PEEK plastic, short for polyether ether ketone<\/strong>, is a semi-crystalline engineering thermoplastic that survives 260\u00b0C continuous service while resisting almost every common industrial chemical. It is the material engineers reach for when nylon melts, when PTFE creeps under load, and when aluminum corrodes. This guide explains what PEEK is, the properties and grades that matter, where it earns its 5\u00d7-cost premium, and where specifying it is overkill.<\/p>\n <\/p>\n <\/p>\n PEEK plastic is a semi-crystalline thermoplastic within the polyaryletherketone (PAEK) family which is, as the name suggests, characterized by recurring ether and ketone groups in its structure. It was synthesized in the 1970s by ICI Materials and first marketed in 1981 under the Victrex brand. This covers a small family of materials termed high-performance plastics \u2014 polymers that retain strength, dimensional stability and chemical resistance at temperatures where most thermoplastics fail.<\/p>\n Unlike regular nylon which starts to soften around 80\u00b0C and even good quality grades like PPS that top out near 220\u00b0C, PEEK keeps working at 260\u00b0C continuously and 300\u00b0C in short bursts. That single characteristic accounts for most of why PEEK ends up in jet engines, surgical and orthopedic implants, semiconductor wafer carriers, and downhole oilfield seals.<\/p>\n If your operating temperature is under 150\u00b0C and you are only seeing mild chemical handling, you are very likely to not require PEEK; POM, PA66-GF or PPS will provide comparable mechanical properties at a lower per-pound cost.<\/p>\n<\/div>\n <\/p>\n Polyether ether ketone (PEEK) is synthesized by step-growth polycondensation \u2014 a nucleophilic substitution reaction between hydroquinone and 4,4′-difluorobenzophenone in a polar aprotic solvent. This produces long chains of alternating ether (\u2014O\u2014) and ketone (\u2014CO\u2014) groups separated by para-substituted phenyl rings. Repetition of that ether-ketone structure gives PEEK most of its useful properties.<\/p>\n Two structural details matter for buyers and engineers:<\/p>\n PEEK can be processed via injection molding (mold temp 180\u2013200\u00b0C, melt temp 380\u2013400\u00b0C), extrusion into rod, sheet, or tube stock, or fused filament fabrication for additive manufacturing. The high processing temperatures explain why standard injection molding shops cannot run PEEK products without specialized hot-runner systems.<\/p>\n <\/p>\nQuick Specs \u2014 PEEK at a Glance<\/h3>\n
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\n Chemical name<\/td>\n Polyether ether ketone (PEEK), PAEK family<\/td>\n<\/tr>\n \n Continuous service temp<\/td>\n 250\u2013260\u00b0C (480\u2013500\u00b0F)<\/td>\n<\/tr>\n \n Melting point<\/td>\n 343\u00b0C (650\u00b0F)<\/td>\n<\/tr>\n \n Glass transition (Tg)<\/td>\n 143\u00b0C<\/td>\n<\/tr>\n \n Density<\/td>\n 1.32 g\/cm\u00b3<\/td>\n<\/tr>\n \n Tensile strength<\/td>\n 90\u2013100 MPa (unfilled), up to 220 MPa (carbon-filled)<\/td>\n<\/tr>\n \n Flame rating<\/td>\n UL94 V-0<\/td>\n<\/tr>\n \n Industrial cost (2026)<\/td>\n $80\u2013200\/kg unfilled, $300\u2013500\/kg medical-grade<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n What Is PEEK Plastic?<\/h2>\n
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<\/p>\nHow PEEK Is Made: Chemistry and Polymer Structure<\/h2>\n
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PEEK Material Properties: Mechanical, Thermal, Chemical, Electrical<\/h2>\n
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