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End Market:
Any product that utilizes post-consumer plastic plastic
in its manufacture. (Adapted from Modern Plastics Encyclopedia
1995)
End Product:
A fabricated value-added item that does not include
Bales, flake or pellets. (1995 post-consumer plastic
Plastics Recycling/Recovery Rate Survey, Glossary of
Terms, R.W. Beck & Associates).
Endocrine:
For more information on the theory of endocrine disruption
go to the Canadian Chemical Producers Association, the
Chemical Manufacturers Association, the Chlorine Chemistry Council or the Bisphenol-A Web Site
sponsored by the Global Bisphenol-A Industry Group of
The Society of the Plastics Industry, Inc. and the European
Chemical Industry Council (CEFIC).
Energy Recovery:
The process of recovering the thermal energy produced
when fuels are converted to gases and residues through
the combustion process. The thermal energy generally
is recovered through the use of heat exchangers that
extract the energy from the hot combustion gases. Heat
exchangers can be air to air units similar to those
used in residential or commercial hot air heating systems
or air to water/steam units (boilers) that can be designed
to generate either hot water or steam, similar to residential
and commercial hot water and steam generation heating
systems. Large electric power production facilities,
including modern waste-to-energy plants, that supply
needed power to our homes, hospitals and factories,
maximize thermal energy recovery efficiency through
the utilization of high temperature, high pressure steam
generating boilers that recover both the radiant energy
from the combustion process inside the furnace as well
as the energy in the hot combustion gases. The high
heating value of plastics makes them a valuable source
of energy that can be readily recovered in modern waste-to-energy
plants. (Tchobanoglous, George, Hilary Theisen and Rolf
Eliassen, "Solid Wastes, Engineering Principles and
Management Issues," McGraw-Hill, Inc., New York, 1977;
Gershman, Brickner & Bratton, Inc., "Small-Scale
Municipal Solid Waste Energy Recovery Systems," Van
Nostrand Reinhold Company, New York, 1986).
Environmental
Marketing Guidelines:
U.S. Federal Trade Commission (FTC) Guides for the Use
of Environmental Marketing Claims, issued in July, 1992,
are voluntary guidelines for product manufacturers using
environmental advertising and marketing. They are intended
to help prevent misleading environmental marketing claims.
(Environmental Packaging; U.S. Guide to Green Labeling,
Packaging and Recycling. Thompson Publishing Group,
October 1995).
Extrusion:
One of the most common plastics processing techniques
covering a vast range of applications in which resins
are melted, heated and pumped for processing. Extrusion
machines accomplish these tasks by means of one or more
internal screws. In extrusion, the material to be processed
is sheared between the root of the screw and the wall
of the barrel that surround it. This process produces
frictional energy that heats and melts the substance
as it is conveyed down the barrel. Melted extrudate
from the machine is further processed after the extrusion
phase, which typically produces pellets, sheet, cast
film, blown film, fibers, coatings, pipes, profiles
or molded parts. (Modern Plastics Encyclopedia 1995)
Elastomer
A polymer with the properties of rubber. Polymers that
can be formulated as elastomers are polyurethane, butyl
rubber, silicones and specially treated ethylene-propylene
copolymers.
End-group
A constitutional unit with only one attachment to a
chain
Environmental stress
cracking
Under certain conditions of stress and environment like
oils, detergents or soaps, ethylene plastics may fail
mechanically by cracking. This phenomenon is called
environmental stress cracking resistance (ESCR). ESCR
properties can be tested in accelerated tests by presence
of starter notches, surface active agent, elevated temperature
and mechanical loading. Test result is the time when
50 % of the samples have failed.
Expanded polymer
Alternative name for cellular polymer, but the term
is often restricted to those cases where the material
has been produced by allowing a gas to expand within
a polymer melt and then cololing the melt, thus trapping
the gas bubbles in the now solid polymer.
The gas is produced either by the
injection under pressure or by the chemical decomposition,
usually induced by the high temperatures of melt processing
of a blowing agent.
Extruder
Equipment for melting, pressurising and homogenising
plastics by means of a rotating screw. Different configurations
are possible; the most simple one being a single screw
extruder mainly used for conversion processes like cast
film extrusion, fibre spinning, film blowing or pipe
and profile extrusion. For more demanding applications
like compounding of polymer powder before pelletization
or the mixing of polymers, twin screw extruders are
used where the two normally intermeshing screws can
be moved in a corotating (same direction) or counterrotating
(opposite direction) fashion. These machines normally
contain different mixing elements, most important being
kneading blocks for the local creation of extensional
flow.
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Plastic
Brief
