The work aimed to assess the restoration of metal-contaminated soil pH and EC and impacts on Cd accumulation in plants Helianthus annuus (Sunflower) through tea waste in a natural environment. Various doses of Cd metal treatment (1–5 ppm) were provided to the soil with two sets of organic matter (tea waste) in a dry and wet state. The soil and plants were analyzed using analytical procedures like AAS, SEM and EDS, while pH and EC were measured through pH and conductivity meter. The mitigating effect of tea waste was observed on the pH (6.2–6.9) and EC of the soil, which was reflected by the healthy growth of the plants. It was established that the movement of the Cd was successfully controlled with the restoration of essential nutrient elements in different parts of plants. It was strongly related to recovered soil pH and EC in two sets of tested H. annuus plant species. The healthy growth of the plants showed that tea waste acts as a safe, harmless and sound remediator of soil, which enhances the soil nutrient ionic activity from soil to roots of the plants in the presence of the Cd metal, effective for the use of agriculture purposes.
{"title":"Bioremediation of cadmium contaminated soil by tea waste and impact on the accumulation of Cd in Helianthus annuus","authors":"Sumeira Moin, Rafia Azmat, Ailyan Saleem, Tehseen Ahmed, Waseem Ahmed, Khalid Ahmed, Neelofer Hamid, Sajid Ali, Abdulwahed Fahad Alrefaei, Imran Malik","doi":"10.1515/pac-2023-1018","DOIUrl":"https://doi.org/10.1515/pac-2023-1018","url":null,"abstract":"The work aimed to assess the restoration of metal-contaminated soil pH and EC and impacts on Cd accumulation in plants <jats:italic>Helianthus annuus</jats:italic> (Sunflower) through tea waste in a natural environment. Various doses of Cd metal treatment (1–5 ppm) were provided to the soil with two sets of organic matter (tea waste) in a dry and wet state. The soil and plants were analyzed using analytical procedures like AAS, SEM and EDS, while pH and EC were measured through pH and conductivity meter. The mitigating effect of tea waste was observed on the pH (6.2–6.9) and EC of the soil, which was reflected by the healthy growth of the plants. It was established that the movement of the Cd was successfully controlled with the restoration of essential nutrient elements in different parts of plants. It was strongly related to recovered soil pH and EC in two sets of tested <jats:italic>H. annuus</jats:italic> plant species. The healthy growth of the plants showed that tea waste acts as a safe, harmless and sound remediator of soil, which enhances the soil nutrient ionic activity from soil to roots of the plants in the presence of the Cd metal, effective for the use of agriculture purposes.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"67 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139645082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biopolymer-based materials for the adsorption of toxic dyes represent an interesting class of materials for environmental applications. Here we report on chitosan as the starting material for synthesizing dye adsorbents. In particular, the synthesis, characterization, and cationic dye adsorption properties of chitosan hydrogel adsorbents are reported. Polyanionic itaconated chitosan derivatives were synthesized in solvent-less conditions for the first time. Itaconated chitosan was cross-linked using thiol-ene chemistry to obtain hydrogels. The influence of the incorporated carboxylate groups and the cross-linker fraction on the adsorption of Methylene Blue (MB) was investigated. In addition, the impact of pH, adsorbent dose, initial concentration, and ionic strength were investigated to determine the optimum conditions for MB uptake, and the dye uptake kinetics, adsorption isotherms, selectivity, and reusability of the adsorbents were unveiled. A maximum adsorption capacity of 556 mg/g could be achieved, outperforming commercial activated charcoal and ion exchange resins. Furthermore the chitosan hydrogel adsorbents were shown to capture >90 % of cationic MB from a binary equimolar mixture with the anionic dye Methyl Orange. Since the adsorbents can be regenerated and re-used afterwards at least 20 times, retaining a high dye adsorption fraction of >95 %, these materials are promising candidates for environmental applications.
