Preparation and Properties of Silicon-Modified Polynaphthalimides

1997 ◽  
Vol 9 (2) ◽  
pp. 135-143 ◽  
Author(s):  
Yasuharu Yamada ◽  
Nobuyuki Furukawa
Keyword(s):  
Thin Films ◽  
Thermal Stability ◽  
Molecular Weight ◽  
Thermal Decomposition ◽  
Silicon Content ◽  
Polymer Structure ◽  
Decomposition Temperature ◽  
Low Molecular Weight ◽  
Thermal Decomposition Temperature ◽  
Aromatic Diamines

Silicon-modified polynaphthalimides derived from 1,4,5,8-naphthalenetetracar-boxylic dianhydride, 4,4′-dinaphthalic anhydride and bis(1, 8-dicarboxynaphth-4-yl)dimethyl silane dianhydride and several types of aromatic diamines were prepared and their thermal stability was studied. The monomers of 4, 4′-dinaphthalic anhydride and bis(1, 8-dicarboxynaphth-4-yl)dimethyl silane dianhydride were also synthesized from acenaphthene followed by oxidation. Polyimides obtained were brittle because of the low molecular weight and the rigidity of the polymer structure. Therefore, no good thin films were made from the polyimides (the colour of which was dark brown). The imidization of polynaphthalimide occurred in the temperature range of 100–200 °C which is lower by about 50 °C than that of polypyromellitimide. The polyimides having a naphthalimide structure showed higher thermal decomposition temperature than the polyimides having a pyromellitimide structure derived from pyromellitic dianhydride. However, the decomposition temperature of silicon-modified polynaphthalimides decreased with increasing silicon content in the polyimides.

Studies on Thermal Stability and Rheological Property of PU/PVDF Blend

2011 ◽  
Vol 311-313 ◽  
pp. 1065-1070
Author(s):  
Guo Lan Huan ◽  
Jian Li Liu ◽  
Qi Yun Du ◽  
Xiao Yu Hu
Keyword(s):  
Activation Energy ◽  
Thermal Stability ◽  
Thermal Decomposition ◽  
Shear Stress ◽  
Rheological Property ◽  
Decomposition Temperature ◽  
Dynamic Equations ◽  
Thermal Decomposition Temperature ◽  
Thermal Stability Of ◽  
Decomposition Activation Energy

In this article, the thermal stability of PU/PVDF blend was investigated by thermogravimetry (TG), and their rheological property was studied through testing and analyzing the rheological curves. The results showed that, with the increase in PVDF content, the thermal decomposition temperature of PU/PVDF blend increased, and by fitting relevant data to thermal decomposition dynamic equations, it was found that thermal decomposition activation energy of the blend increased gradually, i.e. the thermal stability of the blend increased gradually. Meantime, based on the curves of shear stress vs. shear rate of the blend at 180°C and 200°C, it was shown that for PU/PVDF blend, with the decrease of temperature and the increase in PVDF content, the non-Newtonian index decreased, while the viscosity of the blend increased.

Templating Nanopores Into Poly(MethylSilsesquioxane): New Lowdielectric Coatings Suitable for MicroElectronic Applications

1998 ◽  
Vol 511 ◽  
Author(s):  
Julius F. Remenar ◽  
Craig J. Hawker ◽  
James L. Hedrick ◽  
Sung Mog Kim ◽  
Robert D. Miller ◽  
...  
Keyword(s):  
Experimental Data ◽  
Thin Films ◽  
Molecular Weight ◽  
Thermal Decomposition ◽  
Dielectric Constants ◽  
Organic Polymer ◽  
Low Molecular Weight ◽  
Polymer Templates ◽  
Cross Links ◽  
Poly Caprolactone

ABSTRACTThin films of nanoporous poly(methylsilsesquioxane) have been prepared from organic/inorganic polymer hybrids. Low molecular weight 6-arm star poly(caprolactone)s are incorporated into partially pre-condensed methylsilsesquioxane resin. Upon heating, the glass resin cross-links around the organic polymer templates. Thermal decomposition of the orgainc polymer produces nanoporous thin films which show tunable dielectric constants as low as 1.9 and exhibit properties suitable for use in interconnect devices. Experimental data including porosity, morphology, and dielectric constants are presented.

