Ferroelectric liquid crystal (FLC) polymers
A system having a ferroelectric liquid host material and a small amount of polymer additive is provided. In an embodiment, the polymer additive improves the physical characteristics of the system. In an embodiment, the system can be used in FLC applications.
1. A ferroelectric liquid crystal composition, comprising:
a ferroelectric liquid crystal host; and between 0.01 and 5 wt % of a side group liquid crystal polymer, wherein the side group liquid crystal polymer is polymerized and purified prior to introduction into the ferroelectric liquid crystal host, is not crosslinked and has the structure (FX1):
wherein PX is a polymer; W is a spacer; and LC is a liquid crystal, wherein the side group liquid crystal polymer is soluble in the ferroelectric liquid crystal host at a temperature at which the ferroelectric liquid crystal host is ferroelectric.
2. The ferroelectric liquid crystal composition of claim 1 , wherein the side group liquid crystal polymer has the structure (FX2):
wherein PX is
[—(CH 2 —CH—S) n —], [—(NH—CH—C(═O)) n —], [—(—C(═O)—N—C(═O)) n —], [—(Si(CH 2 )—O) n —], [—(CH 2 —CH(C(O)═O) n —], [—(CH 2 —C(CH 3 )(C(O)═O) n —], [—(CH 2 CH) n —], [—(CH(CH 2 CH 2 )) n —] or [—(CH 2 —CH(CH 2 CH 2 )) n —] where in each PX n is independently an integer between 50 to 10000;
W is —(O) b —(CR 13 R 14 ) x —(O) b —FX—(O) b —(CR 15 R 16 ) y —(O) b —, where x and y are each independently integers from 0 to 20;
FX is a spacer selected from —S—, —S(═O)—, —O—, —C(═O)—,
where q is an integer from 0 to 10;
t is an integer from 1 to 10;
each b is independently 0 or 1; and
R 3 , R 4 , R 5 and R 6 are each independently selected from optionally substituted C 1 -C 6 alkyl, where the optional substituents are one or more halogens;
R 13 , R 14 , R 15 and R 16 are each independently hydrogen or halogen;
each L is independently selected from: —O—C(═O)—, —C(═O)—O—, —C═C—, —C≡C—, —(CH 2 ) u —; and a single bond; where u is an integer from 1 to 10;
R 1 and R 2 are each independently selected from:
where X 1 , X 2 , X 3 and X 4 are independently hydrogen, halogen, methoxy, C 1 -C 3 alkyl or —CN; where (a) each Z and each Y is CH, or (b) each Z is N and each Y is CH, or (c) each Y is N and each Z is CH;
R 7 and R 8 are each independently hydrogen, halogen, and —(O) v —(CH 2 ) p —CH 3 where p is an integer from 0 to 20 and v is 0 or 1;
R 30 and R 31 are each independently hydrogen or halogen.
3. The ferroelectric liquid crystal composition of claim 1 , wherein in the side group liquid crystal polymer PX is a polymer having the formula:
where n is an integer from 50 to 10,000.
4. The ferroelectric liquid crystal composition of claim 2 , wherein in the side group liquid crystal polymer each L is independently selected from:
—O—C(═O)—, —C(═O)—O—, —(CH 2 ) u —; and a single bond; where u is an integer from 1 to 10;
W is —(CH 2 ) x —FX—(CH 2 ) y —; x and y are each independently integers from 0 to 20;
FX is a spacer selected from —S—,
where q is an integer from 0 to 10;
where t is an integer from 1 to 10;
R 3 , R 4 , R 5 and R 6 are each independently selected from hydrogen and C1-C6 alkyl;
PX is a polymer having the structure:
where n is an integer from 50 to 10,000;
R 1 and R 2 are each independently selected from:
where X 1 , X 2 , X 3 and X 4 are independently hydrogen, halogen or —CN; where (a) each Z and each Y is CH, or (b) each Z is N and each Y is CH, or (c) each Y is N and each Z is CH;
R 7 and R 8 are independently —(O) v —(CH 2 ) p —CH 3 where p is an integer from 0 to 20;
v is 0 or 1; and
R 30 and R 31 are each independently hydrogen or halogen.
5. The ferroelectric liquid crystal composition of claim 1 , wherein the side group liquid crystal polymer has the structure (FX3):
where n is an integer from 200 to 1,000.
