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Necolau MI, Bălănucă B, Frone AN, Radu IN, Grădişteanu-Pîrcălăbioru G, Damian CM. Combined Thermomechanical Effect of Graphene Oxide and Montmorillonite on Biobased Epoxy Network Formation for Coatings. ACS OMEGA 2024; 9:8297-8307. [PMID: 38405461 PMCID: PMC10882706 DOI: 10.1021/acsomega.3c09059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 12/30/2023] [Accepted: 01/05/2024] [Indexed: 02/27/2024]
Abstract
Epoxy nanocomposites derived from linseed oil, reinforced with graphene oxide (GO) and montmorillonite (MMT) nanostructures, were synthesized. The nanohybrids were developed by enriching the structure of MMT and GO with primary amines through a common and simplified method, which implies physical interactions promoted by ultrasonic processing energy. The influence of the new nanoreinforcing agents along with neat ones on the overall properties of the biobased epoxy materials for coating applications was assessed. Interface formation through surface compatibility was contained by the lower values of activation energy calculated from differential scanning calorimetry (DSC) curves, along with a consistent 70% increase in the cross-linking density when amine-modified MMT was used. Thermomechanical characteristics of the biobased epoxy nanocomposites were explained through the interaction of the functional groups over the curing process of epoxidized linseed oil (ELO), giving a 15 °C higher Tg value increase. Furthermore, the low surface energy values suggested an intrinsic antibacterial activity, as proved by a significant decrease of CFU against Staphylococcus aureus bacterial strains on the 0.25% reinforced coatings.
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Affiliation(s)
- Mădălina Ioana Necolau
- Advanced Polymer Materials Group, National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu Street, Bucharest 011061, Romania
| | - Brînduşa Bălănucă
- Advanced Polymer Materials Group, National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu Street, Bucharest 011061, Romania
- Department of Organic Chemistry "C. Nenitescu", National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu Street, Bucharest 011061, Romania
| | - Adriana Nicoleta Frone
- National Institute for Research & Development in Chemistry and Petrochemistry - ICECHIM, 202 Spl. Independentei, Bucharest 060021, Romania
| | - Iulia Nicoleta Radu
- Advanced Polymer Materials Group, National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu Street, Bucharest 011061, Romania
| | - Graţiela Grădişteanu-Pîrcălăbioru
- eBio-hub Research-Center, National University of Science and Technology Politehnica Bucharest, 6 Iuliu Maniu Boulevard, Campus Building, Bucharest 061344, Romania
- Research Institute of University of Bucharest, University of Bucharest, Bucharest 050095, Romania
- Academy of Romanian Scientists, 54 Splaiul Independentei, Bucharest 050094, Romania
| | - Celina Maria Damian
- Advanced Polymer Materials Group, National University of Science and Technology Politehnica Bucharest, 1-7 Gh. Polizu Street, Bucharest 011061, Romania
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Branda F, Passaro J, Pauer R, Gaan S, Bifulco A. Solvent-Free One-Pot Synthesis of Epoxy Nanocomposites Containing Mg(OH) 2 Nanocrystal-Nanoparticle Formation Mechanism. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:5795-5802. [PMID: 35482845 PMCID: PMC9097534 DOI: 10.1021/acs.langmuir.2c00377] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Epoxy nanocomposites containing Mg(OH)2 nanocrystals (MgNCs, 5.3 wt %) were produced via an eco-friendly "solvent-free one-pot" process. X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and thermogravimetric analysis (TGA) confirm the presence of well-dispersed MgNCs. HRTEM reveals the presence also of multisheet-silica-based nanoparticles and a tendency of MgNCs to intergrow, leading to complex nanometric structures with an intersheet size of ∼0.43 nm, which is in agreement with the lattice spacing of the Mg(OH)2 (001) planes. The synthesis of MgNCs was designed on the basis of a mechanism initially proposed for the preparation of multisheet-silica-based/epoxy nanocomposites. The successful "in situ" generation of MgNCs in the epoxy via a "solvent-free one-pot" process confirms the validity of the earlier disclosed mechanism and thus opens up possibilities of new NCs with different fillers and polymer matrix. The condition would be the availability of a nanoparticle precursor soluble in the hydrophobic resin, giving the desired phase through hydrolysis and polycondensation.
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Affiliation(s)
- Francesco Branda
- Department
of Chemical Materials and Industrial Production Engineering (DICMaPI), University of Naples Federico II, 80125 Naples, Italy
| | - Jessica Passaro
- Department
of Chemical Materials and Industrial Production Engineering (DICMaPI), University of Naples Federico II, 80125 Naples, Italy
| | - Robin Pauer
- Advanced
Materials and Surfaces Fibers, Empa Swiss
Federal Laboratories for Materials Science and Technology, CH-8600 Dubendorf, Switzerland
| | - Sabyasachi Gaan
- Laboratory
for Advanced Fibers, Empa Swiss Federal
Laboratories for Materials Science and Technology, Lerchenfeldstrasse 5, 9014 St. Gallen, Switzerland
| | - Aurelio Bifulco
- Department
of Chemical Materials and Industrial Production Engineering (DICMaPI), University of Naples Federico II, 80125 Naples, Italy
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