A series of poly(urethane)s (PUs) based on diphenyl-silane or -germane and oxyphenyl units were synthesized by polycondesation of 4-[4-[9-[4-(4-aminophenoxy)-3-methyl-phenyl]fluoren-9-yl]-2-methyl-phenoxy]aniline (3) and four bis(chloroformate)s (I-IV). These monomers were prepared and characterized in previous works. The best conditions for the polymerization reactions were investigated by a kinetic study. Also, a selection of the best solvent for the reaction was developed. Polymers were characterized by IR and 1 H, C range by DSC analysis. Thermal decomposition temperature (TDT 10% ) values were above 300 C. All PUs showed good transparency in the visible region (>80% at 350 nm) due to the incorporation of the bulky monomer (fluorene) and oxyether linkages.
Poly(ether-amide)s derived from two new silylated-dianhydrides were prepared and characterized. By FE-SEM and AFM morphological studies were developed.
Polyamides (PAs) containing fluorene, oxyether, and diphenyl-silane moieties in the repeating unit were synthesized in > 85% yield by direct polycondesation between a diamine and four dicarboxylic acids. Alternatively, one PA was synthesized from an acid dichloride. The diamine 4-[4-[9-[4-(4-aminophenoxy)-3-methyl-phenyl]fluoren-9-yl]-2-methyl-phenoxy]aniline (3) was obtained from the corresponding dinitro compound, which was synthesized by nucleophilic aromatic halogen displacement from p-chloronitrobenzene and 9,9-bis (4-hydroxy-3-methyl-phenyl)fluorene (1). Monomers and polymers were characterized by FTIR and C range by DSC analysis. Thermal decomposition temperature (TDT 10% ) values were above 400 C due to the presence of the aromatic rings in the diamine. All PAs showed good transparency in the visible region (>88% at 400 nm) due to the incorporation of the fluorene moiety.
Oligomeric poly(amide)s (PAs) were synthesized from monomeric diacids, which were obtained from phthalic anhydride and the amino acid glycine, L-alanine, L-phenylalanine, L-valine, L-leucine, L-isoleucine and p-aminobenzoic acid. The phthalimidyl acids (IA-1 to IA-7) reacted with 5-amino-isophthalic acid in order to obtain the monomeric diacids (1-7). Furthermore, the monomeric diacid 8 was obtained by direct reaction between phthalic anhydride and 5-aminoisophthalic acid. The isophthalic acid derivatives were reacted with bis(4-aminophenyl)diphenylsilane in order to obtain the PAs. Monomers and polymers were characterized by infrared and 1 H-, 13 C-and 29 Si-NMR spectroscopy, elemental analysis and, when necessary, optical rotation. The results were in agreement with the proposed structures. The yields were generally good, but the inh values were low, indicating that the polymers were of oligomeric nature, namely, a chain of moderate molecular weight. The polymers were soluble in polar aprotic solvents and some of them were soluble in mcresol and tetrahydrofuran. The glass transition temperatures (T g ) values were obtained by differential scanning calorimetry, showing, in general, a decrease in value when the volume of the side chain of the amino acid moiety was increased. The thermal stability of the polymers was determined by dynamic thermogravimetry, showing good values of thermal decomposition temperatures (TDT), especially for those with aromatic residue in the amino acid, and for PA without amino acid. For PAs in which the side chain of the amino acid was larger, the TDT values were lower, probably due to the lack of symmetry and the length of the side chain, both of which have influence on the thermal stability.
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