scholarly journals Liquid-Crystal and Fire-Retardant Properties of New Hexasubstituted Cyclotriphosphazene Compounds with Two Schiff Base Linking Units

Molecules ◽  
2020 ◽  
Vol 25 (9) ◽  
pp. 2122 ◽  
Author(s):  
Zuhair Jamain ◽  
Melati Khairuddean ◽  
Tay Guan-Seng
Keyword(s):  
Schiff Base ◽  
Liquid Crystal ◽  
Polyester Resin ◽  
Fire Retardant ◽  
Terminal Group ◽  
Scanning Calorimetry ◽  
Limiting Oxygen Index ◽  
Crystal Properties ◽  
Fire Retardant Properties ◽  
Good Agreement

A series of new hexasubstituted cyclotriphosphazene compounds (4a–j) consisting of two Schiff base linking units and different terminal substituents was successfully synthesized and characterized. The structures of these compounds were confirmed using Fourier Transform Infra-Red (FTIR), Nuclear Magnetic Resonance (NMR), and CHN elemental analysis. Polarized optical microscopy (POM) was used to determine their liquid-crystal behavior, which was then further confirmed using differential scanning calorimetry (DSC). Compounds 4a–i with heptyl, nonyl, decyl, dodecyl, tetradecyl, hydroxy, 4-carboxyphenyl, chloro, and nitro terminal ends, respectively, showed the liquid-crystal properties, whereas compound 4j with the amino group was found to be non-mesogenic. The attachment of an electron-donating group in 4j eventually give a non-mesogenic product. The study of the fire-retardant properties of these compounds was done using the limiting oxygen index (LOI). In this study, polyester resin (PE) was used as a matrix for moulding, and the LOI value of pure PE was 22.53%. The LOI value increased to 24.71% when PE was incorporated with 1 wt.% of hexachlorocyclotriphosphazene (HCCP), thus indicating that HCCP has a good fire-retardant properties. The result showed that all the compounds have good agreement in their LOI values. Compound 4i with a nitro terminal group gave the highest LOI value of 28.37%.

scholarly journals Synthesis and Determination of Thermotropic Liquid Crystalline Behavior of Cinnamaldehyde-Based Molecules with Two Schiff Base Linking Units

Molecules ◽  
2020 ◽  
Vol 25 (17) ◽  
pp. 3780
Author(s):  
Zuhair Jamain ◽  
Nor Faizawani Omar ◽  
Melati Khairuddean
Keyword(s):  
Schiff Base ◽  
Liquid Crystal ◽  
Nematic Phase ◽  
Liquid Crystalline ◽  
Condensation Reaction ◽  
Structure Property ◽  
Scanning Calorimetry ◽  
Crystal Properties ◽  
Structure Property Relationship

A series of liquid crystal molecules with two Schiff base linking units and a cinnamaldehyde core with different terminal groups were synthesized and characterized. The intermediates of 4-heptyloxybenzaldehyde (1a) and 4-dodeyloxybenzaldehyde (1b) were synthesized through the alkylation of 4-hydroxybenzaldehyde with a series of bromoalkane. A condensation reaction of cinnamaldehyde, 1,4-phenylenediamine and a series of substituted benzaldehydes with different terminal groups such as bromo, chloro, hydroxy, cinnamaldehyde, hydrogen, methoxy, heptyloxy and dodecyloxy produced a series of new cinnamaldehyde-based compounds, 2–9, respectively. All these compounds were characterized using Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and CHN elemental analysis. The liquid crystal properties of these compounds were determined using polarized optical microscopy (POM), and their transitions were further confirmed using differential scanning calorimetry (DSC). Compounds with chloro, bromo, methoxy, heptyloxy, and dodecyloxy substituents are mesogenic compounds with nematic phase behavior. However, the other compounds were found to be non-mesogenic without any mesophase transitions. The structure–property relationship was investigated in order to study the effect of different terminal groups and Schiff base linking units on the liquid crystalline behavior of these compounds.

