scholarly journals Curing Behaviors of Alkynyl-Terminated Copolyether with Glycidyl Azide Polymer in Energetic Plasticizers

Polymers ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1199 ◽  
Author(s):  
Jinghui Hu ◽  
Yina Liu ◽  
Kun Cong ◽  
Jiyu He ◽  
Rongjie Yang
Keyword(s):  
Diffusion Coefficient ◽  
Polyethylene Oxide ◽  
Photoelectron Spectroscopy ◽  
Gel Permeation Chromatography ◽  
Resonance Spectroscopy ◽  
Curing Process ◽  
Glycidyl Azide Polymer ◽  
The Difference ◽  
Energetic Plasticizers ◽  
Glycidyl Azide

Alkynyl-terminated polyethylene oxide−tetrahydrofuran (ATPET) and glycidyl azide polymer (GAP) could be linked through click-chemistry between the alkynyl and azide, and the product may serve a binder for solid propellants. The effects of the energetic plasticizers A3 [1:1 mixture of bis-(2,2-dinitropropy) acetal (BDNPA) and bis-(2,2-dinitropropyl) formal(BDNPN)] and Bu-NENA [N-butyl-N-(2nitroxyethyl) nitramine] on the curing reaction between ATPET and GAP have been studied. A diffusion-ordered nuclear magnetic resonance spectroscopy (DOSY-NMR) approach has been used to monitor the change in the diffusion coefficient of cross-linked polytriazole polyethylene oxide−tetrahydrofuran (PTPET). The change in the diffusion coefficient of PTPET with A3 plasticizer is significantly higher than that of PTPET with Bu-NENA. Viscosity analysis further highlighted the difference between A3 and Bu-NENA in the curing process—the curing curve of PTPET (A3) with time can be divided into two stages, with an inflection point being observed on the fourth day. For PTPET (Bu-NENA), in contrast, only one stage is seen. The above methods, together with gel permeation chromatography (GPC) analysis, revealed distinct effects of A3 and Bu-NENA on the curing process of PTPET. X-ray Photoelectron Spectroscopy (XPS) analysis showed that Bu-NENA has little effect on the valence oxidation of copper in the catalyst. Thermogravimetric (TG) analysis indicated that Bu-NENA helps to improve the thermal stability of the catalyst. After analysis of several possible factors by means of XPS, modeling with Material Studio and TG, the formation of molecular cages between Bu-NENA and copper is considered to be the reason for the above differences. In this article, GAP (Mn = 4000 g/mol) was used to replace GAP (Mn = 427 g/mol) to successfully synthesize the PTPET elastomer with Bu-NENA plasticizer. Mechanical data measured for the PTPET (Bu-NENA) sample included ε = 34.26 ± 2.98%, and σ = 0.198 ± 0.015 MPa.

scholarly journals The Effect of Glycidyl Azide Polymer Grafted Tetrafunctional Isocyanate on Polytriazole Polyethylene Oxide-Tetrahydrofuran Elastomer and its Propellant Properties

Polymers ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 278 ◽  
Author(s):  
Jinghui Hu ◽  
Weiqiang Tang ◽  
Yonghui Li ◽  
Jiyu He ◽  
Xiaoyan Guo ◽  
...  
Keyword(s):  
Mechanical Strength ◽  
Polyethylene Oxide ◽  
Mechanical Test ◽  
Glycidyl Azide Polymer ◽  
Interface Interaction ◽  
Ft Ir ◽  
Glycidyl Azide

A new energetic curing reagent, Glycidyl azide polymer grafted tetrafunctional isocyanate (N100-g-GAP) was synthesized and characterized by FT-IR and GPC approaches. Polytriazole polyethylene oxide-tetrahydrofuran (PTPET) elastomer was prepared by N100-g-GAP and alkynyl terminated polyethylene oxide-tetrahydrofuran (ATPET). The resulting PTPET elastomer was fully characterized by TGA, DMA, FTIR and mechanical test. The above analysis indicates that PTPET elastomers using N100-g-GAP as curing reagent have the potential for use in propellants. The overall formulation test of the composite propellants shows that this curing system can effectively enhance mechanical strength and bring a significant improvement in the interface interaction between the RDX & AP particles and binder matrix.

scholarly journals Fluoropolymer/Glycidyl Azide Polymer (GAP) Block Copolyurethane as New Energetic Binders: Synthesis, Mechanical Properties, and Thermal Performance

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2706
Author(s):  
Minghui Xu ◽  
Xianming Lu ◽  
Ning Liu ◽  
Qian Zhang ◽  
Hongchang Mo ◽  
...  
Keyword(s):  
Thermal Performance ◽  
Mechanical Performance ◽  
Gel Permeation Chromatography ◽  
Raw Material ◽  
Toluene Diisocyanate ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Glycidyl Azide Polymer ◽  
The Impact ◽  
Glycidyl Azide

