Polymeric Compounds Research Articles

Analyzing trade-off issues in synthesis of magnetic polymer compounds through theoretical investigation

Incorporating magnetic species, magnetic functional groups or additives, into polymer hosts is an effective method for synthesizing magnetic polymers. Polymers can gain magnetic moments not solely through magnetic coupling but also via the induction of Coulombic excitation. Attachment of the magnetic side-groups to the polymer backbone increases orbital localization in repeat units. This will bring two competing effects. The orbital localization will increase the intra-site Coulomb interaction, which increases magnetic moments in repeat units. Oppositely, the orbital localization also increases the energy splitting between orbitals on the polymer backbone and on side-groups, suppressing thus the magnetic moments of repeat units. However, a preference for low-spin states in the polymer units emerges when a substantial split in orbital energy occurs due to a strong coupling, consequently suppressing the magnetic moment. On the contrary, a minimal split in orbital energy within the polymer units can readily induce a high-spin state and generate a magnetic moment. However, in such cases, the Coulomb interaction triggered by the interconnected magnetic moieties might be too weak to produce a magnetic moment in the polymer. To explore this trade-off, we have proposed a theoretical two-level model aimed at elucidating the decision-making process of experimentalists during the synthesis of magnetic polymers. We also found that the dimerization of the polymer backbone together with the phonon dependence of spin–spin interaction between near-neighbor repeat units increases magnetic moments. As the magnetic responses arising from Coulombic interactions in polymers are intricately linked to carrier density, properties of the magnetic polymers acting as an active layer of a field-effect transistor can be tuned by the gate field, which controls the charge carrier density in the transistor transport channel.

INFLUENCE OF EXTERNAL FACTORS ON BINARY SYSTEMS DURING RAFT POLYMERIZATION

The article discusses the method of radical copolymerization as an effective way to obtain new polymer compounds with practically valuable properties. This method is based on the free radical mechanism, in which the sequential addition of molecules of an unsaturated monomeric compound to a growing macroradical occurs. Due to the relative simplicity of this method, it makes it possible to produce a large number of polymers for various purposes on an industrial scale. Unsaturated polyesters of various compositions and molecular weights, which can significantly affect the properties of the final products, are considered promising coreagents capable of entering into radical copolymerization reactions with vinyl monomers. The article discusses the results of studies of polymer gels obtained on the basis of unsaturated carboxylic acids. The author refers to previous studies, showing that such gels have high sorption capacity, while the starting material does not have similar properties. The following describes the structure analysis of p-PGFPh copolymers with these acids, where important characteristics such as the presence of ionized units in vinyl monomers are discussed. The significance of these studies for the creation of materials with the necessary properties of sorption and interaction with other substances. Study of the influence of environmental pH on the behavior of copolymers based on polypropylene glycol fumarate phthalate with acrylic and methacrylic acids. The equilibrium degree of swelling of the studied copolymers in aqueous solutions at different temperatures was also determined by the gravimetric method. In general, analysis of the swelling curve when varying the acidity/alkalinity of the external solution indicates that the gels we synthesized are polyelectrolytes; analysis of the curve when exposed to temperature, the resulting copolymers are thermosensitive. Thus, the main idea of the article is the importance of using unsaturated carboxylic acids to create polymer gels with high sorption capacity and emphasizes the importance of analyzing the structure of such materials to understand their properties and application possibilities.

Discrete molecular weight strategy modulates hydrogen bonding‐induced crystallization and chain orientation for melt‐spun high‐strength polyamide fibers

