Unsaturated Groups Research Articles

Adsorption and mechanism study for phenol removal by 10% CO2 activated bio-char after acid or alkali pretreatment

The development of an efficient bio-char used to remove phenol from wastewater holds great importance for environmental protection. In this work, wheat straw bio-char (BC) was acid-washed by HF and activated at 900 °C with 10% CO2 to obtain bio-char (B-Ⅲ-0.1D900). Adsorption experiments revealed that B-Ⅲ-0.1D900 achieved a remarkable phenol removal efficiency of 90% within 40 min. Despite its relatively low specific surface area of 492.60 m2/g, it exhibited a high maximum adsorption capacity of 471.16 mg/g. Furthermore, B-Ⅲ-0.1D900 demonstrated a good regeneration capacity for at least three cycles (90.71%, 87.54%, 84.36%). It has been discovered that HF washing, which removes AAEM and exposes unsaturated functional groups, constitutes one of the essential prerequisites for enhancing CO2 activation efficiency at high temperatures. After 10% CO2 activation, the mesoporous structure exhibited substantial development, facilitating enhanced phenol infiltration into the pores when compared to untreated BC. The increased branching of the bio-char culminated in a more complete aromatic system, which enhances the π-π forces between the bio-char and the phenol. The presence of tertiary alcohol structure enhances the hydrogen bonding forces, thereby promoting intermolecular multilayer adsorption of phenol. With the combination of various forces, B-Ⅲ-0.1D900 has a good removal capacity for phenol. This work provides valuable insights into the adsorption of organic pollutants using activated bio-char.

Functional polythioamides derived from thiocarbonyl fluoride.

Polythioamide is a unique type of sulfur-containing polymers with advanced functionalities. Nonetheless, the prevailing synthetic methods, reliant upon elemental sulfur, tend to react readily with unsaturated functional groups, thereby limiting the scope of eligible substrates. Inspired by the highly efficient sulfur-fluoride exchange (SuFEx) polymerization through discrete hubs, we present herein a pioneering and versatile approach to the synthesis of polythioamides from diboronic acids, secondary diamines, and thiocarbonyl fluoride as the central connective hub.Well-defined structures, including previously inaccessible unsaturated substrates, were realized. These newly devised polythioamides can efficiently and selectively bind to metal ions and were applied in precious metal recovery. Further development results in PdII-crosslinked single-chain nanoparticles serving as recyclable homogeneous catalysts, demonstrating the vast potential of these unprecedented polythioamides. We anticipate that thiocarbonyl fluoride could emerge as a potent hub for facilitating the intricate synthesis of sulfur-containing polymers.

Functional Polythioamides Derived from Thiocarbonyl Fluoride**

AbstractPolythioamide is a unique type of sulfur‐containing polymer with advanced functionalities. Nonetheless, the elemental sulfur commonly used in their synthesis tends to react readily with unsaturated functional groups, thereby limiting the scope of eligible substrates. Inspired by the highly efficient sulfur‐fluoride exchange (SuFEx) polymerization through discrete hubs, we present herein a pioneering and versatile approach to the synthesis of polythioamides from diboronic acids, secondary diamines, and thiocarbonyl fluoride as the central connective hub. Well‐defined structures, including previously inaccessible unsaturated substrates, were realized. These newly devised polythioamides can efficiently and selectively bind to metal ions and were applied in precious‐metal recovery. Further development resulted in PdII‐crosslinked single‐chain nanoparticles serving as recyclable homogeneous catalysts, thus demonstrating the vast potential of these unprecedented polythioamides. We anticipate that thiocarbonyl fluoride could emerge as a potent hub for facilitating the intricate synthesis of sulfur‐containing polymers.

Bismaleimide resin modified by a propargyl substituted aromatic amine with ultrahigh glass transition temperature, thermomechanical stability and intrinsic flame retardancy

N, N, N′, N′ -tetrapropargyl-p, p’-diaminodiphenylmethane (TPDDM) was synthesized and used to prepolymerized with 4,4′-bismaleimide diphenylmethane (BDM) in molten state to obtain a new TPDDM modified bismaleimide (BTP) resin by addition reaction. The BTP resin displays a good solubility and meltability with process window of 90 °C. The self-polymerization of TPDDM and BDM and further free radical polymerization of the unsaturated groups construct the cross-linked networks to obtain the cured BTP resin. The apparent activation energy of cure reactions for BTP resin decreases slowly with conversion of reactions, and declines clearly with the conversion of above 60%. The residual yield at 600 °C in nitrogen and air of the cured BTP resin are 60.5% and 60%, respectively, and the glass transition temperature of the cured resin can reach 371 °C. The impact and flexural strengths of the cured BTP resin can increase with increase of BDM content in the BTP resin. The flexural strength of the cured BTP resin can reach 60.8 MPa at 300 °C for 30 min, which retains 94% of that at room temperature. The cured BTP resin displays better non-halogen and non‑phosphorus intrinsic flame retardancy based on its excellent thermal stability.