Preparation and Properties of Recycled-Polyester Nanocomposite Fibers Synergistic Modified with Phosphorus Containing Flame-Retardant and α-Zirconium Phosphate

2014 ◽  
Vol 789 ◽  
pp. 174-177 ◽  
Author(s):  
Zhi Hao Wu ◽  
Li Li Li ◽  
Shuai Shuai Jiang ◽  
Ze Xu Hu ◽  
Yu Chen Mao ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Melt Spinning ◽  
Zirconium Phosphate ◽  
Oxygen Index ◽  
Fire Retardant ◽  
Limiting Oxygen Index ◽  
Phosphorus Containing ◽  
Fire Retardant Properties ◽  
Nanocomposite Fibers ◽  
Positive Effect

Recycled-polyester (RPET) was melt blended with the phosphorus-containing flame retardant (FRP) and α-zirconium phosphate (α-ZrP). The thermal properties of RPET/FRP/α-ZrP composites were analyzed. Modified RPET fibers were prepared through melt spinning of dried RPET nanocomposite chips. The mechanical properties and fire-retardant properties of RPET/FRP/α-ZrP fibers containing different α-ZrP contents were tested. The results show that the synergism of α-ZrP and FRP exerts a positive effect on the mechanical and the flame-retardant property of RPET, leading to nanocomposite fibers of 1.9cN/dtex and 31.6% limiting oxygen index (LOI) value.

scholarly journals Effects of nitrogen-phosphorus flame retardants in different forms on the performance of slim-type medium-density fiberboard

BioResources ◽  
2017 ◽  
Vol 12 (4) ◽  
pp. 8014-8029
Author(s):  
Bin Xu ◽  
Weidong Li ◽  
Daowu Tu ◽  
Zhinan Wu ◽  
Changjie Song
Keyword(s):  
Flame Retardants ◽  
Mechanical Performance ◽  
Orthogonal Design ◽  
Medium Density Fiberboard ◽  
Wood Fiber ◽  
Fire Retardant ◽  
National Standard ◽  
Medium Density ◽  
Scanning Calorimetry ◽  
Limiting Oxygen Index

An orthogonal design was used to optimize the process of making slim medium-density fiberboard modified by a nitrogen-phosphorous series of flame retardants. Mechanical performance was the evaluating criterion. Subsequently, the combustion performances of each type of flame retardant, including in states solid, liquid, and their combination with a ratio of 1:1, were investigated to clarify the corresponding fire-retardant mechanism. The results showed that only physical bonding was responsible for connecting the wood fiber with the retardants, according to the Fourier transform infrared spectrum. Catalytic charring, flame retardancy, and the thermal insulation of three types of retardant were solidified by the results of a cone calorimeter (CONE) analysis, thermogravimetric (TG) analysis, and differential scanning calorimetry (DSC), and the mixture of solid and liquid was demonstrated as the primary choice. It was also found that after the mixture of the solid and liquid retardant was added, the limiting oxygen index of the board reached 43.3%, and it met the requirements of the B1 Class in the Chinese National Standard GB/T8624-2012 (2012).

Synthesis and Liquid Crystal Properties of a New Organometallic Palladium Complex

2011 ◽  
Vol 306-307 ◽  
pp. 242-245
Author(s):  
Jian Qiang Liu ◽  
Xing Qi Fu ◽  
Jian Ye Song ◽  
Yun Xu Fu ◽  
Xing Cheng Zhang ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Optical Microscope ◽  
Resonance Spectroscopy ◽  
Functional Material ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Liquid Crystallinity ◽  
Crystal Properties ◽  
New Type ◽  
Clearing Temperature

A new organometallic palladium coordinated liquid crystal that was written by PdS6 had been synthesized by chelating reaction of the tetrachloropalladate (PdCl42-) and the star-like liquid crystal (S6) containing four hexyloxyazobenzene mesogens in its periphery. The structure and liquid crystallinity (LC) of PdS6 were characterized by infrared absorption spectroscopy (IR), ultraviolet absorption spectra (UV), nuclear magnetic resonance spectroscopy (NMR), elemental analysis (EA), polarizing optical microscope (POM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The phase behavior of PdS6 was Cr155N230I205N160Cr, its melting point and clearing temperature were higher than those of the free azo ligand S6, its mesophase range wass broader than S6’s. It will be used as a new type photoelectric functional material in the future.

