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In this article, we developed a series of new nontoxic polymeric UV-absorbers through covalently attaching a benzophenone derivative onto the main chain of poly(vinyl chloride) (PVC) via mild and quantitative click chemistry. Azide groups were firstly introduced into the backbone of PVC via a nucleophilic reaction without affecting polymeric skelet...
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... They can be divided into inorganic (physical) and organic (chemical) agents [2]. UV blockers are sunscreen formulations' components and protect against harmful radiation by reflecting, scattering, or absorbing UV rays [3][4][5]. Depending on the type of photoblocker, the mode of their action is different. Inorganic filters usually reflect or scatter ultraviolet radiation via an optical mechanism [6,7]. ...
Unlike in many countries, in the USA, UV filters are treated as drugs and strictly regulated by the Food and Drug Administration. So far, 17 physical and chemical sunscreen agents were approved there to protect against the harmful effects of UV irradiation. In the European Union, access to UV filters is much larger, which gives manufacturers more options to create new sunscreen products in the form of lotions, sprays, oils, creams, gels, pastes, and sticks. Recently, concerns have been raised about the potential unfavorable effects of some UV filters that can penetrate the skin and enter into the systematic circulation. In this study, we prepared oil-in-water emulsions containing two commonly applied sunscreen agents, avobenzone and octyl methoxycinnamate. The formulations were characterized by a high stability at room temperature and a pH in the range of 6.02–6.11. The processes of sunscreen agent release and permeation were performed in a receptor fluid with a pH 5.8 using Strat-M and cellulose membranes to mimic the skin. It was proved that octyl methoxycinnamate exhibited different liberation and permeation patterns than avobenzone, mostly due to its higher lipophilicity. Both processes were also influenced by the type of membrane applied. The liberation of UV filters to the receptor fluid via the cellulose membrane depended on their concentration in the emulsion. As the amount of sunscreen agent in the formulation increases, more of its molecules diffuse to the receiving medium after 48 h. The permeation of the UV filters through the Strat-M membrane occurs at a very low level, 2% for octyl methoxycinnamate and 0.3% for avobenzone, which supports the safety and efficacy of the topical formulations obtained.
... Another mechanism involves the Photo-Fries rearrangement, which produces a compound with UV absorption ability, such as salicylate. These compounds do not possess an intrinsic UV absorption capacity, but their structures, generated through the Photo-Fries rearrangement, can reduce or eliminate UV radiation damage by releasing or consuming UV energy as low-energy radiation [14]. Researchers have made significant progress in developing new and more effective UV absorbers. ...
Exposure to ultraviolet (UV) light is known to cause skin aging, skin damage, cancer, and eye diseases, as well as polymer material aging. Therefore, significant attention has been devoted to the research and development of UV absorbers. Considering the robust hydrogen bonding and conjugated structure present in nitrogen-containing polycyclic compounds, these compounds have been selected as potential candidates for exploring ultraviolet absorption properties. After structural optimization and the simulation of ultraviolet absorption spectra, four tris-[1,2,4]-triazolo-[1,3,5]-triazine (TTTs) derivatives, namely TTTB, TTTD, TTTJ, and TTTL, were selected as the preferred compounds and synthesized. The structure of the compound was determined using various analytical techniques, including FTIR, 1HNMR, 13CNMR, HRMS, and XRD. Subsequently, composite films of polyvinyl chloride (PVC) and TTTs were produced using a simple solvent casting technique. The PVC films were subjected to UV age testing by exposing them to an ultraviolet aging chamber. The age-resistant performance of the fabricated films was evaluated using an ultraviolet spectrophotometer and Fourier infrared spectrum instrument. The findings suggest that TTTs exhibit a noteworthy capacity for absorbing ultraviolet radiation. The TTTL compound exhibits a superior UV absorption performance compared to commercially available UV absorbers such as UV-0 and UV-327 in the market.
... For example, fabrication of hybrid materials [13] by immobilization of UV absorbers onto an inorganic support [14,15]; or by intercalating an UV absorber into layered double hydroxides [16] allowed to improve the performances of UV absorbers in stabilizing polypropelene or polyurethane. A more traditional approach is to increase molecular weights in the forms of oligomeric or polymeric UV absorbers via chain-growth copolymerization [9], attaching UV absorbing molecules onto polymer backbones [17], or onto polyfunctional compounds (i.e. polyols, polycarboxylic acid etc.). ...
