Single-Crystal Linear Polymers Through Visible Light–Triggered Topochemical Quantitative Polymerization

Abstract

Topochemical Polymerization In a topochemical reaction, chemical changes start at active sites in the solid and then proceed autocatalytically to neighboring regions. If one starts with a monomer that can form ordered structures similar to the final polymer, it is possible to polymerize chains in a fully ordered state and thus make very long single chains. Dou et al. (p. 272 ; see the Perspective by Goroff ) describe an unexpected visible-light–induced polymerization of derivatives of a dye. Two of the derivatives underwent photoinduced single-crystal-to-single-crystal topochemical polymerization.

Fabrication of Large Single Crystals for Platinum‐Based Linear Polymers with Controlled‐Release and Photoactuator Performance

“…400 mm 15 mm) and good quality.The distance between adjacent polymer chains is approximately 9.498 .T he highly ordered alignment and weak intermolecular interactions of linear polymer chains make it possible to exfoliate materials into nanorods. [13] Adopting as imple mechanical exfoliation method similar to exfoliation of graphene,w ea re able to harvest well-dispersed nanorods with diameters approximately 10-20 nm as seen in transition electron microscopy (TEM) images (Figure 2e). Scheme 1.…”

“…To study the photoreaction process of poly(Pt-BA2DA), various characterization techniques including powder X-ray diffraction (PXRD), UV/Vis spectroscopy,s olid-state 13 CNMR and FT-IR were employed. Based on an in-house setup ( Figure S2), we successfully prepared gram-scale poly-(Pt-BA2DA) powder.…”

“…In addition, this photo-polymerization process can be tracked with sample color change from yellow to light yellow.UV/Vis spectroscopy revealed the absorption band at 445 nm in the visible region, ascribed to p-p*t ransition of anthracene,g radually disappear due to the loss of the conjugation after polymerization (Figure S3). [14] Solid-state 13 CNMR and FT-IR was used to further monitor the polymerization process.F or the monomer,t he primary peaks of aromatic anthracene (ranging 123.9 to 129.0 ppm), with partial overlap,c an be attributed to the similar electronic environments within anthracene (Figure S4). Additionally,t he carbon peak at 172.5 ppm assigned to -C=N-and the peak at 62.6 ppm assigned to the -CH 2 -o ft he ethanediamine linker can be identified by their standard chemical shifts.A fter irradiation, ac haracteristic signal at d = 66.2 ppm assigned to the bridgehead of dianthracene appeared.…”

Conjugated polymer single crystals and nanowires

“…For example, electrospinning is a simple method to prepare conjugated polymer nanowires . Topochemical polymerization is an effective method to prepare linear conjugated polymer single crystals …”

Realizing Long‐Range Orientational Order in Conjugated Polymers via Solventless Polymerization Strategy

“…[ 7,8 ] Nevertheless, realization of long‐range orientational order is one of the biggest challenges in polymer science, not limited to CPs. [ 9–14 ] At present, single‐crystalline polymers are mostly limited to linear polymers without heteroatoms, such as polyethylene, due to their ease to crystallize. [ 13–16 ] By comparison, the crystallization of CPs is more complicated due to easier rotational migration between molecules to reach the lowest energy state in the process of growth and more difficulty to control the growth rate.…”