AbstractHydrogen bonding is the prerequisite for polyamide fibers to have better stress–strain behavior. It affects the crystal structure of polyamide fibers, such as orientation and periodic arrangement. To illustrate the effect of intermolecular hydrogen bonding on fiber orientation structure and macroscopic mechanical properties, this work uses conventional polyamide resin doped with high molecular weight components to construct polymer compounds with discrete distribution characteristics. By analyzing the changes in intermolecular hydrogen bonds, melt rheological properties, non‐isothermal crystallization behaviors, the impact of hydrogen bonds on the crystal structure and orientation structure and thus on the fiber strength was clarified. The doping of high molecular weight components can make the compound form more hydrogen bonds and inhibit the relaxation of molecular chains through entanglement, thereby promoting melt non‐isothermal crystallization process and increasing complex viscosity η* and storage mode G'. 1D and 2D wide‐angle and small‐angle X‐ray scattering show that doping components reduce crystal size of α1(200) and α2(002, 202) planes from 4.19 to 3.47 nm and 5.88 to 4.96 nm, resulting in a denser long‐period structure. Through the strategy of this work, polyamide 6 fibers' tensile strength is effectively improved by18%, and the mechanical properties are significantly improved.Highlights High‐strength polyamide compound fibers were prepared. Discretely distributed compounds are achieved. Discretely distributed molecular weight enabled hydrogen bonding regulation. Hydrogen bonding‐induced compound fiber crystal structure. Multiple external fields induced crystallization and orientation structures.

Synthesis and characterization of flame retardant unsaturated polyester-allyloxysilane resin for wood coatings

Fireproof coatings are the simplest, most efficient, and oldest method for protecting a wide range of flammable products, such as wood. Furthermore, surface ignition is the initial phase, so surface protection is essential to reduce fire propagation. Furthermore, delaying the spread of flames can help to save someone when a fire starts. This project synthesized flame-resistant resin starting from tetraallyloxysilane monomer as a halogen-free monomer, an intrinsic flame retardant co-curing agent. The following step synthesized polyester resin using terephthalic acid as a heat-resistant resin. Unsaturated polyester was used by bulk radical polymerization. FT-IR and 1H-NMR analysis showed the successful synthesis of the desired monomer and polymeric compound. The thermal degradation and flame retardancy of pure unsaturated polyester resin (UPE) and allyloxysilane-unsaturated polyester (AUPE) were investigated by thermogravimetric analysis (TGA/DTG/DSC). The burning test and the thermal stability of the coating layers were evaluated using standard UL 94. Physical properties of resins were evaluated using Heat Deflection Temp tests (HDT) ISO 75-A, ASTM 648, Hardness ASTM D2583, Volumetric shrinkage ASTM 3521, and Water absorption ASTM D570. The results of the tests show the successful synthesis and their flame retardant properties.

Characterization of the Solution Properties of Sodium Dodecylsulphate Containing Alkaline–Surfactant–Polymer Flooding Media

Alkaline–surfactant–polymer (ASP) flooding by means of which alkali additives, surfactant and polymer are inserted as the same slug is one of the most favourable worldwide focuses of Chemical Enhanced Oil Recovery (cEOR) research and field trials, due to the individual synergy of the three chemical components. To develop efficient oil recovery chemicals, it is essential to fully understand the mechanism behind ASP flooding. Nonetheless, there are hardly any studies reporting a systematic characterization of the ASP process. Thus, the present paper focuses on modelling this process in a laboratory by the use of an anionic surfactant—sodium dodecyl sulphate (SDS) in alkaline–polymer media—which is composed of a commercial water-soluble polymer (Flopaam AN125SH®, SNF Floerger, Andrézieux-Bouthéon, France) and alkali compounds (NaOH and Na2CO3). The samples were characterized using rheometry, dynamic light scattering (DLS), infrared spectroscopy (IR) and measurement of inferfacial tension (IFT) between the samples and rapeseed oil. In accordance with the experimental results, surprisingly lower IFT values were recorded between the alkaline–polymer solutions and rapeseed oil than the samples which contained SDS. Increasing polymer and sodium chloride concentration caused a decrease (from 0.591 mN/m to 0.0486 mN/m) in IFT between the surfactant containing samples and rapeseed oil. The IR measurements confirmed that the surfactant was not detected in the oil phase in the absence of NaOH and Na2CO3. The effects of SDS on the viscosity of the mixtures were also investigated, as viscosity is a considerably important parameter in processes using polymers.

