Macromol最新文献_第7页

Cross-Linked Polymeric Gels and Nanocomposites: New Materials and Phenomena Enabling Technological Applications 交联聚合物凝胶和纳米复合材料:新材料和现象使技术应用

Macromol Pub Date : 2022-09-02 DOI: 10.3390/macromol2030028

C. Barbero, M. V. Martínez, D. Acevedo, M. Molina, C. Rivarola

{"title":"Cross-Linked Polymeric Gels and Nanocomposites: New Materials and Phenomena Enabling Technological Applications","authors":"C. Barbero, M. V. Martínez, D. Acevedo, M. Molina, C. Rivarola","doi":"10.3390/macromol2030028","DOIUrl":"https://doi.org/10.3390/macromol2030028","url":null,"abstract":"Cross-linked gels are synthesized by homo- and copolymerization of functionalized acrylamides. The gels swell in aqueous solution, and some of them (e.g., poly(N-isopropylacrylamide (PNIPAM)) also in organic solvents of low polarity (e.g., dichloromethane), making the gels amphiphilic materials. Nanocomposites can be made by dispersing nanoparticles (metallic, graphene, nanotubes, and conducting polymers) inside the gels. Additionally, true semi-interpenetrated networks of polyaniline (PANI) inside PNIPAM gels can be prepared by swelling the gel in true solutions of PANI in NMP. PNIPAM-based nanocomposites show a lower critical solution temperature (LCST) transition of the gel matrix, which can be reached by thermal heating or absorption of electromagnetic radiation (light, microwaves, radiofrequency) in the conductive nanomaterials. The characteristic properties (swelling degree and rate, LCST, solute partition, mass transport, hydrophilicity, biocompatibility) can be tuned by changing the functional groups in the copolymers and/or the other components in the nanocomposite. Mass transport and mechanical properties can be adjusted by forming materials with macro- (nanoporous and macroporous), micro- (microgels, thin films, Pickering emulsions), or nano- (nanogels, stabilized nanoparticles) sized features. The material properties are used to produce technological applications: sensors, actuators, controlled release, biological cell scaffolds and surfaces, antimicrobial, carriers of bioactive substances, and matrixes to immobilize enzymes and yeast cells.","PeriodicalId":18139,"journal":{"name":"Macromol","volume":"183 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74651438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Soft Elastomers Based on the Epoxy–Amine Chemistry and Their Use for the Design of Adsorbent Amphiphilic Magnetic Nanocomposites 基于环氧胺化学的软弹性体及其在吸附性两亲磁性纳米复合材料设计中的应用

Macromol Pub Date : 2022-09-02 DOI: 10.3390/macromol2030027

Magda Lorena Arciniegas Vaca, Jimena S. González, C. Hoppe

引用次数: 2

Removal of Heavy Metal Ions from Wastewaters by Using Chitosan/Poly(Vinyl Alcohol) Adsorbents: A Review 壳聚糖/聚乙烯醇吸附剂去除废水中重金属离子的研究进展

Macromol Pub Date : 2022-08-06 DOI: 10.3390/macromol2030026

Dimitrios G. Trikkaliotis, N. Ainali, A. Tolkou, A. Mitropoulos, D. Lambropoulou, D. Bikiaris, G. Kyzas

引用次数: 9

The Stability Consequences Promoted by Doping Metallic Atoms on the Degradation of Poly (ε-Caprolactone) 掺杂金属原子对聚ε-己内酯降解的稳定性影响

Macromol Pub Date : 2022-08-05 DOI: 10.3390/macromol2030025

T. Zaharescu, T. Borbath, M. Mariș, I. Borbath, M. Mariș

{"title":"The Stability Consequences Promoted by Doping Metallic Atoms on the Degradation of Poly (ε-Caprolactone)","authors":"T. Zaharescu, T. Borbath, M. Mariș, I. Borbath, M. Mariș","doi":"10.3390/macromol2030025","DOIUrl":"https://doi.org/10.3390/macromol2030025","url":null,"abstract":"The stability of polymer materials is essentially determined by the molecular structure and the presence of additives and impurities. When a polymer substrate is subjected to vigorous damage by an energetic treatment, the molecular scission generates fragments, which may be oxidized by the diffused oxygen. The traces of oxide catalysts that may be accidentally incorporated into the polymer materials initiate a faster oxidation that influences the material durability. This study presents the behavior of poly (ε-caprolactone) (PCL) loaded with 2 wt% PbZrO3 previously doped with foreign atoms (Cr, Nd, Mg, Mn, Ti) at the concentration of 0.1 mol%. The investigation procedure, chemiluminescence, reveals the acceleration of the degradation of PCL. The contribution of the metallic traces existing in the structure of PbTiO3 powder is characterized by the activation energies (Ea) involved in the propagation of oxidation. The free radicals are involved in a faster oxidation, when the polymer substrate is heated at superior rates. The comparison of the oxidation levels at the extended period of heating and irradiation indicates the sustained activities of metallic traces acting in oxide powder fillers, especially at temperatures exceeding 150 °C. The essential considerations on material strength against oxidation are presented.","PeriodicalId":18139,"journal":{"name":"Macromol","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90790745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetic Nanoparticles for Medical Applications: Updated Review 磁性纳米颗粒在医学上的应用:最新综述

