Membrane sealing techniques using thermoplastic polymers

• US 5,556,591 A
• Filed: 08/19/1994
• Issued: 09/17/1996
• Est. Priority Date: 01/21/1992
• Status: Expired due to Fees

• Current Assignee: Millipore SAS (Merck & Co., Inc.)
• Original Assignee: Millipore SAS (Merck & Co., Inc.)
• Inventors: Jallerat, Eric, Lemonnier, Jean
• Primary Examiner(s): Timm, Catherine
• Application Number:
  US08/292,982
• Time in Patent Office: 760 Days
• Field of Search: 264/510, 264/511, 264/516, 264/571, 264/573, 264/261, 264/279, 264/555, 264/562, 264/263, 210/321.8, 210/321.89, 210/450, 210/500.23, 156/285
• US Class Current: 264/516
• CPC Class Codes: B01D 2313/44 Cartridge types
• CPC Class Codes: B01D 63/0233 forming the bundle
• CPC Class Codes: B01D 63/0241 being U-shaped
• CPC Class Codes: B01D 63/04 comprising multiple hollow fibre assemblies
• CPC Class Codes: C12G 1/064 using enclosed yeast

Abstract

A process for potting hollow fibers within a body is disclosed wherein a bundle of hollow fibers is formed within a hollowed portion of the body such that the fibers are substantially aligned and uniformly spaced. A molten thermoplastic composition is dispensed into the body at a contact temperature below the melting point of the hollow fibers. The bundle and the body are both at a temperature which is sufficiently low enough to cause solidification of the molten composition substantially upon contact with the bundle. A pressure differential is applied to the body to assist the flow of the thermoplastic composition around each of the hollow fiber elements such that the bundle and the interior of the hollowed portion of the body are encapsulated by the thermoplastic composition thereby assuring reliable sealing between the hollow fiber elements and the interior of the hollowed portion of the body.

Claims

1. A process for potting hollow fibers within a body, comprising the steps of:

a. forming a bundle of hollow fibers within a hollowed portion of said body, said fibers being substantially aligned longitudinally and uniformly spaced within said hollowed portion;

b. dispensing along the longitudinal axis of said bundle a molten thermoplastic composition into said hollowed portion at a contact temperature which is below the melting point of the hollow fibers but which is sufficient to lower the viscosity of said molten composition to allow said composition to flow around all fibers within the bundle;

c. applying a pressure differential to the body to assist the flow of the thermoplastic composition between each of the hollow fiber elements and the interior of the body;

d. said bundle being at a temperature low enough to cause solidification of said molten thermoplastic composition substantially upon contact with said bundle, whereby a solid thermoplastic block is formed encapsulating said bundle within said hollowed portion to create an impervious seal around every hollow fiber in said bundle and the interior of said body.

2. The process of claim 1 wherein said body includes an annular ring for accepting the bundle of hollow fibers, the ring being integral with the body and extending at an angle relative to the inside wall of said hollowed portion of the body.

3. The process of claim 1 wherein the thermoplastic composition belongs to the family of ethylene-vinyl acetate copolymers, with viscosity and adhesive modifying additives.

4. The process of claim 1 wherein the hollow fibers are made from polyethersulfone (PES).

5. The process of claim 4 wherein the contact temperature of the thermoplastic composition is between 160°

and 170°

C.

6. The process of claim 1 wherein the pressure differential is achieved by applying a vacuum to the bundle.