization of α‐hydroxy, α‐thiol and α‐chloroformyl oligomers of poly(butylene terephthalate)

Abstract

α‐Hydroxy and α‐chloroformyl oligomers of poly(butylene terephthalate) (PBT) were prepared in 1,1,2,2‐tetrachloroethane by condensing terephthaloyl chloride and 1,4‐butanediol and using benzoyl chloride and 4‐hydroxybutyl benzoate as chain limitator. The average molecular weight was determined by 1H NMR analysis, and thermal properties were assessed by differential scanning calorimetry (DSC). Preparation of α‐thiol oligomers of PBT was also investigated by esterification of α‐hydroxy oligomers with thioglycolic acid and using p‐toluenesulfonic acid as catalyst. The DSC and TGA analyses pointed out that the introduction of a thiol group by esterification has no influence on the thermal properties of the PBT oligomers.

End-Groups-Dependent MALDI Spectra of Polymer Mixtures

“…The concentration of end groups of the studied telechelic polymers, reported in Table 1, was carefully characterized using appropriate methods reported in the literature. [11][12][13] The content of carboxyl groups in the Ny6 samples was determined by conductometric titration in trifluoroethanol (TFE) with a acqueous solution of sodium hydroxide (NaOH), 0.05 N. 11 The amount of acid end groups in the PBT samples was determined by potentiometric titration. 12 Typically, 2 g of a PBT sample was dissolved in 100 mL of o-cresol at 90°, in a nitrogen atmosphere.…”

“…The concentrations of hydroxyl (OH) end groups in the PBT samples were determined by 1 H NMR analysis in deuterated tetrachlotoethane, at room temperature, 13 using the area of the signals at 4.38 and 3.67 ppm corresponding to the methylene groups linked to ester groups and methylene groups in R-position to OH, respectively.…”

Synthesis and characterization of triblock copolymer PLA-b-PBT-b-PLA and its effect on the crystallization of PLA

“…Note that the hydroxyl proton resonance of the chain end was overlapped by the proton of the TFA-1 d solvent used in this 1 H NMR test and thus could not be identified. According to the previous work, 28,29 the M nNMR of the PBT was calculated from the corresponding integrals of -OC-C 6 H 4 -CO-phenyl proton signals (I 4 in Fig. 1) at 7.92 ppm and the chain-end methylene proton of HOCH 2 CH 2 signals (I 1 in Fig.…”

Dixanthate-terminated poly(butylene terephthalate). A novel RAFT/MADIX agent for the synthesis of well-defined triblock copolymers resulting from consecutive step- and chain-growth polymerization processes

“…General procedure for the synthesis of xanthate-terminated poly (butylene terephthalate) RAFT/MADIX agent Method A -Step-growth polymerization following by end-group transformation reactions. Synthesis of dihydroxy-terminated poly (butylene terephthalate) (1) PBT 1 was prepared following a modified protocol from Boutevin et al 46 1,4-Butanediol (7.90 g, 87.8 mmol) and pyridine (8.40 g, 106.3 mmol) were simultaneously added under argon to a solution of terephthaloyl chloride (15.03 g, 74.1 mmol) in 1,1,2,2-TCE (120 mL) at room temperature in a 250 mL threeneck round-bottom flask equipped with a magnetic stirrer and a reflux condenser. The reaction mixture was heated under argon at 110 C for 6 h. The solution was then cooled to ambient temperature.…”