{"title":"Green chemistry route to chitosan hydrogels and investigation of the materials as efficient dye adsorbents","authors":"Dennis Gitau Njuguna, Holger Schönherr","doi":"10.1515/pac-2023-1005","DOIUrl":"https://doi.org/10.1515/pac-2023-1005","url":null,"abstract":"Biopolymer-based materials for the adsorption of toxic dyes represent an interesting class of materials for environmental applications. Here we report on chitosan as the starting material for synthesizing dye adsorbents. In particular, the synthesis, characterization, and cationic dye adsorption properties of chitosan hydrogel adsorbents are reported. Polyanionic itaconated chitosan derivatives were synthesized in solvent-less conditions for the first time. Itaconated chitosan was cross-linked using thiol-ene chemistry to obtain hydrogels. The influence of the incorporated carboxylate groups and the cross-linker fraction on the adsorption of Methylene Blue (MB) was investigated. In addition, the impact of pH, adsorbent dose, initial concentration, and ionic strength were investigated to determine the optimum conditions for MB uptake, and the dye uptake kinetics, adsorption isotherms, selectivity, and reusability of the adsorbents were unveiled. A maximum adsorption capacity of 556 mg/g could be achieved, outperforming commercial activated charcoal and ion exchange resins. Furthermore the chitosan hydrogel adsorbents were shown to capture >90 % of cationic MB from a binary equimolar mixture with the anionic dye Methyl Orange. Since the adsorbents can be regenerated and re-used afterwards at least 20 times, retaining a high dye adsorption fraction of >95 %, these materials are promising candidates for environmental applications.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"33 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139644976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Immense research efforts on graphene or graphene oxide have led to the formation of unique nanocarbon derived nanomaterials. Graphene and graphene oxide have been reinforced in polymeric matrices to form high performance nanocomposites. Significant applications of polymer nanocomposites with graphene or graphene oxide were experiential for nanofiber formation and ensuing membranes. This overview highlights design, essential features, and potential of graphene or graphene oxide derived nanocomposite nanofibrous membranes for water remediation permeation towards contaminates, salts, toxins, microbials, and other separation purposes. Here, polymer filled graphene or graphene oxide nanocomposites have been processed into nanofibers using appropriate techniques such as electrospinning, wet spinning, template method, etc. Afterwards, polymer/graphene and polymer/graphene oxide nanofiber nanocomposites were applied to form the nanocomposite membranes using appropriate techniques like solution processing, casting methods, infiltration, etc. Consequently, high performance membranes have been researched for technological purposes, especially water management competence. Future research on polymer/graphene nanofibrous membranes may lead to highly efficient systems for commercial and industrial level uses.
{"title":"Nanocomposite nanofibrous membranes of graphene and graphene oxide: water remediation potential","authors":"Ayesha Kausar, Ishaq Ahmad, Tran Dai Lam","doi":"10.1515/pac-2023-0803","DOIUrl":"https://doi.org/10.1515/pac-2023-0803","url":null,"abstract":"Immense research efforts on graphene or graphene oxide have led to the formation of unique nanocarbon derived nanomaterials. Graphene and graphene oxide have been reinforced in polymeric matrices to form high performance nanocomposites. Significant applications of polymer nanocomposites with graphene or graphene oxide were experiential for nanofiber formation and ensuing membranes. This overview highlights design, essential features, and potential of graphene or graphene oxide derived nanocomposite nanofibrous membranes for water remediation permeation towards contaminates, salts, toxins, microbials, and other separation purposes. Here, polymer filled graphene or graphene oxide nanocomposites have been processed into nanofibers using appropriate techniques such as electrospinning, wet spinning, template method, etc. Afterwards, polymer/graphene and polymer/graphene oxide nanofiber nanocomposites were applied to form the nanocomposite membranes using appropriate techniques like solution processing, casting methods, infiltration, etc. Consequently, high performance membranes have been researched for technological purposes, especially water management competence. Future research on polymer/graphene nanofibrous membranes may lead to highly efficient systems for commercial and industrial level uses.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"291 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139581465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Limya Yagoup Osman, Talal Ahmed Awad, Sahar Abdalla, Mohamed Osman El-Faki, Amna Ali, Eltayeb Fadul Fadul Alla
In this study, we examined the potential anti-Alzheimer’s and antioxidant activities of 12 analogs of coumarin and flavone compounds. Notably, nitro coumarins 6 and 7 demonstrated noteworthy activity against acetylcholinesterase, although they did not exhibit antioxidant properties. Among the tested compounds, four flavones and one coumarin displayed dual activity as both inhibitors of acetylcholinesterase and antioxidants. Particularly, flavone 9 exhibited exceptional antioxidant activity as well as substantial anti-cholinesterase activity. Molecular docking techniques were employed to investigate the relationship between the anti-Alzheimer’s and antioxidant potential of the compounds. Intriguingly, compound 9 displayed the strongest binding energy values with both monoamine oxidase-B (MAO-B) enzyme (−15.70 kcal/mol) and acetylcholinesterase enzyme (−21.70 kcal/mol), indicating that its antioxidant activity may be attributed to MAO-B inhibition. The pharmacokinetic and safety profiles of five compounds (5, 6, 7, 8, and 9) were examined using pkCSM server, revealing varying characteristics in absorption, CYP enzyme interactions, and toxicity. Compound 8 displays high absorption and lower toxicity, while Compound 6 emerges as a promising candidate due to favorable overall attributes. Nonetheless, comprehensive evaluation, including clinical studies, is crucial for determining their suitability for human use.