Unique Use of Dibromo-L-Tyrosine Ligand in Building of Cu(II) Coordination Polymer-Experimental and Theoretical Investigations.

Although the crystals of coordination polymer {[CuCl(μ-O,O'-L-Br2Tyr)]}n (1) (L-Br2Tyr = 3,5-dibromo-L-tyrosine) were formed under basic conditions, crystallographic studies revealed that the OH group of the ligand remained protonated. Two adjacent [CuCl(L-Br2Tyr)] monomers, bridged by the carboxylate group of the ligand in the syn-anti bidentate bridging mode, are differently oriented to form a polymeric chain; this specific bridging was detected also by FT-IR and EPR spectroscopy. Each Cu(II) ion in polymeric compound 1 is coordinated in the xy plane by the amino nitrogen and carboxyl oxygen of the parent ligand and the oxygen of the carboxyl group from the symmetry related ligand of the adjacent [Cu(L-Br2Tyr)Cl] monomer, as well as an independent chlorine ion. In addition, the Cu(II) ion in the polymer chain participates in long-distance intermolecular contacts with the oxygen and bromine atoms of the ligands located in the adjacent chains; these intramolecular contacts were also supported by NCI and NBO quantum chemical calculations and Hirshfeld surface analysis. The resulting elongated octahedral geometry based on the [CuCl(L-Br2Tyr)] monomer has a lower than axial symmetry, which is also reflected in the symmetry of the calculated molecular EPR g tensor. Consequently, the components of the d-d band obtained by analysis of the NIR-VIS-UV spectrum were assigned to the corresponding electronic transitions.

Synthesis of carbazole-based Schiff base and fluorescence turn on sensor sensitive to Cr3+ ion: Oxidative and electrochemical polymerization and investigation of electrochromic properties

In this study, a Schiff base monomer (ECBA) was initially synthesized from condensation reaction of 3-amino 9-ethyl carbazole (AEC) with 2,4-dihydroxy benzaldehyde (DHBA). Then, its poly(ECBA-1) polymer was synthesized via oxidative polycondensation in methanol/THF (v/v:4/1) medium by NaOCl oxidant. The structures of the obtained monomer and poly(ECBA-1) were confirmed by 1H NMR, 13C NMR and FT-IR. The optical and electrochemical properties of compounds were examined by UV–Vis, fluorescence spectroscopy and cyclic voltammetry (CV) measurements, respectively. The Highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels and electrochemical (E’g) and optical band gap (Eg) values were determined for monomer and polymer compounds by cyclic voltammetry and UV–Vis spectrophotometry. Thermal stabilities of the monomer and poly(ECBA-1) were determined from thermogravimetric-differential thermal analysis (TG-DTA) measurements. The molecular weight distribution and Tg temperature of the poly(ECBA-1) were determined by gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) measurements, respectively. The surface morphologies of the synthesized polymers and copolymer were investigated by scanning electron microscopy (SEM). By fluorescence titration, ECBA was found to be selective towards Cr3+ ion among Ag+, K+, Mn2+, Hg2+, Co2+, Ca2+, Ni2+, Cu2+, Zn2+, Pb2+, Cd2+, Fe3+, Cr3+, Cr+6 ions. The selectivity of Cr3+ion was confirmed by the absence of interference from other competitive cationic species. The limit of detection (LOD) and binding constant (Ka) values for the fluorescent probe were calculated as 6.07 x 10-7 M and 1.25 x 104 M−1, respectively. In addition, homopolymer and copolymer synthesis was carried out on Pet ITO selected as working electrode via electropolymerization method by the synthesized ECBA monomer. Homopolymer synthesis was carried out by Cyclic Voltammetry (CV) method and copolymer synthesis was carried out by batch electrolysis method using EDOT with ECBA monomer. Spectroelectrochemical measurements were taken to investigate the electrochromic properties of the prepared homopolymer poly(ECBA-2) and copolymer (Poly(ECBA-co-EDOT)). The copolymer was found to have a more stable structure than the homopolymer.

