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Abdelsalam S, Hemeda O, Sharshar T, Henaish A, Ali M. Defect probing using positron annihilation and dielectric spectroscopy of PVA/Al thin films. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.132738] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Nabil M, Mahmoud KR, Nomier R, El-Maghraby EM, Motaweh H. Nano-Porous-Silicon Powder as an Environmental Friend. MATERIALS 2021; 14:ma14154252. [PMID: 34361446 PMCID: PMC8347106 DOI: 10.3390/ma14154252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/12/2021] [Accepted: 07/19/2021] [Indexed: 12/01/2022]
Abstract
Nano-porous silicon (NPS) powder synthesis is performed by means of a combination of the ultra-sonication technique and the alkali chemical etching process, starting with a commercial silicon powder. Various characterization techniques {X-ray powder diffraction, transmission electron microscopy, Fourier Transform Infrared spectrum, and positron annihilation lifetime spectroscopy} are used for the description of the product’s properties. The NPS product is a new environmentally friendly material used as an adsorbent agent for the acidic azo-dye, Congo red dye. The structural and free volume changes in NPS powder are probed using positron annihilation lifetime (PALS) and positron annihilation Doppler broadening (PADB) techniques. In addition, the mean free volume (VF), as well as fractional free volume (Fv), are also studied via the PALS results. Additionally, the PADB provides a clear relationship between the core and valence electrons changes, and, in addition, the number of defect types present in the synthesized samples. The most effective parameter that affects the dye removal process is the contact time value; the best time for dye removal is 5 min. Additionally, the best value of the CR adsorption capacity by NPS powder is 2665.3 mg/g at 100 mg/L as the initial CR concentration, with an adsorption time of 30 min, without no impact from temperature and pH. So, 5 min is the enough time for the elimination of 82.12% of the 30 mg/L initial concentration of CR. This study expresses the new discovery of a cheap and safe material, in addition to being environmentally friendly, without resorting to any chemical additives or heat treatments.
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Affiliation(s)
- Marwa Nabil
- Department of Electronic Materials Researches, Advanced Technology and New Materials Research Institute, City for Scientific, Research and Technology Applications, New Borg El-Arab City 21934, Egypt
- Correspondence:
| | - Kamal Reyad Mahmoud
- Department of Physics, Faculty of Science, Kafrelsheikh University, Kafr El Sheikh 33516, Egypt;
| | - Raghda Nomier
- Department of Physics, Faculty of Science, Damanhour University, Damanhur 22511, Egypt; (R.N.); (E.-M.E.-M.); (H.M.)
| | - El-Maghraby El-Maghraby
- Department of Physics, Faculty of Science, Damanhour University, Damanhur 22511, Egypt; (R.N.); (E.-M.E.-M.); (H.M.)
| | - Hussien Motaweh
- Department of Physics, Faculty of Science, Damanhour University, Damanhur 22511, Egypt; (R.N.); (E.-M.E.-M.); (H.M.)
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Peng WL, Zhang ZP, Rong MZ, Zhang MQ. Reversibly Interlocked Macromolecule Networks with Enhanced Mechanical Properties and Wide pH Range of Underwater Self-Healability. ACS APPLIED MATERIALS & INTERFACES 2020; 12:27614-27624. [PMID: 32468811 DOI: 10.1021/acsami.0c07040] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
A novel strategy for developing homogeneous reversibly interlocking polymer networks (RILNs) with enhanced mechanical properties and underwater self-healing ability is proposed. The RILNs are prepared by the topological reorganization of two preformed cross-linked polymers containing reversible catechol-Fe3+ coordinate bonds and imine bonds and exhibit enhanced mechanical properties, superior underwater self-healing effect within a wide pH range, and water-assisted recycling ability through synergetic action between the reversible catechol-Fe3+ and imine bonds. At higher pH values, the catechol-Fe3+ coordinate bonds are responsible for self-healing, while the imine bonds maintain the stability of the materials. In neutral water, the imine bonds mainly account for self-healing, and hydrogen bonds and entanglements between the two networks prevent the material from collapsing. Under a lower pH value, intermolecular hydrogen bonds and entanglements contribute to self-healing. The outcomes of this work provide a new idea for developing robust multifunctional underwater self-healing materials.