{"title":"In silico and in vitro profiling of coumarins and flavonoids for anti-Alzheimer and antioxidant activity","authors":"Limya Yagoup Osman, Talal Ahmed Awad, Sahar Abdalla, Mohamed Osman El-Faki, Amna Ali, Eltayeb Fadul Fadul Alla","doi":"10.1515/pac-2023-1110","DOIUrl":"https://doi.org/10.1515/pac-2023-1110","url":null,"abstract":"In this study, we examined the potential anti-Alzheimer’s and antioxidant activities of 12 analogs of coumarin and flavone compounds. Notably, nitro coumarins 6 and 7 demonstrated noteworthy activity against acetylcholinesterase, although they did not exhibit antioxidant properties. Among the tested compounds, four flavones and one coumarin displayed dual activity as both inhibitors of acetylcholinesterase and antioxidants. Particularly, flavone 9 exhibited exceptional antioxidant activity as well as substantial anti-cholinesterase activity. Molecular docking techniques were employed to investigate the relationship between the anti-Alzheimer’s and antioxidant potential of the compounds. Intriguingly, compound 9 displayed the strongest binding energy values with both monoamine oxidase-B (MAO-B) enzyme (−15.70 kcal/mol) and acetylcholinesterase enzyme (−21.70 kcal/mol), indicating that its antioxidant activity may be attributed to MAO-B inhibition. The pharmacokinetic and safety profiles of five compounds (5, 6, 7, 8, and 9) were examined using pkCSM server, revealing varying characteristics in absorption, CYP enzyme interactions, and toxicity. Compound 8 displays high absorption and lower toxicity, while Compound 6 emerges as a promising candidate due to favorable overall attributes. Nonetheless, comprehensive evaluation, including clinical studies, is crucial for determining their suitability for human use.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"214 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chalcone is an important biosynthetic precursor, due to the diverse pharmacological activities. The aim of this current study was to synthesize 14 new chalcone derivatives compounds by incorporating p-alkoxyacetophenones with substituted benzaldehydes. Two new series of chalcone derivatives have been synthesized using the alkylation and the base catalysed Claisen-Schmidt condensation. All the synthesized compounds were fully characterized by IR, 1D NMR (1H and 13C NMR) and 2D NMR (COSY, HMQC, HMBC) as well as mass spectrometry analysis. All the synthesized compounds were assayed in vitro for their antituberculosis activities against Mycobacterium tuberculosis strain. Among them, compounds (E)-1-[4-(heptoxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5a), (E)-1-[4-(octyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5b) and (E)-1-[4-(decyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5d) showed good activities with the lowest MIC value of 12.5 μg/mL.