Coating of lightweight wool fabric with nano clay for fire retardancy

2019 ◽  
Vol 110 (5) ◽  
pp. 764-770 ◽  
Author(s):  
Seiko Jose ◽  
Nachimuthu Shanmugam ◽  
Sekhar Das ◽  
Ajay Kumar ◽  
Pintu Pandit
Keyword(s):  
Oxygen Index ◽  
Fire Retardant ◽  
Wool Fabric ◽  
Limiting Oxygen Index ◽  
Analytical Instruments ◽  
Flammability Test ◽  
Nano Clay ◽  
Fire Retardant Properties ◽  
In Fire

Nano-kaolinite was applied to lightweight wool fabric for imparting fire retardant finish using pad batch as well as exhaust method. The effect of fire retardant treatments on the physico-mechanical properties of wool fabric was studied in detail. Nano-kaolinite incorporated fire retardant formulations showed high fire retardant performance in terms of inclined flammability test, limiting oxygen index (LOI) and thermogravimetric analysis. The characterization of nanoparticles was performed using various analytical instruments. The results inferred that nano-kaolinite treatment by both application methods is effective for improving the fire resistance of wool fabric. The treatment resulted up to 32% enhancement in fire retardant properties.

Determination of chemical structure, mechanical properties and combustion resistance of polyurethane doped with boric acid

2021 ◽  
pp. 089270572110194
Author(s):  
Ali Ihsan Kaya
Keyword(s):  
Surface Morphology ◽  
Boric Acid ◽  
Electromagnetic Interference ◽  
Cell Structure ◽  
Chemical Properties ◽  
Fire Retardant ◽  
Combustion Products ◽  
Shielding Effectiveness ◽  
Scanning Calorimetry ◽  
Limiting Oxygen Index

The low fire resistance property of pristine polyurethane (PU) restricts its areas of usage in domestic applications and especially in the furniture industry. Therefore, PU based materials should be non-flammable besides having favorable mechanical and chemical properties. In this study, boric acid (BA) was added to the polyurethane foam as fire retardant. The effect of amount of BA (5%, 10%, and 15% (w/w)) on fire retardancy was examined. The thermal properties and the surface morphology of the structures were investigated. The amount of BA affected surface morphology. It was observed that BA affects the density and compressive strength in three directions with the physical change it causes in the cell structure. In the X-ray diffraction analysis of the unmodified hard polyurethane and the hard polyurethanes containing BA at different amounts (5%, 10%, and 15% (w/w)), the peaks were observed to appear in three different groups. The thermal stability of the rigid PU treated with BA was investigated via thermogravimetric analysis and the limiting oxygen index (LOI) analysis. The electromagnetic interference shielding effectiveness (EMI SE) was measured via a system consisting of two anechoic boxes and receiving and transmitting antennas. Four different temperature zones were observed when examining the thermal behavior via differential scanning calorimetry. Single source flame test, UL94 test and cone calorimeter tests were performed to determine the ignition property of BA doped PU. It was determined that BA is a better fire retardant than other chemicals also for the low toxicity of the combustion products formed.

Study of the Behavior of the Fire-Retardant Seals Under Thermal Exposure

2021 ◽  
pp. 52-57
Author(s):  
T.A. Budykina ◽  
◽  
E.B. Anosova ◽  
Keyword(s):  
Fire Protection ◽  
Experimental Studies ◽  
Fire Retardant ◽  
Fire Risk ◽  
Thermal Exposure ◽  
Scanning Calorimetry ◽  
Fire Retardant Properties ◽  
Significant Temperature ◽  
Temperature Loads ◽  
Temperature Heating

The results are presented concerning the experimental studies of the behavior of fire-retardant seals produced by the Ogneza group of companies under thermal exposure up to 1000 °C, obtained by the method of synchronous thermal analysis (thermogravimetry together with the differential scanning calorimetry). Incombustible properties of the M-СORE (NG) seal were confirmed, which showed a decrease in the mass of the material when heated to 1000 °C by 11%, which is due to the mineral composition of the sample (a silica-based material). High thermal stability was shown by the fire-fighting seal M-CORE, the decrease in the mass of the sample of which, after reaching a temperature of 555 °C, stops at 37 %, which indicates the formation of an ash residue. Thermal sealing tape LTU, as a result of the temperature heating starting from a mark of 192 °C, uniformly was losing mass up to a total value of 82 %. The experiment established the sealant swelling. According to the experimental data obtained, the samples M-CORE (NG) confirmed the fire-retardant properties declared by the manufacturer. For the selection of heat-resistant materials that can withstand significant temperature loads during the operation of units and mechanisms, for electrical and thermal insulation, for fire protection of air ducts, equipment, structures, the advantages, and reliability of these seals are obvious. The results of the study (the temperature of the beginning of an intensive decrease in mass, the temperature of the onset of thermal effects accompanying a decrease in mass, the behavior of materials under thermal exposure) can be considered when designing heat and electrical insulation, fire protection of production processes, as well as when determining the level of fire risk of the production facilities.

