Synthesis and properties of new aromatic copolyesters containing phosphorous cyclic bulky groups

Abstract

A series of phosphorus-containing copolyesters was prepared by polycondensation of 2-(6-oxido-6H-dibenz<c,e><1,2>oxaphosphorin-6-yl)-1,4-naphthalene diol, 1, or of an equimolecular amount of 1 and different bisphenols 2, such as 4,4 0 -isopropylidenediphenol, 4,4 0 -(hexafluoroisopropylidene)diphenol and 2,7-dihydroxynaphthalene, with an aromatic diacid chloride containing two preformed ester groups 3, namely, terephthaloyl-bis-(4-oxybenzoyl-chloride). The copolyesters exhibited good thermal stability having the temperature of 5% weight loss above 3808C and char yield at 7008C in the range of 20-31.2%. The glass transition temperature was in the range of 136-1478C. The polymers exhibited thermotropic liquid crystalline behavior, as was observed with polarized optical microscopy, differential scanning calorimetry, and X-ray experiments.

Organometallic Ferrocene- and Phosphorus-Containing Polymers: Synthesis and Characterization

“…Vlad-Bubulac and Hamciuc [225] synthesized a series of phosphorous-containing co-polyesters by polycondensation of an equimolecular amount of 2-(6-oxido-6H-dibenz-1,2-oxaphosphorin-6-yl)-1,4-naphthalene diol, and different bisphenols, such as 4,4 -isopropylidenediphenol, 4,4 -(hexafluoroisopropylidene)diphenol and 2,7-dihydroxynaphthalene, with an aromatic diacid chloride containing two preformed ester groups, namely, terephthaloyl-bis-(4-oxybenzoylchloride). The resulting co-polymers exhibited good thermal stability having a of 5% weight loss temperature above 380°C and char yield at 700°C in the range of 20-31.2%.…”

Preparation and phase behavior of blends of polysulfone‐based polymers with phosphorous‐containing smectic‐A liquid crystals

“…The combination of phosphorus‐containing monomers together with aliphatic moieties and aromatic mesogenic segments have been shown to be the key of achieving flame retardancy, thermal stability, and liquid crystalline properties into the polymeric systems. The use of thermotropic LCC—carefully designed to contain a high content of mesogenic moieties in order to display good mechanical properties and liquid crystalline behavior, a certain amount of aliphatic segments in order to decrease the mesomorphic transitions, and also an optimum phosphorus‐containing bulky groups content in order to feature flame retardancy, good thermal stability, and good solubility—was successfully applied for the control of thermal decomposition, phase transition and crystallinity degree in aromatic‐aliphatic phosphorus‐containing copolyesters [28–31]. In the light of these facts, we considered it would be interesting to prepare and investigate formulations based on such liquid crystalline copolymer and some polymer matrices mainly based on polysulfone or chemically modified polysulfone.…”

“…Previously, we had prepared phosphorus‐containing polysulfones by substitution reaction of chemically modified polysulfone with a phosphorus‐containing compound, namely 9,10‐dihydro‐9‐oxa‐10‐phosphophenanthrene‐10‐oxide (DOPO) [27]. Also, comprehensive studies on the preparation, polymer liquid crystalline phase structure, flame retardancy, and thermo‐oxidative stability of novel thermotropic liquid crystalline aromatic‐aliphatic copolyesters and copoly(ester imide)s based on a new phosphorus‐containing monomers have been performed [28–31].…”

Improved antiplatelet therapy? There's a generic thought

“…The concept of achieving thermal stability, flame retardancy, and liquid crystalline behavior through combination of phosphorus‐containing monomers and aliphatic moieties into aromatic mesogenic moieties was successfully applied for the control of thermal stability, phase transitions, and crystallinity degree of aromatic–aliphatic phosphorus‐containing copolyesters 29, 31–33. Recently, Wang and coworkers have paid attention to the use of phosphorus‐containing TLC polymers for flame retardation on other thermoplastic polymers 34–36.…”