Synthesis of Carvedilol–Organotin Complexes and Their Effects on Reducing Photodegradation of Poly(Vinyl Chloride)

Abstract

Poly(vinyl chloride) (PVC) undergoes photodegradation induced by ultraviolet (UV) irradiation; therefore, for outdoor applications, its photostability should be enhanced through the use of additives. Several carvedilol tin complexes were synthesized, characterized and mixed with PVC to produce thin films. These films were irradiated at 25 °C with a UV light (λ = 313 nm) for up to 300 h. The reduction in weight and changes in chemical structure and surface morphology of the PVC films were monitored. The films containing synthesized complexes showed less undesirable changes than the pure PVC film. Organotin with a high content of aromatics was particularly efficient in inhibiting photodegradation of PVC. The carvedilol tin complexes both absorbed UV light and scavenged radicals, hydrochloride, and peroxides and, therefore, photostabilized PVC.

FTIR, Weight, and Surface Morphology of Poly(vinyl chloride) Doped with Tin Complexes Containing Aromatic and Heterocyclic Moieties

“…It has been reported that PVC containing nickel chloride and a dithiazole Schiff base or tin–naphthalene sulfonic acid complex led to the formation of honeycomb-like structures [ 31 , 38 ]. In addition, PVC blended with a Schiff base containing a melamine unit showed an ice–rock structure [ 36 ]. Such observations could be attributed to the slow rate of HCl elimination from the PVC chains during photoirradiation.…”

“…Banned additives include flame retardants (e.g., chlorinated biphenyls), plasticizers (e.g., phthalates), stabilizers (e.g., phosphites), and those containing metals [ 20 , 21 , 22 , 23 ]. Various additives such as polyphosphates [ 24 ], polybenzimidazoles [ 25 ], metal oxides [ 26 , 27 , 28 ], pigments [ 29 ], Schiff bases [ 30 , 31 , 32 , 33 , 34 ], and substituted tin complexes containing aromatic moieties [ 35 , 36 , 37 , 38 ] have been used to improve photostability of PVC.…”

Photostabilization of Poly(vinyl chloride) Films Blended with Organotin Complexes of Mefenamic Acid for Outdoor Applications

“…A long period of PVC photoirradiation leads to surface damage mainly as a result of chain scission and dehydrochlorination [58]. Non-irradiated PVC films have a more or less smooth surface with no noticeable irregularity compared with irradiated ones [21,39,40]. The surface of an irradiated PVC was inspected using an optical microscope.…”

“…The biological performance of organotin compounds is dependent on the nature of organic units and the number and types of substituents (alkyl or aryl) present [38]. We recently successfully synthesized various organotin complexes and investigated their uses as PVC photostabilizers [39][40][41][42][43][44][45][46][47]. Continuing our interest in the polymer photostabilization subject, we can now report the successful synthesis of different tin complexes containing the mefenamic unit and their effect in enhancing the PVC photostabilization.…”

Tin Complexes of 4-(Benzylideneamino)benzenesulfonamide: Synthesis, Structure Elucidation and Their Efficiency as PVC Photostabilizers

“…The efficiency of tin complexes is highly dependent on the organic moieties and substituents attached to the tin (Sn) atom [39]. Several tin complexes containing different aromatic moieties have been used to stabilize PVC against UV irradiation [40][41][42][43]. For example, tin complexes containing naphthalene sulfonic acid have been proven to be efficient in reducing the roughness factor (Rq) of PVC blends when irradiated with UV light for durations of up to 300 h [43].…”