BR112018004408B1 - COATED CONDUCTOR - Google Patents

Abstract

PEELABLE CABLE SHEET HAVING ENGINEERED MICROSTRUCTURES AND METHODS FOR MAKING PEELABLE CABLE SHEET HAVING ENGINEERED MICROSTRUCTURES. Clad conductors comprising a conductor and a peelable polymeric coating at least partially surrounding the conductor, wherein the peelable polymeric coating comprises from 1 to 8 microcapillaries defining individual, discrete voids. Methods for making such coated conductors are also disclosed.

Description

FIELD

[001] Various embodiments of the present invention relate to sheaths and cable jackets having microcapillary structures that allow for easy stripping.

INTRODUCTION

[002] Cables generally require access to their core for ease of connection and installation. Generally, cables are designed for maximum protection of internal components, requiring the use of strong materials. As a result, breaking the cable jacket to access these internal components during connection or installation is difficult. For example, when connecting cables, a knowledgeable installer must often use sharp cutting tools to open the jacket and use special tools to access the cable's internal components. Network installation costs and subsequent maintenance or cable replacement can be reduced by using cables in which the internal components are easily accessible for ease of connection. While some attempts have been made to provide cable jackets with easy access to internal components, such advances often come at the expense of the jackets' mechanical properties.

SUMMARY

[003] One embodiment is a coated conductor, comprising: (a) a conductor; and (b) a peelable polymeric coating surrounding at least a portion of said conductor, wherein said peelable polymeric coating comprises a polymeric matrix material and in the range of 1 to 8 microcapillaries extending substantially in the direction of elongation of said coating peelable polymeric material, wherein said microcapillaries define individual, discrete voids.

BRIEF DESCRIPTION OF THE DRAWINGS

[004] Reference is made to the attached drawings in which:

[005] FIG. 1 is a perspective view, partially in cross-section, of an extruder with die assembly for making a microcapillary film;

[006] FIG. 2A is a longitudinal sectional view of a microcapillary film;

[007] FIGS. 2B and 2C are cross-sectional views of a microcapillary film;

[008] FIG. 2D is an elevated view of a microcapillary film;

[009] FIG. 2E is a segment 2E of a longitudinal sectional view of the microcapillary film as shown in Fig. 2B;

[0010] FIG. 2F is an exploded view of a microcapillary film;

[0011] FIG. 2G is a cross-sectional view of a microcapillary film particularly representing a single layer embodiment;

[0012] FIGS. 3A and 3B are schematic perspective views of various extruder assembly configurations including an annular die assembly for manufacturing coextruded multilayer annular microcapillary products and air-filled multilayer annular microcapillary products, respectively;

[0013] FIG. 4A is a schematic view of a microcapillary film with microcapillaries with a fluid therein;

[0014] FIG. 4B is a cross-sectional view of a coextruded microcapillary film;

[0015] FIG. 4C is a cross-sectional view of an inventive air-filled microcapillary film;

[0016] FIG. 5 is a schematic view of an annular microcapillary tubing extruded from a die assembly;

[0017] FIGS. 6A and 6B are perspective views of an annular microcapillary tubing;

[0018] FIGS. 7A-7D are partial cross-sectional, longitudinal cross-sectional, final and detailed views, respectively, of an annular die assembly in an asymmetric flow configuration;

[0019] FIGS. 8A-8D are partial cross-sectional, longitudinal cross-sectional, final and detailed views, respectively, of an annular die assembly in a flow-symmetrical configuration;

[0020] FIGS. 9A-9D are partial cross-sectional, longitudinal cross-sectional, final, and detailed views, respectively, of an annular die assembly in a flow-symmetric configuration; It is

[0021] FIG. 10 is a perspective view of a die insert for an annular die assembly.

DETAILED DESCRIPTION

[0022] The present disclosure relates to die sets and extruders for producing annular microcapillary products. Such annular microcapillary products can be used in the manufacture of wire and cable manufacturing articles, such as forming at least a portion of a polymeric jacket (e.g., a coating) or a polymeric protective component surrounding a conductive core.

[0023] The die assembly includes an annular die insert positioned between the manifolds and defining material flow channels therebetween to extrude layers of a thermoplastic material. The die insert has a tip with microcapillary flow channels on an outer surface for inserting microcapillary material into microcapillaries between extruded layers of thermoplastic material. The microcapillaries can contain a variety of materials, such as other thermoplastic materials or elastomeric materials, or they can just be empty space microcapillaries (i.e., containing a gas, such as air). Die sets for producing annular microcapillary products are a variation of the die sets for producing microcapillary films both described in detail below.

