Questions on UV curing polyester resins.
 

Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

2) Once the UV light has initiated the polymerization, will it spread
through the layup even into places where the light did not
penetrate? *I'm thinking, for instance about the underside
of carbon fiber cloth.

Thanks.

--

FF

Questions on UV curing polyester resins.
 

Questions on UV curing polyester resins.
 

On Mar 14, 12:31*pm, Paul Oman wrote:
wrote:
Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

*2) Once the UV light has initiated the polymerization, will it spread
* * * through the layup even into places where the light did not
* * * penetrate? *I'm thinking, for instance about the underside
* * * of carbon fiber cloth.

*Thanks.

--

FF

it makes more sense to use thermo set epoxies. Stronger, better bond,
probably cheaper.
epoxies will not dissolve foam

Thermo set meaning that they don't begin to cure until they are
heated?
I ask because I am looking for a very long working time.

If so, do you have a recommendation?

Otherwise, can you answer the first question? I was quite aware of
the
other issues.

Questions on UV curing polyester resins.
 

On Tue, 16 Mar 2010 01:35:54 -0700 (PDT), wrote:

On Mar 14, 12:31*pm, Paul Oman wrote:
wrote:
Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

*2) Once the UV light has initiated the polymerization, will it spread
* * * through the layup even into places where the light did not
* * * penetrate? *I'm thinking, for instance about the underside
* * * of carbon fiber cloth.

*Thanks.

--

FF

it makes more sense to use thermo set epoxies. Stronger, better bond,
probably cheaper.
epoxies will not dissolve foam

Thermo set meaning that they don't begin to cure until they are
heated?
I ask because I am looking for a very long working time.

If so, do you have a recommendation?

Otherwise, can you answer the first question? I was quite aware of
the
other issues.


I believe that any of the polymer based resins will destroy
polystyrene foam. At least that was what I was told years ago, but I
must admit that I never tested it.

By the way, UV curing polyester is not essentially a different resin.
It is polyester resin with a UV catalyst added to it and it is the
resin that attacks the foam.

I'm not a board builder but I believe that the polyester boards are
made using polyurethane foam.

Have a look at
http://www.compositesworld.com/artic...s-demonstrated

for more details of using UV polyester

It apparently is possible to laminate carbon fiber with some cautions.

What are you building?

Cheers,

Bruce

Questions on UV curing polyester resins.
 

On Tue, 16 Mar 2010 13:42:41 -0400, Paul Oman
wrote:

wrote:
On Mar 14, 12:31 pm, Paul Oman wrote:

wrote:

Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

2) Once the UV light has initiated the polymerization, will it spread
through the layup even into places where the light did not
penetrate? I'm thinking, for instance about the underside
of carbon fiber cloth.

Thanks.

--

FF

it makes more sense to use thermo set epoxies. Stronger, better bond,
probably cheaper.
epoxies will not dissolve foam


Thermo set meaning that they don't begin to cure until they are
heated?
I ask because I am looking for a very long working time.

If so, do you have a recommendation?

Otherwise, can you answer the first question? I was quite aware of
the
other issues.

----------------------
thermo set means a chemical reaction between parts a and b and these
reactions produce heat. This is how epoxies work. You can get slow
epoxy curing agents and you can also slow down the reaction by working
in cooler temps.

paul oman - progressive epoxy polymers inc

More importantly, it means crosslinks between molecules, as when parts
a and b or their reaction intermediates have more than two reaction
sites per molecule. This leads to a network molecule with no melting
point, although it will decompose with enough heat. I made a variety
of thermoplastics (more or less linear molecules) using epoxy and a
reactant in my old r&d job.

Pete Keillor

Questions on UV curing polyester resins.
 

On Mar 16, 5:31*am, Bruce wrote:
On Tue, 16 Mar 2010 01:35:54 -0700 (PDT), wrote:
On Mar 14, 12:31*pm, Paul Oman wrote:
wrote:
Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

*2) Once the UV light has initiated the polymerization, will it spread
* * * through the layup even into places where the light did not
* * * penetrate? *I'm thinking, for instance about the underside
* * * of carbon fiber cloth.

*Thanks.


it makes more sense to use thermo set epoxies. Stronger, better bond,
probably cheaper.
epoxies will not dissolve foam

Thermo set meaning that they don't begin to cure until they are
heated?
I ask because I am looking for a very long working time.

If so, do you have a recommendation?

Otherwise, can you answer the first question? *I was quite aware of
the
other issues.

I believe that any of the polymer based resins will destroy
polystyrene foam. ...

Yes, that is correct.


By the way, UV curing polyester is not essentially a different resin.
It is polyester resin with a UV catalyst added to it and it is the
resin that attacks the foam.

Good to know.


I'm not a board builder but I believe that the polyester boards are
made using polyurethane foam.

