![]() |
|||||
![]() |
![]() |
||||
![]() |
![]() |
||||
![]() |
|||||
Novolac Epoxy Resins:
Novolac epoxy resins generally
contain multiple epoxide groups. The number of epoxide groups per molecule
depends upon the number of phenolic hydroxyl groups in the starting phenolic
novolac resin, the extent to which they reacted and the degree of low molecular
species being polymerised during synthesis. The multiple epoxide groups
allow these resins to achieve high cross-link density resulting in excellent
temperature, chemical and solvent resistance. Novolac epoxy resins are widely
used to formulate the moulding compounds for microelectronics packaging
because of their superior performance at elevated temperature, excellent
mouldability, and mechanical properties, superior electrical properties,
and heat and humidity resistance.
Novolac Epoxy
Resins for flooring
Almost 90 % of epoxy resins used for industrial epoxy flooring are Bisphenol
A epoxies.Novolac epoxy resins have greatly improved chemical and heat resistance
compared to the much more common Bis A epoxies.They have higher heat distortion
temperatures. Generally Bis A epoxies will begin to soften in the 50-70
degree °C range. Novolac epoxies initially raise this value by about
14 degrees °C . All epoxies will reharden when the elevated temperatures
fall below this transition temperature. However, Bis Novolac epoxies will
continue to cure when exposed to temperatures of about 65 degrees °C
for a few hours. After this 'additional curing' they generally can withstand
about 150 degrees °C (dry environment) without problems.
The chemical resistance test shows that epoxy floor made with good quality
Bis A epoxy are persistant to 70% sulfuric acid and epoxy floor laid with
novolac epoxy are persistant
to 98% sulfuric acid.
Because of all this improved characteristics Novolac epoxy resins are much
more expensive than regular epoxies.
More about epoxy resins you can find in "The Best Web Epoxy Links" eBook.
Links
Epoxy Home
Terms
Contact
Copyright
©2013 EpoxyandEpoxyFlooring.com. All
Rights Reserved.