Benzylidene malonates constitute an important commercialized class of light stabilizers that are able to inhibit undesired photodegradation in polymers and plastics. However, the benzylidene malonate type of structures has yet to be FDA-approved for food-contact applications due to migration issues. Herein we report the design, synthesis and migration studies of three macromolecular benzylidene malonates (MBMs 1–3) by varying their structures, molecular weight and chemical composition. All MBMs were characterized with nuclear magnetic resonance spectroscopy, thermo-gravimetric analysis, photodegradation resistance property, resistance to yellowing upon UV exposure and migration studies using five different food simulants. Notably, the migration profiles of all MBMs are improved in comparison to the low molecular weight benzylidene malonate BM-4. The performance of MBM-3 synthesized by anchoring benzylidene malonate units to a poly(ethylene-co-acrylic acid) backbone against migration and photodegradation is the best amongst our three products and on par or better than the one of Uvinul® 3030 – an FDA-approved light stabilizer for food contact applications.
... Eliminating the HCl yields to forming polyene compounds that associated with carboncarbon double bonds. Dehydrochlorination of the PVC follows up a degradation in the thermal and physical properties, such as discoloration, which hinders its external applications [11,12]. PVC cannot absorb the high wave UV light (λ > 220 nm); therefore, polyene chains are initiated because of defects existed from PVC photodegradation [13,14]. ...
Poly(vinyl chloride) (PVC) could be considered as one of the highly manufactured plastics with a production capacity of multiple millions tons per year. Fillers are recently added to PVC in an attempt to increase its applications in various sectors, especially at tough exposing conditions. Therefore, the current work reports the morphological studies of PVC sheets that contain trimethoprim-tin complexes as additives. The PVC was blended with a low concentration of trimethoprim-tin complexes and thin films have been prepared from the homogenous mixtures. The ultraviolet irritation impact on the morphology and physicochemical properties of the films was studied. It was found that the photodecomposition and photo-oxidation levels of PVC films were lower than the blank film’s ones. The TEM images showed that the undesirable changes in the surface of irradiated PVC films, such as the appearance of dark spots, cracks, and roughness, were minimized once the tin complexes were filled compared with the blank PVC.
... Plastics have a wide range of chemical and physical qualities as well as inexpensive manufacturing costs. They are mass-produced and used in a variety of industrial applications [1][2][3]. However, in recent years, both academic and industrial companies have been under intense work to address issues arising from the usage of plastics. ...
Three arms Schiff base unit based on melamine moiety was synthesized and introduced to polyvinyl chloride (PVC) to produce a modified PVC polymer. The polymer composite of new modified PVC polymer was blended with micro copper oxide as a reflecting mirror of UV light to enhance the photostability of PVC. Three different concentrations of micro copper oxide (0.01–0.03 wt.%) were mixed with the modified PVC and cast as a thin film. The photostability test has shown high resistance to photodegradation upon exposure to UV light. In this work, different approaches were applied to examining doped modified PVC's thin film efficiency against photodegradation after exposure to UV light for 300 h in an ambient atmosphere. The exhibited studies, such as infrared spectroscopy and weight loss percentage, have demonstrated the improvement of photophysical properties for modified PVC and blended modified films in comparison to blank PVC polymeric films. These outcomes are so interesting as they could contribute to reducing the consumption of PVC around the world hence its waste causing huge environmental problems for the marine ecosystem.
... When the UV light hits the benzophenone, the energy is absorbed, causing the molecules to excite and break the hydrogen bonds, which transport the proton from a hydroxyl group to the carbonyl group. To date, benzophenone is the most widely used absorber, even though its price is high and it absorbs a lower amount of UV light than benzotriazoles [183]. Finally, the third category, the HALS, acts differently than both benzotriazoles and benzophenones by functioning as polymer degradation inhibitors instead of absorbing the UV light. ...
