Polymerizable UV absorbers for the UV stabilization of polyesters. I. Design, synthesis and polymerization of a library of UV absorbing monomers

Poly(ethylene terephthalate) (PET) absorbs strongly in the ultraviolet (UV) region of the EM spectrum (Figure 1), and this can lead to photodegradation of the polymer chains and loss of polymer properties. UV stabilizer additives are normally employed to suppress the UV-induced photodegradation of polyester films, especially for those applications where the levels of UV exposure to the polymer film are high, e.g., photovoltaic cells. One limitation concerning the use of UV stabilizers is the loss of additive from the polymers over time by leaching, since UV stabilizers are normally low molar mass organic compounds that can be washed out through weathering actions, and this reduces their effectiveness. One way in which this leaching problem can potentially be circumvented is to lock the UV stabilizers into the polymer chains through covalent bond