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Affiliation(s)
- Wei Li Peng
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, GD HPPC Lab, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Ze Ping Zhang
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, GD HPPC Lab, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Min Zhi Rong
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, GD HPPC Lab, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Ming Qiu Zhang
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, GD HPPC Lab, School of Chemistry, Sun Yat-Sen University, Guangzhou 510275, P. R. China
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Mahmoud KR, El-Shehawy A, Atta H. Positron annihilation spectroscopy of chain-end-functionalized polystyrenes with definite numbers of benzyl alcohol and perfluorooctyl groups. POLIMEROS 2019. [DOI: 10.1590/0104-1428.04619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Chaos A, Sangroniz A, Gonzalez A, Iriarte M, Sarasua JR, del Río J, Etxeberria A. Tributyl citrate as an effective plasticizer for biodegradable polymers: effect of plasticizer on free volume and transport and mechanical properties. POLYM INT 2018. [DOI: 10.1002/pi.5705] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Ana Chaos
- POLYMAT, Department of Polymer Science and Technology; Faculty of Chemistry, University of the Basque Country UPV/EHU; Donostia Spain
| | - Ainara Sangroniz
- POLYMAT, Department of Polymer Science and Technology; Faculty of Chemistry, University of the Basque Country UPV/EHU; Donostia Spain
| | - Alba Gonzalez
- POLYMAT, Department of Polymer Science and Technology; Faculty of Chemistry, University of the Basque Country UPV/EHU; Donostia Spain
| | - Marian Iriarte
- POLYMAT, Department of Polymer Science and Technology; Faculty of Chemistry, University of the Basque Country UPV/EHU; Donostia Spain
| | - Jose-Ramon Sarasua
- POLYMAT, Department of Mining-Metallurgy Engineering and Materials Science; University of the Basque Country UPV/EHU; Bilbao Spain
| | - Javier del Río
- Departamento de Física de Materiales; Universidad Complutense de Madrid; Madrid Spain
| | - Agustin Etxeberria
- POLYMAT, Department of Polymer Science and Technology; Faculty of Chemistry, University of the Basque Country UPV/EHU; Donostia Spain
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Fong RJ, Robertson A, Mallon PE, Thompson RL. The Impact of Plasticizer and Degree of Hydrolysis on Free Volume of Poly(vinyl alcohol) Films. Polymers (Basel) 2018; 10:polym10091036. [PMID: 30960961 PMCID: PMC6403818 DOI: 10.3390/polym10091036] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 09/07/2018] [Accepted: 09/12/2018] [Indexed: 01/06/2023] Open
Abstract
The effect of plasticizer species and the degree of hydrolysis (DH) on the free volume properties of poly(vinyl alcohol) (PVA) were studied using positron annihilation lifetime spectroscopy. Both glycerol and propylene glycol caused an increase in the free volume cavity radius, although exhibited distinct plasticization behavior, with glycerol capable of occupying existing free volume cavities in the PVA to some extent. The influence of water, normally present in PVA film under atmospheric conditions, was also isolated. Water added significantly to the measured free volume cavity radius in both plasticized and pure PVA matrices. Differences in plasticization behavior can be attributed to the functionality of each plasticizing additive and its hydrogen bonding capability. The increase in cavity radii upon plasticizer loading shows a qualitative link between the free volume of voids and the corresponding reduction in Tg and crystallinity. Cavity radius decreases with increasing DH, due to PVA network tightening in the absence of acetate groups. This corresponds well with the higher Tg observed in the resin with the higher DH. DH was also shown to impact the plasticization of PVA with glycerol, indicating that the larger cavities—created by the weaker hydrogen bonding acetate groups—are capable of accommodating glycerol molecules with negligible effect on the cavity dimensions.
