Some Manufacturers sell co-poly saying it's a single line coated with FC. Izorline is not coated with FC? SO what is co-poly line?

In their case - it's a blend of different polymers.

Simply, copoly is is a mix of 2 or more polymers.  Fluorocarbon is a polymer.  Nylon is a polymer.  Then each of those has variations on a theme.  There might even be some polymers that are used that aren’t fluoro or nylon (I can’t say).  Then there is a case of how they are mixed.  Coated, blended, twisted, etc.  Lots of options.  A fluoro coated nylon will give you abrasion resistance with a soft core for a little better flexibility than the coating would have allowed on its own.  Mixed/blended will give you a set of properties of its own depending on the design.  

The whole fishing line definitions can be confusing.

Monofilament line means a single filament. fluorocarbon line is a single filament line but not called Monofilament, that term is reserved for Nylon single filament line. 
CoPolymer should be a blend of 2 polymers. The most common being Nylon and polyester. 
CoExtruded line is a monofilament line with Fluorocarbon line extruded onto the core monofilament in the form of a jacket.

Yo-Zuri Hybrid line is the correct terminology it’s not a blend of 2 polymers.

Marketing and companies trying to group line into 2 categories in lieu of 3 or more creates the confusion. 
Tom

13 hours ago, WRB-2.0 said:

The whole fishing line definitions can be confusing.

Monofilament line means a single filament. fluorocarbon line is a single filament line but not called Monofilament, that term is reserved for Nylon single filament line. 
CoPolymer should be a blend of 2 polymers. The most common being Nylon and polyester. 
CoExtruded line is a monofilament line with Fluorocarbon line extruded onto the core monofilament in the form of a jacket.

Yo-Zuri Hybrid line is the correct terminology it’s not a blend of 2 polymers.

Marketing and companies trying to group line into 2 categories in lieu of 3 or more creates the confusion. 
Tom

Thank you Toms. Yes it is very confusing. I have been using straight FC Invizx. Very good line, but gets expensive. Tried braid with a leader and just a pain to change leaders, especially fishing Neds and gettin hung up.

 

14 hours ago, casts_by_fly said:

Simply, copoly is is a mix of 2 or more polymers.  Fluorocarbon is a polymer.  Nylon is a polymer.  Then each of those has variations on a theme.  There might even be some polymers that are used that aren’t fluoro or nylon (I can’t say).  Then there is a case of how they are mixed.  Coated, blended, twisted, etc.  Lots of options.  A fluoro coated nylon will give you abrasion resistance with a soft core for a little better flexibility than the coating would have allowed on its own.  Mixed/blended will give you a set of properties of its own depending on the design.  

Thank you.

Think of copolymer as a chain with alternating links being a different type steel.  One type of steel offers more strength, and the other offers slightly more flex. If more resistance to corrosion is desired, it may be coated with a different material that doesn’t compromise the desired properties of the links.

A copolymer line (chain) is made by linking molecules (links) of 2 types of, say, nylon with each having slightly different properties (e.g., strength and stretch).  A coating like fluorocarbon may be added to provide resistance to abrasion and/or water absorption.