Synthesis of a metal-coordinated N-substituted polybenzimidazole pyridine sulfone and method for the nondestructive analysis of thermal stability

2018 ◽  
Vol 31 (2) ◽  
pp. 238-246 ◽  
Author(s):  
Peng Yang ◽  
Li Yang ◽  
Junxiao Yang ◽  
Xuan Luo ◽  
Guanjun Chang
Keyword(s):  
Thermal Stability ◽  
Thermal Decomposition ◽  
High Performance ◽  
Decomposition Temperature ◽  
Metal Coordination ◽  
Thermal Decomposition Temperature ◽  
Quenching Effect ◽  
Good Thermal Stability ◽  
H Nmr ◽  
Performance Functional

N-substituted metal-coordinated cross-linking polybenzimidazole pyridine sulfone, as novel class of high-performance functional polymers, has been obtained by the coordination of N-substituted polybenzimidazole pyridine sulfone (Py-N-PBIS) ligand with varying content of metallic ion (Co2+, Ni2+, Zn2+). The structures of the polymers are characterized by means of fourier transform infrared spectroscopy (FT-IR) and 1H nuclear magnetic resonance (1H NMR) spectroscopy, the results show good agreement with the proposed structures. Thermogravimetric analysis measurements exhibit that the metal coordination polymers possess good thermal stability with high thermal decomposition temperature (thermally stable up to 405–510°C). More importantly, the thermal decomposition temperature of Py-N-PBIS-(Co2+, Ni2+, Zn2+) can be nondestructively detected by taking advantage of the fluorescence quenching effect of metal coordination to 2,6-Bis(2-benzimidazolyl)pyridine structure.

Improved Wear Resistance of UHMWPE Fibers by Modified Nano-Graphite

2019 ◽  
Vol 960 ◽  
pp. 148-154
Author(s):  
Hong Qiu Wang ◽  
Jia You Quan ◽  
Jun Rong Yu ◽  
Yan Wang ◽  
Jing Zhu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Thermal Decomposition ◽  
Tensile Strength ◽  
Wear Resistance ◽  
Thermogravimetric Analysis ◽  
Decomposition Temperature ◽  
Thermal Decomposition Temperature ◽  
Uhmwpe Fiber ◽  
Uhmwpe Fibers ◽  
Ultra High Molecular Weight

Single ultra-high molecular weight polyethylene (UHMWPE) fiber was modified by modified nano-graphite (NG) in wear resistance. Wear resistance, tensile strength, thermogravimetric analysis (TGA) were used to characterize the effect of modified NG on the properties of UHMWPE fiber. The results showed that with the increasing content of modified NG, the wear resistance of UHMWPE fiber was enhanced and its tensile strength was decreased. Considering the tensile strength and wear resistance of fiber, the optimum content of modified NG in UHMWPE fiber was around 0.58%. At this content, the wear resistance and thermal decomposition temperature of UHMWPE fiber were increased 1.88 times and 50°C respectively than pure UHMWPE fiber.

Synthesis and Properties of Polyamide-Imide Based on 2, 2-Bis[4-(4-Aminophenoxy)Phenyl]Hexafluoropropane and 2, 2-Bis[4-(4-Aminophenoxy)Phenyl]Propane

1998 ◽  
Vol 10 (1) ◽  
pp. 45-50 ◽  
Author(s):  
Yuvraj Singh Negi ◽  
Yoshi-Ichi Suzuki ◽  
Ichiro Kawamura ◽  
Masa-Aki Kakimoto ◽  
Yoshio Imai
Keyword(s):  
Molecular Weight ◽  
Thermal Decomposition ◽  
Main Chain ◽  
Aromatic Polyamide ◽  
Decomposition Temperature ◽  
High Yield ◽  
Absorption Analysis ◽  
Thermal Decomposition Temperature ◽  
Glass Transition Temperatures ◽  
Transparent Films

Aromatic polyamide-imides having hexafluoroisopropylidene and isopropylidene groups in the main chain of the polymer were prepared by reacting 4-chloroformylphthalic anhydride (CPA) and fluorine or non-fluorine containing diamines using low-temperature polycondensation. Polyamide-imides were obtained with high molecular weight and high yield. Thermal decomposition temperature and glass transition temperatures of polymers were above 460 °C and 275 °C respectively. Fluorine and non-fluorine containing polyamide-imides were cast into transparent films which were characterized by mechanical and water absorption analysis.

Preparation of Lignosulfonate-Chitosan Polyelectrolyte Complex

2011 ◽  
Vol 197-198 ◽  
pp. 1249-1252 ◽  
Author(s):  
Chun Hai Wang ◽  
Gui Zhen Fang ◽  
Qing Ai ◽  
Yin Feng Zhao
Keyword(s):  
Thermal Stability ◽  
Thermal Decomposition ◽  
Polyelectrolyte Complex ◽  
Raw Materials ◽  
Decomposition Temperature ◽  
Thermal Decomposition Temperature ◽  
Amino Groups ◽  
Sodium Lignosulfonate ◽  
Electrostatic Adsorption ◽  
Thermal Stability Of

