Crosslinkable Citronellol Containing Polyphosphazenes and Their Biomedical Potential

An increased focus exists on the development of materials that might serve as ligament or tendon tissue engineering scaffolds. Requirements for a suitable candidate polymer include biodegradability, biocompatibility, and elasticity. In an attempt to meet these requirements novel citronellol-containing polyphosphazenes were synthesized, characterized, and crosslinked to generate elastomers. Citronellol was chosen as a side group due to its anti-inflammatory properties in addition to the presence of a double bond in its structure to permit polymer crosslinking. Alanine ethyl ester was chosen as a co-substituent to tune hydrolysis rates without severely affecting the glass transition temperatures of the final polymers. Hydro-lysis of the uncrosslinked polymers in the form of films in deionized water at 37 degrees C showed between similar to 8 and 16% mass loss and between a similar to 28 and 88% molecular weight decline over 12 weeks. Polymers were also crosslinked using ultraviolet radiation for increasing amounts of time. Preliminary mechanical testing of the homo-citronellol polymer indicated increasing modulus and decreasing tensile strength with increased crosslink density. (c) 2014 Wiley Periodicals, Inc.