{"title":"Synthesis of some chalcones derivatives series and their antituberculosis activity","authors":"Noviany Noviany, Hasnah Osman, Suriyati Mohamad, Sutopo Hadi, Heri Satria, Buhani Buhani","doi":"10.1515/pac-2023-1127","DOIUrl":"https://doi.org/10.1515/pac-2023-1127","url":null,"abstract":"Chalcone is an important biosynthetic precursor, due to the diverse pharmacological activities. The aim of this current study was to synthesize 14 new chalcone derivatives compounds by incorporating <jats:italic>p</jats:italic>-alkoxyacetophenones with substituted benzaldehydes. Two new series of chalcone derivatives have been synthesized using the alkylation and the base catalysed Claisen-Schmidt condensation. All the synthesized compounds were fully characterized by IR, 1D NMR (<jats:sup>1</jats:sup>H and <jats:sup>13</jats:sup>C NMR) and 2D NMR (COSY, HMQC, HMBC) as well as mass spectrometry analysis. All the synthesized compounds were assayed <jats:italic>in vitro</jats:italic> for their antituberculosis activities against <jats:italic>Mycobacterium tuberculosis</jats:italic> strain. Among them, compounds (<jats:italic>E</jats:italic>)-1-[4-(heptoxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5a), (<jats:italic>E</jats:italic>)-1-[4-(octyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5b) and (<jats:italic>E</jats:italic>)-1-[4-(decyloxy)phenyl]-3-(2-hydroxy-5-bromophenyl)prop-2-en-1-one (5d) showed good activities with the lowest MIC value of 12.5 μg/mL.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"171 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Silver and lanthanide (Tm3+, Yb3+) doped oxyfluoride glasses have been prepared by melt-quenching method. The absorption of the glasses was measured in the range from 350 to 550 nm revealing the absorption edges of Ag nanoclusters and Tm3+ transition. The photoluminescence spectra of the glasses were detected in the range from 400 to 1100 nm under excitation in the range from 300 to 500 nm. The photoluminescence excitation spectra showed that Ag nanoclusters and Tm3+ ions can effectively harvest energy in UV-range and convert to visible and infrared (through emission by Yb3+ ions) ranges making the glasses perspective as white light emitters and solar spectrum downconverters.
{"title":"Luminescence of silver, thulium and ytterbium doped oxyfluoride glasses","authors":"Mikhail V. Shestakov, Victor V. Moshchalkov","doi":"10.1515/pac-2023-1106","DOIUrl":"https://doi.org/10.1515/pac-2023-1106","url":null,"abstract":"Silver and lanthanide (Tm<jats:sup>3+</jats:sup>, Yb<jats:sup>3+</jats:sup>) doped oxyfluoride glasses have been prepared by melt-quenching method. The absorption of the glasses was measured in the range from 350 to 550 nm revealing the absorption edges of Ag nanoclusters and Tm<jats:sup>3+</jats:sup> transition. The photoluminescence spectra of the glasses were detected in the range from 400 to 1100 nm under excitation in the range from 300 to 500 nm. The photoluminescence excitation spectra showed that Ag nanoclusters and Tm<jats:sup>3+</jats:sup> ions can effectively harvest energy in UV-range and convert to visible and infrared (through emission by Yb<jats:sup>3+</jats:sup> ions) ranges making the glasses perspective as white light emitters and solar spectrum downconverters.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"115 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giuseppe Resnati, David L. Bryce, Gautam R. Desiraju, Antonio Frontera, Ingo Krossing, Anthony C. Legon, Pierangelo Metrangolo, Francesco Nicotra, Kari Rissanen, Steve Scheiner, Giancarlo Terraneo
This recommendation proposes a definition for the term “pnictogen bond”; the term pnictogen bond designates a subset of the attractive interactions between an electrophilic region on a pnictogen atom in a molecular entity and a nucleophilic region in another, or the same, molecular entity.
