Question about epoxy resin chemistry..

On 10 Apr 2004 17:54:48 -0700, (Ryan Young) wrote:

Still more on epoxy resins....

hedge trimming
Going back to your original posting, I noticed you were looking for
TWO hardeners, and you wanted the same strength properties in both a
room temperature cure and an elevated temperature cure. I think I've
demonstrated I'm a dangerous amateur in this field, but what little I
DO know suggests that this is impossible. You might be able to
approach the properties of the high temperaure cure hardener by
post-curing the room temperature layups.

Good luck, and I hope I've been of SOME help.

Chris and Ryan.
It may be worth noting that you arent limited to epoxy resin for
layups. The production three winged Eagle-X used vinyl ester with
kevlar, glass, honeycomb and carbon fiber.
a tour through the factory was amazing for the total lack of resin
smells.
I recall also that composite nosebowls which are required to be flame
retardant use vinyl ester for that reason.
may be worth an additional search.
Stealth Pilot
Australia

Stealth Pilot wrote in message

It may be worth noting that you arent limited to epoxy resin for
layups. The production three winged Eagle-X used vinyl ester with
kevlar, glass, honeycomb and carbon fiber.
a tour through the factory was amazing for the total lack of resin
smells.
I recall also that composite nosebowls which are required to be flame
retardant use vinyl ester for that reason.
may be worth an additional search.
Stealth Pilot
Australia

Cured Vinyl Esters are no more flame retardant than normal polyesters.
Flame retardant resins have various things (antimony, silica) added
to them to make them so, which usually degrade strength properties.

Vinyl Esters MAY be a better choice for this SE Asia/Direct from the
source application for no other reason than there are not as many
choices to make!

Vinyl Esters need to be promoted to cure, and once they are promoted,
the shelf life is short, about 2 months. Do it yourself promoting is
not a good idea, toxic, reactive stuff ( cobalt naphthenate) is
involved.

The lack of resin smells may have been due to vacuum bagging, which
keeps the styrene fumes in the part! Open molding vinyl ester is just
as smelly as Polyester or Epoxy.

Vinyl Esters have mechanical properties midway between polyesters and
epoxies.

On 11 Apr 2004 21:43:28 -0700, (Ryan Young) wrote:



Cured Vinyl Esters are no more flame retardant than normal polyesters.
Flame retardant resins have various things (antimony, silica) added
to them to make them so, which usually degrade strength properties.

Vinyl Esters MAY be a better choice for this SE Asia/Direct from the
source application for no other reason than there are not as many
choices to make!

Vinyl Esters need to be promoted to cure, and once they are promoted,
the shelf life is short, about 2 months. Do it yourself promoting is
not a good idea, toxic, reactive stuff ( cobalt naphthenate) is
involved.

The lack of resin smells may have been due to vacuum bagging, which
keeps the styrene fumes in the part! Open molding vinyl ester is just
as smelly as Polyester or Epoxy.

Vinyl Esters have mechanical properties midway between polyesters and
epoxies.

thanks.
Stealth Pilot