Characteristics of vinyl trifluoride

Vinyl trifluoride (PCTFE) is one of the fluoroplastics synthesised and commercialised. With its ultra-low dielectric constant and losses, as well as excellent properties such as moisture permeability, corrosion resistance, light transmission and creep resistance, it has great potential to break through development bottlenecks in high-frequency communications. In addition, PCTFE base materials already play an important role in several high-tech fields, including the chemical, medical, aerospace and electrical industries. However, in terms of fundamental research, the chemical and physical structure of PCTFE has been reported mostly in the last century, and very little in recent years.

Vinyl trifluoride has excellent properties such as heat resistance, chemical resistance, electrical insulation and high mechanical strength. It is an irreplaceable alternative to other polymers in the defence and high-tech industries. To improve the high viscosity and difficult extrusion processing of vinyl trifluoride (PCTFE), DuPont first synthesized ECTFE in 1946, in which ethylene and vinyl trifluoride alternate in a 1:1 ratio to form links, enabling ECTFE to maintain PCTFE at the same time. heat, chemical and weathering resistance, while effectively improving its thermoplastic processing properties. The strength, abrasion resistance and creep resistance of ECTFE materials are superior to polytetrafluoroethylene (PTFE) and perfluorovinyl propylene (FEP), and the chemical resistance is comparable to that of perfluoropolymers. ECTFE is insoluble in alkalis or amines and is resistant to chlorine and chlorine derivatives at high temperatures. It can be used safely at temperatures ranging from low to 149°C and still retains good mechanical strength and impact resistance. Suitable for making wire and cable. ECTFE is also used in the production of wire and cable, filter housings, fibre optic sleeves, reinforced plastic pipe linings, high performance microporous films, etc. Scholars have successively studied ECTFE microporous membranes, but there are fewer reports on fibres. ECTFE fibres were developed by means of melt extraction film protofibrillation. The basic properties and main applications of ECTFE monofibres are briefly described, but little research has been reported on the structure and properties of ECTFE fibres. In this work, ECTFE was used as a fibre-forming polymer and ECTFE fibres were prepared by melt spinning techniques.

Copolymers of ethylene and trifluorochloroethylene are known to be chemically and mechanically resistant, particularly to oxidising agents and strong alkaline solutions. These properties make the use of ethylene/chloroethylene trifluoride polymers in membrane applications very beneficial, especially in the field of wastewater treatment where membrane cleaning requires the use of strong oxidising and corrosive agents. The ethylene/trifluorochloroethylene polymer is separated from the diffusion-induced phase in solution and comprises the steps of: providing a solution comprising the ethylene/trifluorochloroethylene polymer in a solvent at a melt temperature not exceeding 200°C; casting the polymer solution into a film; and immersing the film in a non-solvent bath to precipitate the polymer. Also disclosed are films made from a composition comprising an ethylene/trifluorochloroethylene polymer with a melt temperature of up to 200°C and at least one polymer.