Glucose promoted synthesis of homogeneously embedded black phosphorus carbon composite with enhanced lithium storage performance

Black phosphorus (BP) has attracted extensive attention in high-rate lithium-ion batteries due to its high theoretical capacity and moderate lithiation potential. However, the large volume expansion and the low conductivity of BP nanostructures in the electrochemical cycle have inhibited the rate performance and long-term cycle stability. In this paper, by combining the glucose-assisted ball-milling and carbonization method, a black-phosphorus/carbon (BP@C) composite anodic material is developed, in which the nano-sized BP nanoparticles are homogeneously embedded in the amorphous carbon matrix. Both the phosphorus-oxygen-carbon bonds and the phosphorus-carbon bonds improve the cross-link between BP and the surface-coated carbon matrix. The unique well-embedded structure promotes the cycling stability and the rate performance of BP@C. The composite shows a high discharge specific capacity of about 1881 mAh g−1 at 0.1 A g−1, the specific capacity at 4 A g−1 is about 63% of the low current capacity, and the discharge specific capacity retains 1130 mAh g−1 after 300 charge-discharge cycles at 0.5 A g−1. Moreover, the significant role of the active unsaturated groups for building the well-embedded composite is further revealed. These results indicate that dual regulation of surface coating and structure optimization offers great potential for further optimizing phosphorus-based anode materials.

Proposal of a new mechanism of ammonia on the coking inhibition of n-decane under supercritical conditions

The coking problem of hydrocarbon fuel pyrolysis is the key factor affecting the application of active cooling technology for high-speed aircraft. The purpose of this work is to investigate the coking inhibition performance and coking mechanism of using ammonia as an additive during the thermal cracking. In this study, the pyrolysis and coking characteristics of supercritical n-decane were experimentally studied using an electrically heated tube. ICP-OES (Inductively Coupled Plasma Optical Emission Spectrometer), GC–MS (Gas Chromatograph Mass Spectrometer), SEM (Scanning Electron Microscope), EDS (Energy Dispersive Spectroscopy), TPO (Temperature Programmed Oxidation), and Raman spectroscopy are applied to characterize the anti-coking performance of the additives. The results show that the additive hardly affects the cracking of the fuel under high-temperature conditions, but the coke mass deposited on the inner surface of the tube is significantly reduced, and the coking inhibition rate can reach 80% at 750 °C. The addition of additives reduced the graphitization degree and oxidative activity of the coke. The maximum oxidation temperature of the coke obtained at 750 °C was reduced by 145 °C, and the ID/IG value of the Raman spectroscopy peak-fitting was 3.29. The new mechanism of the effect of additives on the formation of coking precursors and the deposition of coke on the surface of the tube wall is proposed. Ammonia can react with Ni of the inner metal tube and radicals generated by fuel cracking to form a carbonized film, achieving the effect of inhibiting metal catalytic coking. Meanwhile, the amino radicals generated by ammonia dehydrogenation can regulate the coking reaction path by forming a stable p-π conjugate structure with unsaturated radicals. Therefore, the research will contribute to a deeper comprehension of the coking inhibition mechanism and the development of more effective coking inhibitors, providing new technical support for active cooling technologies.

Identification of Fat in Pork Using Fourier Transform Infrared Spectrum and GC-MS

Halal food safety issues receive serious attention. Methods for analyzing contamination of non-halal ingredients, such as lard, must be developed to assist in the halal authentication process for food. This study was conducted to compare the fat profile of pork thighs using FT-IR and GC-MS. The pork is dried in the oven and then extracted using n-hexane. The resulting fat was characterized by FT-IR. Determination of fatty acids was carried out by GC-MS using a derivatization technique. Based on the results of the study showed that the infrared pattern of lard can be identified from the difference in absorption intensity. Pork fat has a higher unsaturated fatty acid content than beef and chicken. Infrared spectra can confirm the presence of -C=C- bonds at 3005, 1745, 1116, 1550, and 722 cm-1. The FTIR data shows that there are larger unsaturated fatty acid groups in pork fat than in beef and chicken fat. This procedure is a non-destructive method that can be carried out quickly, and cheaply, and can be developed into a routine procedure for halal authentication of food. Based on the results of unsaturated fatty acid testing with GC-MS it can show the content of oleic acid (C18:1) contained in pork. The results of mapping the content of free fatty acids in pork can be used to complete halal authentication data easily and quickly.

