Research Initiation Award Grant: Synthesize and Characterize of Disulfonated Poly(arylene ether sulfone-tetrachlorocyclotriphosphazene) Hybrid Copolymers

菲斯克大学的研究启动奖题为-合成和表征二磺化聚（芳醚砜-四氯环三磷酸hazene）杂化共聚物-目标是合成二磺化聚（芳醚砜-四氯环三磷酸hazene） （PAES-TCCP）杂化共聚物作为燃料电池的质子交换膜（PEM）。迄今为止，聚合物膜的质子导电性还不够好，无法用于燃料电池。该项目将结合六氯环三磷腈（HCCP）单体与二磺化聚芳醚砜（PAES）共聚物的独特性能，制备出具有更高亲水性、高质子导电性、热稳定性和机械性能的新型杂化聚合物。然而，通常报道的对HCCP预成型聚合物进行改性的苛刻后磺化反应会导致不可复制和交联的产物。为了克服这些限制，提出了一种制备二磺化线性PAES-TCCP杂化共聚物的两步法。第一步，制备基于六氯环三磷腈和双酚类单体的杂化单体；双酚单体的酚端基将作为聚合的反应位点，以克服与HCCP单体相关的位阻，从而增加聚合物的分子量。其次，通过与非磺化4,4′-二氯二苯砜（SDCDPS）和非磺化4,4′-二氯二苯砜（DCDPS）直接共聚，合成线性PAES-TCCP杂化单体。聚合前在HCCP上保留氯化物将允许沿着聚合物主链进行后修饰，从而提供进一步的活性位点，随后结合各种官能团。预期的产物将具有改进的质子电导率和可控的交联。该项目涉及菲斯克大学从事最先进聚合物研究的本科生，他们来自代表性不足的背景。学生参与研究的所有主要方面，通过实践经验增加他们对聚合物化学的兴趣。菲斯克学生的本科研究进一步为他们在聚合物相关领域的职业生涯中获得硕士或博士学位做准备。

Fisk University's Research Initiation Award entitled - Synthesize and Characterize of Disulfonated Poly(arylene ether sulfone-tetrachlorocyclotriphosphazene) Hybrid Copolymers - has the goal to synthesize disulfonated poly(arylene ether sulfone tetrachlorocyclotriphosphazene) (PAES-TCCP) hybrid copolymers as proton exchange membranes (PEM) for fuel cells. Polymer membranes created to date are insufficiently proton conductive to be useful for fuel cells. The project will combine the unique properties of hexachlorocyclotriphosphazene (HCCP) monomer with disulfonated poly(arylene ether sulfone) (PAES) copolymer to prepare novel hybrid polymers with increased hydrophilicity, high proton conductivity, thermal stability, and mechanical properties. However, harsh post sulfonation reactions typically reported to modify HCCP preformed polymers led to both irreproducible and crosslinked products. To overcome these limitations, a two-step method for preparing disulfonated linear PAES-TCCP hybrid copolymers is proposed. In the first step, hybrid monomers based on hexachlorocyclotriphosphazene and biphenols monomers will be prepared; the phenolic endgroups of the bisphenol monomers will serve as the reactive site for polymerization to overcome the steric hindrance associated with the HCCP monomer, thus increasing polymer molecular weight. Secondly, linear PAES-TCCP hybrid copolymers will be synthesized by direct copolymerization of the hybrid monomers with disulfonated 4, 4'-dichlorodiphenylsulfone (SDCDPS) and unsulfonated 4, 4'-dichlorodiphenylsulfone (DCDPS) monomers. Retention of the chlorides on HCCP prior to polymerization will allow post-modifications to be carried out along the polymer backbone, providing further reactive sites to subsequently incorporate various functional groups. The expected products will have improved proton conductivity and controlled cross-linking.This project involves undergraduate students from under-represented backgrounds in state-of-the-art polymer research at Fisk University. Students participate in all major aspects of the research, increasing their interest in polymer chemistry through hands-on experiences. Undergraduate research by Fisk students further prepares them to obtain M.S. or PhD degrees for careers in the polymer-related fields.