Polyethylene industrial films

Terephthalic acid and dimethyl terephthalate are used to produce polyester fibers, polyester resins, and polyester film. Terephthalic acid or dimethyl terephthalate is usually reacted with ethylene glycol to give polyethylene terephthalate) but sometimes it is combined with 1,4-butanediol to yield poly (butylene terephthalale). Polyester fibers are used in the textile industry. Films find applications as magnetic tapes, electrical insulation, photographic film, packaging, and polyester bottles. 

Lamination by photografting has been employed in obtaining barrier materials. For instance, acrylic acid graft polymerized between two low-density polyethylene (LDPE) films decreases the penetration of oxygen dramatically. Poly(vinyl alcohol) (PVA) interior films photolaminated by acrylic acid polymerization to LDPE films serve as a barrier material for oxygen and water. Such laminates have potential use in packaging industry [137]. 

The surface primer was prepared as a 40% methanol solution of a vinyl benzyl amine functional silane (Dow Corning Corporation Z-6032) by slowly adding methanol and then water. The mixture was allowed to stand for 24 hours to hydrolyze the silane and allow the low molecular weight oligomers to form. Samples of low density polyethylene (LDPE) film. 005" thick, supplied by U. S. Industrial Chemical Company (Resin NA140-00 containing no antioxidants) were prepared for use as the oleflnlc substrate. 

The aluminum-polyethylene composite film was manufactured by the industrial equipment at Nanking Communication Cable Company, People s Republic of China. The aluminum foil was passed through the tank containing 10%... 

Industrial films of such chemical composition as polyethylene, polypropylene and polyester are manufactured for a wide range of applications. Accordingly, the morphology of these materials is studied to determine structure-property relations, to understand how to improve properties and also to control the quality of commercial products. Although model studies provide considerable detail relating to the structure, both before and after deformation of such films, model... 

In the examination of potential applications for these unique materials that possess a wide variety of properties depending on copolymer composition, the Dow group examined finished articles formed by injection and blow molding, blown and cast film and melt extrusion. Potential applications for these new materials would be as substitute materials for flexible PVC, styrenic block copolymers, ethylene/vinyl acetate copolymers and ethylene/propylene-based elastomers. These new ethylene/styrene copolymers once again demonstrate that new catalyst technology creates new markets and applications for the polyethylene industry by competing with materials outside of the polyethylene product mix. 

The introduction of polyethylene for consumer applications began immediately at the conclusion of World War II, when polyethylene capacity increases at ICI, DuPont and Union Carbide accelerated the rapid growth of the polyethylene industry. Fabrication methods were developed for applications in film, pipe, injection molding and blow molding. Polyethylene consumption in 1953 in the United States was about 144 million pounds, which was a 24-fold increase over the 1945 production. For the year 1953, the applications for polyethylene by the fabrication method are summarized in Table 6.1. 

In the 1950s, polyethylene film for food packaging became an enormously important growth area for the polyethylene industry. Polyethylene was able to replace other packaging materials such as paper and cellophane and open up new markets for food packaging such as fresh produce. There were several product attributes of polyethylene over other packaging materials that accormted for this rapid growth. 

HDPE accounts for about 42 percent of the domestic polyethylene market. It is harder, more rigid, and less waxy in appearance than HP-LDPE. Its higher density gives it better gas barrier properties. Because it softens above 100°C, containers made with HDPE can be sterilized, but those made with LDPE cannot. It is extruded into pipe, trash bags, food packaging, multiwalled sack liners, wire and cable coverings, and thick industrial film. A large application is for blow-molded containers and housewares. 

At the end of the 1970s considerable interest developed in what became known as linear low density polyethylenes (LLDPE) which are intermediate in properties and structure to the high pressure and low pressure materials. While strictly speaking these are copolymers it is most convenient to consider them alongside the homopolymers. The LLDPE materials were rapidly accepted by industry particularly in the manufacture of film. The very low density polyethylenes (VLDPE) introduced by Union Carbide in 1985 were closely related. 

Self-curing butyl adhesives can be used for laminating polyethylene film and for flocking adhesives. One of the most important applications is the use of BR as curing, solvent-dispersed and contact-grade for roof manufacturing on industrial buildings. 

Polyethylene terephthalate) (PET) has become a major synthetic polymer during the past forty years. Significant commercial markets [1] have been developed for its application in textile and industrial fibers, films, and foamed articles, containers for carbonated beverages, water and other liquids, and thermoformed applications (e.g. dual ovenable containers). 

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