Microcapillary Film Extruder

[0024] FIG. 1 depicts an example extruder (100) used to form a polymeric film (110) with microcapillaries (103). The extruder (100) includes a material housing (105), a material hopper (107), a screw (109), a die assembly (111) and electronics (115). The extruder (100) is shown partially in cross-section to reveal the screw (109) within the material housing (105). While a screw-type extruder is depicted, a variety of extruders (eg, single screw, twin screw, etc.) can be used to extrude material through the extruder (100) and die assembly (111). One or more extruders can be used with one or more die sets. Electronics (115) may include, for example, controllers, processors, motors and other equipment used to operate the extruder.

[0025] The raw materials (eg thermoplastic materials) (117) are placed in the material hopper (107) and passed into the housing (105) for mixing. The raw materials (117) are heated and mixed by turning the screw (109) rotatably positioned in the housing (105) of the extruder (100). A motor (121) can be provided to drive the screw (109) or another driver to advance the raw materials (117). Heat and pressure are applied according to the schematic representation of a heat source T and a pressure source P (e.g. screw (109)) respectively to the mixed material to force the raw material (117 ) through the matrix assembly (111) as indicated by the arrow. The raw materials (117) are melted and transported through the extruder (100) and die assembly (111). The molten raw material (117) passes through the die assembly (111) and is formed into the desired shape and cross-section (herein referred to as the "profile"). Die assembly (111) may be configured to extrude molten feedstock (117) into thin sheets of multilayer polymeric film (110) as described herein.

microcapillary film

[0026] FIGS. 2A-2F depict various views of a multilayer film (210) that may be produced, for example, by the extruder (100) and die assembly (111) of FIG. 1. As shown in FIGS. 2A-2F, the multilayer film 210 is a microcapillary film. The multilayer film (210) is shown as consisting of multiple layers (250a, b) of thermoplastic material. The film (210) also has channels (220) positioned between the layers (250a, b).

[0027] The multilayer film (210) can also have an elongated profile as shown in Fig. 2C. This profile is represented as having a wider width W relative to its thickness T. The thickness T can be in the range of 100 to 2000 μm (for example, 250 to 2000 μm). The channels (220) can have a dimension Φ (e.g. a width or diameter) in the range of 50 to 500 µm (e.g. 100 to 500 µm or 250 to 500 µm) and have a spacing S between the channels ( 220) in the range 50 to 500 μm (for example, 100 to 500 μm, or 250 to 500 μm). In addition, selected dimensions can be proportionally set. For example, the channel dimension Φ might be a diameter of about 30% of the thickness T.

[0028] As shown, the layers (250a, b) are made of a matrix thermoplastic material and the channels (220) have a channel fluid (212). The channel fluid can comprise, for example, various materials, such as air, gas, polymers, etc., as will be described later in this document. Each layer (250a, b) of the multilayer film (210) can be made from a variety of polymers, such as those described below. Each layer can be made of the same material or a different material. Although only two layers (250a, b) are shown, the multilayer film (210) can have any number of layers.

[0029] It should be noted that when the same thermoplastic material is used for the layers (250a, b), then a single layer (250) may result in the final product due to the merging of the two streams of the matrix layers composed of the same polymer in a molten state, melting just before exiting the die. This phenomenon is depicted in FIG. 2g.

[0030] The channels (220) can be positioned between one or more sets of layers (250a, b) to define the microcapillaries (252) therein. Channel fluid (212) may be provided in the channels (220). Various channel numbers (220) can be provided as desired. Multiple layers can also have the same or different profiles (or cross sections). Characteristics, such as the shape of the layers (250a, b) and/or the channels (220) of the film (210), can be defined by the configuration of the die assembly used to extrude the matrix material, as will be described in detail below. more complete in this document.

[0031] The microcapillary film (210) has a first end (214) and a second end (216). The one or more channels (220) are arranged in parallel in the matrix (218) from the first end (214) to the second end (216). One or more channels (220) may have a diameter of at least 250 µm, or in the range from 250 to 1990 µm, from 250 to 990 µm, from 250 to 890 µm, from 250 to 790 µm, from 250 to 690 µm, or from 250 to 590 µm. The or more channels (220) may have a cross-sectional shape selected from the group consisting of circular, rectangular, oval, star, diamond, triangular, square, hexagonal, pentagonal, octagonal and similar combinations thereof.

[0032] The matrix (218) comprises one or more thermoplastic matrix materials. Such thermoplastic matrix materials include, but are not limited to, polyolefins (e.g., polyethylenes, polypropylenes, etc.); polyamides (e.g. nylon 6); polyvinylidene chloride; polyvinylidene fluoride; polycarbonate; polystyrene; polyethylene terephthalate; polyurethane; and polyester. Specific examples of thermoplastic matrix materials include those listed on pages 5 to 11 of PCT Published Application WO 2012/094315 entitled "Microcapillary Films and Foams Containing Functional Filler Materials", which are incorporated herein by reference.

