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- Plastic | Composition, History, Uses, Types, Facts | Britannica
Industrial fabricators of plastic products tend to think of plastics as either “ commodity” resins or “ specialty” resins (The term resin dates from the early years of the plastics industry; it originally referred to naturally occurring amorphous solids such as shellac and rosin ) Commodity resins are plastics that are produced at high volume and low cost for the most common
- Plastic pollution | Definition, Sources, Effects, Solutions, Facts . . .
Plastic pollution, harmful accumulation of synthetic plastic products in the environment Plastics are persistent large-scale pollutants, and plastic debris (such as bottles, straws, containers, and plastic wrap) and particulates have been found in many environmental niches, from Mount Everest to the bottom of the sea
- Plastic - Injection Molding, Polymers, Manufacturing | Britannica
Plastic - Injection Molding, Polymers, Manufacturing: It is usually slow and inefficient to mold thermoplastics using the compression molding techniques described above In particular, it is necessary to cool a thermoplastic part before removing it from the mold, and this requires that the mass of metal making up the mold also be cooled and then reheated for each part Injection molding is a
- Plastic pollution - Marine Debris, Microplastics, Landfill | Britannica
Plastic pollution - Marine Debris, Microplastics, Landfill: Since the ocean is downstream from nearly every terrestrial location, it is the receiving body for much of the plastic waste generated on land Several million tons of debris end up in the world’s oceans every year, and much of it is improperly discarded plastic litter The first oceanographic study to examine the amount of near
- Plastic - Recycling, Resource Recovery | Britannica
Plastic - Recycling, Resource Recovery: In many municipalities, the favoured method of disposing of solid waste is in sanitary landfills, in which layers of refuse alternate with layers of soil However, concerns over the wisdom of such land use has encouraged efforts to dispose of various materials by recycling them for re-use or to derive some positive benefits
- Plastic - Processing, Fabrication, Recycling | Britannica
Plastic - Processing, Fabrication, Recycling: The processing of raw materials into usable forms is termed fabrication or conversion An example from the plastics industry would be the conversion of plastic pellets into films or the conversion of films into food containers In this section the mixing, forming, finishing, and fibre reinforcing of plastics are described in turn
- plastic - Kids | Britannica Kids | Homework Help
A plastic is a kind of material that is made by people and can be formed into almost any shape Most plastics are strong, long-lasting, and lightweight They resist damage by water, heat, chemicals, and electricity In addition, plastics can be made in many colors
- Plastic - Foaming, Manufacturing, Properties | Britannica
Plastic - Foaming, Manufacturing, Properties: Foams, also called expanded plastics, possess inherent features that make them suitable for certain applications For instance, the thermal conductivity of a foam is lower than that of the solid polymer Also, a foamed polymer is more rigid than the solid polymer for any given weight of the material Finally, compressive stresses usually cause
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