Xiangbin Zhang, Lang Xu, Qing Sun, Jian Zhang, Jiawei Sheng
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引用次数: 0
Abstract
Ceramic polyolefin composites have the capability to transform into hard ceramics when exposed to fire conditions. During the ceramization process, the formation of new crystalline phase plays a crucial role in enhancing flame‐retardant and ceramifiable properties. Consequently, ceramic polyolefin composites show great potential for the applications in fire‐resistant wires and cables. In this article, the incorporation of the compound flame retardant consisting of ammonium polyphosphate/melamine cyanurate/zinc borate (APP/MCA/ZB) was found to enhance the flame retardancy and ceramization of polyethylene/wollastonite fiber/phosphate glass frits (PE/WF/PGF) composites. The results indicated that ceramifiable flame‐retarding PE composites with compound flame retardant exhibited superior flame retardancy compared to pure PE and PE composites with a single flame retardant. Specifically, the limiting oxygen index (LOI) was significantly increased to 26.8%, and the vertical combustion test rating in UL‐94 (test for flammability of plastic materials for parts in devices and appliances) reached V‐0. During the heating process, ZB thermally decomposed to produce 2ZnO ⋅ 3B2O3, which reacted with CaSiO3 to form a silicate glass intermediate phase (CaO ⋅ SiO2 ⋅ 2ZnO ⋅ 3B2O3). APP thermally decomposed to produce (HPO3)n, which reacted with 2ZnO ⋅ 3B2O3 to form a phosphate glass intermediate phase (nP2O5 ⋅ 2ZnO ⋅ 3B2O3). These two glass phases experienced a eutectic reaction with WF, ultimately producing the formation of a new crystalline phase of calcium zinc phosphate (CZP, Ca19Zn2(PO4)14). This newly formed CZP phase made sintered ceramics more compact and had higher flexural strength. The flexural strength of ceramic residues after sintering was 11.68 MPa, meeting the requirements for practical applications.
期刊介绍:
Polymers for Advanced Technologies is published in response to recent significant changes in the patterns of materials research and development. Worldwide attention has been focused on the critical importance of materials in the creation of new devices and systems. It is now recognized that materials are often the limiting factor in bringing a new technical concept to fruition and that polymers are often the materials of choice in these demanding applications. A significant portion of the polymer research ongoing in the world is directly or indirectly related to the solution of complex, interdisciplinary problems whose successful resolution is necessary for achievement of broad system objectives.
Polymers for Advanced Technologies is focused to the interest of scientists and engineers from academia and industry who are participating in these new areas of polymer research and development. It is the intent of this journal to impact the polymer related advanced technologies to meet the challenge of the twenty-first century.
Polymers for Advanced Technologies aims at encouraging innovation, invention, imagination and creativity by providing a broad interdisciplinary platform for the presentation of new research and development concepts, theories and results which reflect the changing image and pace of modern polymer science and technology.
Polymers for Advanced Technologies aims at becoming the central organ of the new multi-disciplinary polymer oriented materials science of the highest scientific standards. It will publish original research papers on finished studies; communications limited to five typewritten pages plus three illustrations, containing experimental details; review articles of up to 40 pages; letters to the editor and book reviews. Review articles will normally be published by invitation. The Editor-in-Chief welcomes suggestions for reviews.