Perfluorocyclobutane Aryl Ether Polymers

This chemistry was also performed on one trisphenol, 1,1,1 -tris(4-hydro-xyphenyl)ethane (THPE). The resulting tris(trifluorovinyl ether) monomer forms a thermoset polymer upon curing. 

This research was an attempt to develop new polymers with the mechanical properties of polyarylene ethers and the dielectric properties of fluoropolymers. After initially testing the viability of the [2n+ 2n] cyclodimerization reaction for preparing high-molecular-weight polymers and testing the dielectric properties of these polymers, two polymers (one thermoplastic and one thermoset) were prepared in larger quantities to evaluate the thermal and mechanical performance of these novel compositions. The high Tg thermoset was also quantitatively tested for thermal/oxidative stability. 

---

Novel polymers containing alternating perfluorocyclobutane and aromatic ether subunits have been prepared by polymerization of aryl trifiuorovinyl ether monomers via the thermal [2tc -h 2n cyclodimerization of the trifiuorovinyl ether functionality (Scheme XII) (5(5). The dimerization of the trifiuorovinyl ether moiety is not a concerted pericyclic reaction, rather proceeds through a diradical intermediate. Dimerization affords predominately 1,2-substituted perfluorocyclobutane rings with a mixture of cis and trans isomers. Both linear and crosslinked polymer systems were synthesized using bis- and tris(trifluorovinyoxy) monomers, respectively. These polymers display both a low dielectric constant (2.5) and very low moisture absorption. 

---