Flexible Cyclic‐Poly(phthalaldehyde)/Poly(ε‐caprolactone) Blend Fibers with Fast Daylight‐Triggered Transience

Cyclic‐poly(phthalaldehyde) (cPPHA) exhibits photo‐triggerable depolymerization on‐demand for applications like the photolithography of microfabricated electronics. However, cPPHA is inherently brittle and thermally sensitive; both of these properties limit its usefulness as an engineering plastic. Prior to this report, small molecule plasticizers are added to cPPHA‐based films to make the polymer more flexible. But plasticizers can eventually leach out of cPPHA, then leaving it increasingly more brittle throughout product lifetime. In this research, a new approach to fabricating flexible cPPHA blends for use as spun fibers is achieved through the incorporation of poly (ε‐caprolactone) (PCL) by a modified wet spinning method. Among blend compositions, the 50/50 cPPHA/PCL fiber shows fast transience (