Hyperbranched polymers containing polyhedral oligosilsequioxane branching units
The HBP Free-POSS compounds of Formula I are superior to prior HB polymers and linear polymers in space and electronic applications because they have better resistance to electrons, protons and atomic oxygen, have superior out-gassing performance, and are transparent. They are used as coatings, films, adhesives, sealants and elastomers.
1. A POSS polymer compound of formula I
[A x ] p [B y ] q Formula I
wherein:
A x is a POSS entity including closed-caged T8, T10, or T12 or an open-cage T8, T10, or T12 or another non-POSS monomer, having x number of A-type functional groups selected from hydridosilyl (Si—H), vinyl, hydroxyl or alkoxysilyl, with all functionality being the same for a given monomer;
x is an integer of 2 or more;
p is an integer of 2 or more; and
B y is a POSS entity including closed-caged T8, T10, or T12 or an open-cage T8, T10, or T12, or another non-POSS monomer, having y number of B-type functional groups that are chosen to react with the A-type functional groups and are selected from vinyl, hydridosilyl (Si—H), alkoxysilyl or hydroxyl, with all functionality being the same for a given monomer;
y is an integer of 3 or more;
q is an integer of 2 or more; and
when present, the non-POSS monomer is H(SiR 2 O) m SiR 2 H, vinyl-(SiR 2 O) m SiR 2 -vinyl, Si(OSiR 2 H) 4 , HSiR 2 CH 2 CH 2 SiR 2 H, H(Si(OR) 2 O) m Si(OR) 2 H, or vinyl(Si(OR) 2 O) m Si(OR) 2 vinyl, where R is C 1 -C 5 alkyl or C 6 -C 14 aryl, and m is 1 or more;
provided that if A and B are both POSS entities, then x does not equal y; and provided that if A and B are both POSS entities, they are not identical entities; and provided that one of A or B must be a POSS entity; and
wherein the polymer contains curable groups for further reaction, which curable groups are either initially present or have been added by a capping agent.
2. The compound of claim 1 wherein x is an integer from 2 to 11.
3. The compound of claim 1 wherein y is 3 to 12.
4. The compound of claim 1 wherein the POSS is substituted with one or more of carbosiloxane, siloxane, ether or alkyl groups.
5. The compound of claim 1 where B is a difunctional, trifunctional or tetrafunctional organosil icon compound.
6. The compound of claim 1 wherein R is methyl or phenyl.
7. The compound of claim 1 wherein the POSS polymer is a polycarbosiloxane containing POSS depicted by Formula IA
wherein: n is 2 to 1000, and R is C 1 -C 100 alkyl.
8. The compound of claim 1 wherein the POSS polymer is a HB polysiloxane containing POSS depicted by Formula IB
wherein: n is 2 to 1000, and R 1 and R 2 are independently C 1 -C 100 alkyl or C 6 -C 20 aryl.
9. A method for using a compound of Formula I as defined in claim 1 comprising reacting the polymer with curable end-groups having SiOR or SiOH, where R is defined as in claim 1 , and curing the polymer by condensation reaction, with or without a catalyst.
10. The method of claim 9 wherein the functionalized polymer is tested for transmission of light or UV radiation after coating a glass plate or forming a film on a glass plate with functionalized polymer, or tested by forming an adhesive having the functionalized polymer in a layer sandwiched between at least 2 glass plates, or tested after proton and electron radiation of the functionalized polymer sandwiched between at least 2 glass plates, or tested for its elastomeric properties having the functionalized polymer, or tested for refractive index of transmission through the functionalized polymer, or tested under vacuum for mass loss of out-gassing of the functionalized polymer.
11. A method for crosslinking a polymer of Formula I as defined in claim 1 comprising functionalizing the polymer of Formula I with curable end-groups having SiOH, SiOR, SiH, or SiCHCH 2 where R is defined as in claim 1 , and curing with linear polymers containing complimentary functionality, with or without a catalyst.
12. The method of claim 11 wherein the crosslinked polymer is tested for transmission of light or UV radiation after coating a glass plate or forming a film on a glass plate with the crosslinked polymer, or tested by forming an, adhesive having the crosslinked polymer in a layer sandwiched between at least 2 glass plates, or tested after proton and electron radiation of the crosslinked polymer sandwiched between at least 2 glass plates, or tested for its elastomeric properties having the crosslinked polymer.
13. A process for preparing a hyperbranched polymer comprising reacting:
a difunctional or polyfunctional monomer A x (a POSS entity including closed-caged T8, T10, or T12 or an open-cage T8, T10, or T12 or another non-POSS monomer, having x number of A-type functional groups, where the A-type functional groups are hydridosilyl (Si—H), vinyl, hydroxyl, chlorosilyl, or alkoxysilyl, with all functionality being the same for a given monomer, and x is an integer of 2 or more) with
a difunctional or polyfunctional monomer B y (a POSS entity including closed-caged T8, T10, or T12 or an open-cage T8, T10, or T12 or another non-POSS monomer, having y number of B-type functional groups, where B-type functional groups are chosen to react with the A-type functional groups and are vinyl, hydridosilyl (Si—H) alkoxysilyl, chlorosilyl, or hydroxyl, with all functionality being the same for a given monomer, and y is an integer of 3 or more),
which reaction product contains curable end-groups for further reaction, which curable end groups are either initially present in the reaction product or have been added by a capping agent, and
when present, the non-POSS monomer is H(SiR 2 O) m SiR 2 H, vinyl-(SiR 2 O) m SiR 2 -vinyl, Si(OSiR 2 H) 4 , HSiR 2 CH 2 CH 2 SiR 2 H, H(Si(OR) 2 O) m Si(OR) 2 H, or vinyl(Si(OR) 2 O) m Si(OR) 2 vinyl, where R is C 1 -C 5 alkyl or C 6 -C 14 aryl, and m is 1 or more; and
provided that if A x and B y are both POSS entities, then x does not equal y; and
provided that if A x and B y are both POSS entities, they are not identical entities; and
provided that one of A x or B y must be a POSS entity; and
the resulting polymer has at least two repeat units;
the process uses a catalyst (such as hydrosilylation catalysts when vinyl and hydridosilyl functional groups are being reacted, or with or without condensation catalysts when alkoxysilyl and/or chlorosilyl and/or hydroxyl functional groups are being reacted), optionally in a solvent capable of dissolving the monomers under the reaction conditions, with the monomers being mixed in a ratio containing one of the functional groups in sufficient excess so as not to produce a gel, at temperatures appropriate for the reaction, and after completion of the reaction removing residual unreacted monomers and any solvent, thereby providing the polymer product, and
optionally, further reacting the polymer with a capping agent to provide curable functional groups if not already present.