Silicones, also known as polysiloxanes, are polymers that include any inert, synthetic compound made up of repeating units of siloxane, which is a chain of alternating silicon atoms and oxygen atoms, frequently combined with carbon and/or hydrogen. They are typically heat-resistant and rubber-like, and are used in sealants, adhesives, lubricants, medicine, cooking utensils, and thermal and electrical insulation. Some common forms include silicone oil, silicone grease, silicone rubber, silicone resin, and silicone caulk. Silicones are of three types: 1. straight chain silicones; 2. cyclic silicones; 3. crosslinked silicones.
Sanitary hose generally involves in the systems of pharmaceutical process applications. Be it portable tank hook ups, load cell isolators, CIP jumpers or any one of a dozen other applications, sanitary hose assemblies are everywhere. They need to be steam sterilizable or autoclave without damage. There are really only two materials that meet the pharmaceutical requirements apart from meeting FDA guidelines: Pure solid silicone and smooth bore PTFE (polymer). Which one is better to use? It really depends on the application and the outcome we are trying to achieve:
Pure Solid Silicone Properties
Light in weightVery flexiblePure Silicones do not allow gas or liquid to pass throughKnown for its durability and ability to withstand chemical reactionsAbility for use in sterilized environments and also ability to withstand extreme heat & hold temperature (including cryogenic use)No “marked harmful effects on organisms in the environment have been noted for silicones. Because they are widely used, they are pervasive, biodegrade readily, as catalyzed by various clays.
PTFE Hose Properties
● Relatively heavy (comparing to silicone)● Stiffer than silicone (might be desirable or undesirable depending on the application)● The pyrolysis of PTFE is detectable at 200 °C (392 °F), and it involves several fluorocarbon gases and a sublimate.
Therefore, which is the better hose choice? Although the function of application matters while the cost differential between the two is not particularly significant. The PTFE hoses are probably preferred if you get into applications above 100 PSI. But if you need something light and flexible like that of the short load cell jumpers, silicone works great.
PS: Contact us for PTFE finished products free sample
Post time: Nov-03-2017