The conventional coatings are generally unsustainable in harsh environments and offer limited protection to the intended infrastructures. Recently, the emergence of plant-based components to enhance coatings has attracted significant attention due to their characteristics of anticorrosion, antifouling, antimicrobial, self-healing, and ultraviolet (UV) shielding. Almost all plant parts can be utilized as a potential material of interest, including leaves, flowers, oils, seeds, and fruits. The reason is that the extract from these parts possesses many phytochemicals that contribute to the properties stated above. In the coating industry, plant extract is introduced as a green additive and is said to share similar functions as synthetic additives, which is to enhance the protection ability of the coating. Moreover, they are non-toxic, safe to use, abundant, and environmentally- friendly.
... BPs are present in coatings, pigments or dyes in the packaging industry and are used to add flavor to frozen dairy products, beverages and candies (IARC Working Group on the Evaluation of Carcinogenic Risks to Humans, 2013; National Center for Biotechnology, 2021). The leaching of BPs from plastic materials is due to BPs' low molecular weight, their noncovalent interactions with polymers and the incompatibility between BPs and polymers (Huang et al., 2016;Johns et al., 2000;Rusko et al., 2020). Leaching of BPs from packaging, into the food contained within, exposes both humans and the environment to BPs (Johns et al., 2000). ...
... Using recycled PET that contains 96.3% less BP (Silano et al., 2020) could reduce the entry of BPs into the environment via leaching from plastics. Improvements in the manufacturing process of PVC also promise less leaching (Huang et al., 2016). According to the "benign by design" model, substantial reductions can be achieved by using other types of organic UV filters, which are more easily decomposed and less toxic to aquatic life. ...
Benzophenone-type UV filters (BPs) represent a very diverse group of chemicals that are used across a range of industrial sectors around the world. They are found within different environmental compartments (e.g. surface water, groundwater, wastewater, sediments and biota) at concentrations ranging from ng/L to mg/L. Some are known as endocrine disruptors and are currently within the scope of international regulations. A structural alert for high potential of endocrine disrupting activity was assigned to 11 BP derivatives. Due to the widespread use, distribution and disruptive effects of some BPs, knowledge of their elimination pathways is required. This review demonstrates that biodegradation and photolytic decomposition are the major elimination processes for BP-type UV filters in the environment. Under aerobic conditions, transformation pathways have only been reported for BP, BP-3 and BP-4, which are also the most common derivatives. Primary biodegradation mainly results in the formation of hydroxylated BPs, which exhibit a structure-related increase in endocrine activity when compared to their parent substances. By combining 76 literature-based transformation products (TPs) with in silico results relating to their receptor activity, it is demonstrated that 32 TPs may retain activity and that further knowledge of the degradation of BPs in the environment is needed.
... They are more efficien compared with the additives containing benzotriazole. Benzophenone-based UV absor ers have unique properties such as a low cost, low toxicity, and good resistance to wat and acids [53]. These additives have unique UV absorbance characteristics. ...
... They are more efficient compared with the additives containing benzotriazole. Benzophenone-based UV absorbers have unique properties such as a low cost, low toxicity, and good resistance to water and acids [53]. Triazoles have high molar extinction coefficients (5 × 106 cm −1 M -1 ) and absorb the most destructive wavelength of light (280-370 nm), which is highly involved in polymer degradation. ...
The photooxidative degradation process of plastics caused by ultraviolet irradiation leads to bond breaking, crosslinking, the elimination of volatiles, formation of free radicals, and decreases in weight and molecular weight. Photodegradation deteriorates both the mechanical and physical properties of plastics and affects their predicted life use, in particular for applications in harsh environments. Plastics have many benefits, while on the other hand, they have numerous disadvantages, such as photodegradation and photooxidation in harsh environments and the release of toxic substances due to the leaching of some components, which have a negative effect on living organisms. Therefore, attention is paid to the design and use of safe, plastic, ultraviolet stabilizers that do not pose a danger to the environment if released. Plastic ultraviolet photostabilizers act as efficient light screeners (absorbers or pigments), excited-state deactivators (quenchers), hydroperoxide decomposers, and radical scavengers. Ultraviolet absorbers are cheap to produce, can be used in low concentrations, mix well with polymers to produce a homogenous matrix, and do not alter the color of polymers. Recently, polyphosphates, Schiff bases, and organometallic complexes were synthesized and used as potential ultraviolet absorbers for polymeric materials. They reduced the damage caused by accelerated and natural ultraviolet aging, which was confirmed by inspecting the surface morphology of irradiated polymeric films. For example, atomic force microscopy revealed that the roughness factor of polymers’ irradiated surfaces was improved significantly in the presence of ultraviolet absorbers. In addition, the investigation of the surface of irradiated polymers using scanning electron microscopy showed a high degree of homogeneity and the appearance of pores that were different in size and shape. The current work surveys for the first time the use of newly synthesized, ultraviolet absorbers as additives to enhance the photostability of polymeric materials and, in particular, polyvinyl chloride and polystyrene, based mainly on our own recent work in the field.