{"title":"Definition of the pnictogen bond (IUPAC Recommendations 2023)","authors":"Giuseppe Resnati, David L. Bryce, Gautam R. Desiraju, Antonio Frontera, Ingo Krossing, Anthony C. Legon, Pierangelo Metrangolo, Francesco Nicotra, Kari Rissanen, Steve Scheiner, Giancarlo Terraneo","doi":"10.1515/pac-2020-1002","DOIUrl":"https://doi.org/10.1515/pac-2020-1002","url":null,"abstract":"This recommendation proposes a definition for the term “pnictogen bond”; the term pnictogen bond designates a subset of the attractive interactions between an <jats:italic>electrophilic</jats:italic> region on a <jats:italic>pnictogen</jats:italic> atom in a <jats:italic>molecular entity</jats:italic> and a <jats:italic>nucleophilic</jats:italic> region in another, or the same, molecular entity.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"383 2 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
It is widely recognized that electrostatics plays a central role in the intermolecular interactions in condensed phases, as evidenced by the “electrostatics + Lennard-Jones” form of the potential functions that are commonly used in classical molecular dynamics simulations. Then, do we understand all about electrostatics in condensed phases? In this review, recent theoretical advances in relation to this topic will be discussed: (1) vibrational spectroscopic probing of the electrostatics in condensed phases, and (2) some phenomena affected by deviation from the scheme of isotropic fixed atomic partial charges, i.e., anisotropy and intermolecular transfer of electron distributions. A theoretical basis for better understanding on them and some theoretical models for practical calculations will be shown with some typical example cases of hydrogen- and halogen-bonded systems.
{"title":"Roles of electrostatics and intermolecular electronic motions in the structural and spectroscopic features of hydrogen- and halogen-bonded systems","authors":"Hajime Torii","doi":"10.1515/pac-2023-1202","DOIUrl":"https://doi.org/10.1515/pac-2023-1202","url":null,"abstract":"It is widely recognized that electrostatics plays a central role in the intermolecular interactions in condensed phases, as evidenced by the “electrostatics + Lennard-Jones” form of the potential functions that are commonly used in classical molecular dynamics simulations. Then, do we understand all about electrostatics in condensed phases? In this review, recent theoretical advances in relation to this topic will be discussed: (1) vibrational spectroscopic probing of the electrostatics in condensed phases, and (2) some phenomena affected by deviation from the scheme of isotropic fixed atomic partial charges, <jats:italic>i.e.</jats:italic>, anisotropy and intermolecular transfer of electron distributions. A theoretical basis for better understanding on them and some theoretical models for practical calculations will be shown with some typical example cases of hydrogen- and halogen-bonded systems.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"72 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139510064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Poly(ethylene terephthalate) (PET) is a widely used thermoplastic polymer with exceptional properties, making it a cornerstone in various industries. However, the extensive global demand for PET, particularly in the packaging sector, has led to significant ecological concerns due to inadequate recycling rates. This paper explores the potential of Meldrum’s acid-based chain extenders as a solution to enhance PET recycling. Initially, 2,2,5-trimethyl-5-(4-vinylbenzyl)-1,3-dioxane-4,6-dione (St-MA) was synthesized, and its homopolymers were produced through free radical polymerization and characterized through 1H NMR, FTIR and TGA analyses. Dynamic interactions between recycled PET (rPET) and the synthesized chain extender (HP) in an extrusion environment was further explored, resulting in higher Tg and Tc for rPET when 0.5 wt% of HP was added as a reactive chain extender. The chemical tunability of this functional ketene-based chain extender holds promise to enhance PET recycling practices. The continuous evolution of regulatory frameworks and environmental concerns may prompt the exploration of novel approaches, such as tailored Meldrum’s acid-bearing chain extenders, which might have the potential to reduce the ecological consequences associated with post-consumer PET waste.
