Low melting and low viscosity thermoset matrix resins from the Z configuration of polyhydroxy stilbenes
View Patent ↗The invention generally relates to novel poly-substituted cis stilbenes, their synthesis, their purification, and their use in thermoset resins. These novel cis stilbenes give rise to thermoset resins with greatly improved processing characteristics such as lower melting temperature and lower viscosity; resulting in polymers and composites having greatly improved thermal stability.
1. A process for the selective extraction of cis-polyhydroxystilbenes of more than 85% purity from a fraction of stilbenes, comprising:
isomerizing trans-stilbenes in said fraction of stilbenes to cis-stilbenes;
extracting cis-polyhydroxystilbenes from said isomerized fraction of stilbenes with a solvent;
wherein said solvent is comprised of one or more solvents in which cis-stilbenes are soluble and trans-stilbenes are insoluble;
and
filtering out any insoluble trans-stilbenes and evaporating the solvent extract under reduced pressure to obtain cis-polyhydroxystilbenes.
2. A process for the selective extraction of cis-polyhydroxystilbenes from a fraction of stilbenes, comprising:
extracting cis-polyhydroxystilbenes from said fraction of stilbenes with a solvent; and
filtering and evaporating the solvent extract under reduced pressure to exclusively obtain cis-polyhydroxystilbenes
wherein the selective solvent extraction yields a cis-polyhydroxystilbenes concentration greater than about 95%.
3. The process of claim 2 wherein said solvent comprises dipropyl ether, dibutyl ether, methyl tert-butyl ether, or diisopropyl ether.
4. The process of claim 2 wherein said solvent comprises a combination of a first solvent and a second solvent; wherein the ratio of the first solvent to the second solvent is between about 3:1 to about 5:1.
5. The process of claim 4 wherein the combination of first solvent/second solvent is selected from the group of combinations consisting of benzene/acetonitrile, ethylbenzene/acetonitrile, toluene/ethyl acetate, benzene/ethyl acetate, ethylbenzene/ethyl acetate.
6. The process of claim 2 wherein the solvent is a dialkyl ether.
7. A composition comprising the formula:
where m is 0, 1, or 2 and n is 1 or 2;
where R is —OH, cyanate ester (—O—C≡N), glycidyl ether (—O—CH 2 -2-oxirane), acrylate (—O—CO—C═CH 2 ), or methacrylate (—O—CO—C(CH 3 )CH 2 ); and,
where R 2 is H, or methoxy.
8. The composition of claim 7 where R is OH and R 2 is H.
9. The composition of claim 7 where R is —O—C≡N and R 2 is H.
10. The composition of claim 7 where R is —O—CH 2 -2-oxirane and R 2 is H.
11. The composition of claim 7 where R is —O—CO—C(CH 3 )CH 2 and R 2 is H.
12. The composition of claim 7 where R is —O—CO—C═CH 2 and R 2 is H.
13. The composition of claim 9 comprising cis 3,4′,5-tricyanatostilbene, cis 3,5-dicyanatostilbene, cis 4,4′-dicyanatostilbene, cis 3,3′-dicyanatostilbene, cis 3,4′-dicyanatostilbene, cis 3,3′,5,5′-tetracyanatostilbene, cis 3,3′,5′-tricyanatostilbene, cis 2,3′,4,5′-tetracyanatostilbene, or cis 3,3′-dicyanato-5-methoxystilbene.
14. The composition of claim 10 comprising cis 3,4′,5-triglycidyloxystilbene, cis 3,5-diglycidyloxystilbene, cis 4,4′-diglycidyloxystilbene, cis 3,3′-diglycidyloxystilbene, cis 3,4′-diglycidyloxystilbene, cis 3,3′,5,5′-tetraglycidyloxystilbene, cis 3,3′,5′-triglycidyloxystilbene, cis 2,3′,4,5′-tetraglycidyloxystilbene, or cis 3,3′-diglycidyloxy-5-methoxystilbene.
15. The composition of claim 11 comprising cis 3,4′,5-trihydroxystilbene trimethacrylate, cis 3,5-dihydroxystilbene dimethacrylate, cis 4,4′-dihydroxystilbene dimethacrylate, cis 3,3′-dihydroxystilbene dimethacrylate, cis 3,4′-dihydroxystilbene dimethacrylate, cis 3,3′,5,5′-tetrahydroxystilbene tetramethacrylate, cis 3,3′,5′-trihydroxystilbene trimethacrylate, cis 2,3′,4,5′-tetrahydroxystilbene tetramethacrylate, or cis 3,3′-dihydroxy-5-methoxystilbene dimethacrylate.
16. The composition of claim 12 comprising cis 3,4′,5-trihydroxystilbene triacrylate, cis 3,5-dihydroxystilbene diacrylate, cis 4,4′-dihydroxystilbene diacrylate, cis 3,3′-dihydroxystilbene diacrylate, cis 3,4′-dihydroxystilbene diacrylate, cis 3,3′,5,5′-tetrahydroxystilbene tetraacrylate, cis 3,3′,5′-trihydroxystilbene triacrylate, cis 2,3′,4,5′-tetrahydroxystilbene tetraacrylate, or cis 3,3′-dihydroxy-5-methoxystilbene diacrylate.