[daenerys]

The chemical formula of this epoxy resin is C18H21ClO3. When I looked up the structure, I was confused because it has what seems like two separate structures. The IUPAC name for it is 2-(chloromethyl)oxirane;4[2-(4-hydroxyphenyl)propan-2-yl]phenol. I guess that's why there's a semicolon, because it has two different stuctures that somehow exist as a single unit.
I am a student of mechanical engineering and we need to use this resin but I don't understand the structure and why it is like that at all! Help please?
Here's what it looks like:

[Borek]

Chemical formula for polymers should never look like the one you listed - they are much larger, and typically their formulas are given as y_n (or x(y)_nz if there are different endings), to show there is a chain and variable length present.

Epoxy resins are made of two substances - so technically they are copolymers. You have these two substances on your image, now it is about finding out how they react during setting.

[opsomath]

The actual resin is formed by these two chemicals reacting with each other to form a polymer.