Barrier material

Description

A material, such as plastic, paper or metal, that is impermeable to gas or liquid. Modern barrier materials are usually made from lightweight transparent plastic sheets whose goal is to reach the barrier properties of a metal or glass. Metal sheets, such as Aluminum foil have good barrier properties. They are often laminated with Polyethylene and/or Nylon film to provide tear and corrosion resistance. Some plastics also work well as vapor barriers (Polyvinylidene chloride, Polyester, rigid Polyvinyl chloride, , Polychlorotrifluoroethylene, Polyvinyl fluoride) while others are best for moisture (polyvinyl chloride, Regenerated cellulose, polyethylene, Polypropylene, Polymethyl methacrylate (Hatchfield 2002). Multiple materials are laminated for optimized barrier properties. For anoxia treatments, films with low oxygen permeability are best. Some examples of films with minimal oxygen transmission are: Filmpak 1193 = 0.1 cc/m2/day ( mil thick); Aclar® =14 cc/m2/day( 4.5 mil thick) ; Marvelseal® 360 = 0.01 cc/m2/day; EVOH/nylon barrier film = 2.3 cc/m2/day (3 mil thick).

Examples of some laminate films include:

Tradenames	Composition	Thickness (micron)	Adhesion	Comments
Marvelseal 360	Aluminum foil between nylon and polyethylene films	5.2 mls	Heat-seal	Strong, waterproof, vaporproof, flexible
Aclar	P	2	P	G	H
Filmpak 1193	P	2	P	H
Lintec	Polyester	25, 238, 50, 100	PSA	Hard coat
Lintec	ETFE fluoropolymer	50	PSA	Excellent outdoor durability
Lintec	Acrylic	50	PSA	Excellent transparency; flat or curved surfaces
Lintec	Polyolefin	70		Provides UV protection
Envision by 3M	Polyolefin	2 mils	Heat (50 to 100 F)	Provides UV protection
Gallery Guard by Quality media	Polyolefin	2 mils	PSA acrylic (ultraclear); no heat is recommended.	Eliminates glare

Synonyms and Related Terms

barrier plastic; barrier film; barrier board; vapor barrier; vapour barrier; air barrier; air infiltration barrier; Marvelseal® 360; Marvelseal® 470; Aclar® [AlliedSignal]; Filmpak 1193; Film O-Rap [Bell Fibre]; ESCAL; EVOH/nylon; Sperrschichtmaterial (Deut.); matériau barrière (Fr.); barreira (Port.)

Resources and Citations

• P.Hatchfield, Pollutants in the Museum Environment, Archetype Press, London, 2002.

• J.Burke, "Vapor Barrier Films" WAAC Newsletter, Vol 14, No. 2, 199, 13-17.

• Boise Cascade Paper Group, The Paper Handbook, Boise Cascade, Portland OR, 1989

• Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996

• G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 578

• Conservation Support Systems, Catalog, 1997

• Theodore J. Reinhart, 'Glossary of Terms', Engineered Plastics, ASM International, 1988

• Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000