Method of making a fiber optical cable assembly

• US 8,406,589 B2
• Filed: 01/26/2010
• Issued: 03/26/2013
• Est. Priority Date: 01/26/2010
• Status: Expired due to Fees

• Current Assignee: DuPont Safety & Construction, Inc. (DuPont de Nemours, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Amma, Achim
• Primary Examiner(s): Le, Uyen Chau N
• Assistant Examiner(s): MOONEY, MICHAEL P
• Application Number:
  US12/693,500
• Publication Number:
  US 20110182553A1
• Time in Patent Office: 1,155 Days
• Field of Search: 385101-104, 385/113, 385/100, 428/364, 428/372, 428/373, 428/375, 428/379, 428/383, 428/389, 428/395, 428/378, 264/1.28
• US Class Current: 385/100
• 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 15/59 Polyamides; Polyimides
• CPC Class Codes: D06M 2101/36 Aromatic polyamides
• CPC Class Codes: G02B 6/4432 with fibre reinforcements
• CPC Class Codes: G02B 6/44384 the means comprising water blocking or hydrophobic materials G02B6/4439, G02B6/4479 take precedence
• CPC Class Codes: Y10T 428/2933 Coated or with bond, impregnation or core
• CPC Class Codes: Y10T 428/2938 Coating on discrete and individual rods, strands or filaments

Abstract

A process for forming a fiber optical cable assembly comprises the steps of (a) subjecting a first high tenacity reinforcement yarn such as para-aramid that is coated with a water-impermeable thermally reversible cross-linked polymeric coating to a temperature of from 45 to 200 ° C. for sufficient time to convert the protective coating via bond cleavage into a water-swellable super absorbent polymer, (b) combining one or more of the first reinforcement yarns from step (a) with one or more optical glass fiber transmission media and (c) applying a protective sleeve over at least one assembly of step (b).

Claims

1. A process for forming a fiber optical cable assembly comprising the steps of:

(a) subjecting a first reinforcement yarn having a linear density of from 150 to 12000 dtex, a tenacity of from 10 to 65 g/dtex, a modulus of from 150 to 2700 g/dtex, and an elongation to break of from 1 to 8 percent coated with a water-impermeable thermally reversible cross-linked polymeric precursor coating to a temperature of from 45 to 200°

C. for sufficient time to convert the protective precursor coating via bond cleavage into a water-swellable super absorbent polymer, (b) combining one or more of the first reinforcement yarns from step (a) with one or more optical glass fiber transmission media and (c) applying a protective sleeve over at least one assembly of step (b),

wherein the precursor coating is a cross-linked polymer comprising reversible covalent bonds capable of bond cleavage under heat.

2. The process of claim 1, wherein at least one second reinforcement yarn may optionally be combined with the first reinforcement yarns and glass fiber transmission media in step (b).

3. The process of claim 1, wherein the polymer of the first reinforcement yarn is selected from the group consisting of p-aramid, polybenzazole, polypyridazole or mixtures thereof.

4. The process of claim 1, wherein the thermally reversible cross-linkers of the thermally reversible coating are present in an amount of from 0.001% to 0.5% weight percent based on the total weight of first reinforcement yarn plus coating.

5. The process of claim 1, wherein the thermally reversible cross-linked coating is present in the amount of from 0.1% to 10% weight percent based on the total weight of the first reinforcement yarn plus coating.

6. The process of claim 3, wherein the p-aramid is poly(paraphenylene terephthalamide).

7. A fiber optic cable made by the process of claim 1.

8. The process of claim 1, wherein the coating comprises a blocked isocyanate, a Diels-Alder reaction product, an azo compound or mixtures thereof.