In order to enhance the application performance of glycidyl azide polymer (GAP) in solid propellant, an energetic copolyurethane binder, (poly[3,3-bis(2,2,2-trifluoro-ethoxymethyl)oxetane] glycol-block-glycidylazide polymer (PBFMO-b-GAP) was synthesized using poly[3,3-bis(2,2,2-trifluoro-ethoxymethyl)oxetane] glycol (PBFMO), which was prepared from cationic polymerization with GAP as the raw material and toluene diisocyanate (TDI) as the coupling agent via a prepolymer process. The molecular structure of copolyurethanes was confirmed by attenuated total reflectance-Fourier transform-infrared spectroscopy (ATR–FTIR), nuclear magnetic resonance spectrometry (NMR), and gel permeation chromatography (GPC). The impact sensitivity, mechanical performance, and thermal behavior of PBFMO-b-GAP were studied by drop weight test, X-ray photoelectron spectroscopic (XPS), tensile test, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA), respectively. The results demonstrated that the introduction of fluoropolymers could evidently reduce the sensitivity of GAP-based polyurethane and enhance its mechanical behavior (the tensile strength up to 5.75 MPa with a breaking elongation of 1660%). Besides, PBFMO-b-GAP exhibited excellent resistance to thermal decomposition up to 200 °C and good compatibility with Al and cyclotetramethylene tetranitramine (HMX). The thermal performance of the PBFMO-b-GAP/Al complex was investigated by a cook-off test, and the results indicated that the complex has specific reaction energy. Therefore, PBFMO-b-GAP may serve as a promising energetic binder for future propellant formulations.

scholarly journals Application of 1H DOSY NMR in Measurement of Polystyrene Molecular Weights

2020 ◽  
Vol 36 (2) ◽  
Author(s):  
Nguyen Hoai Nam ◽  
Nguyen Huu Tho ◽  
Nguyen Minh Ngoc ◽  
Pham Quang Trung
Keyword(s):  
Molecular Weight ◽  
Diffusion Coefficient ◽  
Hydrodynamic Radius ◽  
Gel Permeation Chromatography ◽  
Resonance Spectroscopy ◽  
Solvent Interaction ◽  
Molecular Weights ◽  
External Calibration Curve ◽  
Dosy Nmr

In this work, we studied the applicability of diffusion ordered nuclear magnetic resonance spectroscopy (DOSY NMR) as an alternative method in determination of polystyrene molecular weight. DOSY NMR spectroscopy allows measuring the diffusion coefficient of molecule which directly depend on hydrodynamic radius and so on, average molar mass in weight (Mw). By using commercial polystyrene (PS) standards, an external calibration curve was established. Based on the excellent linear correlation between diffusion coefficient (logD) and molecular weight (logM), the molecular weight of polystyrene can be predicted using the following equation . The validation was done by comparing with the Mw value obtained by gel permeation chromatography within less than 5% deviation. From the diffusion coefficient, some property of polystyrene in solution, such as Flory coefficient and polymer-solvent interaction, were also studied. The Flory coefficient confirmed that chloroform is a good solvent for PS.

scholarly journals Glycidyl Azide Polymer and its Derivatives-Versatile Binders for Explosives and Pyrotechnics: Tutorial Review of Recent Progress

Molecules ◽  
2019 ◽  
Vol 24 (24) ◽  
pp. 4475 ◽  
Author(s):  
Tomasz Jarosz ◽  
Agnieszka Stolarczyk ◽  
Agata Wawrzkiewicz-Jalowiecka ◽  
Klaudia Pawlus ◽  
Karolina Miszczyszyn
Keyword(s):  
Recent Progress ◽  
Glycidyl Azide Polymer ◽  
Structural Alterations ◽  
Energetic Properties ◽  
Different Types ◽  
Curing Agents ◽  
The Difference ◽  
Glycidyl Azide

Glycidyl azide polymer (GAP), an energetic binder, is the focus of this review. We briefly introduce the key properties of this well-known polymer, the difference between energetic and non-energetic binders in propellant and explosive formulations, the fundamentals for producing GAP and its copolymers, as well as for curing GAP using different types of curing agents. We use recent works as examples to illustrate the general approaches to curing GAP and its derivatives, while indicating a number of recently investigated curing agents. Next, we demonstrate that the properties of GAP can be modified either through internal (structural) alterations or through the introduction of external (plasticizers) additives and provide a summary of recent progress in this area, tying it in with studies on the properties of such modifications of GAP. Further on, we discuss relevant works dedicated to the applications of GAP as a binder for propellants and plastic-bonded explosives. Lastly, we indicate other, emerging applications of GAP and provide a summary of its mechanical and energetic properties.

scholarly journals Influence of Combustion Modifiers on the Cure Kinetics of Glycidyl Azide Polymer Based Propellant-Evaluated through Rheo-Kinetic Approach

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 637 ◽  
Author(s):  
Liming He ◽  
Jun Zhou ◽  
Sulan Dai ◽  
Zhongliang Ma
Keyword(s):  
Measurement Method ◽  
Catalytic Effect ◽  
Cure Kinetics ◽  
Curing Process ◽  
Model Data ◽  
Glycidyl Azide Polymer ◽  
Rheological Measurement ◽  
Curing Reaction ◽  
Kinetics Of ◽  
Glycidyl Azide

To investigate the influence of combustion modifiers on the curing of glycidyl azide polymer spherical propellants (GAPSPs), the curing process of the GAPSPs was explored using an isothermal rheological measurement method. The parameters of cure kinetics were solved to further establish a kinetic model for the curing reaction of GAPSPs. The results showed that the curing process of GAPSPs under isothermal conditions conformed to the Kamal and LSK (Lu–Shim–Kim) models. The model data indicated significant agreement with the experimental data. The influence of four kinds of combustion performance modifiers on the curing process was explored and the results demonstrated that lead phthalate had a catalytic effect on the curing reaction of GAPSPs, whilst oxides of lead and copper, and copper adipate had no influence on the curing reaction.