[0033] The one or more channel fluids (212) may include a variety of fluids, such as air, other gases or thermoplastic channel material. Channel thermoplastic materials include, but are not limited to, polyolefins (eg, polyethylenes, polypropylenes, etc.); polyamides (e.g. nylon 6); polyvinylidene chloride; polyvinylidene fluoride; polycarbonate; polystyrene; polyethylene terephthalate; polyurethane; and polyester. As with the matrix materials (218) discussed above, specific examples of thermoplastic materials suitable for use as channel fluids (212) include those listed on pages 5 to 11 of PCT Published Application WO 2012/094315.

Annular microcapillary product extruder sets

[0034] FIGS. 3A and 3B depict examples of extruder assemblies (300a, b) used to form a multi-layer annular microcapillary product (310a, b) with microcapillaries (303). The sets of extruders (300a, b) can be similar to the extruder (100) of FIG. 1, with the exception that the extruder assemblies (300a, b) include multiple extruders (100a, b, c) with matched annular microcapillary coextrusion die assemblies (311a, b) operatively connected thereto. The annular die assemblies (311a, b) have die inserts (353) configured to extrude annular microcapillary products, such as film (310) as shown in FIGS. 4A-4C, tubing (310a) as shown in FIGS. 5, 6A and 6B, and/or the molded shapes (310b) as shown in FIG. 3B.

[0035] FIG. 3A depicts a first configuration of an extruder assembly (300a) with three extruders (100a, b, c) operatively connected to the combined annular microcapillary coextrusion die assembly (311a). In one example, two of the three extruders may be die extruders (100a, b) used to feed thermoplastic material (eg, polymer) (117) to the die assembly (311a) to form layers of the annular microcapillary product (310a). One third of the extruders may be a microcapillary (or core layer) extruder (100c) to deliver a microcapillary material, such as a thermoplastic material (e.g., polymer melt) (117), into the microcapillaries (303) to form a microcapillary phase (or central layer).

[0036] A die insert (353) is provided in the die assembly (311a) to combine the thermoplastic material (117) from the extruders (100a, b, c) into the annular microcapillary product (310a). As shown in FIG. 3A, the annular microcapillary product may be a blown tube (310a) extruded upward through the die insert (353) and out of the die assembly (311a). Annular fluid (312a) from a fluid source (319a) may be passed through the annular microcapillary product (310a) to form the annular microcapillary tubing (310a) during extrusion as shown in FIG. 3A, or be provided with a molding device (354) configured to produce an annular microcapillary product in the form of an annular microcapillary molding (or shaped product), such as a bottle (310b), shown in FIG. 3B.

[0037] FIG. 3B shows a second configuration of an extruder assembly (300b). The extruder assembly (300b) is similar to the extruder assembly (300a), with the difference that the microcapillary extruder (100c) has been replaced by a microcapillary fluid source (319b). The extruders (100a, b) extrude thermoplastic material (as in the example of Figure 3A) and the microcapillary fluid source (319b) can emit microcapillary material in the form of a microcapillary fluid (312b) through the die insert (353) of the assembly. matrix (311b). The two die extruders (100a, b) emit thermoplastic layers, with the microcapillary fluid source (319b) emitting microcapillary fluid (312b) into the microcapillaries (303) between them to form the annular microcapillary product (310b). In this version, the annular die assembly 311b can form films or blown products as in FIG. 3A, or be provided with a molding agent (354) configured to produce an annular microcapillary product in the form of an annular microcapillary molding, such as a bottle (310b).

[0038] While FIGS. 3A and 3B show each extruder (100a, b, c) as having a separate material housing (105), material hopper (107), screw (109), electronics (115), motor (121), part of the extruders or all of them (100) can be combined. For example, extruders (100a, b, c) may have their own hopper (107), and share certain components, such as electronics (115) and die assembly (311a, b). In some cases, the fluid sources (319a, b) may be the same fluid source supplying the same fluid (312a, b), such as air.

[0039] The die assemblies (311a, b) may be operatively connected to the extruders (100a, b, c) in a desired orientation, such as a vertical perpendicular position, as shown in FIG. 3A, a downward vertical position, as shown in FIG. 3B, or a horizontal position, as shown in FIG. 1. One or more extruders can be used to provide the polymeric matrix material that forms the layers and one or more sources of material, such as an extruder (100c) and/or microcapillary fluid source (319b), can be used to provide the microcapillary material. In addition, as described in more detail below, die sets can be configured in a cross position for coextrusion with a conductive core.