scholarly journals An unsymmetrical porphyrin and its metal complexes: Synthesis, spectroscopy, thermal analysis and liquid crystal properties

2009 ◽  
Vol 74 (10) ◽  
pp. 1097-1104 ◽  
Author(s):  
Changfu Zhuang ◽  
Xuexin Tang ◽  
Dong Wang ◽  
Aiqing Xia ◽  
Wenhui Lian ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Liquid Crystalline ◽  
Thermal Studies ◽  
Luminescent Properties ◽  
Quantum Yields ◽  
Scanning Calorimetry ◽  
Crystal Properties

The synthesis and characterization of a new unsymmetrical porphyrin liquid crystal, 5-(4-stearoyloxyphenyl)phenyl-10,15,20-triphenylporphyrin (SPTPPH2) and its transition metal complexes (SPTPPM, M(II) = Zn, Fe, Co, Ni, Cu or Mn) are reported. Their structure and properties were studied by elemental analysis, and UV-Vis, IR, mass and 1H-HMR spectroscopy. Their luminescent properties were studied by excitation and emission spectroscopy. The quantum yields of the S1 ? S0 fluorescence were measured at room temperature. According to thermal studies, the complexes have a higher thermal stability (no decomposition until 200?C). Differential scanning calorimetry (DSC) data and an optical textural photograph, obtained using a polarizing microscope (POM), indicate that the porphyrin ligand had liquid crystalline character and that it exhibited more than one mesophase and a low-lying phase transition temperature, with transition temperatures of 19.3 and 79.4?C; the temperature range of the liquid crystal (LC) phase of the ligand was 70.1?C.

Synthesis and Mesophases Study on 2-(8-bromooctanoic acid ester)-3,6,7,10,11-penta-pentyloxytriphenylene

2011 ◽  
Vol 181-182 ◽  
pp. 156-159 ◽  
Author(s):  
Ming Xia Zhang ◽  
Chun Xiu Zhang ◽  
Jia Ling Pu ◽  
Hao Wu ◽  
Gui Sen Fang
Keyword(s):  
Liquid Crystal ◽  
Acid Ester ◽  
Carrier Transport ◽  
Scanning Calorimetry ◽  
Discotic Liquid Crystal ◽  
Crystal Properties ◽  
Ft Ir ◽  
Transport Mobility ◽  
Different Scanning Calorimetry ◽  
Crystal Compound

A novel triphenylene-based discotic liquid crystal compound 2-(8-bromooctanoic acid ester)-3,6,7,10,11-penta-pentyloxytriphenylene was synthesized in this study.The chemical structure of the compound was characterized by1HNMR spectra, FT-IR spectra and we confirmed its structure. The mesophases were investigated by using different scanning calorimetry DSC and polarizing optical microscopy POM, the results showed that the target product had Liquid crystal properties and the temperature range of 90-101 °C, and showed a clear columnar phase. The carrier transport mobility was measured using time-of-flight TOF method, μ=1.09*10-2cm2V-1s-1.

Development of a flame retardant chemical for finishing of cotton, polyester, and CO/PET blends

2018 ◽  
Vol 49 (2) ◽  
pp. 141-161 ◽  
Author(s):  
Raziye Atakan ◽  
Azize Bical ◽  
Ebru Celebi ◽  
Gulay Ozcan ◽  
Neda Soydan ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Chemical Structure ◽  
Polyester Resin ◽  
Oxygen Index ◽  
Impregnation Method ◽  
Scanning Calorimetry ◽  
Limiting Oxygen Index ◽  
System A ◽  
Flammability Test ◽  
Flammability Characteristics

A novel polymeric flame retardant with phosphorous–nitrogen synergism (PVP (PR)-P-DCDA) was synthesized by polyvinyl alcohol, hydrophilic polyester resin, phosphoric acid, and dicyandiamide. 100% polyester, 100% cotton, and 50/50% cotton–polyester blended fabrics were treated with PVP (PR)-P-DCDA by impregnation method. Flammability characteristics, thermal decomposition, surface morphology, and chemical structure of treated and untreated fabrics were investigated by vertical flammability test, limiting oxygen index, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, and Fourier-transform infrared, respectively. Results showed that PVP (PR)-P-DCDA is an eco-friendly flame retardant system, a good char-forming flame retardant agent with superior ease of application for cotton, polyester, and cotton/polyester blends. At the industrial scale, the flame retardant agent PVP (PR)-PDCDA has been commercialized under the name Fire-off EBR.

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