Macromol Pub Date : 2022-08-02 DOI: 10.3390/macromol2030024

G. G. Flores-Rojas, F. López-Saucedo, R. Vera-Graziano, E. Mendizábal, E. Bucio

引用次数: 26

Rheological and Stability Evaluation of Emulsions Containing Fenugreek Galactomannan—Xanthan Gum Mixtures: Effect of Microwave and Ultrasound Treatments 含胡芦巴半乳甘露-黄原胶混合物乳剂的流变性和稳定性评价:微波和超声处理的影响

Macromol Pub Date : 2022-08-01 DOI: 10.3390/macromol2030023

Rasoul Niknam, M. Soudi, M. Mousavi

{"title":"Rheological and Stability Evaluation of Emulsions Containing Fenugreek Galactomannan—Xanthan Gum Mixtures: Effect of Microwave and Ultrasound Treatments","authors":"Rasoul Niknam, M. Soudi, M. Mousavi","doi":"10.3390/macromol2030023","DOIUrl":"https://doi.org/10.3390/macromol2030023","url":null,"abstract":"The effects of treating two biopolymers (Trigonella foenum—graceum galactomannan and xanthan gum mixtures) with microwaves and ultrasound on the rheological aspects of O/W emulsions were investigated. The data obtained from steady shear flow were fitted with various models and the best were chosen due to the values of R2 and RMSE. The oscillatory shear rheology data demonstrated that the emulsions not treated with microwaves or ultrasound had viscous-like behavior and treated samples demonstrated weak gel behavior. The values obtained for various rheological parameters (especially apparent viscosity, storage modulus and loss modulus) indicated that fenugreek galactomannan had more impact on the rheological aspects of emulsions in comparison with xanthan gum. In addition, the synergistic interaction between two biopolymers, particularly in samples treated with ultrasound, resulted in better rheological aspects which could be affiliated with the strong bonds between the hydrocolloids. By treating the samples with microwaves and ultrasound, the emulsion stability values of the samples (especially those with a high ratio of galactomannan) significantly increased, which might be connected with various parameters, especially viscosity.","PeriodicalId":18139,"journal":{"name":"Macromol","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73566769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Advances in Alkylated Chitosan and Its Applications for Hemostasis 烷基化壳聚糖及其止血应用研究进展

Macromol Pub Date : 2022-07-27 DOI: 10.3390/macromol2030022

Huiyang Jin, Zhengke Wang

引用次数: 9

Biodegradable Films from Kefiran-Based Cryogel Systems 基于kefiran的低温凝胶系统的可生物降解膜

Macromol Pub Date : 2022-07-13 DOI: 10.3390/macromol2030021

S. Exarhopoulos, A. Goulas, G. Dimitreli

{"title":"Biodegradable Films from Kefiran-Based Cryogel Systems","authors":"S. Exarhopoulos, A. Goulas, G. Dimitreli","doi":"10.3390/macromol2030021","DOIUrl":"https://doi.org/10.3390/macromol2030021","url":null,"abstract":"Kefiran, which was isolated from kefir grains, was used for the fabrication of cryogel-films in the presence of plasticizers, such as glycerol and sorbitol. Varying concentration ratios of the exopolysaccharide/plasticizer system were employed in the process of the cryogel-film formulation and their effect on the physical (film thickness, moisture content, and solubility) and the mechanical (tensile strength and elongation at break) properties of the films was monitored. Kefiran-film vapor adsorption isotherms were calculated, and a thermal analysis of the samples was also performed. The structural characteristics of the cryogel-films were observed using confocal laser scanning microscopy. The cryo-treatment, alongside the plasticizer addition, affected the physical and mechanical properties of the kefiran films, as well as their morphology. Increasing kefiran concentration resulted in increasing the film thickness, the moisture content, and the tensile strength, while decreased their solubility and their elongation at break. Kefiran-film adsorption isotherms were affected by the cryo-treatment, the kefiran concentration, and the plasticizer use and concentration. The thermal analysis of the kefiran films showed thermal stability. The presence of the plasticizers and their increment concentration resulted in decreasing the glass transition and the melting temperatures. The cryo-treatment and the presence of plasticizers resulted in the films appearing smoother. Glycerol proved to affect more than the sorbitol–water vapor adsorption and the morphology of kefiran films.","PeriodicalId":18139,"journal":{"name":"Macromol","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80134145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Morphological and Viscoelastic Properties of the Cicada Tymbal 蝉鼓室的形态和粘弹性

