Ohzono, Takuya published the artcileInternal constraints and arrested relaxation in main-chain nematic elastomers, Synthetic Route of 7575-23-7, the main research area is nematic liquid crystal elastomer mech optical property.
Nematic liquid crystal elastomers (N-LCE) exhibit intriguing mech. properties, such as reversible actuation and soft elasticity, which manifests as a wide plateau of low nearly-constant stress upon stretching. N-LCE also have a characteristically slow stress relaxation, which sometimes prevents their shape recovery. To understand how the inherent nematic order retards and arrests the equilibration, here we examine hysteretic stress-strain characteristics in a series of specifically designed main-chain N-LCE, investigating both macroscopic mech. properties and the microscopic nematic director distribution under applied strains. The hysteretic features are attributed to the dynamics of thermodynamically unfavored hairpins, the sharp folds on anisotropic polymer strands, the creation and transition of which are restricted by the nematic order. These findings provide a new avenue for tuning the hysteretic nature of N-LCE at both macro- and microscopic levels via different designs of polymer networks, toward materials with highly nonlinear mech. properties and shape-memory applications.
Nature Communications published new progress about Crosslink density. 7575-23-7 belongs to class alcohols-buliding-blocks, name is Pentaerythritol tetra(3-mercaptopropionate), and the molecular formula is C17H28O8S4, Synthetic Route of 7575-23-7.
Referemce:
Alcohol – Wikipedia,
Alcohols – Chemistry LibreTexts