Foam for optical fiber cable, composition, and method of manufacturing

Patent metadata

Field	Value
Publication number	US-11650387-B2
Application number	US-202217729359-A
Country	US
Kind code	B2
Filing date	Apr 26, 2022
Priority date	Jul 2, 2019
Publication date	May 16, 2023
Grant date	May 16, 2023

Abstract

Embodiments of the disclosure relate to an optical fiber cable having at least one optical fiber, a cable jacket and a foam layer. The cable jacket includes an inner surface and an outer surface in which the outer surface is an outermost surface of the optical fiber cable. The inner surface is disposed around the at least one optical fiber. The foam layer is disposed between the at least one optical fiber and the cable jacket. The foam layer is made of an extruded product of at least one thermoplastic elastomer (TPE), a chemical foaming agent, and a crosslinking agent. The foam layer has a closed-cell morphology having pores with an average effective circle diameter of less than 100 μm. Further, the foam layer has a compression modulus of less than 1 MPa when measured at 50% strain.

First claim

What is claimed is:

1. A thermoplastic elastomer (TPE) foam, comprising:
an extruded product of 100 parts by weight of a polymer component comprising at least one TPE, 0.1 to 3 parts by weight of a chemical foaming agent, and 0.1 to 2 parts by weight of a crosslinking agent;
wherein the TPE foam comprises a closed-cell morphology having pores with an average effective circle diameter of less than 100 μm;
wherein the TPE foam has a compression modulus of less than 1 MPa at 50% strain as measured according to ASTM 3574; and
wherein the TPE foam has a compression set of no more than 5% as measured after compression to a strain of 60% for ten hours and after four hours of recovery time using a parallel plate compression fixture on a dynamic mechanical analyzer.

2. The TPE foam of claim 1 , wherein the crosslinking agent comprise at least one of dicumyl peroxide, di-tert-butyl peroxide, ditertiary amyl peroxide, tert-butyl peroxide, tert-butyl cumyl peroxide, dibenzoyl peroxide, or tert-butyl hydroperoxide.

3. The TPE foam of claim 1 , wherein the chemical foaming agent comprises at least one of azodicarbonamide, azodiisobutyronitrile, benzenesulfohydrazide, 4,4-oxybenzenesulfonyl semicarbazide, para-toluene sulfonyl semicarbazide, barium azodicarboxylate, N,N′-dimethyl-N,N′-dinitrosoterephthalamide, trihydrazino triazine, or sodium bicarbonate.

4. The TPE foam of claim 1 , wherein the TPE comprises at least one of a polyolefin elastomer, a thermoplastic polyolefin, or a thermoplastic vulcanizate.

5. The TPE foam of claim 1 , wherein the TPE has an unfoamed tensile modulus of at most 10 MPa at 100% secant as measured according ASTM D638.

Assignees

• Corning Res & Dev Corp

Inventors

• Bringuier Anne Germaine
• Cheng Xiaole

Classifications

• G02B6/443 Primary

  Protective covering · CPC title

• B29C48/022 Primary

  characterised by the choice of material · CPC title

• G02B6/4486

  Protective covering · CPC title

• B32B5/18

  characterised by features of a layer {of} foamed material · CPC title

• B29C48/0012

  combined with shaping by internal pressure generated in the material, e.g. foaming · CPC title