Parafilm® M Sealing Films

Parafilm® M is designed for durability, chemical compatibility, and adaptability. It is non-toxic, plasticizer-free, and offers excellent resistance against acids, alkalis, and many polar organic solvents. The film’s two-way stretch allows it to mold securely around irregular shapes and surfaces. However, it is not recommended for use with chlorinated, non-polar aliphatic and aromatic solvents, as the film may soften and degrade. This versatile film is a simple, effective covering for protecting sensitive materials in a wide range of analytical and biological settings.

Features:

• Creates tight moisture-barrier that holds a strong seal and doesn’t release from glassware, despite off-gassing
• Flexible, thermoplastic film with two-way stretch (stretches over 200% of original length)
• Non-toxic and free from plasticizers, composed primarily of polyolefins and paraffin waxes
• Provides excellent sealing for test tubes, beakers, petri dishes, flasks, and cuvettes
• Good resistance against acids, alkalis, and many polar organic solvents
• Film becomes soft and sticky at about $68\text{°C}$ (130°F to 150°F)
• Available in 2 in and 4 in widths

Warning: Use is not recommended for use with chlorinated, non-polar aliphatic and aromatic solvents (e.g., acetone, diethyl ether, carbon tetrachloride). The film becomes soft and sticky at about 130°F to 150°F (68°C).

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%)

Parafilm® is a registered trademark of Bemis Company, Inc.