High activity catalyst for hydrosilylation reactions and methods of making the same

Patent metadata

Field	Value
Publication number	US-9993812-B2
Application number	US-201314373223-A
Country	US
Kind code	B2
Filing date	Mar 14, 2013
Priority date	Apr 17, 2012
Publication date	Jun 12, 2018
Grant date	Jun 12, 2018

Abstract

A heterogeneous catalyst comprising a metal-containing polymer matrix covalently bonded to a support material and a method of making and using such catalysts. The metal-containing polymer matrix comprises metal nano-particles encapsulated in a polymer matrix, e.g., a siloxane. In one aspect, the metal-containing polymer matrix can be bonded to the support material via a hydrophobic group attached to the support material. The catalyst can be recovered after being used in a metal catalyzed reaction and exhibit excellent catalytic activity upon reuse in subsequent reactions.

First claim

The invention claimed is:

1. A heterogeneous catalyst comprising a metal-containing siloxane polymer matrix covalently bonded to a support material,
wherein the support material is chosen from silicon, a sodium silicate, a borosilicate, a calcium aluminum silicate, clay, silica, calcium carbonate, barium carbonate, a metal oxide, and mixtures of two or more thereof;
wherein the support material comprises a functional group chosen from silanol, alkoxy, acetoxy, silazane, oximino-functional silyl group, hydroxyl, acyloxy, ketoximino, amine, aminoxy, alkylamide, hydrogen, an aliphatic olefinic group, aryl, hydrosulfide, or a combination of two or more thereof;
wherein the metal-containing siloxane polymer matrix comprises metal nanoparticles encapsulated in a siloxane polymer matrix, wherein the polymer matrix comprises a crosslinked or partially crosslinked network of hydrosiloxanes with a vinyl silicone compound, wherein the hydrosiloxanes are chosen from a silicon hydride-containing polyorganohydrosiloxane of the general formula:
M 1 a M 2 b D 1 c D 2 d T 1 e T 2 f Q J

wherein: M 1 =R 1 R 2 R 3 SiO 1/2 ; M 2 =R 4 R 5 R 6 SiO 1/2 ; D 1 =R 7 R 8 SiO 2/2 ; D 2 =R 9 R 10 SiO 2/2 ; T 1 =R 11 SiO 3/2 ; T 2 =R 12 SiO 3/2 ; Q=SiO 4/2 ; R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , and R 12 are aliphatic, aromatic or fluoro monovalent hydrocarbon having from 1 to 60 carbon atoms; at least one of R 9 or R 12 is hydrogen; and the subscript a, b, c, d, e, f, and j are zero or positive subject to the following limitations: 2≤a+b+c+d+e+f+j≤6000, and b+d+f>0;
wherein the covalent bond is formed between the functional group present on the support material and the siloxane polymer matrix.

2. The catalyst of claim 1 , wherein the metal nanoparticles are chosen from nanoparticles of aluminum, iron, silver, zinc, gold, copper, cobalt, nickel, platinum, manganese, rhodium, ruthenium, palladium, titanium, vanadium, chromium, molybdenum, cadmium, mercury, calcium, zirconium, iridium, cerium, oxides and sulfides of such metal, or combinations of two or more thereof.

3. The catalyst of 1 wherein the metal-containing polymer matrix has a ratio of polymer to metal of from about 1:1000 to about 100:1.

4. The catalyst of claim 1 , wherein the metal-containing polymer matrix has a weight ratio of polymer to metal of from about 1:1 to about 20:1.

5. The catalyst of claim 1 , wherein the metal-containing polymer matrix has a weight ratio of polymer to metal of from about 10:1 to about 20:1.

6. The catalyst of claim 1 , wherein the metal-containing polymer matrix has a weight ratio of polymer to metal of from about 12:1 to about 16:1.

7. The catalyst of claim 1 wherein the metal particles have a particle size of from about 1 to about 100 nanometers.

8. The catalyst of claim 1 wherein the metal loading ranges from about 0.05 to about 5 percent by weight of the support material.

9. The catalyst of claim 1 wherein the metal loading ranges from about 0.1 to about 1 percent by weight of the support material.

10. The catalyst of claim 1 , wherein the support material comprises a functional group chosen from —Si—CH═CH 2 , —Si—OH, —Si—(CH 2 ) n C≡CH, —Si—(CH 2 ) n —NH 2 , —Si—(CH 2 ) n —OH, —Si—(CH 2 ) n —SH, or a combination of two or more thereof, and n is 1-26.

11. The catalyst of claim 1 wherein the metal-containing polymer matrix is covalently bonded to the support material via a hydrophobic functional group attached to the support material.

12. The catalyst of claim 11 wherein the hydrophobic functional group is chosen from a silazane-containing functional group.