Fish processing discards extract as an eco-friendly corrosion inhibitor for carbon steel in hydrochloric acid

The objective of this study is to extract amino acids from fish processing discards for the preparation of highly effective and degradable corrosion inhibitors. The composition of fish processing discards extract (FPDE) was characterized by HPLC and FTIR. The results showed that the main components of FPDE are amino acids and contain a large number of unsaturated functional groups. Electrochemical techniques (electrochemical impedance spectroscopy (EIS) and Tafel), surface analysis (XPS and AFM), and molecular dynamics simulations (MDS) were conducted to investigate the corrosion inhibition mechanism of FPDE for carbon steel in 1 mol/L HCl. As shown by electrochemical tests, FPDE exhibits mixed-type corrosion inhibition with a maximum inhibition efficiency of 93.3%. FPDE exhibits excellent corrosion inhibition properties on carbon steel surfaces by forming a high coverage film through chemisorption and physisorption. Indeed, the advantages of remarkable inhibition efficiency and facile extraction methods allow FPDE to become a promising corrosion inhibitor for practical applications.

Roadmap for Postnatal Brain Maturation: Changes in Gray and White Matter Composition during Development Measured by Fourier Transformed Infrared Microspectroscopy.

Key events in postnatal brain development, such as neuronal migration, synaptogenesis, and myelination, shape the adult brain. These events are reflected in changes in gray and white matter (GM and WM) occurring during this period. Therefore, precise knowledge of GM and WM composition in perinatal brain development is crucial to characterizing brain formation as well as the neurodevelopmental disruption observed in diseases such as autism and schizophrenia. In this study, we combined histochemical and immunohistochemical staining with biochemical and biophysical analyses using Fourier transform infrared (IR) microspectroscopy (μFTIR) to better understand the chemical changes during postnatal developmental myelination. For this purpose, we analyzed the GM and WM in the mouse brain and cerebellum (strain C57BL/6) from postnatal day 0 (P0) to day P28 and established presumed correlations between staining and IR data. IR spectra allowed the (i) quantification of lipid and protein content through the CH2/amide I ratio, (ii) determination of chemical characteristics of lipids, such as the presence of unsaturated bonds in the carbonate chain or carbonyls from ester groups in the polar head, and (iii) determination of the protein secondary structure (α-helix and intramolecular β-sheets). The results indicate that the increase in the CH2/amide I ratio calculated from the μFTIR data correlates well with lipid histochemical staining. IR data indicated a change in the lipid composition in WM since carbonyl and unsaturated olefinic groups do not increase when lipids accumulate during myelination. Our correlation analysis between IR data and immunohistochemical staining of myelin-associated proteins revealed that myelin oligodendrocyte protein correlated well with lipid accumulation, while myelin basic protein appeared before lipid modifications, which indicated that myelin-associated proteins and lipid deposition were not synchronic. These events were related to a decrease in the intramolecular β/α protein ratio. Our results indicate that lipids and proteins in WM substantially change their composition due to primary myelination, and according to results obtained from staining, these modifications are better described by lipid histochemical staining than by immunohistochemistry against myelin-related proteins. In conclusion, μFTIR can be a useful technique to study WM during perinatal development and provide detailed information about alterations in the chemical composition related to neurodevelopmental diseases.

A comparative on the thermal decomposition and fire‐extinguishing performance of C5F8 and C5F7Cl

AbstractCompared with fluorinated cycloalkanes and liner olefins, the degradation of chlorofluorocycloolefins is much easier with good environmental friendliness. However, the fire‐extinguishing performance of chlorofluorocycloolefins has been rarely explored. In this study, the fire‐extinguishing performance and working mechanism of octafluorocyclopentene (C5F8) and 1‐chloro‐2,3,3,4,4,5,5‐heptafluorocyclopentene (C5F7Cl) were studied by combined experimental and theoretical approach. It was found that, compared to C5F8, the asymmetry of C5F7Cl agent with the chlorine atom possesses a reduced energy barrier in pyrolysis process and its reaction with OH· radicals. Moreover, chlorine‐containing unsaturated active groups and CF2· radicals generated in C5F7Cl pyrolysis can effectively capture flame radicals. As a result, a relatively low minimum extinguishing concentrations (MECs) for suppressing methane‐air (5.37 vol%) and propane‐air flame (5.93 vol%) is achieved outperforms that of C5F8 (6.73 and 7.74 vol%), even better than reported fluorinated cycloalkanes and chlorofluoroolefins agents. This study shows that chlorofluorocycloolefins are promising Halon substitutes over perfluorocyclic olefins in fire‐extinguishing performance.

