Non-symmetric mechanophores prepared from radical-type symmetric mechanophores: bespoke mechanofunctional polymers

Abstract

An non-symmetric radical-type mechanophore (CF/ABF) was synthesized by the molecular crossing between two radical-type mechanophores. Thermal stability and mechanoresponsiveness of CF/ABF were found to be tunable by the properties of...

Mechanochemical Reactivity of Bottlebrush and Dendronized Polymers: Solid vs. Solution States

“…[48][49][50] BMG,d espite its long history in the field, [51][52][53] has only recently saw ar esurgence in its popularity as as olid-state method. [36,37,43,[54][55][56] With US,simple linear polymers undergo chain-centered scission, with scission rates that are dependent on molecular weight;specifically,rates increase with increasing molecular weight. [50] Below al imiting molecular weight (M lim )the generated elongational forces are not great enough to cause chain scission.…”

“…US has emerged as the most popular solution‐state method for conducting polymer mechanochemistry [48–50] . BMG, despite its long history in the field, [51–53] has only recently saw a resurgence in its popularity as a solid‐state method [36, 37, 43, 54–56] . With US, simple linear polymers undergo chain‐centered scission, with scission rates that are dependent on molecular weight; specifically, rates increase with increasing molecular weight [50] .…”

Action of Mechanical Forces on Polymerization and Polymers

“…Focus is placed on the printability and postprinting of latent MPs and fluorogenic print components. Chen et al [ 81 ], Calvino et al [ 82 ], Zhang et al [ 83 ] and Yanada et al [ 84 ] showed that choosing the correct MP–polymer combination for a specific application is very important when taking into account the MP activation method and the physico-mechanical properties of the polymer in accordance with the requirements for it.…”

Heterocyclic Mechanophores in Polymer Mechanochemistry

“…The weak bonds are defined as chemical bonds with a bond-dissociation energy (BDE) of less than 72 kcal mol -1 ; they are generally found in acyclic structures. These include covalent bonds such as diazo, 23,47 C-S, [48][49][50] C-C (in tetraarylsuccinonitrile), 25,28,[51][52][53][54][55][56] C-O, 50,57,58 S-S, [59][60][61][62] (Figure 2a), and coordinative bonds such as Ru-carbene, Ag-carbene, or Cucarbene bonds, 16,63 Fe-Cp (in ferrocene), [64][65][66] Pt-acetylide, 67 Fe-pyridine, 68 Cu-naphthalene, 69 Pd-phosphine, 70 and Pdcarbene (Figure 2b). 71 Covalent bonds in strained ring structures have lower BDEs than the analogous linear structures and can respond to mechanical forces.…”