Compatibility of energetic plasticizers with the triblock copolymer of polypropylene glycol-glycidyl azide polymer-polypropylene glycol (PPG-GAP-PPG)

2020 ◽  
Vol 40 (10) ◽  
pp. 797-805
Author(s):  
Fahimeh Ghoroghchian ◽  
Yadollah Bayat ◽  
Fatemeh Abrishami
Keyword(s):  
Mechanical Properties ◽  
Triblock Copolymer ◽  
Polypropylene Glycol ◽  
Scanning Calorimetry ◽  
Glycidyl Azide Polymer ◽  
Sem Images ◽  
Rheological Analysis ◽  
Vacuum Stability Test ◽  
Energetic Plasticizers ◽  
Glycidyl Azide

AbstractGlycidyl azide polymer (GAP) is well known as an energetic prepolymer, but its application as a binder in propellants is limited due to its relatively high glass transition temperature and relatively poor mechanical properties. Copolymerization of GAP with polypropylene glycol (PPG) has been shown to improve GAPs properties because of the good thermal and mechanical properties of PPG. In this research we synthesized triblock copolymer of PPG-GAP-PPG and the compatibilities of this copolymer were investigated with energetic plasticizers (20% w/w) n-butyl nitroxyethylnitramine (BuNENA), trimethylolethane trinitrate (TMETN), and butanetriol trinitrate (BTTN) by solubility parameter, differential scanning calorimetry (DSC), rheological analysis, scanning electron microscopy (SEM) and vacuum stability test (VST). The DSC results showed that BuNENA had better compatibility with the triblock copolymer in comparison to TMETN and BTTN. It reduced the Tg of PPG-GAP-PPG from −58 to −63 °C. The rheological analysis was in good agreement with the DSC results obtained for the compatibility of the plasticizers. In the case of the addition of 20% w/w BuNENA, the viscosity of copolymer/plasticizer decreased from 550 to 128 mPa s, indicating appropriate compatibility of plasticizer with the copolymer. SEM images showed a better distribution of BuNENA in the copolymer matrix.

DEVELOPMENT OF A DIRECT INJECTION GAS-HYBRID ROCKET SYSTEM USING GLYCIDYL AZIDE POLYMER

2019 ◽  
Vol 18 (2) ◽  
pp. 157-170
Author(s):  
Yutaka Wada ◽  
S. Hatano ◽  
Ayana Banno ◽  
Yo Kawabata ◽  
Hiroshi Hasegawa ◽  
...  
Keyword(s):  
Direct Injection ◽  
Hybrid Rocket ◽  
Glycidyl Azide Polymer ◽  
Rocket System ◽  
Glycidyl Azide

scholarly journals Effect of DMPA and Molecular Weight of Polyethylene Glycol on Water-Soluble Polyurethane

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1915 ◽  
Author(s):  
Eyob Wondu ◽  
Hyun Woo Oh ◽  
Jooheon Kim
Keyword(s):  
Molecular Weight ◽  
Contact Angle ◽  
Polyethylene Glycol ◽  
Photoelectron Spectroscopy ◽  
Water Solubility ◽  
Soft Segment ◽  
Water Soluble ◽  
Size Exclusion ◽  
Resonance Spectroscopy ◽  
Scanning Calorimetry

In this study water-soluble polyurethane (WSPU) was synthesized from isophorone diisocyanate (IPDI), and polyethylene glycol (PEG), 2-bis(hydroxymethyl) propionic acid or dimethylolpropionic acid (DMPA), butane-1,4-diol (BD), and triethylamine (TEA) using an acetone process. The water solubility was investigated by solubilizing the polymer in water and measuring the contact angle and the results indicated that water solubility and contact angle tendency were increased as the molecular weight of the soft segment decreased, the amount of emulsifier was increased, and soft segment to hard segment ratio was lower. The contact angle of samples without emulsifier was greater than 87°, while that of with emulsifier was less than 67°, indicating a shift from highly hydrophobic to hydrophilic. The WSPU was also analyzed using Fourier transform infrared spectroscopy (FT-IR) to identify the absorption of functional groups and further checked by X-ray photoelectron spectroscopy (XPS). The molecular weight of WSPU was measured using size-exclusion chromatography (SEC). The structure of the WSPU was confirmed by nuclear magnetic resonance spectroscopy (NMR). The thermal properties of WSPU were analyzed using thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC).

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