The Future of Polyethylene

The widespread use of plastics film for printing paper appears to be only a remote possibility in the near future. There is, however, the prospect of the establishment of polyethylene film for use in service manuals, maps and other printed articles which are required to be resistant to water, oils and other liquids. 

The greatest challenge to polyethylene is not from other materials but arises as a consequence of its own success. The vast quantities of polyethylene used each year for packaging have resulted in an undesirable level of litter. As a result of public resistance and, in some countries, legislation, growth in the use of polyethylene for packaging may be constrained in the future. 

An example of the way in which process competition works in the manufacture of plastics is the story of acrylonitrile. The first process for the production of this plastic was based upon the reaction between hydrogen cyanide and acetylene, both hard to handle, poisonous, and explosive chemicals. The raw material costs were relatively low as compared to materials for other monomers, but the plant investment and manufacturing costs were too high. As a result, originally acrylonitrile monomer (1950s) sold for about 30 cents per pound and the future of the material looked dim as other plastics such as polyethylene became available at much lower prices due to their lower production costs. 

R.G. Klimesch, The future of the high pressure process, Lecture at the conference The 1990 s Polyethylene of the Plastic and Rubber Institute, London 1992. 

Transition metal catalysts are crucial to the production of polyethylene. Indeed, it would not be practical to produce linear versions of polyethylene without these catalysts. It is difficult to imagine a world without products made from these versatile polymers in our homes, vehicles and workplaces. Ziegler-Natta and supported chromium catalysts will continue to be the dominant catalysts for LLDPE and HOPE for the foreseeable future. However, as single-site catalyst... 

Research in dimensional stabilization over the last 50 years has achieved limited but specific goals it has yet to fulfil its broader objectives. Niche markets, sueh as the use of polyethylene glycol (PEG) in the treatment of marine and waterlogged artefacts are well established. New technologies for commercial scale treatment of timber by acetylation, and for various heat treatments, have reached the market in the last decade, and may increase in importance in future. 

Ethylene derived from ethane will remain the preferred source with lower- cost ethane in the Middle East and North America responsible for the enormous increase in the capacity of polyethylene in the future. For example, the Middle East added about 20 billion poimds of new ethane-based polyethylene capacity between 2008 and 2012 [22]. 

The polyethylene recycling effort will most likely continue to increase in the future and will have an effect on the amount of polyethylene capacity that may be needed in the future. Certainly this type of recycling program will result in the more efficient use of hydrocarbon feedstock and should be encouraged by the polyethylene industry. 

Finally, one development results from returning to a basic idea from the dawn of the lead-acid battery, wherein the functions of support for the positive active material and of the separator are combined into one component the gauntlet separator [84] consisting of a coarsely porous, flexible support structure coated with micropo-rous polyethylene material for separation. The future has to show whether this approach will be able to meet all demands. 

The list of solid adsorbents is extensive, although not exhaustive. Some polymers such as PRP-1 (281,420-422) and Hitachi Gel (126, 418, 419) are not listed because their use has not been documented either extensively in one laboratory or less extensively in many laboratories. Other polymers such as PTFE, polyethylene, and polypropylene have received little attention but are listed because the polymer functionality may well be of interest. Coated supports and one ion-exchange polymer are included for comparison purposes and are given only minor discussion in this review. Bonded phases are not polymeric, but they are included because they are porous, heavily used in clinical laboratories, and have great potential for future analytical use. 

During preceding decades, the discovery of new products such as Bakelite, nylon, rayon, celluloid, polyvinyl chloride, polyethylene, Saran , and Teflon convinced chemical corporations that such products held the key to an exciting and profitable future based on a host of amazing new "miracle" materials. Research departments around the world began the search for new materials with properties designed to meet a variety of special needs. One chemist who succeeded in this kind of project was Stephanie Kwolek. 

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