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Different polylactic acid (PLA) thin films containing clarithromycin and a number of metal oxide nanoparticles (magnesium, titanium, zinc, and nickel) dioxides were created. Low dosages of metal oxides (0.01% by weight) and clarithromycin (0.5% by weight) were used to make transparent films. The role of metal oxide nanoparticles and clarithromycin as UV blockers for PLA photodegradation was looked at. The durability of polymeric materials is improved more by clarithromycin in combination with metal oxides than by clarithromycin alone in PLA films. An analysis of the weight loss, surface morphology, and changes in infrared spectra of irradiated polymeric blends revealed that nickel oxide and clarithromycin together function as effective UV blockers and offer PLA a high degree of protection. Nickel oxide nanoparticles were the best addition for PLA stability. Highly alkaline metal oxides are present. Contrarily, the heteroatom and aromatic nature of clarithromycin enables it to absorb damaging radiation and function as an ultraviolet absorption. Thus, the adaptability of PLA to photodegradation was significantly improved by using a mixture of metal oxide nanoparticles and clarithromycin.

One of the earliest manufactured and most frequently used resins is phenol formaldehyde (PF) resin. Even with lesser loadings, their characteristics can be enhanced by the addition of nano-ZnO. The novel PF/ZnO Nanocomposites synthesis by ultrasonic process. The optical properties of materials modified with wide-band gap semiconductor described via UV–vis spectroscopy. Diffuse reflectance spectroscopy (DRS) one of the possible tool to measure the reflected light from powders and rough surfaces clearly. Spectra obtained by DRS treated with Kubelka-Munk function in order to describe the energy band gap accurately for modified and pure para hydroxy benzoic acid polymer. The band gap of para hydroxy benzoic acid is about 4.5 eV and in modified samples range from 3.4 to 3.3 eV; the lowest band gap value corresponds to the higher ZnO concentration (0.005gm). The surface morphology characterize by SEM and AFM m where obtain the effected nanostructure as increase on the surface morphology and the roughness which is increase according the aggregation occur. EDX mapping appearance increase the distribution and present of zinc nanostructured in modified polymer. It was discovered that this was because of the ZnO NPs' good dispersion in the polymer matrix and their robust interfacial interaction with the PF matrix.

Polytetrafluoroethylene (PTFE) was mixed with silicon carbide nanoparticles in various quantities to create thin films. Long-term UV light exposure to the PTFE films was used to study the effects of SiC NPs as a photo-stabilizer by assessing changes in weight loss and surface shape. Comparing PTFE films with various SiC NP concentrations to the blank film, very little variation was seen. AFM and optical microscopy were also used to analyze the surface morphology of films. When PTFE films with additives were compared to blank film, there were hard to observe any negative changes brought due to photo-degradation. Additionally, the surfaces appeared more uniformly smooth hence SiC NPs work well as photo-stabilizers to impede photo-degradation, particularly 0.0005 gm weight. Silicon carbide nanoparticles absorb ultraviolet light, bind polymeric chains, scavenge radical moieties, and degrade peroxide residues.

To date, many approaches have been made to stabilize the chemical structure of PVC when exposed to sunlight in outdoor usage. This work includes utilizing mefenamic acid (1 % per polymer weight) as a new photo stabilizer unit to adjust PVC to enhance resistance to change under UV exposure. Modification by attaching a new unit that contains an aromatic substance could protect the polymer from UV light due to its ability to absorb it. Positive results were obtained, as the interaction between mefenamic acid and PVC succeeded, using the FTIR technique to characterize the chemical structure of the product. FTIR spectrum of modified PVC shows the disappearance of (OH) band in the region above 3200 cm−1 which is clear evidence that the connection between the polymer and mefenamic acid has happened through the OH group. In addition, we have investigated the influence of microparticle metallic oxides such as TiO2, and Cr2O3, using only 1 % per modified polymer weight, on the photodegradation process of PVC materials. Several approaches have been utilized to investigate the photo-stability of studied materials which are FTIR functional group indices, weight-loss percentage, microscopic images, SEM, and AFM. They demonstrated that modified PVC gives better stability after exposure to UV in comparison to unmodified PVC. It's interesting to note that adding titanium dioxide to modified PVC has increased the amount of UV protection by acting as a UV shielding agent and blocking the light's path to the polymer. Thus, chromium oxide has demonstrated the opposite findings because it functions as a photo-catalytic reagent that accelerated the photo-degradation process. This result may be interpreted as the decomposition of waste PVC, which poses a major threat to the marine ecosystem.

In this work it was used extracted lignin from oil palm empty fruit bunch by kraft delignification process as environmentally friendly photo-stabilizer of Poly (vinyl chloride) thin films. Up to date writing this paper, nobody has used this type of extracted lignin as PVC photo-stabilizer. Therefor this significant application was exhibited in this study by utilizing lignin as eco-friendly photo-stabilizer of PVC. Many approaches have been applied to test the efficiency of it as natural additive of PVC. Infrared spectra shows the growing of two specific bands during irradiation belong to carbonyl (CO) and alkene (CC) groups due to the photo-degradation. It was demonstrated that using lignin inhibits the formation of these two peaks substantially and stabilize the polymer. Various other experiments were done such as weight loss percentage, average molecular weight and surface study by AFM and SEM. All the results were in agreements and proved that lignin could be used as an excellent photo-stabilizer of PVC. Moreover it was demonstrated that increasing the concentration of lignin from 0.5% to 1% per polymer weight has increase the stability of PVC. It was also suggested the mechanism of stability hence lignin is highly aromatic and has a lot of phenolic hydroxyl groups which make it a very good UV-blocker and excellent free radical scavenger.

