 thumb|tyvek house wrap tyvek  is a brand of flashspun high-density polyethylene fibers, a synthetic material; the name is a registered trademark of dupont. the material is very strong; it is difficult to tear but can easily be cut with scissors or a knife. water vapor can pass through tyvek, but not liquid water, the material lending itself to a variety of applications. ==history== tyvek is a nonwoven product consisting of spunbond olefin fiber. it was first discovered in 1955 by dupont researcher jim white who saw polyethylene fluff coming out of a pipe in a dupont experimental lab.tyvek history&nbsp;&mdash; dupont.com it was trademarked in 1965 and was first introduced for commercial purposes in april 1967.dupont tyvek marks 40 years of energy efficiency and protection june 19, 2007 dupont.com according to dupont's website, the fibers are 0.5â10 &micro;m (compared to 75&nbsp;Âµm for a human hair). the nondirectional fibers (plexifilaments) are first spun and then bonded together by heat and pressure, without binders.product handbook for dupont tyvek tyvek is manufactured at the spruance plant in richmond, virginia, and in contern, luxembourg. ==properties== thumb|200px|tyvek usps express mail envelope among tyvek's properties are: *light weight *class a flammability rating. *chemical resistance *dimensional stability *opacity *neutral ph *tear resistance ==adhesion and bonding== because it is essentially a form of plastic, some adhesives will not bond well with tyvek. however, dupont recommends starch, dextrin, casein, and animal-based adhesives over most synthetic-based adhesives, emphasizing the effectiveness of water-based and quick-drying glues as the best for bonding tyvek both to itself and to a variety of substrates. dupont also claims that the following adhesives are highly effective: *water-based synthetic lattices *ethylene/vinyl acetate *acrylic pressure-sensitive tape *solvent-based single-component polyurethane *hot glue h
1955_introductions Brand_name_materials DuPont_products Fukushima_Daiichi_nuclear_disaster Moisture_protection Nonwoven_fabrics Plastic_brands Polyolefins Synthetic_paper Technical_fabrics