Polymers, their preparation and uses
A polymer containing an optionally substituted repeat unit of formula (I) wherein each R is the same or different and represents H or an electron withdrawing group, and each R 1 is the same or different and represents a substituent.
1. A composition comprising:
a polymer comprising an optionally substituted first repeat unit of formula (VII):
wherein each R 2 is the same or different and represents a substituent; the R 2 groups may be linked to form a ring; bond (a) is bound to the 3-position of the repeat unit of formula (VII); and bond (b) is bound to the 6-position of the repeat unit of formula (VII); and,
a phosphorescent dopant.
2. A composition according to claim 1 , wherein at least one R 2 is a solubilizing group.
3. A composition according to claim 1 , wherein each R 2 is the same or different and is selected from the group consisting of optionally substituted C 1-20 alkyl, optionally substituted C 1-20 alkoxy, optionally substituted aryl, and optionally substituted heteroaryl.
4. A composition according to claim 3 , wherein each R 2 is a C 4 -C 10 alkyl.
5. A composition according to claim 1 wherein the polymer comprises an optionally substituted aryl or heteroaryl second repeat unit.
6. An optionally substituted monomer of formula (VIII):
wherein each R 2 is the same or different and represents a substituent; each X independently represents a polymerizable group; bond (a) is bound to the 3-position of the repeat unit of formula (VII); and bond (b) is bound to the 6-position of the repeat unit of formula (VII).
7. A monomer according to claim 6 , wherein each R 2 is the same or different and is selected from the group consisting of optionally substituted C 1-20 alkyl, optionally substituted C 1-20 alkoxy, optionally substituted aryl, and optionally substituted heteroaryl.
8. A monomer according to claim 6 , wherein each R 2 is a C 4 -C 10 alkyl.
9. An electroluminescent device comprising an anode, a cathode and an electroluminescent layer located between the anode and cathode wherein the electroluminescent layer comprises a polymeric host material comprising an optionally substituted first repeat unit of formula (VII) and a phosphorescent dopant:
wherein each R 2 is the same or different and represents a substituent; the R 2 groups may be linked to form a ring; bond (a) is bound to the 3-position of the repeat unit of formula (VII); and bond (b) is bound to the 6-position of the repeat unit of formula (VII).