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Introduction to lightweight materials
Published in S. Thirumalai Kumaran, Tae Jo Ko, S. Suresh Kumar, Temel Varol, Materials for Lightweight Constructions, 2023
Vigneshwaran Shanmugam, Rhoda Afriyie Mensah, N. B. Karthik Babu, C. Pradeep Raja, J. Ronald Aseer, A. Pugazhenthi, D. Satish Kumar, Oisik Das
Another most important material is the Polyether Ether Ketone (PEEK) that accomplishes the long-term demand of an ideal multipurpose material for biomedical applications. At present, PEEK is valued among the most important engineering polymers, all due to its outstanding properties such as high mechanical strength, better thermal stability, higher chemical resistance, good wear resistance, and anti-corrosive nature. PEEK also possesses the most desirable characteristic as the material for the future: its resistance to degradation. These properties are extremely desirable for applications in the biomedical industry. As far as the biomedical field is considered, PEEK has been progressively used as a biomaterial for orthopedic implants and prostheses since 1987 [43, 44]. PEEK is safe and does not encourage any mutagenic or cytotoxic activity as discovered from Vitro biocompatibility tests. PEEK does not produce any harmful reaction or release any harmful constituents to the human tissues, thus making it a bioinert material.
Viscoelastic Functions: Effect of Various Parameters
Published in B. R. Gupta, Rheology Applied in Polymer Processing, 2023
Armsgan[53] has reported on the effects of crystallization on mechanical properties of carbon fiber reinforced poly (ether-ether ketone) (C-PEEK) composites. PEEK is a new generation engineering polymer having good high temperature properties. It is semi-crystalline thermoplastic polymer. For this polymer it is possible with heat treatment to get trans-crystalline interphase, which is very important for material performance. The size of the spherulites are controlled by controlling the heat treatment during the manufacturing of composites [54, 55, 56], and by the microstructure of the fibre, which determines the ability to develop a transcrystalline layer[57]. There are several indications that slow-cooled or annealed materials, which have a fully developed crystalline structure, exhibit better mechanical properties [58]. Likewise the presence of transcrystallinity also Viscoelastic Functions: Effect of Various Parameters has been shown to influence the mechanical performance through its effect on fibre/matrix and on the stress transfer mechanism[59, 60].
Introduction to Thermoplastic Composites
Published in R. Alagirusamy, Flexible Towpregs and Their Thermoplastic Composites, 2022
PEEK (poly ether ether ketone) is the foremost member of the polyether ketone family. PEEK is an aromatic, semi-crystalline, thermoplastic polymer. It is commercialized for industrial purposes such as aircraft, turbine blades, piston parts, cable insulation, etc. Chemically, PEEK has a polymer repeat unit of one ketone and two ether groups. This provides a linear, fully aromatic, highly stable structure containing only carbon, hydrogen and oxygen atoms. Because of this unique structure, PEEK poses excellent thermal stability, heat and chemical resistance, and very good mechanical properties. PEEK polymers are synthesized by the step-growth polymerization i.e. through dialkylation of the bisphenolate salts. The synthesis of PEEK polymer through the reaction of disodium salt of hydroquinone with 4, 4-difluorobenzophenone is shown in Figure 1.9. PEEK has a glass transition temperature of around 143°C and it melts around 343°C. PEEK can be processed using compression moulding, injection moulding or extrusion method to manufacture various composite parts.
Physico-chemical analysis of semi-crystalline PEEK in aliphatic and aromatic solvents
Published in Soft Materials, 2019
Saima Yasin, Ahmad Shakeel, Muqarrab Ahmad, Aqeel Ahmad, Tanveer Iqbal
PEEK is an excellent thermoplastic polymer widely used in aerospace and biomedical applications. In this study, the changes in morphological and thermal stability of PEEK sample, when treated with different aromatic and aliphatic solvents, were investigated. FTIR analysis confirmed that no surface reduction or morphological change in the studied polymer was caused by these solvents. Moreover, benzyl alcohol, methanol, and chloroform showed the significant impact on the thermal stability of PEEK as evident from TGA analysis. However, crystallinity of polymer was found to be unaffected by the presence of considered solvents. GC–MS analysis detected a component N-Phenylnaphthalen-1-amine (C16H13N) with molecular weight 219 g/mol as one of the decomposition products. In the premises of these findings, it can be concluded that semi-crystalline PEEK showed considerable stability under harsh chemicals and dynamic thermal environment.
Review of Heat Exchangers Enabled by Polymer and Polymer Composite Additive Manufacturing
Published in Heat Transfer Engineering, 2018
David C. Deisenroth, Ramin Moradi, Amir H. Shooshtari, Farah Singer, Avram Bar-Cohen, Michael Ohadi
There is ongoing research in high-performance polymers compatible with powder bed fusion. For example, Berretta et al. [44] quantitatively characterized polyether ether ketone (PEEK) powder for additive manufacturing via powder bed fusion. PEEK has excellent wear resistance, stiffness, chemical and solvent resistance, mechanical strength, along with a glass transition temperature of 150°C and a melting temperature of 340°C [45]. The study on PEEK by Berretta et al. [44] developed a template for other researchers to compare polymers for powder bed fusion. Berretta et al. [44] quantitatively characterized the particle size distribution and particle shape and evaluated the effects of fillers (glass, hydroxyapatite, and calcium carbonate) on the flow behavior between adjacent particles in an effort to develop a process to increase the practicality of sintering the high-temperature polymer. Since PEEK is a relatively expensive polymer, another study has evaluated the reuse of PEEK powder with powder bed fusion [46]. Polyetherketone (PEK) is relatively similar to PEEK, but with slightly higher glass and melting temperatures. Ghita et al. [47] studied the viability of PEK for powder bed fusion, and Ghita et al. [48] studied the reuse of PEK with powder bed fusion.
Tribological Behavior of PTFE Composites Filled with PEEK and Nano-Al2O3
Published in Tribology Transactions, 2018
Qi Yuan, Gong Jun, Cao Wenhan, Wang Honggang, Ren Junfang, Gao Gui
Polyetheretherketone (PEEK) is a semicrystalline polymer that is applied widely to impart components with high strength, wear resistance, creep resistance, operating temperature resistance, and low thermal conductivity. Bijwe, et al. (36) and Burris and Sawyer (37) investigated the effects of PEEK particles on the tribological properties of PTFE composites and found that PEEK particles could significantly improve the tribological performance. Onodera, et al. (38), (39) found that the PEEK contents in the polymer blend preferentially transferred to the counterpart metal surface prior to PTFE addition and prevented detachment of the transfer film. Nanoparticles have a much higher specific surface area, hardness, and modulus than polymers and can enhance the wear resistance, mechanical properties, and load-carrying capacity of the PTFE composites. In contrast, the required content of nanoparticles in composites is much lower (<10%) than that required using traditional fillers. The low additive content enables the composite to retain the intrinsic merits of the unfilled polymers, such as their low weight and friction coefficient, ductility, and good processability.