Improved Tribological Performance of a Polybutylene Terephthalate Hybrid Composite by Adding a Siloxane-Based Internal Lubricant

To mitigate the environmental hazards aroused by fossil-based lubricants, the development of eco-friendly internal lubricants is imperative. Siloxane-based internal lubricants, widely applied as plasticizers in polymeric compounds, are a promising option. However, their impacts on the tribological properties of polymeric tribocomponents are still unclarified. Therefore, in the current study, a siloxane-based internal lubricant with the product name ‘EverGlide MB 1550 (EG)’ was dispersed into a polybutylene terephthalate (PBT)-based tribological composite to investigate whether the tribological properties of the composite can be optimized. A block-on-ring (BOR) test configuration was used for this purpose. It was found that the addition of EG to the composite significantly improved the tribological behavior; the improvement was particularly significant under lower load conditions (pv-product ≤ 2 MPa∙m/s). Compared to the reference PBT composite, the addition of EG reduced the friction coefficient (COF) by about 30% and the specific wear rate by about 14%. An accompanying surface analytical investigation using photoelectron spectroscopy to elucidate the effective mechanisms at the molecular level showed the availability of tribologically effective and free EG after its addition to the composite in the relevant tribocontact.

Effect of storage condition on the viability of sago effluents as carbon source in fermentation medium for bioethanol production

In Sarawak, Malaysia, approximately 237 tons/day of sago effluent is commonly discharged into nearby river due to the sago starch extraction process. Due to the high concentration of polymeric compounds, particularly starch, in sago wastewater, which petrifies easily, this condition severely pollutes the environment in the affected area. This study was conducted to determine the viability of using sago effluent as a carbon source and fermentation medium for bioethanol production which indirectly help to minimize the environmental impact as well as the economics of the sago industry. The sago effluent obtained from the local sago mill was analysed for starch content and pH profile while stored at room and cold (4°C) temperature facility. Enzymatic hydrolysis was conducted to convert the residual starch into glucose as carbon source for bioethanol fermentation. Fresh sago effluent can be stored for up to 5 days in cold temperature where the starch content remains constant. The highest starch concentration in sago effluent was 61.33 g/L, in which 50.57 g/L glucose was obtained through the enzymatic hydrolysis process. Hence 82.5% of the starch to glucose conversion yield is revealed. Then, the sago effluent hydrolysate which acts as a carbon source as well as a fermentation medium able to generate 23.14 g/L of bioethanol, displays a 91% theoretical yield of glucose to ethanol. In conclusion, the utilization of sago wastewater as feasible alternative to cheap and locally available and sustainable source of raw materials to produce bioethanol.

Computational Codes for Fast Neutrons and Gamma Ray Interactions Coefficients in Different Material

In this research, many materials used as shields against ionizing radiation (neutrons and gamma rays) were studied. Seven glass systems compounds and five polymeric compounds were used to test their effectiveness in attenuating fast neutrons. These compounds are (S1-S7) as shown in table (1) and polymeric compounds as shown in table (3), many attenuation coefficients for these compounds were calculated through the use of a computer program called (SAZ) written in the Python programming language, which is used to calculate a number of basic parameters based on certain semi-empirical equations. The results showed that the sample (S7) and C9H9O is the best glass system compound and polymeric compound for neutrons attenuation, because they have a largest value of ΣR. Also, a number of Eco-friendly metallic compounds as shown in table (2) were used, to test them in shielding against gamma rays. The mass attenuation coefficient was calculated through the NIST-XCOM program for a range of energies starting from 59.53 keV up to 1 GeV. These compounds differed in their ability to attenuate gamma rays, as the results showed that the best studied compound against gamma rays was the PbS compound because it contains the Lead element, which has a largest atomic number.

Process Optimization of the Morphological Properties of Epoxy Resin Molding Compounds Using Response Surface Design.

