1. A catalyst obtained from
a) a chromium compound CrX3 and the at least equimolar amount, based on the chromium compound CrX3, of a ligand L or from an existing chromium complex CrX3L, in which the groups X are, independently of one another, abstractable counterions and L is a 1,3,5-triazacyclohexane of the formula I
\u2003where the groups R1 to R9 are, independently of one another: hydrogen or organosilicon or substituted or unsubstituted carboorganic groups having from 1 to 30 carbon atoms, where two geminal or vicinal radicals R1 to R9 may also be joined to form a five- or six-membered ring, and
b) at least one activating additive selected from the group consisting of (i) and (ii) wherein:
i) is a combination of an unsubstituted or substituted five-membered aromatic N-heterocycle and at least one aluminum alkyl, wherein some of the alkyl groups of the aluminum alkyl are optionally replaced by halogen andor alkoxy, and
ii) is an alkylalumoxane.
2. The catalyst defined in claim 1, wherein the groups R1, R2 and R3 in the 1,3,5-triazacyclohexane I are, independently of one another, substituted or unsubstituted C1-C12-al-kyl, C6-C15-aryl or C7-Cg-arylalkyl.
3. The catalyst defined in claim 1, wherein the groups R1, R2 and R3 in the 1,3,5-triazacyclohexane I are, independently of one another, substituted or unsubstituted C1-C12-al-kyl or C7-C8-arylalkyl.
4. (1,3,5-Tris(2-n-propylheptyl)-1,3,5-triazacyclohexane) CrCl3.
5. (1,3,5-Tris(2-ethylhexyl)-1,3,5-triazacyclohexane) CrCl3.
6. A process for preparing oligomers having up to 30 carbon atoms by reaction of an olefin or a mixture of olefins at from 0 to 150\xb0 C. and pressures of from 1 to 200 bar in the presence of the catalyst defined in claim 1.
7. The catalyst defined in claim 1, wherein the groups R4, R5, R6, R7, R8 and R9 in the 1,3,5-triazacyclohexane I are, independently of one another, hydrogen or methyl.
8. A process as claimed in claim 6, wherein the olefin or mixture of olefins is selected from straight-chain and branched \u03b1-olefins having from 2 to 4 carbon atoms.
9. A process as claimed in claim 6, wherein the olefin or mixture of olefins is selected from 1-butene and 1-butene in mixture with its isomers.
10. A process as claimed in claim 6, wherein the olefin or mixture of olefins is employed in form of a raffinate comprising 1-butene in mixture with its isomers.
11. A process as claimed in claim 6, wherein the olefin is ethene.
12. A process as claimed in claim 6, wherein the catalyst is obtained from
a) a chromium compound CrX3 and the at least equimolar amount, based on the chromium compound CrX3, of a ligand L or from an existing chromium complex CrX3L, in which the groups X are, independently of one another, abstractable counterions and L is a 1,3,5-triazacyclohexane of the formula I
\u2003where the groups R1 to R9 are, independently of one another:
hydrogen or organosilicon or substituted or unsubstituted carboorganic groups having from 1 to 30 carbon atoms, where two geminal or vicinal radicals R1 to R9 may also be joined to form a five- or six-membered ring, and R1, R2 and R3 in part or in whole, and independently of one another, are a group which carries a substituent attached via a carbon atom, in the p position relative to the nitrogen atom of the 1,3,5-triazacyclohexane ring, and
b) the alkylalumoxane.
13. A process as claimed in claim 12, wherein the olefin is ethene.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A controlled-release molecular iodine system comprising:
a mixture of nanoparticles particles that have both epithelial cell-binding molecules and lymphocyte-binding molecules attached to their surfaces; wherein,
half of these particles contain a pH buffer, and half contain iodide and iodate salts.
2. The system of claim 1 wherein said half containing a pH buffer contains a pH buffer that controls pH to between around pH 3.5 to around pH 4.5.
3. The system of claim 2 wherein said pH buffer contains acetic acid and sodium acetate or citric acid and sodium citrate.
4. The system of claim 1 wherein said particles are biodegradable.
5. The system of claim 1 wherein said epithelial cell binding molecules are actin or fibronectin.
6. The system of claim 1 wherein said lymphocyte cell binding molecules include hyaluronic acid, chondroitin-4-sulfate, chondroitin-6-sulfate or heparin.
7. The system of claim 1 wherein said iodide salt is potassium or sodium iodide, and said iodate salt is potassium or sodium iodate.
8. The system of claim 1 wherein said nanoparticles have diameters of around 50-100 \u03bcm.
9. A controlled-release molecular iodine system comprising:
a mixture of two populations of nanoparticles particles where particles of a first population has epithelial cell-binding molecules attached to their surfaces and particles of a second population has lymphocyte-binding molecules attached to their surfaces; wherein,
half of all of these particles contain a pH buffer, and half contain iodide and iodate salts.
10. The system of claim 9 wherein said half containing a pH buffer contains a pH buffer that controls pH to between around pH 3.5 to around pH 4.5.
11. The system of claim 10 wherein said pH buffer contains acetic acid and sodium acetate or citric acid and sodium citrate.
12. The system of claim 9 wherein said particles are biodegradable.
13. The system of claim 9 wherein said epithelial cell binding molecules are actin or fibronectin.
14. The system of claim 9 wherein said lymphocyte cell binding molecules include hyaluronic acid, chondroitin-4-sulfate, chondroitin-6-sulfate or heparin.
15. The system of claim 9 wherein said iodide salt is potassium or sodium iodide, and said iodate salt is potassium or sodium iodate.
16. The system of claim 9 wherein said nanoparticles have diameters of around 50-100 \u03bcm.
17. A method of controlled release molecular iodine for body cavities comprising:
attaching molecules onto surfaces of a population of particles including epithelial cell-binding molecules and lymphocyte-binding molecules;
causing half said particles to contain a pH buffer and half said particles to contain iodide and iodate salts.
18. The method of claim 17 wherein said particles are between around 50 to 100 \u03bcm.
19. The method of claim 17 wherein said buffer controls pH to between around pH 3.5 to around pH 4.5.