Simultaneous enhancement in thermal conductivity and flame retardancy of flexible film by introducing covalent bond connection

2021 ◽  
Vol 421 ◽  
pp. 129729
Author(s):  
Zhencai Qu ◽  
Kunxin Wang ◽  
Chang-an Xu ◽  
Yue Li ◽  
Enxiang Jiao ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Flame Retardancy ◽  
Covalent Bond ◽  
Flexible Film

Green reduction of graphene oxide by polydopamine to a construct flexible film: superior flame retardancy and high thermal conductivity

2017 ◽  
Vol 5 (35) ◽  
pp. 18542-18550 ◽  
Author(s):  
Fubin Luo ◽  
Kun Wu ◽  
Jun Shi ◽  
Xiangxiang Du ◽  
Xiaoya Li ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Graphene Oxide ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Reducing Agent ◽  
High Thermal Conductivity ◽  
Flexible Film

Inspired by mussels, dopamine (DOPA) was used as a green reducing agent for graphene oxide (GO) to prepare a superior flame retardant and high thermal conductive flexible film.

The flexible film of SCF/BN/PDMS composites with high thermal conductivity and electrical insulation

2021 ◽  
Vol 23 ◽  
pp. 100573
Author(s):  
Houbao Liu ◽  
Xinqing Su ◽  
Renli Fu ◽  
Binyong Wu ◽  
Xudong Chen
Keyword(s):  
Thermal Conductivity ◽  
Electrical Insulation ◽  
High Thermal Conductivity ◽  
Flexible Film

Multiple synergistic effects of graphene-based hybrid and hexagonal born nitride in enhancing thermal conductivity and flame retardancy of epoxy

2020 ◽  
Vol 379 ◽  
pp. 122402 ◽  
Author(s):  
Yuezhan Feng ◽  
Gaojie Han ◽  
Bo Wang ◽  
Xingping Zhou ◽  
Jianmin Ma ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Flame Retardancy ◽  
Synergistic Effects

scholarly journals Effects of Tung Oil-Based Polyols on the Thermal Stability, Flame Retardancy, and Mechanical Properties of Rigid Polyurethane Foam

Polymers ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 45 ◽  
Author(s):  
Wei Zhou ◽  
Caiying Bo ◽  
Puyou Jia ◽  
Yonghong Zhou ◽  
Meng Zhang
Keyword(s):  
Thermal Stability ◽  
Polyurethane Foam ◽  
Flame Retardancy ◽  
Covalent Bond ◽  
Rigid Polyurethane Foam ◽  
Limiting Oxygen Index ◽  
Sem Micrographs ◽  
Tung Oil ◽  
Char Layer ◽  
Ring Opening Reaction

A phosphorus-containing tung oil-based polyol (PTOP) and a silicon-containing tung oil-based polyol (PTOSi) were each efficiently prepared by attaching 9,10-dihydro-9-oxa-10-phosphaphenanthrene (DOPO) and dihydroxydiphenylsilane (DPSD) directly, respectively, to the epoxidized monoglyceride of tung oil (EGTO) through a ring-opening reaction. The two new polyols were used in the formation of rigid polyurethane foam (RPUF), which displayed great thermal stability and excellent flame retardancy performance. The limiting oxygen index (LOI) value of RPUF containing 80 wt % PTOP and 80 wt % PTOSi was 24.0% and 23.4%, respectively. Fourier transfer infrared (FTIR), Nuclear Magnetic Resonance (NMR) and thermogravimetric (TG) analysis revealed that DOPO and DPSD are linked to EGTO by a covalent bond. Interestingly, PTOP and PTOSi had opposite effects on Tg and the compressive strength of RPUF, where, with the appropriate loading, the compressive strengths were 0.82 MPa and 0.25 MPa, respectively. At a higher loading of PTOP and PTOSi, the thermal conductivity of RPUF increased while the RPUF density decreased. The scanning electron microscope (SEM) micrographs showed that the size and closed areas of the RPUF cells were regular. SEM micrographs of the char after combustion showed that the char layer was compact and dense. The enhanced flame retardancy of RPUF resulted from the barrier effect of the char layer, which was covered with incombustible substance.

Study and Application of Plastic Construction Materials

2011 ◽  
Vol 99-100 ◽  
pp. 1117-1120 ◽  
Author(s):  
Mao Quan Xue
Keyword(s):  
Thermal Conductivity ◽  
Corrosion Resistance ◽  
Energy Saving ◽  
Thermal Insulation ◽  
Flame Retardancy ◽  
Building Materials ◽  
Construction Materials ◽  
Low Thermal Conductivity ◽  
Building Walls

As new building materials, plastic has light weigh, corrosion resistance, low thermal conductivity, thermal insulation, waterproof, energy-saving, molding convenient, high recycling characteristic, widely used in building materials. According to the research of improving its flame retardancy, strength, thermal insulation, waterproof properties, the application of plastic use in doors and windows, pipeline, building walls and roofs of buildings, etc. were reviewed, and the developing direction was discussed.