An epoxy compound's polymer structure can be characterized by the glass transition temperature (Tg) which is often seen as the primary morphological characteristic. Determining the Tg after manufacturing thermoset-molded parts is an important objective in material characterization. To characterize quantitatively the dependence of Tg on the degree of cure, the DiBenedetto equation is usually used. Monitoring polymer network formation during molding processes is therefore one of the most challenging tasks in polymer processing and can be achieved using dielectric analysis (DEA). In this study, the morphological properties of an epoxy resin-based molding compounds (EMC) were optimized for the molding process using response surface analysis. Processing parameters such as curing temperature, curing time, and injection rate were investigated according to a DoE strategy and analyzed as the main factors affecting Tg as well as the degree of cure. A new method to measure the Tg at a certain degree of cure was developed based on warpage analysis. The degree of cure was determined inline via dielectric analysis (DEA) and offline using differential scanning calorimetry (DSC). The results were used as the response in the DoE models. The use of the DiBenedetto equation to refine the response characteristics for a wide range of process parameters has significantly improved the quality of response surface models based on the DoE approach.

Nanoparticles based on polyferylic and polygentisic acids as new carriers of anticancer drugs

Lignin polymers and their derivatives are actively used in various fields of biomedicine to create biocompatible materials, as medications, and to form nanoparticles. However, natural polymeric compounds derived from plant materials or monomers are defined as a mixture of compounds having a high heterogeneity in chemical structure, which greatly complicates the determination of their biological activity. This paper describes a new method of controlled synthesis using the enzyme laccase, which can be applied to obtain polymers with a specific structure. Based on enzymatically synthesized lignin-like polymers from ferulic and gentisiс phenolic monomers, nanoparticles with stable properties under physiological conditions were formed. The nanoparticles can differ in morphology from globular to fibrillar structures, depending on monomers used in the enzymatic reaction and the method of their formation. Nanoparticles obtained from lignin-like polymers of ferulic and gentisic acids can be loaded with low molecular weight hydrophobic compounds, including the anticancer drug doxorubicin. It has been shown that polyferulic nanoparticles are actively penetrate in tumor cells growing both in a monolayer culture and as part of spheroids, and, compared with a free compound, doxorubicin in the composition of nanoparticles has a greater cytotoxic effect on breast cancer cells. These data indicate the possibility of effective use of these carriers as passive targeted drug delivery in the treatment of tumors.

A Review on Coronary Stents: With Polymers and without Polymers

Polymers have many uses in cardiology, such as coating matrices for drug-eluting stents and stent platforms (scaffolds) during coronary vascular intervention. Current research focuses on biodegradable polymers rather than permanent polymers. Their use may help to lessen undesirable events such as in-stent restenosis, late stent-thrombosis, and hypersensitivity reactions since they disintegrate once their purpose is served. This paper discusses factors affecting tissue and blood cell functions that should be taken into account when assessing the biocompatibility of stent polymers to improve physiologically suitable 3 Polymers are frequently used in cardiology, particularly in coronary vascular intervention, as coating matrices for drug-eluting stents and stent platforms (scaffolds). In addition to permanent polymers, biodegradable polymers are the subject of current study. Since they break down once their function is completed, using them may help prevent unfavorable outcomes such as in-stent restenosis, late stent thrombosis, and hypersensitivity reactions. This review discusses aspects of blood cell and tissue operations that should be taken into account to evaluate the biological compatibility of stent polymer compounds to improve physiologically relevant features after examining recent literature on polymers used in applications related to cardiology. The shape, difference, motion, and future of vascular cells can all be significantly influenced by the characteristics of the supporting material that they are grown. Lastly, a summary of techniques for measuring these parameters in a physiological setting will be provided.

