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Calcium terephthalate anhydrous salts (CATAS), synthetized by reaction of terephthalic acid with metal (Ca) oxide were incorporated at different weight contents (0-30 wt. %) in recycled Poly(ethylene terephthalate) (rPET) by melt processing. Their structure, morphology, thermal and mechanical properties (tensile and flexural behavior) were investigated. Results of tensile strength of the different formulations showed that when the CATAS content increased from 0.1 to 0.4 wt. %, tangible changes were observed (variation of tensile strength from 65.5 to 69.4 MPa, increasing value for E from 2887 up to 3131 MPa, respectively for neat rPET and rPET_0.4CATAS). A threshold weight amount (0.4 wt. %) of CATAS was also found, by formation at low loading, of a rigid amorphous fraction at the rPET/CATAS interface, due to the aromatic interactions (π-π conjugation) between the matrix and the filler. Above the threshold, a restriction of rPET/CATAS molecular chains mobility was detected, due to the formation of hybrid mechanical percolation networks. Additionally, enhanced thermal stability of CATAS filled rPET was registered at high content (T max shift from 426 to 441 °C, respectively, for rPET and rPET_30CATAS), essentially due to chemical compatibility between terephthalate salts and polymer molecules, rich in stable aromatic rings. The singularity of a cold crystallization event, identified at the same loading level, confirmed the presence of an equilibrium state between nucleation and blocking effect of amorphous phase, basically related to the characteristic common terephthalate structure of synthetized Ca-Metal Organic Framework and the rPET matrix.

Recently the synthesis and application of bio-based composite materials, which contain polymeric and inorganic units such as TiO 2 , has gained much attention in the field of water/wastewater treatment, due to their better (and more practical) performance parameters. In the present study, recycled poly(ethylene terephthalate) (PET) has been used and evaluated as supporting polymer for Aeroxide P25 TiO 2 immobilization. PET-TiO 2 composite films were synthesized at different TiO 2 content (10%, 30% and 47% TiO 2 ) and characterized with different techniques such as X-ray Powder Diffraction (XRD), Thermogravimetric analysis (TGA), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM), etc. The photocatalytic activity of the new (synthesized) bio-based TiO 2 composite films was investigated under simulated solar irradiation for the degradation of a mixture of antibiotic pharmaceuticals (Isoniazid, Metronizadole, Sulfadiazine, Sulfamethoxazole, Trimethoprim, Norfloxacin, Moxifloxacin and Lincomycin). The immobilization of TiO 2 was successful in all cases and by increasing the photocatalyst concentration results in higher photocatalytic efficiencies. The new composite films were tested two times to assess their reusability, which found to be better for PET-10%-TiO 2 composite films; therefore the latter has been used for further investigation thus exhibiting good stability even after five cycles. The results showed that PET-10%-TiO 2 was efficient in degrading the antibiotic mixture in water and in wastewater matrix., (Copyright © 2019 Elsevier Ltd. All rights reserved.)