Synthesis of aromatic polyesters having pendant carboxyl groups in the side chains and conversion of the carboxyl groups to other reactive groups

Abstract

Aromatic polyester, copolyester, and poly(ester‐amide‐thioester) having pendant carboxyl groups are directly synthesized by the organic phase/water phase interfacial polyconden‐sation using low‐molecular and polymeric phase transfer catalysts. Spectral analysis of the resulting polymers indicates that the nucleophilicity of salts of phenols to diacid chloride is far higher than that of salts of carboxylic acids and chemoselective esterification occurs in a 100% yield. Even if the polymeric catalyst having amino acid moiety as a nucleophilic group is used in the polycondensation, the polymers do not contain anhydride groups. The polyester can be almost quantitatively converted to polymers with different reactive groups by reacting the pendant carboxyl groups with alkyl halides in a DMAc‐H2O mixture con‐taining K2CO3. A bifunctional catalytic mechanism is proposed for the chemical modification of the polyesters. © 1995 John Wiley & Sons, Inc.

Interfacial polycondensation of diphenolic acid and isophthaloyl chloride

“…The intrinsic viscosity [η] of poly(DPA‐IPC) was measured with a Ubbelodhe viscometer at 30°C using a 0.5 g/dL poly(DPA‐IPC) solution in tetrachloroethane/phenol mixture solvent (2 : 3 by weight) containing 4.8% (by volume) of H 2 SO 4 4…”

“…It has been reported that poly(DPA‐IPC) can be synthesized via interfacial polycondensation of DPA and isophthaloyl chloride (IPC) catalyzed by quaternary ammonium salts,4, 6 crown ethers,6 and polymeric catalyst4, 5 in various solvent/water systems, but the yield and the molecular weight of the produced polymer were relatively lower. It seems that there are big spaces to optimize the polymerization process.…”

“…3 It has been used as a new monomer in preparation of reactive aromatic polyesters 4-6 and polycarbonates 7,8 bearing pendent carboxyl groups via interfacial polycondensation as well as hyperbranched polyesters via melt polycondensation. 9 As the carboxyl groups can be converted into other useful groups, 4 these polymers are expected for application as polymer catalyst, amphiphilic polyelectrolytes, chelating agents for metal ions, and drug delivery carriers. 6 It has been reported that poly(DPA-IPC) can be synthesized via interfacial polycondensation of DPA and isophthaloyl chloride (IPC) catalyzed by quaternary ammonium salts, 4,6 crown ethers, 6 and polymeric catalyst 4,5 in various solvent/water systems, but the yield and the molecular weight of the produced polymer were relatively lower.…”

Preparation and characterization of the soluble NLO polyarylates with enhanced electro-optic properties

“…The mixture was stirred at room temperature for 2 h. After that, the acetone was removed by rotary evaporator, and the rest part was extracted by acetic ether. After dried, the cru Synthesis of the Polymers sPAR: Polycondensation was carried out in an aqueous/organic two phase system, using tetrabutyl ammonium bromide as the phase transfer catalyst [17][18][19]. Isophthaloyl dichloride (4.06 g, 20 mmol) in 50 mL of dichloroethane was added to 5.72 g (20 mmol) of diphenolicacid in 100 ml of aqueous NaOH solution (including 30 mmol NaOH) in the presence of 0.1 g of tetrabutyl ammonium bromide.…”

Design, Synthesis, and Application of Novel Flame Retardants Derived From Biomass

“…As one of the derivatives from levulinic acid, diphenolic acid (DPA, with the chemical name of 4,4-bis-(4'-hydroxyphenyl) pentanoic acid) has been deemed a new monomer in the preparation of reactive aromatic polyesters and polycarbonates due to its multifunctional groups (Wang and Nakamura 1995;Zhang and Moore 2002;Zhang and Moore 2003). However, little attention has been paid to their potential use as flame retardants.…”