Defoaming formulations containing organopolysiloxanes

Patent metadata

Field	Value
Publication number	US-11925883-B2
Application number	US-201817292584-A
Country	US
Kind code	B2
Filing date	Nov 28, 2018
Priority date	Nov 28, 2018
Publication date	Mar 12, 2024
Grant date	Mar 12, 2024

Abstract

Defoamer formulations with rapid knockdown and extended performance contain specific polyorganosiloxanes having alkylene linkages between siloxy groups, silicone resins, fillers, a polyoxyethylene surfactant, and an organic or inorganic acid.

First claim

The invention claimed is:

1. A defoamer formulation, comprising:
(1) organopolysiloxane(s) containing per molecule

at least one structural unit of formula
O 1/2 R 2 Si—Y—SiRO 2/2   (I)

and at least 2 units of formula
R 1 R 2 SiO 1/2   (II)

and units of formula
R 2 SiO 2/2   (III),

wherein
R each is identical or different and represents a monovalent SiC-bonded hydrocarbon radical having 1 to 30 carbon atoms which optionally contains one or more nonadjacent oxygen atoms and which is free from aliphatic carbon-carbon multiple bonds, and
R 1 is R or an alkenyl radical having 2 to 30 carbon atoms, wherein at least one alkenyl radical per molecule is present,
Y is a divalent hydrocarbon radical having 2 to 30 carbon atoms, with the proviso that the organopolysiloxane contains a structural element of formula
R 2 Y 2 SiO—(SiR 2 O) x1 —SiRY 1 O—(SiR 2 O) x2 —SiR 2 R 1   (IV),

wherein
R and R 1 are as defined above,
Y 1 represents a divalent hydrocarbon radical having 2 to 30 carbon atoms which is bonded to a group having the formula SiR 2 O 1/2 ,
Y 2 represents a divalent hydrocarbon radical having 2 to 30 carbon atoms which is bonded to a group having the formula SiRO 2/2 , and
x 1 and x 2 are 0 or an integer,
with the proviso that the sum of x 1 +x 2 is x,
wherein x is on average more than 5, and less than 100,
(2) fillers,
(3) organopolysiloxane resin(s) composed of units of formula
R 2 e (R 3 O) f SiO (4-e-f)/2   (V),

wherein
R 2 each is identical or different and represents a hydrogen atom or a monovalent, optionally substituted, SiC-bonded hydrocarbon radical having 1 to 30 carbon atoms,
R 3 each is identical or different and represents a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical having 1 to 4 carbon atoms,
e is 0, 1, 2, or 3 and
f is 0, 1, 2, or 3,
with the proviso that the sum of e+f is not more than 3 and that the sum of e+f is 2 in less than 50% of all units of formula (V) in the organopolysiloxane resin,
(4) polyethylene oxide-derived surfactants, and
(5) inorganic or organic acids.

2. The defoamer formulation of claim 1 , wherein Y and Y 1 and Y 2 are each a radical of formula —CH 2 CH 2 —.

3. The defoamer formulation of claim 1 , wherein the organopolysiloxane(s) (1) are produced by reacting
(A) oligomeric or polymeric organosilicon compounds containing units of formula
R 1 R 2 SiO 1/2   (II),

units of formula
R 2 SiO 2/2   (III),

and units of formula
HRSiO 2/2   (VIII)

with the provisos that
at least one alkenyl radical R 1 per molecule is present,
the sum of the units HRSiO 2/2 and R 1 R 2 SiO 1/2 is on average greater than 2.0,
and the number of alkenyl radicals R 1 is on average greater than the number of Si-bonded hydrogen atoms
and optionally
(B) oligomeric or polymeric organosilicon compounds containing units of formula
R 7 R 2 SiO 1/2 (IX) and

units of formula
R 2 SiO 2/2   (III),

wherein
R is as defined in claim 1 , and
R 7 is an alkenyl radical having 2 to 30 carbon atoms,
in the presence of
(C) catalysts which promote the addition of Si-bonded hydrogen onto aliphatic double bonds,

wherein the ratio of aliphatic double bond in the components (A) and optionally (B) to Si-bonded hydrogen in the component (A) is 1.2 to 10.