Hydride-Free Hydrogenation: Unraveling the Mechanism of Electrocatalytic Alkyne Semihydrogenation by Nickel-Bipyridine Complexes.

Hydrogenation reactions of carbon-carbon unsaturated bonds are central in synthetic chemistry. Efficient catalysis of these reactions classically recourses to heterogeneous or homogeneous transition-metal species. Whether thermal or electrochemical, C-C multiple bond catalytic hydrogenations commonly involve metal hydrides as key intermediates. Here, we report that the electrocatalytic alkyne semihydrogenation by molecular Ni bipyridine complexes proceeds without the mediation of a hydride intermediate. Through a combined experimental and theoretical investigation, we disclose a mechanism that primarily involves a nickelacyclopropene resting state upon alkyne binding to a low-valent Ni(0) species. A following sequence of protonation and electron transfer steps via Ni(II) and Ni(I) vinyl intermediates then leads to olefin release in an overall ECEC-type pattern as the most favored pathway. Our results also evidence that pathways involving hydride intermediates are strongly disfavored, which in turn promotes high semihydrogenation selectivity by avoiding competing hydrogen evolution. While bypassing catalytically competent hydrides, this type of mechanism still retains inner-metal-sphere characteristics with the formation of organometallic intermediates, often essential to control regio- or stereoselectivity. We think that this approach to electrocatalytic reductions of unsaturated organic groups can open new paradigms for hydrogenation or hydroelementation reactions.

Hydrogen addition reactions of a three-membered ring in the solid state: c-C3H2O

Abstract Due to the relatively high abundance of hydrogen radicals in the interstellar medium, the H-addition reaction of unsaturated organic molecules in the solid phase and at very low temperatures is considered to play an important role in the chemical complexity of organic substances in the Universe. However, when interacting with hydrogen atoms, all unsaturated functional groups that may be present in several organic species exhibit different behaviours that can significantly alter the reaction pathways from one species to another. By coupling FTIR spectroscopy and temperature programmed desorption mass spectrometry, we have investigated the H + c-C3H2O (cyclopropenone) solid-state reaction using two different experimental methods. We show that cyclopropenone reacts with hydrogen atoms under interstellar medium conditions, leading to propynal (HCCCHO), propadienone (CH2CCO), and two thermodynamically most stable isomers of c-C3H2O. In excess of H atoms, the hydrogenation of cyclopropenone also leads to propenal (CH2CHCHO), propanal (CH3CH2CHO), c-C3H4O (cyclopropanone), in addition to two alcohols, namely cyclopropanol (c-C3H6O) and propanol (CH3CH2CH2OH).

Preparation and Characterization of a Photo-Crosslinked Methacryloyl-Collagen Composite Film to Promote Corneal Nerve Regeneration via Surface Grafting of Taurine Molecules.

Blindness is frequently caused by corneal abnormalities, and corneal transplantation is the most effective treatment method. It is extremely important to develop high-quality artificial corneas because there are not enough donor corneas accessible for cornea transplantation. One of the most-often utilized materials is collagen, which is the primary component of natural cornea. Collagen-based corneal repair materials have good physicochemical properties and excellent biocompatibility, but how to promote the regeneration of the corneal nerve after keratoplasty is still a big challenge. In this research, in order to promote the growth of nerve cells on a collagen (Col) substrate, a novel collagen-based material was synthesized starting from the functionalization of collagen with unsaturated methacryloyl groups that three-dimensionally photopolymerize to a 3D network of chemically crosslinked collagen (ColMA), onto which taurine molecules were eventually grafted (ColMA-Tr). The physicochemical properties and biocompatibility of the Col, ColMA and ColMA-Tr films were evaluated. By analyzing the results, we found that all the three samples had good moisture retention and aq high covalent attachment of methacryloyl groups followed by their photopolymerization improved the mechanical properties of the ColMA and ColMA-Tr. Most importantly, compared with ColMA, the taurine-modified collagen-MA film significantly promoted the growth of nerve cells and corneal epithelial cells on its surface. Our preliminary results suggest that this novel ColMA-Tr film may have potential use in cornea tissue engineering in the future.

