Thermoplastics PCTFE

Many challenging industrial and military applications utilize polychlorotriduoroethylene [9002-83-9] (PCTFE) where, ia addition to thermal and chemical resistance, other unique properties are requited ia a thermoplastic polymer. Such has been the destiny of the polymer siace PCTFE was initially synthesized and disclosed ia 1937 (1). The synthesis and characterization of this high molecular weight thermoplastic were researched and utilized duting the Manhattan Project (2). The unique comhination of chemical iaertness, radiation resistance, low vapor permeabiUty, electrical iasulation properties, and thermal stabiUty of this polymer filled an urgent need for a thermoplastic material for use ia the gaseous UF diffusion process for the separation of uranium isotopes (see Diffusion separation methods). 

The typical mechanical properties that qualify PCTFE as a unique engineering thermoplastic are provided ia Table 1 the cryogenic mechanical properties are recorded ia Table 2. Other unique aspects of PCTFE are resistance to cold flow due to high compressive strength, and low coefficient of thermal expansion over a wide temperature range. 

The lower molecular weight PCTFE oils, waxes, and greases are used as inert sealants and lubricants for equipment handling oxygen and other oxidative or corrosive media. Other uses include gyroscope flotation fluids and plasticizers for thermoplastics. 

An early alternative to PTFE was poly(chlorotrifluoroethylene) (PCTFE), which was invented in 1941 by W. T. Miller at Cornell University (Scheme 4.4). In contrast with PTFE, this material can be extruded at 250-300 °C. Depending on molecular mass PCTFE has applications as a thermoplastic or a lubricant. 

Film Processing Methods Through the use of conventional thermoplastic processing techniques, PCTFE can be molded as well as extruded into transparent film and sheet, " ] and laminated, heat-sealed, printed thermoformed, metallized, and sterilized... 

Polychlorotrifluoroethylene Thermoplastic polymer of chlorotrifluoroethylene. Has good transparency, barrier properties, tensile strength, and creep resistance, modest dielectric properties and solvent resistance, and poor processibibty. Processed by extrusion, injection and compression molding, and coating. Used in chemical apparatus, low-temperature seals, films, and internal lubricants. Also called PCTFE. 

PCTFE Poly(chlorotrifluoroethene) Polychlorotrifluoroethylene (INCI) Poly (monochlorotrifluoroethylene) Polytrifluorochloroethylene Poly (trifluoroethylene chloride) Poly (trifluoromonochloroethylene) Poly(trifluorovinyl chloride) Trifluorochloroethylene polymer Classification Thermoplastic polymer fluorocarbon resin... 

Poly(chlorotrifluoroethylene) (PCTFE, Kel-F fluoropolymer) is a thermoplastic semicrystalline polymer with (-CF2CCIF-) repeating units [49], Typically, PCTFE is synthesized via a free radical polymerization using bulk, suspension, or emulsion techniques [50]. Compared with PTFE (Teflon fluoropolymer), which has similar chemical properties, there is asymmetry in the CTFE monomer unit due to the presence of the chlorine atom in CFCl groups. Consequently, the NMR features of PCTFE are more complicated due to the possible monomer- and stereo-sequence variations. Since PCTFE has various distinguished properties, including thermal, chemical, and radiation resistance, low vapor permeability, and electrical insulation [51,52], it has... 

Perfluoropolymers bum, but do not continue to bum when the flame is removed. All perfluorinated fluoropolymers pass a UL 83 vertical flame test and are classified 94 V-0 according to Underwriters Laboratory (UL) in their burning test classification for polymeric materials. Limiting oxygen index (LOI) by ASTM D2863 is 95% or higher for PTFE, PFA, FEP, and PCTFE. Partially fluorinated fluoropolymers are more flame resistant than other thermoplastics but not quite as resistant as the perfluorinated fluoropolymers, as evidenced by their lower EOI values. PVDF, ETFE, and ECTFE meet UE 94 V-0. Table 13.48 lists the EOI of various fluoropolymers. 

Polychlorotrifluoroethylene, (PCTFE) is less crystalline and less inert than PTFE it can be shaped by normal thermoplastic melt processing methods. Because of its relative transparency, it finds limited use as observation windows (in sheet form), or as specialist tube material. 

Fluorocarbons a group of thermoplastic resins which are very strong, tough and stable with excellent temperature and electrical properties. Used for electrical components and as bearing materials. Group includes FEP, PTFE and PCTFE (qv). 

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