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BoPET film has been used in the production of banjos and drumheads since 1958 due to its durability and acoustical properties when stretched over the bearing edge of the drum. They are made in single- and double-ply versions, with each ply being 2–10 mils (0.051–0.254 mm) in thickness, with a transparent or opaque surface, originally used ...
Two methods are widely used for producing BOPP films, namely, a bi-directional stenter process or a double-bubble blown film extrusion process. [39] Biaxial orientation increases strength and clarity. [40] BOPP is widely used as a packaging material for packaging products such as snack foods, fresh produce and confectionery.
Plastic films are usually thermoplastics and are formed by melting for forming the film. [2] Cast – Plastics extrusion can cast film which is cooled or quenched then wound up on a roll. Extruded film can be stretched, thinned, or oriented in one or two directions. Blown or tubular process forces air into an extruded ring to expand the film ...
Polyvinylidene chloride is applied as a water-based coating to films made of other plastics, such as biaxially-oriented polypropylene (BOPP) and polyethylene terephthalate (PET). This coating increases the barrier properties of the film, reducing the permeability of the film to oxygen and flavours and thus extending the shelf life of the food ...
The family of shrink films has broadened over the years with many multi-layer constructions being sold today. Shrink film attributes include shrink, sealability, optics, toughness, and slip. With regard to shrink properties, there are onset temperature, free shrink, shrink force, shrink temperature range, memory, and overall package appearance.
The polluting effects of carbon disulfide and other by-products of the process used to make viscose may have also contributed [citation needed] to its falling behind lower cost petrochemical-based films such as biaxially-oriented polyethylene terephthalate (BoPET) and biaxially oriented polypropylene (BOPP) in the 1980s and 1990s. However, as ...
Banknotes of the Australian dollar in a wallet. In 1988, Australia was the first country to introduce polymer banknotes for circulation. Polymer banknotes are banknotes made from a synthetic polymer such as biaxially oriented polypropylene (BOPP).
Most polyolefin are made by treating the monomer with metal-containing catalysts. The reaction is highly exothermic. Traditionally, Ziegler-Natta catalysts are used. Named after the Nobelists Karl Ziegler and Giulio Natta, these catalysts are prepared by treating titanium chlorides with organoaluminium compounds, such as triethylaluminium.