Terms relating to the construction and manufacture of polyolefin plastics
Polyolefin is a generic term that applies to a family of plastics belonging to the same general class of chemical compounds as paraffin wax. The principal members of this family are Polyethylene and Polypropylene whose unique properties of hinge flex life, toughness and chemical resistance make them suitable for loose leaf covers.
Copolymer
A plastic made by the polymerization of two or more monomers. Generally, copolymers of both polyethylene and polypropylene have better properties for covers.
High Density Polyethylene
Also called Linear and Low Pressure Polyethylene, HDPE is characterized by a waxy feel, extreme toughness beyond -150° F and limited hinge flex life.
Low Density Polyethylene
LDPE is
also called Branched and High Pressure Polyethylene. It is too soft and flexible to be practical for use as covers.
Modified Polyethylene
Modified Polyethylene is basically High Density Polyethylene modified with additives to improve certain properties for the cover application such as hinge flex life and feel.
Monomer
A basic compound with a very simple molecular from that is used for making plastics.
Poly-
A prefix, meaning many, that is used for any compound that has gone through polymerization.
Polymer
Also known as homopolymers, a plastic compound resulting from the polymerization of one monomer. The resulting plastic and its properties are determined primarily by the monomer used and the configuration of the molecular structures.
Polypropylene
Polypropylene is characterized by a dry feeling hard surface, brittleness at low temperature, and unlimited hinge flex life.
Polymerization
A process generally involving heat, pressure and catalysts in a reactor which joins together the molecules of the monomer into large complex molecular structures.
Tenite Polyallomer
A chemical blend of propylene and ethylene made by Eastman Chemical Product, Inc. Polyallomer tends toward the properties of polypropylene.