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Miscibility of Nylon 66/Santoprene Blends
Published in Gabriel O. Shonaike, George P. Simon, Polymer Blends and Alloys, 2019
Nylon 66 is a trade name for polyhexamethylene adipamide, which is one of the major polyamides manufactured by a condensation reaction between hexamethylene diamine and adipic acid (10–12). Its popularity as an engineering polymer is due to its superior balance of properties, including toughness over a wide range of temperatures, impact and abrasion resistance, and good resistance to organic and petroleum products (11). However, all polyamides are water sensitive owing to the hydrogen bonding character of the amide group. Water absorption of nylon 66 in ambient temperatures can be as high as 9%. The presence of water in the structure is one of the major disadvantages of nylon because it acts as a plasticizer, thereby reducing the tensile strength and modulus while increasing both the elongation at break and the toughness (14). It is also attacked by strong acids, oxidizing agents, and concentrated solutions of certain salts (15,16). One of the major advantages of nylon 66 is that it can retain its properties to a useful degree at high temperatures (15), e.g., it can withstand short-term exposure to temperatures exceeding 200°C. Application of heat stabilizers and other chemical modifications during processing increases long-term oxidative and hydrolytic stability (15). Nylon 66 has a melting point Tm of 265°C and a glass transition temperature Tg of around 50°C when dry. β- and γ-transitions occur at about −80°C and −140°C, respectively (16).
Monomers, Polymers, and Plastics
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Nylon 66 (polyhexamethyleneadipate) is produced by the reaction of hexamethylenediamine and adipic acid (see Chapters 9 and 10 for the production of the two monomers). This produces hexamethylene diammonium adipate salt. The product is a dilute salt solution concentrated to approximately 60% and charged with acetic acid to a reactor where water is continuously removed. The presence of a small amount of acetic acid limits the degree of polymerization to the desired level. The temperature is then increased to 270°C–300°C and the pressure to approximately 16 atm, which favors the formation of the polymer. The pressure is finally reduced to atmospheric to permit further water removal. After a total of 3 h, nylon 66 is extruded under nitrogen pressure.
Polycondensation Polymers (Step-Reaction Polymerization)
Published in Charles E. Carraher, Carraher's Polymer Chemistry, 2017
Molded nylon 66 is used for lawnmower blades, bicycle wheels, tractor hood extensions, skis for snowmobiles, skate wheels, motorcycle crank cases, bearings, and electrical connections. Fiber nylon 66 is used in clothing, fabrics, and rugs (Picture 4.5).
Numerical simulation of charge generation and saturation for polymer particles by single impact on a metal plate
Published in Particulate Science and Technology, 2023
Adel Sharifi, Seyed Hassan Hashemabadi, Goodarz Ahmadi
The impact charge against the initial charge of PTFE and Nylon 66 particles after colliding with the Al plate is depicted in Figure 6(a). The ARE values for PTFE and Nylon 66 particles are 10% and 12%, respectively. According to the numerical results compared to the experimental data, the model successfully predicted the particle-wall charge transfer at a wide range of initial particle charges. The work function difference between PTFE-Al is almost 15 times that for Nylon 66-Al, while its determined C0 value is approximately 9 times, indicating that the C0 is related to the work function difference between particle and wall. Also, as the work function difference increases, so does the determined C0 parameter. The impact charge of Nylon 66- Al, unlike PTFE- Al, is positive because the Al plate work function is more than that of Nylon 66 particle.
Three new zinc(II) complexes: design, synthesis, characterization and catalytic performance
Published in Journal of Coordination Chemistry, 2022
Gong Li, Qiao Zhang, Shuang Yang, Mengdi Zhu, Yuejiao Fu, Ziheng Liu, Na Xing, Lei Shi
Selective oxidation of cyclohexane (Cy) to cyclohexanone (K, CyO) and cyclohexanol (A, CyOH), generally known as KA-oil, plays a significant role in the chemical industry since KA-oil is an important intermediate material to produce Nylon-6 and Nylon-66 polymers [1–5]. It is vital to find suitable selective oxidation catalysts to improve the yield of KA-oil. In the past decades, research on metal catalysts with high catalytic activity for Cy oxidation has mainly concentrated on precious metal materials for their high efficiency and stability [6–9]. However, the expensive price and toxicity limit the application and development of precious metals. Therefore, non-noble transition elements with low-cost and high catalytic activity have been committed to exploration [10–12]. Among them, zinc compounds have been widely studied for their excellent activity on C-H oxidation [13–18].
Design of a novel midstream fluid waste sample collection device for patients
Published in Journal of Medical Engineering & Technology, 2021
Christopher Forrester, Aziza Mahomed
The final design for the holder was that of a cantilever clip which would sit over the rim of the toilet, with the main body of the design slotting into the side and held by means of a simple interference fit. A rib was added across the section which holds the main body firmly in place and prevents excitation of the system. A toilet was measured as having a rim thickness of 40 mm, and initial slope of 10 degrees, and the cantilever clip was designed around this, though further studies could be performed if required to verify universal compatibility across a range of models. Using SOLIDWORKS (Dassault Systèmes SolidWorks Corporation, Waltham, MA 02451), and a measured toilet seat radius from the hinge to the inner edge of the seat of 360 mm, the clip/body assembly was verified as not obstructing the movement of the seat. A draft angle was added to the outer surfaces of the holder for easy ejection. The material of choice for the holder was selected as nylon 66.