A NEW PSEUDOPHOTOCHROMIC BENZOTHIAZOLES DOPED PVC FILMS

Under the influence of the UV light in 2-aryl substituted benzothiazol es doped PVC films take shapes. a new pseudophotochromic system. The c oloured films were formed by two processes - the liberation of HCl dur ing the photodegradation of PVC and an interaction between HCl and 2-a rylsubstituted benzohiazoles (BT). They can return thermally to the co lourless films and this process depends on the stability of the comple xes BTH+.Cl-. Reversible photochromism was observed in the films on re peating irradiation with UV light. The experimental results, possible applications and future work on this pseudophotochromic system are als o discussed.