... Poly vinyl chloride (PVC) has special mechanical and physical properties, with chemical formula (CH2-CHCl)n, it is colorless rigid material. The PVC relatively has high density and low softening point and likewise, it is mostly used as a thermoplastic material [1]. It is commercially produced by a number of techniques but generally emulsion, suspension, solution and bulk polymerization of vinyl chloride. ...
In this work, the photo-stabilization of poly (vinyl chloride) was studied using new compounds such as Schiff base stabilizers derived from heterocyclic compounds, with symbols [I1-I4] which were used as additives to prevent the PVC photodegradation. Many samples have been prepared as films for this purpose by adding the additives to poly (vinyl chloride) with varying weight percentages of additives and thicknesses. The photostabilization activities for these new compounds were measured by detecting the carbonyl group with irradiation time (the absorption band of carbonyl was determined at 1724-1772 cm-1). FT-IR spectra PERKIN ELMER SPEACTUM-65, JASCO used to determine the absorption spectra of PVC films, also the viscosity average molecular weight (̅), the average number of chain scission (S), and the degree of deterioration (α) were studied. Scanning Electron Microscope (SEM) and light microscope are also used to test the polymeric films surface. We discovered that in the existence of additives, the rate of photostabilization follows the trend:-I4 > I3 > I1 > I2 > PVC According to the experimental results, a UV absorption peroxide decomposer has been proposed for mechanisms.
... They are more efficien compared with the additives containing benzotriazole. Benzophenone-based UV absor ers have unique properties such as a low cost, low toxicity, and good resistance to wat and acids [53]. These additives have unique UV absorbance characteristics. ...
... They are more efficient compared with the additives containing benzotriazole. Benzophenone-based UV absorbers have unique properties such as a low cost, low toxicity, and good resistance to water and acids [53]. Triazoles have high molar extinction coefficients (5 × 106 cm −1 M -1 ) and absorb the most destructive wavelength of light (280-370 nm), which is highly involved in polymer degradation. ...
The photooxidative degradation process of plastics caused by ultraviolet irradiation leads to bond breaking, crosslinking, the elimination of volatiles, formation of free radicals, and decreases in weight and molecular weight. Photodegradation deteriorates both the mechanical and physical properties of plastics and affects their predicted life use, in particular for applications in harsh environments. Plastics have many benefits, while on the other hand, they have numerous disadvantages, such as photodegradation and photooxidation in harsh environments and the release of toxic substances due to the leaching of some components, which have a negative effect on living organisms. Therefore, attention is paid to the design and use of safe, plastic, ultraviolet stabilizers that do not pose a danger to the environment if released. Plastic ultraviolet photostabilizers act as efficient light screeners (absorbers or pigments), excited-state deactivators (quenchers), hydroperoxide decomposers, and radical scavengers. Ultraviolet absorbers are cheap to produce, can be used in low concentrations, mix well with polymers to produce a homogenous matrix, and do not alter the color of polymers. Recently, polyphosphates, Schiff bases, and organometallic complexes were synthesized and used as potential ultraviolet absorbers for polymeric materials. They reduced the damage caused by accelerated and natural ultraviolet aging, which was confirmed by inspecting the surface morphology of irradiated polymeric films. For example, atomic force microscopy revealed that the roughness factor of polymers’ irradiated surfaces was improved significantly in the presence of ultraviolet absorbers. In addition, the investigation of the surface of irradiated polymers using scanning electron microscopy showed a high degree of homogeneity and the appearance of pores that were different in size and shape. The current work surveys for the first time the use of newly synthesized, ultraviolet absorbers as additives to enhance the photostability of polymeric materials and, in particular, polyvinyl chloride and polystyrene, based mainly on our own recent work in the field.
