Composite membrane of a hydrophilic asymmetric membrane coated with an organosiloxane block copolymer

• US 5,296,144 A
• Filed: 01/02/1992
• Issued: 03/22/1994
• Est. Priority Date: 01/02/1992
• Status: Expired due to Fees

• Current Assignee: World Trade Corporation
• Original Assignee: World Trade Corporation
• Inventors: Fedotov, Alexander F., Strukova, Vera V., Mikhailovich, Victor, Sternina, Larisa F., Shkolnik, Mark I.
• Primary Examiner(s): SPEAR JR, FRANK
• Application Number:
  US07/816,187
• Time in Patent Office: 810 Days
• Field of Search: 210/640, 210/490, 210/500.27, 210/500.28, 427/246, 525/489, 424/447
• US Class Current: 210/490
• CPC Class Codes: B01D 69/125 In situ manufacturing by polymerisation, polycondensation, cross-linking or chemical reaction
• CPC Class Codes: B01D 71/54 Polyureas; Polyurethanes
• CPC Class Codes: B01D 71/70 Polymers having silicon in the main chain, with or without sulfur, nitrogen, oxygen or carbon only
• CPC Class Codes: B01D 71/702 Polysilsesquioxanes or combination of silica with bridging organosilane groups
• CPC Class Codes: B01D 71/80 Block polymers
• CPC Class Codes: C08G 18/6705 Unsaturated polymers not provided for in the groups C08G18/671, C08G18/6795, C08G18/68 or C08G18/69

Abstract

An organosiloxane block copolymer having the formula depicted (I) depicted below: ##STR1## wherein: m has a value of 8.0-18.0;

n has a value of 1.0-5.0;

x has a value of about 0.2 to about 0.7;

y has a value of 1 minus the value of x;

R is ##STR2## R¹ ##STR3## R² is a C₁ -C₅ lower alkylene group; V is a vinyl group; and

Me is a methyl group.

Preparation of the organosiloxane block copolymer of the above formula (I) by polymerizing α,w-bis(oxymethyl)polydimethyl-methylvinylsiloxane, and diphenylmethanediisocyanate, and di(oxyethyl)m-toluidine in the presence of a solvent and a catalyst. A composite membrane, which may be used in a pervaporation process, comprising a hydrophilic asymmetric membrane coated with a mixture of an organosiloxane block copolymer, a linking reagent and a catalytically effective amount of a hydrosilylation catalyst.

Claims

1. A composite membrane comprising a hydrophilic asymmetric membrane coated with a mixture of:

(a) a poly(methylvinyl)siloxane urethane block copolymer having the structural formula (I) depicted below;

##STR31## wherein;

m has a value of 8.0-18.0;

n has a value of 1.0-5.0;

x has a value of about 0.2 to about 0.7;

y has a value of 1 minus the value of x;

R is ##STR32## R¹ is ##STR33## R² is a C₁ -C₅ lower alkylene group;

v is a vinyl group; and

Me is a methyl group;

(b) a linking reagent; and

(c) a catalytically effective amount of a hydrosilylation catalyst.

2. A composite membrane according to claim 1, wherein m has a value of 14.0;

n has a value of 1.0;

x has a value of about 0.224; and

R² is a C₁ lower alkylene having the formula --CH₂ --.

3. A composite membrane according to claim 1 wherein m has a value of 13.0;

n has a value of 2.0;

x has a value of 0.369; and

R² is a C₃ lower alkylene having the formula --(CH₂)₃ --.

4. The composite membrane according to claim 1, wherein the hydrophilic asymmetric membrane is selected from the group consisting of a cellulose acetate, polyamide, polyamide-imide, and polyamidic-polysulphone.

5. A composite membrane comprising a hydrophilic asymmetric membrane coated with a mixture of (a) an organosiloxane block copolymer having the general formula

View Dependent Claims (6, 7, 8, 9, 10, 11, 12)

6. The composite membrane according to claim 5, wherein B is an organic polymer selected from the group consisting of a polycarbonate, a polysulphone, a polyurea, a polyether and a polyimide.

7. The composite membrane according to claim 6, wherein A is the organosiloxane block copolymer having the structural formula depicted below:

##STR34## where;

m has a value of 8.0-18.0;

n has a value of 1.0-5.0;

Me is a methyl group of hydrogen;

V is at least one vinyl group with the remaining compounds selected from the group consisting of vinyl and Me; and

1has a value of 1-3.

8. The composite membrane according to claim 6, wherein the polycarbonate has the structural formula ##STR35## where k has a value of 7-12 and each R³ is selected from the group consisting of a C₁ -C₅ lower alkylene or where the R³ groups in combination are ##STR36## wherein the polysulphone has the structural formula ##STR37## where k has a value of 7-12 and each R³ is selected from the group consisting of a C₁ -C₅ lower alkylene or where the R³ groups in combination are ##STR38## wherein the polyurea has the structural formula ##STR39## wherein the polyether has the structural formula ##STR40## where 1 has a value of 1-3 and R³ is a compound selected from the group consisting of a C₁ -C₅ lower alkylene;

and wherein the polyimide has the structural formula ##STR41## where k has a value of 7-12.

9. The composite membrane according to claim 8, wherein A is the organosiloxane block copolymer having the structural formula depicted below:

##STR42## where;

m has a value of 8.0-18.0;

n has a value of 1.0-5.0;

Me is a methyl group or hydrogen;

V is at least one vinyl group - with the remaining compounds selected from the group consisting of vinyl and Me; and

1has a value of 1-3.

10. The composite membrane according to claim 5, wherein the linking reagent is an oligohydride ethylsiloxane.

11. The composite membrane according to claim 5, wherein the hydrosilylation catalyst is selected from the group consisting of platinum (IV) complexes, olefin platinum complexes and chloroplatinic acid.

12. The composite membrane according to claim 5, wherein the hydrophilic asymmetric membrane is selected from the group consisting of a cellulose acetate, polyamide, polyamide-imide, and polyamidic-polysulphone.