6. The ferroelectric liquid crystal composition of claim 1 , wherein the side group liquid crystal polymer has the structure (FX4):
7. The ferroelectric liquid crystal composition of claim 2 , wherein in the side group liquid crystal polymer,
when L-R 2 is
X 3 and R 31 , along with the carbon atoms on the rings to which they are attached, form a five-membered ring, so that LC has the structure:
where each R is independently C1-C6 alkyl.
8. The ferroelectric liquid crystal composition of claim 1 , wherein in the side group liquid crystal polymer, LC has the structure
where each R is independently a C1-C6 alkyl.
9. The ferroelectric liquid crystal composition of claim 1 , wherein in the side group liquid crystal polymer, LC has the structure (FX5a), (FX6a), (FX7a) or (FX8a):
where Ar is selected from phenyl, pyrimidine, pyridine, and cyclohexyl having an optional O or S heteroatom in the ring;
w is an integer from 0 to 3;
R 20 , R 21 , R 22 , R 23 and R 24 are each independently
—H, —F, —Cl, —Br, —CN, —CF 3 , —OCF 3 , —OCH 3 , C1-C6 optionally substituted alkyl where the optional substituents are one or more halogens, and C1-C6 alkoxy;
RG is selected from the group consisting of:
where R 25 is C1-C6 alkyl or C1-C6 alkoxy;
PX is
[—(CH 2 —CH—S) n —], [—(NH—CH—C(═O)) n —], [—(—C(═O)—N—C(═O)) n —], [—(Si(CH 2 )—O) n —], [—(CH 2 —CH(C(O)═O) n —], [—(CH 2 —C(CH 3 )(C(O)═O) n —], [—(CH 2 CH) n —], [—(CH(CH 2 CH 2 )) n —] or [—(CH 2 —CH(CH 2 CH 2 )) n —] where in each PX n is independently an integer between 50 to 10000;
W is —(O) b —(CR 13 R 14 ) x —(O) b —FX—(O) b —(CR 15 R 16 ) y —(O) b —, where x and y are each independently integers from 0 to 20;
FX is a spacer selected from —S—, —S(═O)—, —O—, —C(═O)—,
where q is an integer from 0 to 10;
t is an integer from 1 to 10;
each b is independently 0 or 1; and
R 3 , R 4 , R 5 and R 6 are each independently selected from optionally substituted C 1 -C 6 alkyl, where the optional substituents are one or more halogens;
R 13 , R 14 , R 15 and R 16 are each independently hydrogen or halogen;
R 27 is C1-C20 alkyl, C1-C20 alkoxy, -Q(CH 2 ) f (CF 2 ) g CF 3 or -Q(CH 2 ) f (SiMe 2 )(CH 2 ) g (CF 2 ) g CF 3 ;
where Q is O, S, CO, CO 2 or a single bond;
each f and g are independently integers from 0 to 10;
each T is independently CH or N;
where when T is CH, T is optionally substituted with halogen, —CF 3 , —OCF 3 , —CN, —OCH 3 or —CH 3 ;
R 2 is selected from:
where X 1 , X 2 , X 3 and X 4 are independently H or halogen; where (a) each Z and each Y is CH, or (b) each Z is N and each Y is CH, or (c) each Y is N and each Z is CH;
R 7 and R 8 are independently —(O) v —(CH 2 ) p —CH 3 where p is an integer from 0 to 20 and v is 0 or 1;
R 9 is
where X 1 , X 2 , X 3 and X 4 are independently H or halogen; where (a) each Z and each Y is CH, or (b) each Z is N and each Y is CH, or (c) each Y is N and each Z is CH; and each L is independently selected from: —O—C(═O)—, —C(═O)—O—, —C═C—, —C≡C—, —(CH 2 ) u —; and a single bond; where u is an integer from 1 to 10.
10. The ferroelectric liquid crystal composition of claim 9 , wherein the side group liquid crystal polymer has the structure (FX9), (FX10) or (FX9A):
where n is an integer from 500 to 1,000 and a is an integer from 5 to 9.
11. The ferroelectric liquid crystal composition of claim 9 , wherein in the side-group liquid crystal polymer, PX is a polymer having the structure:
where n is an integer from 50 to 10,000.
12. An optical device comprising:
two opposing electrode surfaces;
the ferroelectric liquid crystal composition of claim 1 disposed therebetween, wherein the optical device has improved contrast as compared to an optical device containing no side group liquid crystal polymer.
