Multi-modal Mecdanophores: Synthesis And Mechanoresponsive Properties

Mechanochemistry,or mechanically-induced chemical changes in polymeric materials are attracted vast attentions because of the specific activation behaviors of mechanical force.Mechanoresponsive polymers have enriched the content of responsive materials.It is of great importance to explore novel mechanophores to access advanced stress-responsive materials.So far,most reported mechanophores show one type of respones to load but it is highly desired to integrate several useful respones in one mechanophore.Here,we focus on exploring multi-modal mechanochemically-responsive mechanophores and embeding it into parallel connected mechanophores.First,a novel multi-modal mechanochemically-responsive mechanophore-non-scissile cinnamate dimer(nCD)mechanophore is synthesized.The nCD mechanophore can be activated by mechanical force in solutions,it can response to load in a form of mechanochromism,and it may have latent applications in self-healing materials,also it can achieve chain length relief.Basing on nCD mechanophore we developed a asymmetric parallel connected mechanophore by combining the bicyclo[4.2.0]octane mechanophore with nCD mechanophore.Given the mechanochromism of the nCD mechanophore cannot be sensed by naked eye,a new rhodamine derivatives(Rho-NH2)mechanophore is synthesized and incorporated into the backbone of PMA.The Rho-NH2 mechanophore can be activated by mechanical force both in solutions and polymeric films.In solutions,the ring-opening of Rho-NH2 mechanophore can be reversed by heating.Then,we will try to resolve the weakness of nCD mechanophore by combining those two mechanophores.