March 22nd, 2019
High-performance barrier films are engineered to elevate the fundamental chemical properties of components in demanding application areas. This requires careful consideration of the thermomechanical conditions and the unique chemistry of application environments, alongside a comprehensive understanding of the polymers used to generate specialty films. Provided the correct grade barrier film is employed, numerous thermal, chemical, mechanical, and dielectric benefits can be imparted to components in an array of application areas.
Saint-Gobain Specialty Films provide a proprietary range of CHEMFILM® Flex Barriers that are engineered from the highest quality virgin polytetrafluoroethylene (PTFE) resins to tight tolerances. This enables tight control to facilitate the generation of both single- and multi-layer barrier films for industries as varied as aerospace, industrial, electronics, and life sciences.
This blog post will outline the benefits that barrier films such as CHEMFILM® Flex Barriers provide in more detail.
The flex fatigue life of a material determines its ability to withstand repeated cycles of stress without succumbing to failure. Testing is conducted by continuously bending and flexing the film until it breaks; a property that is primarily determined by environmental conditions and the mechanical characteristics of the barrier film.
CHEMFILM® Flex Barriers boast a tensile strength range from 3000 – 4000 psi, representing an exceptional resistance to elongation fatigue. This is reinforced by the relatively low elongation at break, or fracture strain, of at least 280 % (min. values) and a tensile modulus of 80,000 psi. These mechanical properties can improve the flex lives and therefore life time of various components, limiting costly maintenance and machine downtime due to mechanical stress.
Near-Universal Chemical Resistance
Virgin PTFE is chemically inert in the presence of almost all chemicals, with the notable exception of alkali metals. Barrier films are subsequently suited for application to components that regularly encounter corrosive media. This ground-breaking chemical performance imparts outstanding corrosion resistant properties to components due to the low permeability of the material and its extremely low moisture absorption characteristics (>0.01%).
High Thermal Performance
Temperature is another critical factor that can determine the longevity of barrier films in myriad applications. CHEMFILM® products manufactured from virgin PTFE exhibit typical continuous use temperatures of 260°C (500°F); enabling little to no loss of mechanical function at elevated temperatures for as many as 20,000 service hours. Although it is not advisable to subject polymer barrier films to higher peak temperatures for extended periods, CHEMFILM® Flex Barriers are certified with a typical melt temperature of 327°C (620°F), providing peace of mind for extreme operating conditions.
Barrier Films from Saint-Gobain Specialty Films
Saint-Gobain Specialty Films specializes in the development of high-performance polymer films for an array of applications. We offer CHEMFILM® Flex Barriers in two primary subfamilies: the FR and LP versions. FR Barrier Films offer a lifetime increase of up to 70% compared to alternative premium PTFE films, while LP versions provide a higher chemical barrier with up to 30 % reduced permeability properties.