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| Glossary |
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| A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
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Additives:
A diverse group of specialty chemicals incorporated into plastic formulations before or during processing, or to the surfaces of finished products after processing. Their primary purpose is to modify the behavior of plastics during processing or to impart useful properties to fabricated plastic articles. (Modern Plastics Encyclopedia 1995).
Advanced Recycling Technologies (ART):
Processes that yield a variety of versatile and marketable end-products that are the building blocks from which new plastics and a variety of other products can be manufactured. This is achieved by converting or recycling plastics back into the raw materials from which they were made. ART includes such processes as methanolysis, glycolysis, hydrolysis, and thermal depolymerization. These technologies augment existing mechanical systems as part of an integrated approach to plastics recycling designed to increase the volume of post-consumer plastic plastics diverted from the waste stream and expand the variety of plastics that are recycled into new and useful products. (The Evolution of Plastics Recycling Technology, APC, 1994).
The American Plastics Council (APC):
A national organization whose mission is to actively demonstrate that plastics are a preferred material and a responsible choice in a more environmentally conscious world.
Ammonolysis:
A complete depolymerization process that breaks nylon into its building blocks or monomers that can then be repolymerized to make nylon in any form and for any market. (Modern Plastics Encyclopedia 1995).
Automatic Plastics Sorting:
The separation of mixed plastics by resin type and/or color via a mechanical system. A system detects the plastic type (or types) to be segregated and removes those materials from the stream. Common systems utilize conveyors, resin/color detectors, computer analysis and tracking and air jet ejectors. For plastic packaging, the separation may be on a macro (whole container) or micro (chopped/ground particles) basis. ("Automatic Sorting for Mixed Plastics," Peter Dinger, BioCycle, March 1992; "Automatic Microsorting for Mixed Plastics," Peter Dinger, BioCycle, April 1992)
Abrasion Resistance
The ability of a polymer to withstand mechanical action, such as rubbing, scraping or erosion, which tends to remove material progressively from it's surface.
Age Resistance
The resistance to deterioration by oxygen and ozone in the air, and by heat and light. A variety of anti-oxidants are available which provide protection in differing degrees to these deteriorating factors.
Aliphatic
Any organic compound in which the main structure is a chain of carbon atoms joined to each other is classified as being aliphatic.
Alternating copolymer
A copolymer consisting of macromolecules comprising two species of monomeric units in alternating sequence.
Anionic polymerization
An ionic polymerization in which the kinetic-chain carriers are anions.
Anti-blocking and slip agents
Surface-modifying additives to reduce friction and tackiness of polyolefin films.
Antioxidants
A group of substances being able to inhibit radical reactions in the polymer and thus prevent degradation processes. Different types are available: sterically hindered phenols and phosphites as base for polyolefins, sulphur based heat stabilisers and C-radical scavengers for special applications.
Antistatic agents
Surface-modifying additives to reduce surface resistance of polyolefins, eliminating charge build-up and dust collection; an example of a widely used antistatic agent is glycerine-monostearate. Different types of antistatic agents are used in polymerization reactors to prevent the formed polymer powder from adhering to the reactor wall.
Aromatic
Aromatics are a highly reactive group of hydrocarbons with unsaturated rings of carbon atoms, producing a great variety of products. As their name implies, they have a strong odour, which is not unpleasant. |
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