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Affiliation(s)
- Rebecca J Fong
- Department of Chemistry, Durham University, Mountjoy Site, Durham DH1 3LE, UK.
| | - Alexander Robertson
- Department of Chemistry, Durham University, Mountjoy Site, Durham DH1 3LE, UK.
| | - Peter E Mallon
- Department of Chemistry and Polymer Science, University of Stellenbosch, Matieland 7602, Western Cape, South Africa.
| | - Richard L Thompson
- Department of Chemistry, Durham University, Mountjoy Site, Durham DH1 3LE, UK.
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Almalki AS, Alhadhrami A, Adam AMA, Grabchev I, Almeataq M, Al-Humaidi JY, Sharshar T, Refat MS. Preparation of elastic polymer slices have the semiconductors properties for use in solar cells as a source of new and renewable energy. J Photochem Photobiol A Chem 2018. [DOI: 10.1016/j.jphotochem.2018.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Al-Saif FA, Alibrahim KA, Sharshar T, Refat MS. Physicochemical and Spectroscopic Study of Co(II), Ni(II), Cr(III), and Fe(III) Cholyltaurine Adducts. RUSS J GEN CHEM+ 2018. [DOI: 10.1134/s1070363217120362] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Gomes ACDO, Soares BG, Oliveira MG, Machado JC, Windmöller D, Paranhos CM. Characterization of crystalline structure and free volume of polyamide 6/nitrile rubber elastomer thermoplastic vulcanizates: Effect of the processing additives. J Appl Polym Sci 2017. [DOI: 10.1002/app.45576] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | - Bluma G. Soares
- Institute of Macromolecules; Federal University of Rio de Janeiro; Rio de Janeiro Brazil
| | - Marcia G. Oliveira
- Division of Materials Processing and Characterization; National Institute of Technology; Rio de Janeiro Brazil
| | - José C. Machado
- Positron Annihilation Spectroscopy Laboratory, Department of Chemistry; Federal University of Minas Gerais; Belo Horizonte Brazil
| | - Dario Windmöller
- Positron Annihilation Spectroscopy Laboratory, Department of Chemistry; Federal University of Minas Gerais; Belo Horizonte Brazil
| | - Caio M. Paranhos
- Polymer Laboratory, Department of Chemistry; Federal University of São Carlos; São Carlos São Paulo CEP 13565-905 Brazil
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Ningaraju S, Ravikumar HB. Studies on electrical conductivity of PVA/graphite oxide nanocomposites: a free volume approach. JOURNAL OF POLYMER RESEARCH 2016. [DOI: 10.1007/s10965-016-1176-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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11
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Refat MS, Sharshar T, Elsabawy KM, El-Sayed MY, Adam AMA. Synthesis, physicochemical characterization and anticancer screening of sulfa drug ruthenium complexes as anticancer agent. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.07.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Synthesis of amino acid iodine charge transfer complexes in situ methanolic medium: Chemical and physical investigations. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.07.138] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Positron annihilation spectroscopy and mechanical properties studies for epoxy matrices reinforced with different nanoparticles. JOURNAL OF POLYMER RESEARCH 2016. [DOI: 10.1007/s10965-016-1074-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Hassan HE, Refat MS, Sharshar T. Optical and positron annihilation spectroscopic studies on PMMA polymer doped by rhodamine B/chloranilic acid charge transfer complex: Special relevance to the effect of γ-ray irradiation. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2016; 159:238-248. [PMID: 26867205 DOI: 10.1016/j.saa.2016.01.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 01/20/2016] [Accepted: 01/23/2016] [Indexed: 06/05/2023]
Abstract
Polymeric sheets of poly (methylmethaclyerate) (PMMA) containing charge transfer (CT) complex of rhodamine B/chloranilic acid (Rho B/CHA) were synthesized in methanol solvent at room temperature. The systematic analysis done on the Rho B and its CT complex in the form of powder or polymeric sheets confirmed their structure and thermal stability. The IR spectra interpreted the charge transfer mode of interaction between the CHA central positions and the terminal carboxylic group. The polymer sheets were irradiated with 70 kGy of γ radiation using (60)Co source to study the enhanced changes in the structure and optical parameters. The microstructure changes of the PMMA sheets caused by γ-ray irradiation were analyzed using positron annihilation lifetime (PAL) and positron annihilation Doppler broadening (PADB) techniques. The positron life time components (τ(i)) and their corresponding intensities (I(i)) as well as PADB line-shape parameters (S and W) were found to be highly sensitive to the enhanced disorder occurred in the organic chains of the polymeric sheets due to γ-irradiation.
