Superabsorbent-coated aramid yarn and a process for manufacturing such a yarn

• US 5,264,251 A
• Filed: 10/23/1991
• Issued: 11/23/1993
• Est. Priority Date: 10/26/1990
• Status: Expired due to Term

• Current Assignee: AKZO NV (Nouryon BV)
• Original Assignee: AKZO NV (Nouryon BV)
• Inventors: Willemsen, Stephanus, Geursen, Herman J.
• Primary Examiner(s): Beck, Shrive
• Assistant Examiner(s): Dudash, Diana L.
• Application Number:
  US07/781,784
• Time in Patent Office: 762 Days
• Field of Search: 427/389.9, 428/395, 174/23 C, 174/107
• US Class Current: 427/389.9
• CPC Class Codes: D02G 3/447 Yarns or threads for specific use in general industrial applications, e.g. as filters or reinforcement
• CPC Class Codes: D06M 15/263 of unsaturated carboxylic acids; Salts or esters thereof
• CPC Class Codes: D06M 15/285 of unsaturated carboxylic acid amides or imides
• CPC Class Codes: D06M 2101/36 Aromatic polyamides
• CPC Class Codes: D06M 2200/00 Functionality of the treatment composition and/or properties imparted to the textile material
• CPC Class Codes: D10B 2331/021 aromatic polyamides, e.g. aramides
• CPC Class Codes: G02B 6/4434 Central member to take up tensile loads
• CPC Class Codes: G02B 6/44384 the means comprising water blocking or hydrophobic materials G02B6/4439, G02B6/4479 take precedence
• CPC Class Codes: Y10T 428/256 Heavy metal or aluminum or compound thereof
• CPC Class Codes: Y10T 428/2969 Polyamide, polyimide or polyester
• CPC Class Codes: Y10T 428/31797 Next to addition polymer from unsaturated monomers

Abstract

An aramid yarn, preferably poly(p-phenylene terephthalamide), is coated with a water swellable superabsorbent material. The swelling value of the yarn is at least 60. The superabsorbent provides water blocking capability to the yarn, so that it is suitable for use as a strength member, for example, in water tight optical communication cables. The yarn is made by successively treating an aramid yarn with a water-in-oil emulsion, a superabsorbent material being present in the water phase of the emulsion, and removing the liquid components from the treated yarn by evaporation.

Claims

1. A process for the manufacture of an aramid yarn provided with a superabsorbent material which comprises providing a layer of a water-in-oil emulsion containing a superabsorbent in its aqueous phase on the aramid yarn surface and removing at least a portion of emulsion'"'"'s liquid ingredients from the year by evaporation to give an amount of superabsorbent on the yarn of about 0.3 wt % to 10 wt %, based on the weight of the yarn.

2. A process according to claim 1 wherein the aramid yarn which is treated comprises poly(p-phenylene terephthalamide).

3. A process according to claim 1 wherein the water-in-oil emulsion contains from about 2 to about 50 wt. % of the superabsorbent material.

4. A process according to claim 1 wherein the superabsorbent material is a derivative of polyacrylic acid.

5. A process according to claim 1 wherein the water-in-oil emulsion contains from about 20 to about 80 wt. %, calculated on the undiluted emulsion, of a stabilizer having an HLB value of less than about 5.

6. A process as claimed in claim 1 wherein the coated yarn comprises from about 0.5 wt % to about 5 wt % of the superabsorbent material.

7. A process as claimed in claim 1 wherein the yarn comprises filaments of practically unlimited length.