Necessity and possible promising directions for creating artificial choledoch duct (literature review)

This review is devoted to the prospect of creating an artificial choledoch duct in case of its intraoperative injuries. Currently, there is no consensus on the optimal tactics of reconstructive surgical interventions, determining indications for the formation of biliodigestive anastomoses and transhepatic drainage of the biliary tract. The quality patients’ life after reconstruction in low mortality rate in this type of surgery decreases due to recurrent cholangitis, which in the future leads to liver abscesses and cirrhosis. The first attempts of prosthetics of the common bile duct were associated with the first use of stents in surgical practice. The second stage in the study of the reconstruction of the common bile duct were attempts to use stents and patches from transplants of subcutaneous veins, urethra, vagina of the rectus abdominis, and small intestine. The third stage in the development of this direction is using stents made with fibers of biodegradable polymer compounds. There several advantages of using biodegradable stents. Firstly, they are completely metabolized in the body and perform a skeleton function. Secondly, it is possible to use multilayer structures by means of cellular technologies that ensure the conformitythis of the model with the structures of the common bile duct. A stent from biodegradable material can be used with radiopaque dye and medications, for example, antibiotics to prevent cholangitis, or drugs supressing enhanced formation of fibrous tissue to prevent strictures.

The Sensitivity of Structure to Ionic Radius and Reaction Stoichiometry: A Crystallographic Study of Metal Coordination and Hydrogen Bonding in Barbiturate Complexes of All Five Alkali Metals Li-Cs.

A systematic study has been conducted on barbiturate complexes of all five alkali metals, Li-Cs, prepared from metal carbonates or hydroxides in an aqueous solution without other potential ligands present, varying the stoichiometric ratio of metal ion to barbituric acid (BAH). Eight polymeric coordination compounds (two each for Na, K, and Rb and one each for Li and Cs) have been characterised by single-crystal X-ray diffraction. All contain some combination of barbiturate anion BA- (necessarily in a 1:1 ratio with the metal cation M+), barbituric acid, and water. All organic species and water molecules are coordinated to the metal centres via oxygen atoms as either terminal or bridging ligands. Coordination numbers range from 4 (for the Li complex) to 8 (for the Cs complex). Extensive hydrogen bonding plays a significant role in all the crystal structures, almost all of which include pairs of N-H···O hydrogen bonds linking BA- and/or BAH components into ribbons extending in one dimension. Factors influencing the structure adopted by each compound include cation size and reaction stoichiometry as well as hydrogen bonding.

Examining the bending test properties of bio-composites strengthened with fibers through a combination of experimental and modeling approaches

This study explores the relationship between natural fiber filling density (10%, 15%, 25%) and its impact on the bending properties of polymer compounds reinforced with Diss, Sisal and Luffa fibers. Using advanced techniques like fiber analysis and Fourier transform infrared spectrometry (FTIR), the research reveals that a 25% filling density results in the highest stress values (25.61 MPa, 22.21 MPa and 20.88 MPa) for Diss, Sisal and Luffa compounds, respectively, fostering robust bonds in Diss-reinforced polymers. The Artificial Neural Network (ANN) model demonstrates superior predictive capability with correlation coefficients exceeding 0.99 for stress and displacement, outperforming Response Surface Methodology (RSM). Analysis of Variance (ANOVA) underscores the impact of sample section parameters and fiber rate on stress, establishing the significance of type parameters and fiber rate on displacement. This integration of ANN and RSM represents a paradigm shift in predicting bending mechanical properties, advancing our understanding of composite materials for innovative applications.

Effect of Cu(II) compound containing dipicolinic acid on DNA damage: a study of antiproliferative activity and DNA interaction properties by spectroscopic, molecular docking and molecular dynamics approaches

A polymeric compound formulized as [Cu(µ-dipic)2{Na2(µ-H2O)4]n.2nH2O (I), where dipic is 2,6-pyridine dicarboxylic acid (dipicolinic acid, H2dipic), was synthesized by sonochemical irradiation. The initial in-vitro cytotoxic activity of this complex compared with renowned anticancer drugs like cisplatin, versus HCT116 colon cell lines, shows promising results. This study investigated the interaction mode between compound (I) and calf-thymus DNA utilizing a range of analytical techniques including spectrophotometry, fluorimetry, partition coefficient analysis, viscometry, gel electrophoresis and molecular docking technique. The results obtained from experimental methods reveal complex (I) could bind to CT-DNA via hydrogen bonding and van der Waals forces and the theoretical methods support it. Also, complex (I) indicates nuclease activity in the attendance of H2O2 and can act as an artificial nuclease to cleave DNA with high efficiency. Communicated by Ramaswamy H. Sarma

Laccase-Mediated Oxidation of Phenolic Compounds from Wine Lees Extract towards the Synthesis of Polymers with Potential Applications in Food Packaging.