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Affiliation(s)
- H E Hassan
- Cyclotron Facility, Nuclear Research Center, Atomic Energy Authority, Cairo 13759, Egypt.
| | - Moamen S Refat
- Chemistry Department, Faculty of Science, Taif University, P.O. Box 888, Al-Hawiah, Taif 21974, Saudi Arabia; Chemistry Department, Faculty of Science, Port Said University, Port Said, Egypt
| | - T Sharshar
- Physics Department, Faculty of Science, Kafrelsheikh University, Kafr El-Sheikh, Egypt; Physics Department, Faculty of Science, Taif University, P.O. Box 888, Al-Hawiah, Taif 21974, Saudi Arabia
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Prashanth K, Mahesh S, Nanda Prakash M, Munirathnamma L, Ningaraju S, Ravikumar H, Somashekar R, Nagabhushana B. Solution Combustion Synthesis of Cr2O3 Nanoparticles and Derived PVA/Cr2O3 Nanocomposites-Positron Annihilation Spectroscopic Study. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.matpr.2016.11.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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16
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Ismail A, Mahmoud K, Abd-El Salam M. Electrical conductivity and positron annihilation characteristics of ternary silicone rubber/carbon black/TiB2 nanocomposites. POLYMER TESTING 2015; 48:37-43. [DOI: 10.1016/j.polymertesting.2015.09.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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Mahmoud KR, Khodair AI, Shaban SY. Positron annihilation lifetime studies of changes in free volume on some biorelevant nitrogen heterocyclic compounds and their S-glycosylation. Appl Radiat Isot 2015; 105:303-307. [PMID: 26272166 DOI: 10.1016/j.apradiso.2015.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 06/27/2015] [Accepted: 07/01/2015] [Indexed: 11/30/2022]
Abstract
A series of N-heterocyclic compounds was investigated by positron annihilation lifetime spectroscopy as well as Doppler broadening of annihilation radiation (DBAR) at room temperature. The results showed that the formation probability and life time of ortho-positronium in this series are structure and electron-donation character dependent, and can give more information about the structure. The DBAR provides direct information about the change of core and valance electrons as well as the number of defect types present in these compounds.
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Affiliation(s)
- K R Mahmoud
- Physics Department, Faculty of Science, Kafrelsheikh University, 33516 El Gaish Street, Kafr El Sheikh, Egypt.
| | - A I Khodair
- Chemistry Department, Faculty of Science, Kafrelsheikh University, 33516 El Gaish Street, Kafr El Sheikh, Egypt
| | - S Y Shaban
- Chemistry Department, Faculty of Science, Kafrelsheikh University, 33516 El Gaish Street, Kafr El Sheikh, Egypt
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Jeon JW, Zhang L, Lutkenhaus JL, Laskar DD, Lemmon JP, Choi D, Nandasiri MI, Hashmi A, Xu J, Motkuri RK, Fernandez CA, Liu J, Tucker MP, McGrail PB, Yang B, Nune SK. Controlling porosity in lignin-derived nanoporous carbon for supercapacitor applications. CHEMSUSCHEM 2015; 8:428-32. [PMID: 25339600 DOI: 10.1002/cssc.201402621] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 08/11/2014] [Indexed: 05/12/2023]
Abstract
Low-cost renewable lignin has been used as a precursor to produce porous carbons. However, to date, it has not been easy to obtain high surface area porous carbon without activation processes or templating agents. Here, we demonstrate that low molecular weight lignin yields highly porous carbon with more graphitization through direct carbonization without additional activation processes or templating agents. We found that molecular weight and oxygen consumption during carbonization are critical factors to obtain high surface area, graphitized porous carbons. This highly porous carbon from low-cost renewable lignin sources is a good candidate for supercapacitor electrode materials.
