Polyvinylidene Fibers
Properties
Polyvinylidene chloride (PVDC) fibers are synthetic fibers in which the fiber-forming substance is any long chain synthetic polymer consisting of at least 80% by weight of vinylidene chloride. Dow Chemical first sold this fiber in 1940 under the trademark Saran, which is now a commonly used name for both films and fibers made from PVDC. It is manufactured by melt spinning of vinylidene chloride copolymer which results in a transparent and very smooth fiber.
The fiber is very resilient and has excellent chemical resistance to many chemicals including acids, alkalis, bleaches, oils, and most organic solvents.1 Saran does not lose its strength when exposed to sunlight and humidity and resists fading, staining, and mildew. Fabrics made from this fiber are easy to clean. It is also inherently self-extinguishing, making the addition of flame-retardants unnecessary.
| Tensile Strength (Tenacity) | Fair |
| Abrasion Resistance | Excellent |
| Absorbency | Very Low |
| Heat Resistance | Poor |
| Wrinkle Resistance | Very Good |
| Resistance to Sunlight | Excellent |
| Elasticity | Good |
| Flame Resistance | Self-extinguishing |
| Resilience | Very Good |
COMMERCIAL Saran Fibers
The main manufacturer of Saran fibers Asahi-Kasei.
Applications
Saran fibers have very low moisture regain of less than 0.1 percent and outstanding UV light and weather resistance, which makes this fiber an excellent choice for underwater, and outdoor exposure applications. Due to its excellent stain and wear resistant, it is used for home and automobile upholstery, window shades, and other more demanding applications like sports bags, and sport shoes. Saran, however, is relative expensive and heavy and, therefore, has been replaced by olefins, acrylics, and other high-performance fibers for most of these applications. Other applications include uniforms that have to be inherently non-flammable, and filters that have to resist aggressive chemicals.
1PVDC is soluble in some solvents such as tetrahydrofuran (THF) and cyclohexanone.