Synthesis and properties of novel soluble fluorinated polyamides containing pyridine and sulfone moieties

Synthesis and thermal, optical and morphological characterization of oligomeric polyamides based on thiophene and alkyl/phenyl‐silane moieties. Study of the electrospun deposition process

“…Some strategies to improve processing properties of aromatic PAs includes the introduction of specific substituents on the aromatic rings, e.g., bulky substructures or side groups, which favors the separation of the polymer chains and hinder molecular packing or crystallization . In further details, the incorporation of fluorine as trifluoromethyl groups reduces interchain interaction and increases the material optical clarity; linear aliphatic and nonlinear rigid alicyclic/aromatic structures or asymmetric monomer could affect the molecular ordering in the system . The introduction of flexible moieties, such as diamines, diacids and silane groups, into the polymer backbone should reduce the chain stiffness, increasing the solubility and decreasing the glass transition temperature without sacrificing the final thermal stability of the material …”

Fluorinated Polyamides

“…Liu et al synthesized a new diamine containing pyridine moiety and -CF 3 groups, 4-(4-trifluoromethylphenyl)-2,6-bis(4-aminophenyl)pyridine, and used it for the preparation of PAs containing sulfone moieties (Figure 4.25) [23]. Liu et al synthesized a new diamine containing pyridine moiety and -CF 3 groups, 4-(4-trifluoromethylphenyl)-2,6-bis(4-aminophenyl)pyridine, and used it for the preparation of PAs containing sulfone moieties (Figure 4.25) [23].…”

“…This is attributed to their decomposition temperature being below their melt temperature [1]. It is reported in the literature that the presence of bulky hexafluoroisopropylidene [-C(CF 3 ) 2 ] or trifluoromethyl (-CF 3 ) groups in the polyamide structure endows remarkable improvements in several properties compared to nonfluorinated polyamides [12][13][14][15][16][17][18][19][20][21][22][23][24][25]. The solubility of a less rigid and less linear structure like PMPI is higher due to the concomitant reduction in cohesive energy and crystallization tendency compared to PPPT.…”

“…25 Sulfonated fluorinated polyamides containing pyridine moiety[23].The higher optical transparency of these polymers is attributed to the presence of the pendant 4-trifluoromethylphenyl substituents in the polymer backbone. The dielectric constant values were measured by the parallel plate capacitor method using a dielectric analyzer.…”

Synthesis and properties of novel soluble polyamides containing both fluorene or xanthene cardo moieties and fluorinated phenoxy pendant groups

“…The incorporation of fluorine substituents and bulky pendant groups into the polymers is considered as effective ways to obtain a low dielectric constant property. In recent years, the introduction of fluorine into the polyamide backbones has been intensively explored because of the unique characteristics of fluorine substituents . Fluorine incorporation has been found to generally decrease the dielectric constant and moisture absorption, to improve the optical properties, and also to increase the thermal stability.…”