scholarly journals Research on the Synthesis and Performance of a New Type of Neutral Polymer Bonding Agent

2022 ◽  
Vol 2152 (1) ◽  
pp. 012004
Author(s):  
Junming Song

Abstract In order to improve the mechanical properties of nitrate ester plasticized polyether (NEPE) propellants, 3-allylic hydantoin was synthesized by hydantoin, potassium hydroxide and 3-bromopropene, and then a new type of intermediate polymer bonding agent (NPBA) was synthesized by 3-allylic hydantoin, acrylonitrile, hydroxyethyl acrylate and dimethylaminoethyl methacrylate. At the same time, two traditional neutral polymer bonding agents were synthesized for comparative study. Through the contact angle test, the bond performance prediction shows that: compared with the two traditional bond agents, the bond work between the new bond agent and oxidant (ammonium nitrate, ammonium perchlorate) is greater, indicating that the bond between the new bond agent and oxidant is stronger.

2018 ◽  
Vol 189 ◽  
pp. 08001 ◽  
Author(s):  
Ali.M.Abd elall ◽  
Guo Lin

An effective pathway was explored to design and select proper bonding agents that could effectively improve the interfacial interactions between bonding agents and solid particles, modern types of composite solid propellants focused on increasing the mechanical properties in order to withstand stresses produced due to various loading conditions, changes in environmental condition, transportation and handling. In this work, the study show that the effect of solvent in production of bonding agent has a different impact on the mechanical properties as the polar solvent in formulation S3 has a good strain values corresponding to the stress. Also the changing of the percentage of CuCl2 has a significant effect on mechanical properties as giving high value of strain with the percentage of 4.5 % and returns back the value of strain decrease with increase the percentage of CuCl2 to give the lowest values of the strain corresponding to the stress value with percentage 7.5 %.


To obtain a polymer bonded explosive (PBX) with acceptable properties it is generally considered necessary to modify the bonding of the filler explosive to the polymer matrix. This is usually achieved by the addition of a ‘bonding agent’. This paper describes an investigation of the interaction of some bonding agents with the surface of the insensitive high explosive l,3,5-triamino-2,4,6-trinitro-benzene. The mechanical properties of the surface modified explosive loaded into a matrix of isocyanate cured hydroxy-terminated polybutadiene have also been studied to elucidate the role of the bonding agent and produce a PBX with high extensibility.


Author(s):  
Romaneh Jalilian ◽  
David Mudd ◽  
Neil Torrez ◽  
Jose Rivera ◽  
Mehdi M. Yazdanpanah ◽  
...  

Abstract The sample preparation for transmission electron microscope can be done using a method known as "lift-out". This paper demonstrates a method of using a silver-gallium nanoneedle array for a quicker sharpening process of tungsten probes with better sample viewing, covering the fabrication steps and performance of needle-tipped probes for lift-out process. First, an array of high aspect ratio silver-gallium nanoneedles was fabricated and coated to improve their conductivity and strength. Then, the nanoneedles were welded to a regular tungsten probe in the focused ion beam system at the desired angle, and used as a sharp probe for lift-out. The paper demonstrates the superior mechanical properties of crystalline silver-gallium metallic nanoneedles. Finally, a weldless lift-out process is described whereby a nano-fork gripper was fabricated by attaching two nanoneedles to a tungsten probe.


2021 ◽  
Vol 2 (1) ◽  
pp. 46-62
Author(s):  
Santiago Iglesias-Baniela ◽  
Juan Vinagre-Ríos ◽  
José M. Pérez-Canosa

It is a well-known fact that the 1989 Exxon Valdez disaster caused the escort towing of laden tankers in many coastal areas of the world to become compulsory. In order to implement a new type of escort towing, specially designed to be employed in very adverse weather conditions, considerable changes in the hull form of escort tugs had to be made to improve their stability and performance. Since traditional winch and ropes technologies were only effective in calm waters, tugs had to be fitted with new devices. These improvements allowed the remodeled tugs to counterbalance the strong forces generated by the maneuvers in open waters. The aim of this paper is to perform a comprehensive literature review of the new high-performance automatic dynamic winches. Furthermore, a thorough analysis of the best available technologies regarding towline, essential to properly exploit the new winches, will be carried out. Through this review, the way in which the escort towing industry has faced this technological challenge is shown.


2021 ◽  
Vol 57 (14) ◽  
pp. 1782-1785
Author(s):  
Olumoye Ajao ◽  
Marzouk Benali ◽  
Naïma El Mehdi

New insights on the variability of solubility elucidated for diverse lignins, quantification thereby makes it possible to predict performance for solvent fractionation processes and polymers formulation.


2021 ◽  
Vol 11 (6) ◽  
pp. 2832
Author(s):  
Haibo Liu ◽  
Cunlin Xin ◽  
Lei Liu ◽  
Chunqiang Zhuang

The structural stability of high-entropy alloys (HEAs) is closely related to their mechanical properties. The precise control of the component content is a key step toward understanding their structural stability and further determining their mechanical properties. In this study, first-principle calculations were performed to investigate the effects of different contents of each component on the structural stability and mechanical properties of Co-Cr-Fe-Ni HEAs based on the supercell model. Co-Cr-Fe-Ni HEAs were constructed based on a single face-centered cubic (FCC) solid solution. Elemental components have a clear effect on their structure and performance; the Cr and Fe elements have an obvious effect on the structural stability and equilibrium lattice constant, respectively. The Ni elements have an obvious effect on stiffness. The Pugh ratios indicate that Cr and Ni addition may increase ductility, whereas Co and Fe addition may decrease it. With increasing Co and Fe contents or decreasing Cr and Ni contents, the structural stability and stiffness of Co-Cr-Fe-Ni HEAs are improved. The structural stability and mechanical properties may be related to the strength of the metallic bonding and covalent bonding inside Co-Cr-Fe-Ni HEAs, which, in turn, is determined by the change in element content. Our results provide the underlying insights needed to guide the optimization of Co-Cr-Fe-Ni HEAs with excellent mechanical properties.


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