Synthesis and characterization of aromatic copolyesters derived from bisphenol B and phenol red

Abstract

A series of novel aromatic copolyesters derived from bisphenol B (BPB) and phenol red (PR) were synthesized by interfacial polymerization. The number‐ and weight‐average molecular weight (Mn and Mw) of the obtained amorphous aromatic copolyesters ranged from 1.06–1.80 × 104 to 2.01–6.17 × 104 g/mol, respectively. Density functional theory calculations showed that the reactivity of BPB was similar to that of bisphenol A. The reaction activation energy of BPB with terephthaloyl and isophthaloyl chloride (TPC and IPC) was 8.23 kcal/mol, and PR with IPC and TPC was 59.30 kcal/mol. Under the influence of the ethyl side group of BPB and the pendant group of PR, the solubility of the aromatic copolymer was improved, and the glass transition temperature (Tg) was 125.1–195.3°C, while Tmax could still be maintained above 525.72°C. The optical transmittance of the copolyesters at 450 nm (T450) was 69.29%–99.41%, and the tensile strength and Young's modulus were in the range of 46.79–58.59 MPa and 1.39–1.86 GPa respectively. All aromatic copolyesters exhibit good mechanical and processability properties and have great application potential as high‐performance plastics.

Synthesis and properties of novel block-structured polyarylates containing fluorene: a two-step interface polymerization

“…35 Conversely, the T g of the polyarylate appeared to decrease with an increase in IPC content. 29 Furthermore, the T g of block polyarylates was higher than that of random polyarylates. This is due to the fact that the synthesis of block polymers is divided into two steps: in the first polymerization step, the bisphenol A molecule is synthesised with longer chain segments, and in the second polymerization step, the short BHPF chain segments are joined to the long BPA chain segments to form a ‘block’ to ‘block’ connection.…”

“…The BHPF content (φBHPF) in the polymers was calculated by the 1 H NMR spectra using the integrated areas ( S 7 , S 13 ), which are shown in Table 3. 29…”

“…The solvent was allowed to volatilise naturally by placing it horizontally for 24 hours at room temperature to obtain a homogeneous, transparent and tough film. 29 The resulting film is shown in Fig. 3.…”