13. A method of preparing a ferroelectric liquid crystal composition, comprising:
contacting a ferroelectric liquid crystal host with between 0.01 and 5 wt % of a side group liquid crystal polymer which is soluble in the ferroelectric liquid crystal host at a temperature at which the ferroelectric liquid crystal host is ferroelectric; wherein the side group liquid crystal polymer is polymerized and purified prior to contacting the ferrorelectric liquid crystal host and is not crosslinked; wherein the side group liquid crystal polymer has the structure (FX1):
wherein PX is a polymer; W is a spacer; and LC is a liquid crystal ferroelectric.
14. A ferroelectric liquid crystal composition, comprising:
a ferroelectric liquid crystal host; and between 0.01 and 5 wt % of a side group liquid crystal polymer, wherein the side group liquid crystal polymer is polymerized and purified prior to introduction into the ferroelectric liquid crystal host, is not crosslinked and has the structure (FX2):
wherein PX is
where n is independently an integer between 50 to 10000;
W is —(O) b —(CR 13 R 14 ) x —(O) b —FX—(O) b —(CR 15 R 16 ) y —(O) b —, where x and y are each independently integers from 0 to 20;
FX is a spacer selected from —O—, —C(═O)—,
where q is an integer from 0 to 10;
t is an integer from 1 to 10;
each b is independently 0 or 1; and
R 3 , R 4 , R 5 and R 6 are each independently selected from optionally substituted C 1 -C 6 alkyl, where the optional substituents are one or more halogens;
R 13 , R 14 , R 15 and R 16 are each independently hydrogen or halogen;
each L is independently selected from: —O—C(═O)—, —C(═O)—O—, —(CH 2 ) u —; and a single bond; where u is an integer from 1 to 10;
R 1 and R 2 are each independently:
where X 1 , X 2 , X 3 and X 4 are independently hydrogen, halogen, methoxy, C 1 -C 3 alkyl or —CN;
R 7 is each independently hydrogen, halogen, and —(O) v —(CH 2 ) p —CH 3 where p is an integer from 0 to 20 and v is 0 or 1;
R 30 and R 31 are each independently hydrogen or halogen, wherein the side group liquid crystal polymer is soluble in the ferroelectric liquid crystal host at a temperature at which the ferroelectric liquid crystal host is ferroelectric.
15. The ferroelectric liquid crystal composition of claim 2 , wherein the side group liquid crystal polymer has one of the structures:
where n is an integer from 50 to 10000 and each R 33 is independently an alkyl group having from 4 to 10 carbon atoms.
16. A ferroelectric liquid crystal composition, comprising:
a ferroelectric liquid crystal host; and between 0.01 and 5 wt % of a side group liquid crystal polymer, wherein the side group liquid crystal polymer is not crosslinked and has the structure (FX2):
wherein PX is
[—(Si(CH 2 )—O) n —], [—(CH 2 —CH(C(O)═O) n —], [—(CH 2 —C(CH 3 )(C(O)═O) n —], where n is independently an integer between 50 to 10000;
W is —(O) b —(CR 13 R 14 ) x —(O) b —FX—(O) b —(CR 15 R 16 ) y —(O) b —, where x and y are each independently integers from 0 to 20;
FX is a spacer selected from —O—, —C(═O)—,
where q is an integer from 0 to 10;
t is an integer from 1 to 10;
each b is independently 0 or 1; and
R 3 , R 4 , R 5 and R 6 are each independently selected from optionally substituted C 1 -C 6 alkyl, where the optional substituents are one or more halogens;
R 13 , R 14 , R 15 and R 16 are each independently hydrogen or halogen;
each L is independently selected from: —O—C(═O)—, —C(═O)—O—, —(CH 2 ) u —; and a single bond; where u is an integer from 1 to 10;
R 1 and R 2 are each independently:
where X 1 , X 2 , X 3 and X 4 are independently hydrogen, halogen, methoxy, C 1 -C 3 alkyl or —CN;
R 7 is each independently hydrogen, halogen, and —(O) v —(CH 2 ) p —CH 3 where p is an integer from 0 to 20 and v is 0 or 1;
R 30 and R 31 are each independently hydrogen or halogen, wherein the side group liquid crystal polymer is soluble in the ferroelectric liquid crystal host at a temperature at which the ferroelectric liquid crystal host is ferroelectric.