Macromol Pub Date : 2022-07-07 DOI: 10.3390/macromol2030020

Fahrunnida, P. R. Sayekti, C. Robert, B. Retnoaji, Parvez Alam

{"title":"Morphological and Viscoelastic Properties of the Cicada Tymbal","authors":"Fahrunnida, P. R. Sayekti, C. Robert, B. Retnoaji, Parvez Alam","doi":"10.3390/macromol2030020","DOIUrl":"https://doi.org/10.3390/macromol2030020","url":null,"abstract":"This paper focusses on the morphological and viscoelastic properties of the cicada tymbal from the species Dundubia rufivena. Morphological details were determined by scanning electron and fluorescence microscopy, while the viscoelastic properties were determined by dynamic mechanical thermal analysis, and further supported by differential scanning calorimetry. We find that water evaporation from the tymbal begins at 71.1 °C and the glass transition for the tymbal, which is a chitin–resilin composite, is on average 150 °C, though there is considerable heterogeneity in the material of the tymbal, as indicated by the half height peak width of the tymbal (35.3 °C) and the shoulder peak indicative of a second phase and hence glass transition at on average, 168 °C. This second phase is assumed to reflect the effects of large-scale molecular pinning and restructuring at resilin–chitin interfaces (possibly via specific binding domains). In addition, we elucidate that the predominantly resilin regions of the tymbal of Dundubia rufivena is reinforced by a polygonal mesh of chitin, a morphological feature that has not been described in any previous research on the cicada tymbal. We provide evidence for nonlinear elasticity in the tymbal by comparing the storage modulus of the tymbal at different frequencies and loading amplitudes.","PeriodicalId":18139,"journal":{"name":"Macromol","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82765546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessment of Bio-Based Polyurethanes: Perspective on Applications and Bio-Degradation 生物基聚氨酯的评价:应用前景和生物降解

Macromol Pub Date : 2022-07-04 DOI: 10.3390/macromol2030019

R. Kaur, Pooja Singh, Surya Tanwar, Gunjan Varshney, S. Yadav

{"title":"Assessment of Bio-Based Polyurethanes: Perspective on Applications and Bio-Degradation","authors":"R. Kaur, Pooja Singh, Surya Tanwar, Gunjan Varshney, S. Yadav","doi":"10.3390/macromol2030019","DOIUrl":"https://doi.org/10.3390/macromol2030019","url":null,"abstract":"Among numerous synthetic macromolecules, polyurethane in its different forms has proven its sheer dominance and established a reputation as a reliable and trusted material due to its proficiency in terms of superior properties, which include: high mechanical strength and abrasion resistance, good durability, good adhesion, good thermal stability, excellent chemical and weathering resistance. Synthetic polyurethane materials are non-biodegradable, poisonous, and use petrochemical-based raw materials, which are now depleting, leading to a surge in polyurethane production costs. Bio-based polyurethanes (PU) have been synthesized by researchers in recent decades and have mostly overtaken petrochemical-based PU in terms of challenges such as solid pollution, economic effectiveness, and availability of raw materials. Enormous kinds of available bio-renewable sources as predecessors for the production of polyols and isocyanates have been explored for the development of “greener” PU materials; these bio-based polyurethanes have significant potential to be used as future PU products, with a partial or total replacement of petroleum-based polyurethanes, due to increasing concern about the environment, their relatively low cost and biodegradability. This critical review concentrates on the possibilities of renewable sources to be used for polyurethane production and gives a clear perspective on the journey, utilization, and recent advancements in the field of different bio-based polyurethane polymers that have arisen over the last decade.","PeriodicalId":18139,"journal":{"name":"Macromol","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82353424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 31