It is quite correct that polyester and epoxy resins, mineral spirits,
gasoline and
various other solvents do not attack urethane foams the way they do
styrene
foams.

Some epoxies (e.g. WEST system) attack polystyrene. Most do not.


Have a look athttp://www.compositesworld.com/articles/techonologies-for-uv-curing-o...

for more details of using UV polyester


Thanks, that answers my question.


What are you building?


I'm working on plans for a glider. I'm interested in a long working
time.

Questions on UV curing polyester resins.
 

On Mar 16, 1:42*pm, Paul Oman wrote:
wrote:
On Mar 14, 12:31 pm, Paul Oman wrote:

wrote:

Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

*2) Once the UV light has initiated the polymerization, will it spread
* * * through the layup even into places where the light did not
* * * penetrate? *I'm thinking, for instance about the underside
* * * of carbon fiber cloth.

*Thanks.

--

FF

it makes more sense to use thermo set epoxies. Stronger, better bond,
probably cheaper.
epoxies will not dissolve foam

Thermo set meaning that they don't begin to cure until they are
heated?
I ask because I am looking for a very long working time.

If so, do you have a recommendation?

Otherwise, can you answer the first question? *I was quite aware of
the
other issues.

----------------------
thermo set means a chemical reaction between parts a and b and these
reactions produce heat. This is how epoxies work. *You can get slow
epoxy curing agents and you can also slow down the reaction by working
in cooler temps.

That is correct. The longest working times available are only about
a hour or so though, right? Low temperatures might extend that, but
would also thicken it making it harder to get good penetration of
fabric.

Questions on UV curing polyester resins.
 

In article ,
says...

On Mar 16, 1:42*pm, Paul Oman wrote:
wrote:
On Mar 14, 12:31 pm, Paul Oman wrote:

wrote:

Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

*2) Once the UV light has initiated the polymerization, will it spread
* * * through the layup even into places where the light did not
* * * penetrate? *I'm thinking, for instance about the underside
* * * of carbon fiber cloth.

*Thanks.

--

FF

it makes more sense to use thermo set epoxies. Stronger, better bond,
probably cheaper.
epoxies will not dissolve foam

Thermo set meaning that they don't begin to cure until they are
heated?
I ask because I am looking for a very long working time.

If so, do you have a recommendation?

Otherwise, can you answer the first question? *I was quite aware of
the
other issues.

----------------------
thermo set means a chemical reaction between parts a and b and these
reactions produce heat. This is how epoxies work. *You can get slow
epoxy curing agents and you can also slow down the reaction by working
in cooler temps.

That is correct. The longest working times available are only about
a hour or so though, right? Low temperatures might extend that, but
would also thicken it making it harder to get good penetration of
fabric.

With respect to Paul, who spends a lot of time here on this board helping I
used to get slow cure hardener from Larry at Raka in Florida. I am not sure if
Paul has a similar option.

Did you ever say what it is you are trying to make?

Scotty from SmallBoats.com

--
Team Rowdy Mouse, Banned from the Mall for life!

Questions on UV curing polyester resins.
 

On Mar 16, 7:46*pm, I am Tosk wrote:
In article ,
says...





On Mar 16, 1:42*pm, Paul Oman wrote:
wrote:
On Mar 14, 12:31 pm, Paul Oman wrote:

wrote:

Two questions for people with knowledge or experience with the UV
curing polyester resins:

1) Are they (any of them) compatible with polystyrene foam?

*2) Once the UV light has initiated the polymerization, will it spread
* * * through the layup even into places where the light did not
* * * penetrate? *I'm thinking, for instance about the underside
* * * of carbon fiber cloth.

*Thanks.

--

FF

it makes more sense to use thermo set epoxies. Stronger, better bond,
probably cheaper.
epoxies will not dissolve foam

Thermo set meaning that they don't begin to cure until they are
heated?
I ask because I am looking for a very long working time.

If so, do you have a recommendation?

Otherwise, can you answer the first question? *I was quite aware of
the
other issues.

----------------------
thermo set means a chemical reaction between parts a and b and these
reactions produce heat. This is how epoxies work. *You can get slow
epoxy curing agents and you can also slow down the reaction by working
in cooler temps.

That is correct. *The longest working times available are only about
a hour or so though, right? *Low temperatures might extend that, but
would also thicken it making it harder to get good penetration of
fabric.

With respect to Paul, who spends a lot of time here on this board helping I
used to get slow cure hardener from Larry at Raka in Florida. I am not sure if
Paul has a similar option.

Did you ever say what it is you are trying to make?


I'm planning on a glider.

Questions on UV curing polyester resins.
 

On Mar 16, 7:46*pm, I am Tosk wrote:
In article ,


Did you ever say what it is you are trying to make?



I'm looking at materials and techniques that would be useful for a
homebuilt glider.

--

FF