Parafilm® M

Flexible, thermoplastic, rolled, waterproof sheet interwoven with paper to prevent adhering.

Supplied in 0.127mm (0.005") thickness. Adheres quickly and firmly to itself, covering culture tube or flask mouths and sealing petri dish edges.

• Protect the integrity of research applications with a tight moisture-barrier that holds a strong seal and doesn’t release from glassware, despite off-gassing.
• Reduce the risk of tampered data with a covering that is odorless, colorless and semi-transparent.
• Prevents moisture and volume loss due to material composition and tight seal.
• Flexible and self-sealing material allows it to cling around irregular shapes and surfaces.
• Stretches more than 200% of original length.
• Resistant up to 48 hours against many polar substances such as saline solutions, inorganic acids and alkaline solutions.

Permeability

• Oxygen: (ASTM 1927-98) 150 cc/m² d at 23°C and 50% RH
• Carbon Dioxide: (Modulated IR Method) 1200 cc/m² d at 23°C and 0% RH
• Water Vapor: (ASTM F1249-01)
  Flat: 1 g/m² d at 38°C and 90% RH
  Creased: 1 g/m² d at 38°C and 90% RH

Effects of Common Reagents

• Potassium Permanganate
  5%: No apparent effect except permanent dark brown coloration in 18 hours
  0.1%: Same as 5% except slightly less color
• Iodine solution (0.1N)
  No effect except staining brown in 18 hours
• Ethyl Alcohol (95%)
  No apparent effect except some face whitening in 24 hours
• No apparent effect in 24 hours:
  Hydrochloric Acid conc. (12N)dil. (5n)
  Sulphuric Acid conc. (36n) dil. (5n)
  Nitric Acid conc. (16n) dil. (5n)
  Sodium Hydroxide conc. (22%)
  Ammonium Hydroxide conc. (28% NH3)
  Salt (NACL) solution (20%)
  Isopropyl Alcohol (99%)
• Not recommended for use with chlorinated, non-polar aliphatic and aromatic solvents.
• Film becomes soft and sticky at about 130°F to 150°F (68°C)