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Polyhexahydrotriazines: Synthesis and Thermal Studies
Published in Didier Rouxel, Sabu Thomas, Nandakumar Kalarikkal, Sajith T. Abdulrahman, Advanced Polymeric Materials, 2022
Nitish Paul Tharakan, J. Dhanalakshmi, C. T. Vijayakumar
Cyanate ester is a thermosetting polymer that can withstand very high temperatures, as well as maintain good thermal, mechanical, and electrical properties at these temperatures [10]. These properties make cyanate ester a very attractive choice for use in many applications as well as the manufacture of composite materials.
Resins
Published in Martin W. Jawitz, Michael J. Jawitz, Materials for Rigid and Flexible Printed Wiring Boards, 2018
Martin W. Jawitz, Michael J. Jawitz
Cyanate ester resins are bisphenol derivates containing the ring-forming cyanate (–O–C≡N) functional groups (Figure 2.11). Cyanate ester is a cyclotrimer of dicyanate. The trifunctional cyanate ester cross-links to form a high-temperature polymer (Tg 235°C or higher). In their purest form, these resins are very brittle and have low peel strength. To overcome this, these resins are blended with either epoxy or a small amount of polyimide resins. This blend is called “BT,” named after its two major components: bismaleimide and triazine. By varying the ratio of either of the two components, you can handpick the desired Dk. The composition of 10% by weight bismaleimide and 90% by weight triazine results in a similar curing temperature as that of epoxy resin. In most cases, BT resins can be substituted for polyimide resins.
Second-Level Packaging Materials
Published in Mitel G. Pecht, Rakesh Agarwal, Patrick McCluskey, Terrance Dishongh, Sirus Javadpour, Rahul Mahajan, Electronic Packaging: Materials and Their Properties, 2017
Mitel G. Pecht, Rakesh Agarwal, Patrick McCluskey, Terrance Dishongh, Sirus Javadpour, Rahul Mahajan
Cyanate ester resins are formed by the cyclotrimerization reaction of aryl dicyanates (Mumby 1989a). Advantages of cyanate ester resins include their low dielectric constant and loss factor, which vary little with temperature and electromagnetic frequency compared with other thermosetting resins. Further, the physical properties of the cyanate ester resins are tailorable by the proper choice of the aryl dicyanate molecular structure. Cyanate ester resins are one of the most promising resins for high-speed applications. They are available from many manufacturers such as Dow Chemical Company and Hi-Tek Polymers, Inc.
A high-precision apparatus for dimensional characterization of highly stable materials in space applications
Published in Mechanics of Advanced Materials and Structures, 2022
Baolong Sun, Hansi Zhang, Chuang Xue, Weihui Shang
The lamination angles of the CFRP tube were (0°/+61°/0°/0°/−61°/0°)4s, where the ±61° layers were made up of T700SC prepreg, and the 0° layers were made up of M40JB prepreg. The resin matrix was medium-temperature curing cyanate ester resin, and the curing temperature was 130 °C. The theoretical CTE of the tube was 0.113 × 10−6/°C, the length of the tube was 2169 mm, the outer diameter was 80 mm, and the wall thickness was 4.8 mm (as shown in Figure 18). Due to the high requirements for quantitative control of the tubes in this program, the use of hot-melt prepreg for laying and forming achieved stable control of thickness and fiber volume content. In addition, the hand layup M40JB plies and the machine-applied pre-impregnated T700SC plies were selected as the molding process for composite tubes to control the stability of the axial thermal expansion coefficient.
Fabrication and testing of hybrid fibre reinforced composite: a comprehensive review
Published in Australian Journal of Mechanical Engineering, 2022
Kapil K. Sharma, Jitendra Kushwaha, Kapil Kumar, Harshit Singh, Yogesh Shrivastava
Metal element or alloy is used as a matrix in MMCs, e.g., Al, Mg, Pb, Ti, Cu, and their alloys. Al2O3, Si3N4, SiC, Cr2O3, WC, TiO2, etc. are used as a matrix in CMCs. In the C/Cs, reinforcements and matrix both are based on carbon (constituent’s state may be different). PMCs are very popular among the above-mentioned composites because of their light weights and are further sub-classified into three categories: thermoset, thermoplastic and elastomeric composites as shown in Figure 2. Thermoset composites can be used at elevated temperature and hence cannot be reshaped, i.e. non-recyclable. Some thermosetting polymer matrices are polyester, vinyl ester, cyanate ester, epoxy, phenolic, polyamide, etc. Thermoplastic composites cannot be used at elevated temp but can be reshaped, i.e. recyclable. Some examples of thermoplastic polymeric matrices are polyethene, polypropylene, PEEK, polyamide, etc. Elastomers, also termed as rubber material, show highly elastic mechanical properties than the other two. Vulcanisation is done on the elastomers to achieve crosslinking (Erden and Ho 2017).
Qualification of NSTX-U Inner TF Bundle Using Hi-Fidelity Models
Published in Fusion Science and Technology, 2021
Yuhu Zhai, Thomas Willard, Charles Neumeyer, Stefan Gerhardt, Peter Titus, Mark Pauley, Steve Raftopoulos, Robert Ellis, Richard Hawryluk
The TF bundle wedge-shaped turns were wrapped with glass tape and bonded together by the injection of resin using vacuum pressure impregnation (VPI) and the oven curing process. Each quadrant of nine turns is VPI processed first and joined together with ground wrap insulation via a second VPI curing process. After the bundle VPI, the OH solenoid was wound around the TF bundle and processed with another VPI and cure cycle. The TF turn insulation was subject to one VPI and three cure cycles, where turn insulation at the quadrant interfaces was subject to two VPI and three cure cycles. The bundle insulation included two half-lapped layers followed by one butt-lapped layer of S-2 woven glass of Carolina Narrow style, half-lapped layers of S-2 glass ground wrap. CTD-425 epoxy/cyanate ester hybrid was used for the VPI. An additional 1-mm-thick (0.04-in.-thick) glass wrap was used per the as-built condition for the quadrant-to-quadrant (Q-Q) insulation. Figure 3 presents insulation taping of the inner leg, the bundle quadrant assembly, the TF-OH assembly, and the bundle turn insulation.7