Recent Advances on Heterogeneous Non-noble Metal Catalysts toward Selective Hydrogenation Reactions

Selective hydrogenation reactions provide a pivotal and promising strategy for upgrading substances with unsaturated functional groups, in which supported non-noble metal catalysts play a crucial role in determining catalytic performance toward desirable products. By means of a precipitation method, hydrothermal and solvothermal methods, sol–gel synthesis as well as ion exchange method, various kinds of supported catalysts with high efficiency have been reasonably designed and developed. The detailed investigations by virtue of comprehensive studies demonstrated that in addition to the inherent properties of metal elements, the nanosized effect, the metal-alloy effect, and the metal–support interaction impose significant influences on the resulting catalytic behavior. Moreover, we discuss the catalytic applications of heterogeneous non-noble metal catalysts with focus on the catalytic hydrogenation of unsaturated aldehydes/ketones, alkynes and alkadienes, and functionalized nitroaromatic hydrocarbons. In this review, on the basis of achievements in the representative investigations, suggestions and prospects for the further progresses in the development of heterogeneous non-noble metal catalysts toward selective hydrogenation reactions have been put forward.

Photo-manipulated polyunsaturated fatty acid-doped liposomal hydrogel for flexible photoimmunotherapy

Despite the synergy of immune checkpoint blockade (ICB) therapy and photodynamic therapy (PDT) holds great promise as countermeasures against breast cancer, exploring long-term or flexible short-time therapeutic strategies in “cold” tumors remains a great challenge. Here, we present a polyunsaturated fatty acid-doped liposomal hydrogel Lp(DHA)@CP Gel loaded with photosensitizer chlorin e6 (Ce6) and programmed death-ligand 1 antibody (αPD-L1) for flexible local photoimmunotherapy with merely single-dosed administration. The presence of polyunsaturated fatty acid (docosahexaenoic acid, DHA) doped in particle membrane endows liposomes with flexibly reactive oxygen species (ROS)-responsive release capability, which was attributed to the presence of abundant unsaturated groups. The αPD-L1 was repeatedly induced to in situ release in response to the PDT under photo-exposure. The immunogenic cell death (ICD) effect of PDT evoked “cold” breast tumor to “hot” one, and then assisted the cascade released αPD-L1 to synergistically boost the immunotherapy. After a single dose of peritumoral administration of Lp(DHA)@CP Gel, the on-demand treatment can maximize patient compliance and safety by adjusting therapeutic behaviors via a photo on-off switch. This work presents a flexible medication platform, showing promise in improving the objective response rate of ICB therapy and minimizing its systemic toxicity.

The crosslink between the hyaluronic acid and drugs treated by reactive oxygen species produced in plasma based on the molecular dynamics simulation

Hyaluronic Acid (HA)-based pre-drugs can enable targeted drug delivery to cancer cells with CD44-high expressing, thus, it is essential to design an efficient, target specific drug delivery system based on HA. Plasma, as a simple and clean tool, has been widely used in the modification and crosslinking of biological materials in recent years. In this paper, we used the Reactive Molecular Dynamic (RMD) to explore the reaction between reactive oxygen species (ROS) in plasma and HA with drugs (PTX, SN-38, and DOX), in order to examine possible drug-coupled systems. The simulation results indicated the acetylamino groups in HA could be oxidized to unsaturated acyl groups, which offers the possibility of crosslinking. Three drugs also exposed the unsaturated atoms under the impact of ROS, which can cross-link directly to HA through CO and CN bonds, forming a drug coupling system with better release. This study revealed the exposure of active sites on HA and drugs by ROS impact in plasma, allowing us to study the crosslinking mechanism between HA and drugs at molecular level deeply, and also provided a new light for establishment of HA-based targeted drug delivery system.

Construction of N-Doped Carbon-Modified Ni/SiO2 Catalyst Promoting Cinnamaldehyde Selective Hydrogenation.

At present, the selective hydrogenation of α, β-unsaturated aldehydes remains a challenge due to competition between unsaturated functional groups (C=C and C=O). In this study, N-doped carbon deposited on silica-supported nickel Mott-Schottky type catalysts (Ni/SiO2@NxC) was prepared for the selective hydrogenation of cinnamaldehyde (CAL) by using the respective hydrothermal method and high-temperature carbonization method. The prepared optimal Ni/SiO2@N7C catalyst achieved 98.9% conversion and 83.1% selectivity for 3-phenylpropionaldehyde (HCAL) in the selective hydrogenation reaction of CAL. By constructing the Mott-Schottky effect, the electron transfer from metallic Ni to N-doped carbon at their contact interface was promoted, and the electron transfer was demonstrated by XPS and UPS. Experimental results indicated that by modulating the electron density of metallic Ni, the catalytic hydrogenation of C=C bonds was preferentially performed to obtain higher HCAL selectivity. Meanwhile, this work also provides an effective way to design electronically adjustable type catalysts for more selective hydrogenation reactions.