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Affiliation(s)
- Ju-Won Jeon
- Energy and Environment Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard, Richland, WA 99354 (USA); Artie McFerrin Department of Chemical Engineering, Texas A&M University, 3122 TAMU, College Station, TX 77843-3122 (USA)
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Ohrt C, Koschine T, Rätzke K, Faupel F, Willner L, Schneider GJ. Free volume in PEP-silica nanocomposites with varying molecular weight. POLYMER 2014. [DOI: 10.1016/j.polymer.2013.11.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Positron annihilation studies of bio-related N2S2-tetradentate ligands and their zinc complexes. Radiat Phys Chem Oxf Engl 1993 2013. [DOI: 10.1016/j.radphyschem.2012.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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22
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Ratna D, Simon GP. Epoxy and hyperbranched polymer blends: Morphology and free volume. J Appl Polym Sci 2010. [DOI: 10.1002/app.31183] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Paranhos CM, Soares BG, Machado JC, Windmöller D, Pessan LA. Microstructure and free volume evaluation of poly(vinyl alcohol) nanocomposite hydrogels. Eur Polym J 2007. [DOI: 10.1016/j.eurpolymj.2007.10.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Machado JC, Silva GG, Oliveira FCD, Lavall RL, Rieumont J, Licinio P, Windmöller D. Free-volume and crystallinity in low molecular weight poly(ethylene oxide). ACTA ACUST UNITED AC 2007. [DOI: 10.1002/polb.21242] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Patrício PSO, Silva GG, Machado JC. Free volume properties of thermoplastic polyurethane/polymethylmethacrylate blends: Evidence of interchain interaction. J Appl Polym Sci 2007. [DOI: 10.1002/app.26317] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Paranhos CM, Soares BG, Oliveira RN, Pessan LA, de Freitas DS, Windmöller D, Machado JC. Microstructural evaluation of poly(vinyl alcohol)-based hydrogels obtained by freezing-thawing technique: Thermal analysis and positron annihilation. J Appl Polym Sci 2007. [DOI: 10.1002/app.26119] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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27
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Mahmoud K, Al-Sigeny S, Sharshar T, El-Hamshary H. Positron annihilation study on free volume of amino acid modified, starch-grafted acrylamide copolymer. Radiat Phys Chem Oxf Engl 1993 2006. [DOI: 10.1016/j.radphyschem.2005.12.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Patrício P, de Sales J, Silva G, Windmöller D, Machado J. Effect of blend composition on microstructure, morphology, and gas permeability in PU/PMMA blends. J Memb Sci 2006. [DOI: 10.1016/j.memsci.2005.06.064] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Reginato AS, Zacca JJ, Secchi AR. Modeling and simulation of propylene polymerization in nonideal loop reactors. AIChE J 2006. [DOI: 10.1002/aic.690491017] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Ribeiro E Silva MES, Machado JC, Mano V, Silva GG. Positron annihilation and differential scanning calorimetry studies of polyacrylamide and poly(dimethylacrylamide)/poly(ethylene glycol) blends. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/polb.10490] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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32
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Queiroz S, Machado J, Porto A, Silva G. Positron annihilation and differential scanning calorimetry studies of plasticized poly(ethylene oxide). POLYMER 2001. [DOI: 10.1016/s0032-3861(00)00668-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Song M, Hourston DJ, Silva GG, Machado JC. Effect of residual water and free volume on the glass-transition temperature and heat capacity in polystyrene/poly(vinyl acetate-co-butyl acrylate) structured latex films. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/polb.1137] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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