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Cyclic olefin copolymer (COC) is an amorphous polymer made by several polymer manufacturers. COC is a relatively new class of polymers as compared to commodities such as polypropylene and polyethylene. This newer material is used in a wide variety of applications including packaging films, lenses, vials, displays, and medical devices.
An alternative process involving copolymerization with ethylene is used to make cyclic olefin copolymers (COC). These two types of cyclic olefin polymers were historically referred to as COC but are now recognized as distinct classes of polymers formed from different polymerization processes.
For example, an alternating copolymer synthesized by radical polymerization is a sequence-controlled polymer, even if it is also a non-uniform polymer, in which chains have different chain-lengths and slightly different compositions. [2] A biopolymer (for example a protein) with a perfectly-defined primary structure is also a sequence ...
Corcoran station, an Amtrak station in California, United States whose station code is COC; Cup of China, a figure skater competition; Cyclic olefin copolymer, the chemical name for a plastic engineering resin; Continuum of Care, a program designed to promote community-wide commitment to the goal of ending homelessness
To make polyoxymethylene copolymer, formaldehyde is generally converted to trioxane (specifically 1,3,5-trioxane, also known as trioxin). [18] This is done by acid catalysis (either sulfuric acid or acidic ion-exchange resins ) followed by purification of the trioxane by distillation and/or extraction to remove water and other active hydrogen ...
The unique characteristic of PPO block, which is hydrophobic at temperatures above 288 K and is soluble in water at temperatures below 288 K, leads to the formation of micelle consisting of PEO-PPO-PEO triblock copolymers. Some studies report that the hydrophobic core contains PPO block, and a hydrophilic corona consists of PEO block.
Copolymers [ edit ] For heterogeneous surfaces (consisting of two or more different types of material), the contact angle of a drop of liquid at each point along the three phase contact line with a solid surface is a result of the surface tension of the surface at that point.
Figure 1: Example of a (a) diblock copolymer, (b) gradient copolymer and (c) random copolymer. In polymer chemistry, gradient copolymers are copolymers in which the change in monomer composition is gradual from predominantly one species to predominantly the other, [1] unlike with block copolymers, which have an abrupt change in composition, [2] [3] and random copolymers, which have no ...