Experimental and molecular simulation studies of N, S-doped Carbon dots as an eco-friendly corrosion inhibitor for protecting Cu in HCl environment

A serious of N, S-doped carbon dots (N, S-CDs) as an eco-friendly corrosion inhibitor with different S/N ratios were synthesized by finely tuning the ratio of L-cysteine and ammonium citrate through a hydrothermal method. The chemical composition and morphology of these N, S-CDs were characterized by FTIR, UV-Vis, TEM and XPS techniques. The N, S-CDs showed good dispersion in aqueous solution with average particle size of about 3–6 nm. An abundant of unsaturated bonds and polar groups were found on the surface of the N, S-CDs. The inhibition performance of the N, S-CDs for copper metal in 1.0 M HCl environment was studied by electrochemical, combining FTIR, XPS and Raman to investigate the corrosion products. The inhibition efficiency of N, S-CDs displayed a first increased and then decreased trend with the increasing of S/N ratio. When the mass ratio of L-cysteine and ammonium citrate was 1:2 (L1 sample), the icorr value exhibited a minimum of 11 μA/cm2 at 160 mg/L after immersing for 24 h and the inhibition efficiency reached up to 94 %. N-Cu and S-Cu bond from XPS implied anchoring interactions between copper and N, S-CDs with multiple heteroatoms as active sites. From DFT calculation, the obtained low energy gap (ΔE) represented a strong physicochemical of N, S-CDs on Cu substrate. With its merits of high corrosion inhibition efficiency and low cost, N, S-CDs inhibitor is a very promising alternative to traditional inhibitors and could significantly extend the service life of copper in corrosive environments.

Improving the Treatment Effect of Carotenoids on Alzheimer's Disease through Various Nano-Delivery Systems.

Natural bioactive compounds have recently emerged as a current strategy for Alzheimer's disease treatment. Carotenoids, including astaxanthin, lycopene, lutein, fucoxanthin, crocin and others are natural pigments and antioxidants, and can be used to treat a variety of diseases, including Alzheimer's disease. However, carotenoids, as oil-soluble substances with additional unsaturated groups, suffer from low solubility, poor stability and poor bioavailability. Therefore, the preparation of various nano-drug delivery systems from carotenoids is a current measure to achieve efficient application of carotenoids. Different carotenoid delivery systems can improve the solubility, stability, permeability and bioavailability of carotenoids to a certain extent to achieve Alzheimer's disease efficacy. This review summarizes recent data on different carotenoid nano-drug delivery systems for the treatment of Alzheimer's disease, including polymer, lipid, inorganic and hybrid nano-drug delivery systems. These drug delivery systems have been shown to have a beneficial therapeutic effect on Alzheimer's disease to a certain extent.

Synthesis and identification of aromatic poly (Ester-Amide) containing chalcone groups in backbone chain

The purpose of this research is to synthesize a new monomer (E)-5-(3-(4-aminophenyl)-3-oxoprop-1-en-1-yl)-2-hydroxybenzoic acid and poly (ester-amide) polymer. Chalcone compound, α, β- unsaturated ketone is a new monomer that includes both the functional group (-CO-CH=CH-) and α, β - unsaturated carbonyl group of the present system. It is prepared via the condensation of aryl ketone with an aromatic aldehyde in the presence of suitable condensation agents which is known as condensation of aldol. The monomer was reacted with (phthalic anhydride and maleic anhydride) by solution polycondensation reactions to yield polymer. The synthesized monomer and polymer were characterized via FT.IR-spectra, Nuclear magnetic resonance13 C.NMR-spectra, 1H.NMR-spectra] and DSC (Differential scanning calorimetry)]. The polymer demonstrated excellent thermal stability. The findings revealed that poly (ester-amide) was successfully synthesized by providing a good spectrum that improved the existing amide functional group (-CONH-) and ester functional group (-COO-) in the spectrum of prepared polymer, as well as the presence of chalcone functional groups(CO-CH=CH-) improved in the spectrum of monomer.