聚对苯二甲酸乙二醇酯（PET）是一种广泛使用的热塑性聚合物，其优异的性能使其成为各行各业的基石。然而，全球对 PET 的广泛需求，尤其是在包装领域，却因回收率不足而引发了严重的生态问题。本文探讨了美杜伦酸基扩链剂作为提高 PET 回收利用率的解决方案的潜力。首先合成了 2,2,5-三甲基-5-(4-乙烯基苄基)-1,3-二恶烷-4,6-二酮（St-MA），然后通过自由基聚合生产了其均聚物，并通过 1H NMR、FTIR 和 TGA 分析对其进行了表征。进一步探讨了再生 PET（rPET）和合成的扩链剂（HP）在挤出环境中的动态相互作用，结果发现当添加 0.5 wt%的 HP 作为活性扩链剂时，rPET 的 T g 和 T c 都较高。这种功能性酮基扩链剂的化学可调性为改进 PET 回收利用实践带来了希望。监管框架和环境问题的不断演变可能会促使人们探索新的方法，例如量身定制的 Meldrum 含酸扩链剂，这种方法有可能减少与消费后 PET 废弃物相关的生态后果。
{"title":"Exploring the potential of Meldrum’s acid-bearing chain extenders for mechanical recycling of PET","authors":"Yonca Alkan Goksu","doi":"10.1515/pac-2023-1123","DOIUrl":"https://doi.org/10.1515/pac-2023-1123","url":null,"abstract":"Poly(ethylene terephthalate) (PET) is a widely used thermoplastic polymer with exceptional properties, making it a cornerstone in various industries. However, the extensive global demand for PET, particularly in the packaging sector, has led to significant ecological concerns due to inadequate recycling rates. This paper explores the potential of Meldrum’s acid-based chain extenders as a solution to enhance PET recycling. Initially, 2,2,5-trimethyl-5-(4-vinylbenzyl)-1,3-dioxane-4,6-dione (St-MA) was synthesized, and its homopolymers were produced through free radical polymerization and characterized through <jats:sup>1</jats:sup>H NMR, FTIR and TGA analyses. Dynamic interactions between recycled PET (rPET) and the synthesized chain extender (HP) in an extrusion environment was further explored, resulting in higher <jats:italic>T</jats:italic> <jats:sub>g</jats:sub> and <jats:italic>T</jats:italic> <jats:sub>c</jats:sub> for rPET when 0.5 wt% of HP was added as a reactive chain extender. The chemical tunability of this functional ketene-based chain extender holds promise to enhance PET recycling practices. The continuous evolution of regulatory frameworks and environmental concerns may prompt the exploration of novel approaches, such as tailored Meldrum’s acid-bearing chain extenders, which might have the potential to reduce the ecological consequences associated with post-consumer PET waste.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"35 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139496605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antonio Possolo, David Brynn Hibbert, Jürgen Stohner, Olha Bodnar, Juris Meija
This Brief Guide reintroduces readers to the main concepts and technical tools used for the evaluation and expression of measurement uncertainty, including both classical and Bayesian statistical methods. The general approach is the same that was adopted by the Guide to the Expression of Uncertainty in Measurement (GUM): quantities whose values are surrounded by uncertainty are modeled as random variables, which enables the application of a wide range of techniques from probability and statistics to the evaluation of measurement uncertainty. All the methods presented are illustrated with examples involving real measurement results from a wide range of fields of chemistry and related sciences, ranging from classical analytical chemistry as practiced at the beginning to the 20th century, to contemporary studies of isotopic compositions of the elements and clinical trials. The supplementary material offers profusely annotated computer codes that allow the readers to reproduce all the calculations underlying the results presented in the examples.
{"title":"A brief guide to measurement uncertainty (IUPAC Technical Report)","authors":"Antonio Possolo, David Brynn Hibbert, Jürgen Stohner, Olha Bodnar, Juris Meija","doi":"10.1515/pac-2022-1203","DOIUrl":"https://doi.org/10.1515/pac-2022-1203","url":null,"abstract":"This <jats:italic>Brief Guide</jats:italic> reintroduces readers to the main concepts and technical tools used for the evaluation and expression of measurement uncertainty, including both classical and Bayesian statistical methods. The general approach is the same that was adopted by the <jats:italic>Guide to the Expression of Uncertainty in Measurement</jats:italic> (GUM): quantities whose values are surrounded by uncertainty are modeled as random variables, which enables the application of a wide range of techniques from probability and statistics to the evaluation of measurement uncertainty. All the methods presented are illustrated with examples involving real measurement results from a wide range of fields of chemistry and related sciences, ranging from classical analytical chemistry as practiced at the beginning to the 20th century, to contemporary studies of isotopic compositions of the elements and clinical trials. The supplementary material offers profusely annotated computer codes that allow the readers to reproduce all the calculations underlying the results presented in the examples.","PeriodicalId":20911,"journal":{"name":"Pure and Applied Chemistry","volume":"31 1","pages":""},"PeriodicalIF":1.8,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139496636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：