13. A method of synthesizing supported nanoparticle catalysts, the method comprising:
(a) forming a metal-containing polymer matrix comprising metal nanoparticles by forming a colloidal suspension of metal nano-particles by reacting metal complexes with a silicon hydride-containing polyorganohydrosiloxane solution to form a colloidal suspension of metal nano-particles and subsequently reacting the suspension to form a polymer matrix and encapsulate the metal nano-particles in a siloxane matrix, wherein the polymer matrix comprises a crosslinked or partially crosslinked network of hydrosiloxanes with a vinyl silicone compound, and the hydrosiloxanes are chosen from a silicon hydride-containing polyorganohydrosiloxane of the general formula:
M 1 a M 2 b D 1 c D 2 d T 1 e T 2 f Q J

wherein: M 1 =R 1 R 2 R 3 SiO 1/2 ; M 2 =R 4 R 5 R 6 SiO 1/2 ; D 1 =R 7 R 8 SiO 2/2 ; D 2 =R 9 R 10 SiO 2/2 ; T 1 =R 11 SiO 3/2 ; T 2 =R 12 SiO 3/2 ; Q=SiO 4/2 ; R 1 , R 2 , R 3 ,R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , R 10 , R 11 , and R 12 are aliphatic, aromatic or fluoro monovalent hydrocarbon having from 1 to 60 carbon atoms; at least one of R 9 or R 12 is hydrogen; and the subscript a, b, c, d, e, f, and j are zero or positive subject to the following limitations: 2≤a+b+c+d+e+f+j≤6000, and b+d+f>0; and
(b) attaching the metal-containing polymer matrix to a support material via covalent chemical bonds, wherein the support material is chosen from silicon, a sodium silicate, a borosilicate, a calcium aluminum silicate, clay, silica, metal oxide, and mixtures of two or more thereof; and wherein the support material comprises a functional group chosen from silanol, alkoxy, acetoxy, silazane, oximino-functional silyl group, hydroxyl, acyloxy, ketoximino, amine, aminoxy, alkylamide, hydrogen, an aliphatic olefinic group, aryl, hydrosulfide, or a combination of two or more thereof.

14. The method of claim 13 wherein the reacting of the metal complexes with a silicon hydride-containing polyorganohydrosiloxane solution in solvent is under nitrogen atmosphere.

15. The method of claim 14 , wherein the metal complex is selected from a metal salt chosen from PtCl 2 , H 2 PtCl 6 , Pt 2 (dba) 3 , Pt 2 (dvs) 3 , Pt(OAc) 2 Pt(acac) 2 , Na 2 PtCl 6 , K 2 PtCl 6 , platinum carbonate, platinum nitrate, 1,5-cycooctadienedimethylplatinum(II), platinum perchlorate, amine complexes of the platinum ammonium hexachloropalladate(IV), palladium(II) chloride, AuCl 3 , Au 2 O 3 , NaAuO 2 , AgCl, AgNO 3 , CuSO 4 , CuO, Cu(NO 3 ) 2 , CuCl 2 , Ru 2 O 3 , RuCl 2 , FeCl 2 .6H 2 O, ZnCl 2 , CoCl 2 .6H 2 O, NiCl 2 .6H 2 O, MnCl 2 .4H 2 O, TiCl 4 , vanadium chloride, cadmium chloride, calcium chloride, zirconium tetrachloride, mercuric chloride complexes, or a combination of two or more thereof.

16. The method of claim 14 , wherein encapsulating the metal nano-particles in the siloxane matrix comprises exposing the colloidal suspension to the presence of oxygen for a time period of from about 10 to about 30 minutes.

17. The method of claim 14 further comprising an optional step of removing at least about 50% of the solvent from the colloidal solution.

18. The method claim 13 , wherein the ratio of polymer to metal complex ranges from about 0.001 to about 100.

19. The catalyst of claim 1 , wherein the molecular weight of the polysiloxanes range from 100 to 50000, and the Si—H content of the polysiloxanes ranges from 0.001 to 99 mole percent.

20. The method claim 13 , wherein the nanoparticles are chosen from at least one of aluminum, iron, silver, zinc, gold, copper, cobalt, nickel, platinum, manganese, rhodium, ruthenium, palladium, titanium, vanadium, chromium, molybdenum, cadmium, mercury, calcium, zirconium, iridium, cerium, oxides and sulfides thereof.

21. The method of claim 13 , wherein the step of (b) is carried out at a temperature between about 5 degre

Assignees

• Momentive Performance Mat Inc
• Momentive Pereformance Mat Inc

Inventors

• Komati Srinivas
• Khare Vivek
• Lewis Kenrick
• Sarkar Alok
• Srikanth Abirami
• Roy Aroop Kumar

Classifications

• C07C2521/08

  Silica · CPC title

• C07C2531/06

  containing polymers · CPC title

• C07C2523/42

  Platinum · CPC title

• C07C5/09

  to carbon-to-carbon double bonds · CPC title

• B01J2231/4261

  Heck-type, i.e. RY + C=C, in which R is aryl · CPC title