The growing of fossil fuel burning leads to increase CO2 and H2 emissions, which cause increasing of global warming that, has brought big attention. As a result, enormous researches have been made to reduce CO2 and H2 build up in the environment. One of the most promising approaches for managing CO2 and H2 gases percentage in the atmosphere is capturing and storage them inside proper materials. Therefore, the design of new materials for carbon dioxide and hydrogen storage has received increasing research attention. Four derivatives of coumarine linked to thiazolidinone were synthesized in good yields by reacting 3-(2-Phenylamino-acetyl)coumarine and 2-phenylimino thiazolidinone-4-one in a solution of anhydrous sodium acetate/ glacial acetic acid at 120° for 5–6 h. The synthesised organic compounds were identified by using different techniques such as 1H NMR, 13C NMR, FTIR, and energy dispersive X-ray spectra. The agglomeration, shape and porosity of the particles were determined utilizing scanning electron microscopy (SEM) and microscopy images analysis. The capacity of carbon dioxide (CO2) and hydrogen (H2) adsorption on the prepared organic materials at 323 K, 50 bar ranged from 22 to 31 cm3/g, and hydrogen from 4 to 12 cm3/g for the four synthesised compounds which contain phenyl substituted with chloro, nitro and bromo groups was found to be the most active adsorbent surfaces for carbon dioxide and hydrogen storage.

Many chemical changes have been made to poly(vinyl chloride) (PVC) in order to enhance its photo-stability features, the use of PVC in new applications, and the study of PVC-related phenomena. The chemical modification of PVC using captopril as a modifying agent is described in this paper. Infrared spectroscopy and energy dispersive X-ray analysis was used to characterize the modified polymer. Metal salts (HgCl2, CoCl2, ZnCl2, NiCl2, and CdCl2) were used to react with the modified film and form polymeric complexes. FTIR, weight loss percentage, AFM, EDX, and SEM approaches were used to analyze polymeric films that had been exposed to UV radiation for 300 hrs. The modified PVC complexes films have shown excellent stability against photo-degradation even after 300 h of irradiation by UV light. Thermogravimetry (TGA) was used to evaluate the thermal characteristics of the modified polymers, which demonstrated that the synthesized polymer complexation showed good thermal stability.

New four coumarin derivatives (9–12) compounds have been successfully synthesized from the reaction of salicyaldehyde and ethylacetoacetate yielding 3-acetyl coumarine, which on further treatment with bromine/chloroform gave 3-(2-Bromoacetyl) coumarine. Substituted 4-(Benzylidene-amino)-]triazole-3-thiol reacted with 3-(2-Bromoacetyl) coumarine to give 3-sulfanyl-acetyl-4-(Benzylidene-amino)-triazol related coumarin derivatives. The newly synthesized products were characterized with FTIR, 1H and 13C NMR, and energy dispersive X-ray spectra to confirm their chemical structures. All above used techniques demonstrated the formation of target products with high percentage of purity. The synthesised compounds (9–12) have been investigated as organic additives to protect poly(vinyl chloride) (PVC) from photo-degradation at (λmax = 313 nm) and irradiation period 300 h in the atmosphere. The stabilizing efficiencies of blended PVC films were examined by detecting changes in their infrared spectra, weight, and average molecular weight viscosity. A light microscope, atomic force microscopy, and a scanning electron micrograph were all used to examine the surface morphology of the films. The additives enhanced considerable resistance of films against irradiation and the polymeric surface was significantly smoother in the presence of the coumarine derivatives compared with the blank film. The strongest photo-stabilization effect was seen in coumarine derivative (12) containing 2-hydroxy naphthol the most effective as UV absorber, free radical scavenger, and quencher. This phenomenon appears to allow energy to be transported through resonant aryl rings and various intersystem crossover mechanisms.

The high quantity of carbon dioxide in the atmosphere, which has been steadily increasing year after year, has had a significant influence, particularly on the environment, resulting in climate change and global warming. As a result, numerous approaches, like the Schiff bases, have reported extensive investigation into storing this gas. We synthesized four new Schiff bases containing the amlodipine medication and tested them as CO2, CH4 and H2 storage. In boiling methanol as a solvent, amlodipine reacts with (p-Chlorobenzaldehyde, p-hydroxy benzaldehyde, vanillin, terphthaldehyde) to generate COFs. Scanning electron microscopy (SEM), and atomic force microscopy (AFM) were utilized to study the features of the surface for synthesized compounds. Schiff bases have surface areas, pore volumes cm3/g, and pore widths, according to the Brunauer-Emmett-Teller (BET) test. At temperature (313 K) and pressure (40 bars), the produced Schiff bases obtained reasonable CO2 (26.3 cm3/g) CH4 (30.1 cm3/g) and H2 (2.5 cm3/g) absorption values.