Photoluminescent Mechanoresponsive Polymers

Schematic of mechanoresponsive polymer

Problem

Mechanoresponsive polymers are a class of materials that demonstrate specific property changes induced by mechanical stimuli. The design of mechanoresponsive polymers capable of self reporting mechanical stress is of high importance not only for preventing the materials’ failure, but also for the better understanding of polymer response to mechanical force. However, the majority of commonly used mechanophores (stress or strain activated molecular units of mechanoresponsive polymers) are based on organic molecules with an irreversible response, or a slow recovery. This hinders the development of a mechanical stress probe that can visualize subtle stress changes repeatably.

Solution

This invention overcomes the above problems by providing a photoluminescent copper containing compound used as a cross linker in elastomeric polymers to provide a material that shows response to mechanical stress. Methods are provided to prepare a material which changes photoluminescence intensity in response to mechanical stress, measurable by spectroscopic methods or by direct imaging. Using the aforementioned copper containing cross linkers, reversible, repeatable and fast response to mechanical stimulus is achieved.