4. The defoamer formulation of claim 1 , wherein the organopolysiloxane(s) (1) are produced by reacting
(A) oligomeric or polymeric organosilicon compounds containing units of formula
R 1 R 2 SiO 1/2   (II),

units of formula
R 2 SiO 2/2   (III),

and units of formula
HRSiO 2/2   (VIII)

with the provisos that
at least one alkenyl radical R 1 per molecule is present,
the sum of the units HRSiO 2/2 and R 1 R 2 SiO 1/2 is on average greater than 2.0,
and the number of alkenyl radicals R 1 is on average greater than the number of Si-bonded hydrogen atoms
and optionally
(B) oligomeric or polymeric organosilicon compounds containing units of formula
R 7 R 2 SiO 1/2 (IX) and

units of formula
R 2 SiO 2/2   (III),

wherein
R is as defined in claim 1 , and
R 7 is an alkenyl radical having 2 to 30 carbon atoms,
in the presence of
(C) catalysts which promote the addition of Si-bonded hydrogen onto aliphatic double bonds,

wherein the ratio of aliphatic double bond in the components (A) and optionally (B) to Si-bonded hydrogen in the component (A) is 1.5 to 5.

5. The defoamer formulation of claim 3 , wherein the organosilicon compound(s) (A) have the formula
R 1 R 2 SiO—(SiR 2 O) x —(HSiRO) y —SiR 2 R 1   (X),

wherein
R, R 1 and x are as defined in claim 1 ,
and y is on average at least 0.5, and on average at most 1.5,
with the provisos that at least one alkenyl radical R 1 per molecule is present,
the sum of the units HRSiO 2/2 and R 1 R 2 SiO 1/2 is on average greater than 2.0,
and the number of alkenyl radicals R 1 is on average greater than the number of Si-bonded hydrogen atoms.

6. The defoamer formulation of claim 3 , wherein the organosilicon compound(s) (B) have the formula
R 7 R 2 SiO—(SiR 2 O) z —O—SiR 2 R 7   (XI),

wherein
z is on average more than 5, and less than 1000.

7. The defoamer formulation of claim 1 , wherein the polyethylene oxide-derived surfactants (4) used are alkyl polyglycol ethers of the formula
R 4 —[O—CH 2 —CH 2 ] n —OH  (VI),

in which
R 4 is a monovalent hydrocarbon radical having 1 to 30 carbon atoms, and
n has integer values between 1 and 100.

8. The defoamer formulation of claim 1 , wherein one acid (5) is phosphoric acid.

9. The defoamer formulation of claim 1 , further comprising:
(6) polyorganosiloxane(s) of formula
R 5 R 2 SiO(SiR 2 O) m SiR 2 R 5   (VIIa) or

wherein
R each is identical or different and is as defined above,
R 5 each is identical or different and may be R or —OR 6 , wherein
R 6 represents a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical having 1 to 25 carbon atoms,
m is an integer,
n is an integer,
wherein the polyorganosiloxanes may also contain small proportions of branchings, preferably T units (R 5 SiO 3 /2) and Q units (SiO 2 ),
optionally
(7) water-insoluble organic compounds,
optionally
(8) polyether-modified polysiloxanes which may be linear or branched and contain at least one polyether group and optionally
(9) alkaline or acidic catalysts or their reaction products with the components (1) to (8).

10. The defoamer formulation of claim 1 , further comprising:
(6) polyorganosiloxane(s) of formula
R 5 R 2 SiO(SiR 2 O) m SiR 2 R 5   (VIIa)

wherein
R each is identical or different and is as defined above,
R 5 each is identical or different and may be R or —OR 6 , wherein
R 6 represents a hydrogen atom or a monovalent, optionally substituted hydrocarbon radical having 1 to 25 carbon atoms,
m is 1 to 2500,
n is 2 to 20, respectively
wherein the polyorganosiloxanes may also contain small proportions of branchings, preferably T units (R 5 SiO 3/2 ) and Q units (SiO 2 ),

Assignees

• Wacker Chemie Ag

Inventors

• Grandl Markus
• Deckert Christoph
• Hoelzlwimmer Elisabeth
• Sage Corinna
• Wimmer Josef

Classifications

• B01D19/0409 Primary

  compounds containing Si-atoms · CPC title

• C11D1/72

  Ethers of polyoxyalkylene glycols · CPC title

• C11D3/0026

  Low foaming or foam regulating compositions · CPC title

• C11D3/373

  containing silicones · CPC title

• D21H21/12

  Defoamers · CPC title