Laccase from Trametes versicolor was applied to produce phenolic polymeric compounds with enhanced properties, using a wine lees extract as the phenolic source. The influence of the incubation time on the progress of the enzymatic oxidation and the yield of the formed polymers was examined. The polymerization process and the properties of the polymeric products were evaluated with a variety of techniques, such as high-pressure liquid chromatography (HPLC) and gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The enzymatic polymerization reaction resulted in an 82% reduction in the free phenolic compounds of the extract. The polymeric product recovery (up to 25.7%) and the molecular weight of the polymer depended on the incubation time of the reaction. The produced phenolic polymers exhibited high antioxidant activity, depending on the enzymatic oxidation reaction time, with the phenolic polymer formed after one hour of enzymatic reaction exhibiting the highest antioxidant activity (133.75 and 164.77 μg TE mg-1 polymer) towards the ABTS and DPPH free radicals, respectively. The higher thermal stability of the polymeric products compared to the wine lees phenolic extract was confirmed with TGA and DSC analyses. Finally, the formed phenolic polymeric products were incorporated into chitosan films, providing them with increased antioxidant activity without affecting the films' cohesion.

LyondellBasell launches Petrothene T3XL7420: a polymer compound for optimized manufacturing

On January 23, 2024, LyondellBasell (LYB) announced the release of a cross-linkable, all-in-one flame-retardant compound, Petrothene T3XL7420, which is expected to deliver considerable cost savings while streamlining manufacturing processes. This new product offering is also claimed to improve the quality of end products for wire producers in the automotive and appliance industries. Based on customer demand and industry need, LyondellBasell designed this innovative compound to address the need to optimize production line speeds and enhance manufacturing efficiency.

ASSESSMENT OF THE TECHNOLOGICAL CAPABILITIES OF MODERN CHEMICAL MATERIALS FOR LIQUID FINISHING OF LEATHER

Natural leather is a by-product of the meat industry, which turns into a valuable product that has high strength, stability, comfort, breathability and is considered one of the best products of the circular economy. In addition, less materials from non-renewable sources are used in leather production than in other industries, recycling of waste is practiced, which contributes to the protection of the environment and sustainable development of society. The choice of processing method, type of equipment and chemical materials is of great importance for the quality of leather and the ecological imperative of its manufacturing technology. At the same time, despite the progress of modern chemical technology, the leather industry constantly needs to find and introduce new, more effective means, which would not only be stable in their properties, available and compatible with the components of the «collagen-chemical material» system, but would also contribute the formation of this system in the direction of creating quality products while reducing the harmful load on the environment. The results of previous studies indicate the prospects of modified liquor materials and polymer compounds. Taking into account the above, the technological capabilities of modern commercial chemical materials - modified fats of various origins and acrylic polymer - were analyzed by using them in the liquid decoration of semi-finished Wet-blue half skin. Using the methods of organoleptic assessment, chemical analysis, physico-mechanical tests and microscopy, the advantages of these materials compared to those known during retanning-filling and liquoring have been established. The improvement of the indicators of the content of unbound fat in the leather, the limit of tensile strength and elongation at a stress of 10 MPa was revealed. Good elastic-plastic properties and no difference between the strength of the test skins as a whole and their front layer indicate a more even distribution of materials in the structure of the dermis. This correlates with the results of microscopic studies and allows predicting an increase in area yield, that is, a more rational use of scarce leather raw materials. The results of the work will be used in further studies devoted to the optimization of the parameters of the technology of liquid finishing of natural leather.