Structural Characteristics and Quantum Chemistry Calculation of Si-Doped Boron Carbides

1998 ◽  
Vol 538 ◽  
Author(s):  
Min Xinmin ◽  
Nan Cewen ◽  
Cai Kefeng
Keyword(s):  
Thermal Conductivity ◽  
Electrical Conductivity ◽  
Boron Carbide ◽  
Thermoelectric Properties ◽  
Structural Unit ◽  
Structural Characteristics ◽  
Covalent Bond ◽  
Discrete Variation ◽  
Chemistry Calculation ◽  
Si Doped

AbstractStructural characteristics, chemical bonds and thermoelectric properties of Si-doped boron carbides are studied through calculations of various structural unit models by using a self-consistent-field discrete variation Xα method. The calculations show that Si atom doped in boron carbide is in preference to substituting B or C atoms on the end of boron carbide chain, and then may occupy interstitial sites, but it is difficult for Si to substitute B or C atom in the centers of chain or in the icosahedra. A representative structural unit containing a Si atom is [C-B-Si]ε+ [B11C]ε-, while the structural unit without Si is [C-B-B(C)]δ--[B11C]δ+, and the coexistence of these two different structural units makes the electrical conductivity increases. As the covalent bond of Si-B or Si-C is weaker than that of B-B or B-C, the thermal conductivity decreases when Si is added into boron carbides. With the electrical conductivity increases and the thermal conductivity decreases, Si doping has significant effect on thermoelectric properties of boron carbides.

Effect of Nanoclay on the Physical-Mechanical and Thermal Properties and Microstructure of Extruded Noncross-Linked LDPE Nanocomposite Foams

2011 ◽  
Vol 471-472 ◽  
pp. 751-756 ◽  
Author(s):  
F. Zandi ◽  
M. Rezaei ◽  
A. Kasiri
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Cell Size ◽  
Flame Retardancy ◽  
Image Analyzer ◽  
Mechanical And Thermal Properties ◽  
Average Cell Size ◽  
Cell Size Distribution ◽  
Average Cell ◽  
Nanocomposite Foams

Novel noncross-linked low density polyethylene (LDPE) foams were produced by extrusion process. In this study the effects of Organophilic Montmorillonite (OMMT) nanoclay (DK1) on thermal conductivity, flame retardancy, morphological and mechanical properties of LDPE foams have been investigated. Nanoclay dispersion in LDPE foam structure was examined by X-ray diffraction (XRD), microstructure was observed by an optical microscope and analyzed by Bel View image analyzer, thermal conductivity was studied by a simple transient method, mechanical properties was investigated using a tensile-compression Zwick-Roell machine as well as the flame retardancy of the samples was examined by flammability test. The optimum nanoclay content was determined by comparison of the properties in nanocomposite and neat LDPE foams. Due to the presence of nanoclay in the foam and decreasing the cell nucleation energy around the nanoclay, the average cell size was decreased as well as the cell density and microstructure uniformity was increased. In XRD patterns of LDPE nanocomposite foams, OMMT (DK1) characteristic peak was not observed as evidence of nanoclay intercalation-exfoliation in the polymer matrix, which led to the production of foams with homogenous microstructure. Furthermore, this nanocomposites showed lower thermal conductivity compared to neat LDPE foam, which can be attributed to the cell size reduction as well as narrow cell size distribution in nanocomposite foams. Compression test results demonstrated that LDPE nanocomposite foams with proper clay contents have improved mechanical properties (Young’s modulus, compressive strength). Furthermore due to the presence of DK1 nanoclay, LDPE foam showed a good char formation as an evidence of their flame retardancy.

Enhanced thermal conductivity and flame retardancy of polyamide 6/flame retardant composites with hexagonal boron nitride

2018 ◽  
Vol 38 (8) ◽  
pp. 767-774 ◽  
Author(s):  
Liang Wang ◽  
Luchong Zhang ◽  
Andreas Fischer ◽  
Yuhua Zhong ◽  
Dietmar Drummer ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Boron Nitride ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
High Performance ◽  
Heat Dissipation ◽  
Hexagonal Boron Nitride ◽  
Light Emitting Diode ◽  
Polyamide 6 ◽  
Twin Screw

Abstract High performance composite of polyamide 6 (PA6)/flame retardant (FR)/hexagonal boron nitride (hBN) was prepared via twin screw extrusion, followed by injection molding. The heat dissipation of the composite was significantly improved by incorporating 40 vol% of hBN, and the corresponding thermal conductivity was up to 5.701 W/(m·K), nearly 17 times that of the PA6/FR composites. In addition, the combination effect of hBN and FR to the flame retardancy of the composites was observed, and the addition of hBN could dramatically enhance the flame retardancy of composites, achieving a UL94 V-0 rating with a limited oxygen index (LOI) value of 37%. This multifunctional modification would broaden the application field of PA6 composites in light-emitting diode (LED) lamps, electronic products, and so on.

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