Sodium lignosulfonate -chitosan (SLS-CS) polyelectrolyte complex was prepared by alkaline lignin and chitosan as raw materials. The structure and thermal stability of SLS-CS polyelectrolyte were characterized by FTIR, XRD, DSC. The results indicated that NH3+was formed by the protonated amino groups of chitosan and then came into SLS-CS polyelectrolyte complex with -SO3Na of sodium lignosulfonate through electrostatic adsorption. Compared with the sodium lignosulfonate and chitosan, the thermal decomposition temperature of SLS-CS raised and thus improved the thermal stability; the amorphous peak tends to decrease; SLS-CS polymer arrangement appeared more ordering, and the molecular interaction were enhanced.

scholarly journals METAL COMPLEX TETRAIZOINDOLES AS SENSOR MATERIALS

2002 ◽  
Vol 10 (11) ◽  
pp. 79-87
Author(s):  
Cornel Tarabasanu Mihaila ◽  
Lavinia G. Hinescu ◽  
Cristian Boscornea ◽  
Carmen Moldovan ◽  
Mihai E. Hinescu
Keyword(s):  
Thin Films ◽  
Thermal Stability ◽  
Molecular Weight ◽  
Metal Complex ◽  
Electrical Response ◽  
Average Molecular Weight ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Oxide Semiconductor ◽  
Synthesis Methods

The paper presents the synthetic routes for obtaining some organic semiconductors and their characterization in order to use in thin film deposition for gas sensing devices. An original technique was used to control the molecular weight of polymeric phthalocyanine. We have fabricated devices consisting of evaporated thin films of copper, nickel, and iron phthalocyanines onto interdigital electrodes and estimated the electrical conductivity by in-situ measurements. The films were evaporated onto substrates (gold or aluminum) which were entirely integrated in the standard CMOS (capacitor metal oxide semiconductor) technology. The objectives of this work were to improve the synthesis methods of organic metal-complex tetraizoindoles and their polymers and to evaluate their electrical response and thermal stability as evaporated thin films. We have also investigated the variation of polymers conductivity and sublimation yield with the average molecular weight. We found that for polymeric phthalocyanines, the thermal stability was higher than for Pcs monomers. The stability of polymers increased with the average molecular weight.

Preparation of Magnesium Carbonate Whisker by Using Magnesite Tailings

2010 ◽  
Vol 654-656 ◽  
pp. 2022-2024
Author(s):  
Nan Wang ◽  
Yue Yuan Li ◽  
Hong Wei Ni
Keyword(s):  
Thermal Decomposition ◽  
Aspect Ratio ◽  
Magnesium Carbonate ◽  
Decomposition Temperature ◽  
Magnesium Salt ◽  
Thermal Decomposition Temperature ◽  
Stirring Intensity

Magnesium carbonate whisker was prepared by thermal decomposition of Mg(HCO3)2 solution that was prepared through hydration and carbonation of light burnt magnesia derived from magnesite tailings. The effects of thermal decomposition conditions on the morphology of magnesium carbonate crystal were investigated. Magnesium carbonate whiskers were successfully prepared when a kind of soluble magnesium salt was added, and magnesium carbonate whiskers with the length of 20 to 60μm and aspect ratio of 10~20 were obtained under the condition of 50 °C thermal decomposition temperature and 200 rpm stirring intensity.

Measurement of Thermal Decomposition Temperature and Rate of Sodium Hydride

2020 ◽  
Author(s):  
Munemichi Kawaguchi
Keyword(s):  
Thermal Decomposition ◽  
Mass Loss ◽  
Heating Temperature ◽  
Fission Products ◽  
Sodium Hydride ◽  
Decomposition Temperature ◽  
Cold Trap ◽  
Thermal Decomposition Temperature ◽  
Heating Rates ◽  
Fundamental Research

Abstract In decommissioning sodium-cooled fast reactors, the operators can be exposed to radiation during dismantling of cold trap equipment (C/T). The C/T is higher dose equipment because the C/T trapped tritium of fission products during the operation to purify the sodium coolant. In this study, thermal decomposition temperature and rate of sodium hydride (NaH) were measured as a fundamental research for development of “thermolysis” process prior to the dismantling. We measured the thermal decomposition temperature and rate using NaH powder (95.3%, Sigma-Aldrich) in alumina pan with ThermoGravimetry-Differential Thermal Analysis (TG-DTA) instrument (STA2500 Regulus, NETZSCH Japan). The heating rates of TG-DTA were set to β = 2.0, 5.0, 10.0 and 20.0 K/min. The DTA showed endothermic reaction and the TG showed two-steps mass-loss over 580K. This first-step mass-loss was consistent with change of chemical composition of the NaH with heating (NaH → Na+1/2H2). The thermal decomposition temperature and rate were obtained from the onset temperature of the mass-loss and the simplified Kissinger plots, respectively. Furthermore, we set to the thermal decomposition temperature of around 590K, and the mass-loss rates were measured. As a result, over 590K, the thermal decomposition occurred actively, and showed good agreement with the estimation curves obtained by the simplified Kissinger plots. The thermal decomposition rate strongly depended on the heating temperature.

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