Holographic storage medium comprising polyfunctional epoxy monomers capable of undergoing cationic polymerization

1. A holographic recording medium comprising:

a) at least one polyfunctional epoxide monomer or oligomer which undergoes acid initiated cationic polymerization, wherein: 1) each epoxide in the monomer or oligomer is connected by a linker group comprising a siloxane to a silicon atom; or 2) each epoxide in the monomer or oligomer is connected by a linker group to a central polysiloxane ring; and each monomer or oligomer has an epoxy equivalent weight of greater than about 300 g/mole epoxide;

b) a binder which is capable of supporting cationic polymerization;

c) an acid generator capable of producing an acid upon exposure to actinic radiation; and optionally

d) a sensitizer.

2. The holographic recording medium of claim 1 , additionally comprising a difunctional epoxide monomer.

3. The holographic recording medium of claim 1 , additionally comprising a monofunctional epoxide monomer.

4. The holographic recording medium of claim 1 wherein the polyfunctional epoxide monomer or oligomer is represented by the following structural formula:

R″—Si—R′ 3

wherein each R′ independently comprises an aliphatic group substituted with epoxide, said aliphatic group being connected to the silicon atom by a linker comprising a siloxane group; and

R″ is R′ or —H, a substituted aliphatic group, an unsubstituted aliphatic group, a substituted aryl group, an unsubstituted aryl group a substituted siloxane group, an unsubstituted siloxane group, a substituted polysiloxane group or an unsubstituted polysiloxane group.

5. The holographic recording medium of claim 4 wherein each R′ comprises a group represented by the following structural formula:

wherein:

X 1 and X 2 are independently an inert linking group;

each R a is independently a substituted or unsubstituted aliphatic group or a substituted or unsubstituted aryl group; and

each R b is an aliphatic group substituted with an epoxide.