Enhancement of Photostabilization of Poly(Vinyl Chloride) in the Presence of Tin-Cephalexin Complexes.

Poly(vinyl chloride), PVC, has many attractive properties, including low cost of manufacture, resistance to acid and alkali corrosion, and ease of molding. However, PVC suffers from aging in harsh conditions, leading to the shortening of its useful life. Stability to irradiation, for example, can be improved through the incorporation of additives to PVC.

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

Poly(vinyl chloride) (PVC) is an important synthetic plastic that is produced in large quantities (millions of tons) annually. Additives to PVC are necessary to allow its use in many applications, particularly in harsh conditions. In regard to this, investigation of the synthesis of trimethoprim-tin complexes and their use as PVC additives is reported.

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

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.

Tin Complexes Containing an Atenolol Moiety as Photostabilizers for Poly(Vinyl Chloride).

The lifetime of poly(vinyl chloride) (PVC) can be increased through the addition of additives to provide protection against irradiation. Therefore, several new tin complexes containing atenolol moieties were synthesized and their photostabilizing effect on PVC was investigated. Reacting atenolol with a number of tin reagents in boiling methanol provided high yields of tin complexes.

Encapsulation of Cinnamic Acid by Cucurbit[7]uril for Enhancing Photoisomerization.

- or -configuration is required for the plant growth-promoting activity of cinnamic acid (CA), whereas the -form is inactive. Herein, we describe the encapsulation of -CA by cucurbit[7]uril (CB7) and show that photoisomerization reactions can be more efficiently controlled in aqueous solutions by utilizing this supramolecular approach. Measurements of UV-visible absorption and proton NMR spectra at different pH values confirm that -CA and its methyl ester, methyl--cinnamate (MC), form stronger 1:1 host-guest complexes with CB7 compared to cucurbit[8]uril (CB8) or three cyclodextrins (α-, β-, and γ-CD).

Solubilization of Pyridone-Based Fluorescent Tag by Complexation in Cucurbit[7]uril.

Aimed at further exploring the hosting properties of cucurbit[7]uril (CB7), we have exploited the spectroscopic and photophysical properties of a known fluorescent label as the guest molecule, namely, 3-cyano-6-(2-thienyl)-4-trifluoromethyl pyridine (TFP), in neat solvents. The formation of an inclusion host-guest complex with CB7 was checked by UV-vis absorption spectroscopy, and the value of binding constant (9.7 × 10 M) was extracted from the spectrophotometric data.

Time-resolved photoluminescence of 6-thienyl-lumazine fluorophores in cellulose acetate nanofibers for detection of mercury ions.

Time-resolved photoluminescence measurements were used to characterize the photophysical properties of 6-thienyllumazine (TLm) fluorophores in cellulose acetate nanofibers (NFs) in the presence and absence of mercuric acetate salts. In solution, excited-state proton transfer (ESPT) from TLm to water molecules was investigated at pH from 2 to 12. The insertion of thienyl group into lumazine introduces cis and trans conformers while keeping the same tautomerization structures.