Synthesis and characterization of aromatic polyesters and copolyesters from 4,4′-(1-hydroxyphenylidene)diphenol and 4,4′-(9-fluorenylidene)diphenol

Preparation and characterization of new aromatic poly(ether ester)s bearing cardo xanthene groups

A series of new aromatic poly(ether ester)s containing cardo xanthene groups were synthesized by phase transfer–catalyzed interfacial polycondensation of three cardo bisphenols such as 9,9-bis(4-hydroxyphenyl)xanthene, 9,9-bis (4-hydroxy-3-methylphenyl)xanthene, and 9,9-bis(4-hydroxy-3,5-dimethylphenyl)xanthene with terephthaloyl chloride and isophthaloyl chloride. Inherent viscosities and number average molecular weights of the polymers were in the range 0.56–0.80 dL g−1 and 30,300–36,200, respectively. The resulting poly(ether ester)s exhibited high glass transition temperatures ranged from 208°C to 274°C, and their 10% weight loss temperatures were in the range of 440–458°C with char yields above 45% at 600°C under a nitrogen atmosphere. All the poly(ether ester)s were amorphous and readily soluble in organic solvents such as dichloromethane, chloroform, tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidinone at room temperature and could be cast into tough, transparent, and flexible films with tensile strengths of 68.2–86.8 MPa, elongations at break of 2–3%, and tensile moduli of 5.7–7.8 GPa.

Synthesis and characterization of new aromatic polyesters with a (4-phenoxyphenyl)phenylmethene linkage

A series of new aromatic polyesters containing a (4-phenoxyphenyl)phenylmethene linkage were prepared by phase transfer-catalyzed interfacial polycondensation of 1,1-bis(4-hydroxyphenyl)-1-(4-phenoxyphenyl)-1-phenylmethane with terephthaloyl chloride, isophthaloyl chloride, and so on. The inherent viscosities of the polyesters ranged from 0.62 to 0.90 dL/g, while number-average molecular weights were in the range of 30,500–35,500 g/mol. All the polyarylates were readily soluble in organic solvents such as dichloromethane, chloroform (CDCl3), tetrahydrofuran, meta-cresol, pyridine, N, N-dimethylformamide, N, N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature, and could be cast into tough, transparent, and flexible films from their CDCl3 solutions. Wide-angle X-ray diffraction measurements revealed the amorphous nature of the polyarylates. These polymers showed glass transition temperatures ( Tgs) between 178°C and 240°C and decomposition temperatures at 10% weight loss ranging from 446°C to 483°C, while the initial degradation temperatures in the range of 410–435°C under nitrogen atmosphere. These new polyarylates exhibited higher Tgs and better solubility than bisphenol A-based analogues.

Synthesis and characterization of new aliphatic polyesters containing dihydronaphthofuro[3,2-d]furan moiety

A dihydronaphthofuro[3,2-d]furan containing diol monomer, viz., 2,13-dihydroxy[7a,14c] dihydro naphtho[2,1-b]naphtho[1′,2′:4,5]furo[3,2-d] furan (DDNF) was synthesized in high yield and purity through the condensation of commercially available 2,7-dihydroxynaphthalene with glyoxal at room temperature. It was used as a new monomer for the synthesis of a series of novel dihydronaphthofuro-containing aliphatic polyesters by interfacial polycondensation method. Optimal conditions for polyesterification were obtained via study of the model compounds. The diol monomer and model compound were fully characterized by infrared, nuclear magnetic resonance (NMR), mass spectroscopies, and elemental analysis. Polyesters derived from DDNF and four aliphatic diacid chlorides had inherent viscosities ranging from 0.36 to 0.51 dL g−1. The chemical structure of the polymers was characterized by Fourier transform infrared, NMR spectroscopies and elemental analysis. The physical properties of the polymers were studied. The glass transition temperature was in the range of 89–118 °C. All the new polymers showed good thermal stability and very good solubility in most organic solvents.

Synthesis and Characterization of Isophthalic Polyesters and Copolyesters based on 2,4-Dihydroxybenzophenone and 4,4’-(hexafluoroisopropylidene)diphenol

Two aromatic isophthalic polyesters and three copolyesters were synthesized by interfacial polycondensation using 2,4-dihydroxybenzophenone (2,4-DBP) and 4,4'-(hexafluoroisopropylidene)diphenol (HFD) with isophthaloyl chloride (ISO). All polymers were soluble in common chlorinated solvents. These aromatic polyesters and copolyesters were characterized by infrared and nuclear magnetic resonance spectroscopy. Their thermal, dynamic mechanical and physical properties were also determined. The glass transition temperature, onset of decomposition, and thermal stability of the homopolymer, poly(hexafluoroisopropilydene)isophthalate (HFD/ISO), were higher than those of homopolymer poly(2,4-benzophenone)isophthalate (2,4-DBP/ISO). The thermal properties of the copolyesters HFD/ ISO-co-DBP/ISO depend upon the amounts of HFD/ISO moiety present in the copolymer. Physical properties of the copolyesters were intermediate between those of the homopolyesters and depend upon the concentration of comonomers present in the copolyester.