can somebody explain the difference?

General Discussion
1

between epoxy polymerization and the hardening of polyester?

i know the molecules of epoxy are longer, and crosslinked... but

polyester is hardened somehow, dont the molecules link up? how does it harden then? and if it hardens, then is there a molecular bond from molecule to molecule??

would love to explain why polyester is so weak [and osmosis prone, big gaps between bonds?]

cheers

 

2

Check this (sorry, it’s in French…)

http://images.google.fr/imgres?imgurl=http://www.esprit-marine.com/Images/Epoxychain.jpg&imgrefurl=http://www.esprit-marine.com/Francais/Technical/Epoxy_FR.html&usg=__-lgw7JK12Tgv0R1zFiQivU0EjTU=&h=200&w=123&sz=9&hl=fr&start=12&um=1&tbnid=dgE62c3JL8Gv0M:&tbnh=104&tbnw=64&prev=/images%3Fq%3Dcha%25C3%25AEne%2Bmol%25C3%25A9culaire%2Bpolyester%26hl%3Dfr%26safe%3Doff%26client%3Dfirefox-a%26channel%3Ds%26rls%3Dorg.mozilla:fr:official%26sa%3DN%26um%3D1

3

Sorry, there is an English version:

http://images.google.fr/imgres?imgurl=http://www.esprit-marine.com/Images/Epoxychain.jpg&imgrefurl=http://www.esprit-marine.com/Francais/Technical/Epoxy_FR.html&usg=__-lgw7JK12Tgv0R1zFiQivU0EjTU=&h=200&w=123&sz=9&hl=fr&start=12&um=1&tbnid=dgE62c3JL8Gv0M:&tbnh=104&tbnw=64&prev=/images%3Fq%3Dcha%25C3%25AEne%2Bmol%25C3%25A9culaire%2Bpolyester%26hl%3Dfr%26safe%3Doff%26client%3Dfirefox-a%26channel%3Ds%26rls%3Dorg.mozilla:fr:official%26sa%3DN%26um%3D1

4

Apparently, it can be explained – but only in French.  :expressionless: