Low temperature synthesis of a self-assembling composite: hydroxyapatite-poly[bis(sodium carboxylatophenoxy)phosphazene]

Expanding Options in Polyphosphazene Biomedical Research

“…The number of cross-links, and therefore the degree of water swelling, is controlled by the length of radiation exposure time. A second method requires the introduction of a carboxylic acid substituent function (structure 22) or the two substituents shown in structure 23 [69][70][71][72][73][74][75][76][77][78][79]. The presence of the carboxylic acidic function in 22 or 23 means that hydrogels expand in basic media (e.g., dilute sodium hydroxide) but contract in acidic media, due to the charge repulsion between the protons in solution and the protonated carboxylic acid groups.…”

Low temperature formation of hydroxyapatite-poly(alkyl oxybenzoate)phosphazene composites for biomedical applications

“…The general synthesis route to polyphosphazenes involves macromolecular substitution reactions on poly(dichlorophosphazene), resulting in polymers with different functionalities, and consequently different properties [26]. Polyphosphazenebased polymers have been reported to form composites with HAp [27][28][29]. TenHuisen et al [27] and Greish et al [28] studied the formation of a composite comprised of CDHAp and poly(bis(sodium carboxylatophenoxy)phosphazene) (Na-PCPP).…”

“…Polyphosphazenebased polymers have been reported to form composites with HAp [27][28][29]. TenHuisen et al [27] and Greish et al [28] studied the formation of a composite comprised of CDHAp and poly(bis(sodium carboxylatophenoxy)phosphazene) (Na-PCPP). During composite formation, an exchange reaction took place when sodium ions from the polymer were replaced by calcium ions from the calcium phosphate precursors, resulting in the formation of a calcium cross-linked polymer (Ca-PCPP) and a CDHAp [28].…”

Hydrolysis of tetracalcium phosphate in the presence of a poly(alkenoic acid)

“…For example, TenHusein et al 7 observed that acidic polyphosphazines will react in this way. For example, TenHusein et al 7 observed that acidic polyphosphazines will react in this way.…”