highly transparent epoxy needed

[nukedr]

I am looking for highly transparent epoxy for gluing/bonding a sandwich of optical crystal-"mirror film"-crystal together. The epoxy transparency should not age (operating temperature at 35C). The material should be strong as the sandwiches will be saw-cut later into thin 1.5mm slices/strips without breaking. The expoxy cannot be heat treated/cured as heat would damage the mirror film. Please advice.

 

[IRstuff]

Why can't you use one of the many optical cements that are on the market?

TTFN

 

[unclesyd]

Here are two suppliers of optical grade epoxies. NuSil is new to me while I've used Masterbond numerous times.
There several other supplies out there.

http://www.nusil.com/engineering-silicones/photonics/index.aspx

http://www.masterbond.com

 

[nukedr]

In our field (medical nuclear imaging), the only optical cement is from Bicron Corporation (now Saint Gobain); this cement is not strong enough to withstand sawing unless the gluing surface has a cross-section larger than 2mm by 10mm; it is a little rubber like after curing. This is why I am trying to search materials from other fields. Can you kindly suggest some alternative optical cements that I may try? Thanks

 

[Blazotron]

Hi nukedr,

I worked on a project a few years ago where we needed to bond silicon to silica, and although we did not need optical clarity, we needed room temperature cure. We found that Epotek 301 worked well, and it is also optically clear, since it was apparently designed to bond fiber optic bundles. In our tests, we were able to achieve several thousand psi of tensile strength, as long as all the parts were very clean. We also pretreated the silica components with a Silane solution to improve bonding, although this is probably not necessary for you if you just need enough strength to saw-cut. We had several sampled cut without difficulty.

Here is Epotek's optical adhesives:

http://www.epotek.com/categories.asp?ID=3#

and 301:

http://www.epotek.com/SSCDocs/datasheets/301 CFDS.PDF

Here is a silane pretreatment (Not the one I have used before, but I cant remember the brand of that one. This one similar so you get the idea.)

http://www.conservationresources.com/Main/section_31/section31_01.htm

Good luck