Synthesis of high‐molecular‐weight linear methacrylate copolymers with spiropyran side groups: Conformational changes of single molecules in solution and on surfaces

Abstract

P(BMA-co-HEMA-spiropyran) was synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization of butyl methacrylate (BMA) and 2-(trimethylsilyloxy)-ethyl methacrylate (HEMA-TMS), removal of the TMS-protective groups, and the polymer analogous esterification of the hydroxyethyl side chains with a spiropyran containing a carboxylic acid group. UV-induced conformational changes of the synthesized macromolecules and low-molecular-weight spiropyran molecules were studied. Rate constants and half-life times of the ring closure reaction from zwitterionic merocyanine to the spiropyran species were determined in the presence and absence of mica-dispersed particles in toluene both with the free spiropyran and the polymer-bound spiropyran. Scanning force microscopy was used to visualize the conformation of spiropyran-decorated single macromolecular chains and agglomerated polymer-bound merocyanine adsorbed on mica.

Synthesis and photochromic response of a new precisely functionalized chitosan with “clicked” spiropyran

“…The enhanced life-time of merocyanine in PH-SP can be explained by the polysaccharide inducing polar environment (Adelmann, Mela, Gallyamov, Keul, & Moeller, 2009;Liu, Jiang, Liang, & Gao, 2005), which stabilizes more MC-I form than MC-II (Kim, Oh, Kim, Cha, & Kang, 2008;Nakao, Noda, Horii, & Abe, 2002;Smets, 1983). Furthermore, the chemical linkage between SPCC and the polymer (Smets et al, 1983) limits the conformational mobility of the corresponding merocyanine which cannot easily rotate and isomerize.…”

Scanning Force Microscopy as Applied to Conformational Studies in Macromolecular Research

“…Therefore, it would be more convenient to explore much faster light-induced conformation transitions in the permanent presence of some vapour just promoting required macromolecular mobility on a substrate. [316][317][318] Peculiarities of Vapour-induced Conformational Transformation as Described Quantitatively…”

Living Radical Polymerization by the RAFT Process - A Second Update

“…For an efficient RAFT polymerization (Scheme 1, Fig. 3 22* [86] S S MA [54] AAEMA [87] MAEP [87] MMA [88,89] AEMA [90] DMAEMA [91] (TPMMA) [92] TFPMA [93] St [48,94,95] 277 [96] 278 [96] 392 [97,98] 345 [99] 348 [100] 347 [101] St [51] 364 [102] 365 [102] NVP [103] 385 [104] 386 [98] 387 [104] 388 [104] 389 [104] 390 [104] BA/ 407 [105] St/MAH [53] AAEMA-b-AEP [87] AAEMA-b-MAEP [87] MAEP-b-AAEMA [87] BMA/TMSEMA [106] TFPMA-b-tBA [93] St-b-NIPAM [95] St-b-HEMA/DMAEMA [86] 364-b-384 [102] 365-b-384 [102] 386-b-392 [97] 23* [107] S CN S DEGMA [108] EGMA [108] MAA [108] MMA [109] PEGMA …”

“…[540] The general approach has wide application and has, for example, been used in the synthesis of photochromic polymers by coupling of spiropyran moieties to RAFT-synthesized P(BMA-co-HEMA). [106] Grafting-Through Processes This approach requires attaching monomer functionality to the substrate which may be:…”