Annular microcapillary products

[0040] FIGS. 4A-4C depict various views of an annular microcapillary product that may be in the form of a film (310, 310') produced, for example, by the extruders (300a, b) and die assemblies (311a, b) of FIG. 3A and/or 3B. As shown in FIGS. 4A and 4B, the annular microcapillary product (310) may be similar to film (210), with the difference that the annular microcapillary product (310) is formed from the annular matrix assemblies (311a, B) in matrix layers polymeric (450a, b) with microcapillaries (303, 303') in them. The polymeric matrix layers (450a, b) collectively form a polymeric matrix (418) of the annular microcapillary product (310). The layers (450a, b) have parallel, linear channels (320) that define microcapillaries (303) therein.

[0041] As shown in FIGS. 4B and 4C, the annular microcapillary product (310, 310') can be extruded with various microcapillary materials (117) or microcapillary fluid (312b) therein. The microcapillaries can be formed into channels (320, 320') of various cross-sectional shapes. In the example of FIG. 4B, the channels (320) have an arcuate cross-section defining the microcapillaries (303) with the microcapillary material (117) therein. The microcapillary material (117) is in the channels (320) between the matrix layers (450a, b) that form the polymeric matrix (418). The microcapillary material (117) forms a core layer between the polymeric matrix layers (450a, b).

[0042] In the example of FIG. 4C, the channels (320') have an elliptical cross-section defining microcapillaries (303') with microcapillary material (312b) therein. The microcapillary material (312b) is represented as fluid (eg, air) in the channels (320') between the layers (450a, b) that form the polymeric matrix (418).

[0043] It should be noted that, as with the films described above, the annular microcapillary product can take the form of a single layer product when the same matrix material is used for the layers (450a, b). This is due to the merging of the two streams of the matrix layers in a molten state which merge just before exiting the matrix.

[0044] The materials used to form the annular microcapillary products as described herein can be selected for a particular application. For example, the material can be a plastic, such as a thermoplastic or thermosetting material. When a thermoplastic material is used, the thermoplastic material (117) forming the polymeric matrix (418) and/or the microcapillary material (117) can be selected from those materials useful in forming the film (210) as described above. Accordingly, annular microcapillary products can be made from various materials, such as polyolefins (e.g., polyethylene or polypropylene). For example, in FIGS. 4A and 4B, the polymeric matrix (418) can be a low density polyethylene and the microcapillary material (117) can be polypropylene. As another example, in FIG. 4C the polymeric matrix (418) can be made of low density polyethylene with air as microcapillary material (312b).

[0045] Referring to FIG. 5, the fluid source (319a) can pass annular fluid (e.g., air) (312a) through the annular microcapillary product (310a) to support the tubular shape during extrusion. The matrix assembly (311a) can form the multilayered annular microcapillary product (310a, 310a') into a tubular shape as shown in FIGS. 6A-6B.

[0046] As also shown by FIGS. 6A and 6B, the thermoplastic material-forming parts of the multi-layer annular microcapillary product (310a, 310a') can be varied. In the example shown in FIGS. 4A, 4B and 6A, the polymeric matrices (418) of the layers (450a, b) may have a different material than the microcapillary material (117) in the microcapillaries (303) as schematically indicated by the black channels (320) and the white polymeric matrix (418). In another example, as shown in FIG. 6B, the layers (450a, b) forming a polymeric matrix (418) and the microcapillary material (303) can be made of the same material, such as low density polyethylene, so that the polymeric matrix (418) and the channels (320) are both represented as black.

Die sets for annular microcapillary products

[0047] FIGS. 7A-9D depict example configurations of matrix sets (711, 811, 911) usable as matrix set (311). While FIGS. 7A-9D show examples of possible array array configurations, combinations and/or variations of the various examples can be used to provide the desired multilayer annular microcapillary product, such as those shown in the examples of FIGs. 4A-6B.

[0048] FIGS. Figures 7A-7D depict partial cross-sectional, longitudinal cross-sectional, end-sectional and detailed cross-sectional views, respectively, of die assembly (711). FIGS. 8A-8D depict detailed partial cross-sectional, longitudinal cross-sectional, and final cross-sectional views, respectively, of die assembly (811). FIGS 9A-9D depict detailed partial cross-sectional, longitudinal cross-sectional, and final cross-sectional views, respectively, of die assembly (911). The die assemblies (711, 811) can be used, for example, with the extruder assembly (300a) of FIG. 3A and the die assembly 911 can be used, for example, with the extruder assembly 300b of FIG. 3B to form annular microcapillary products such as those described herein.

[0049] As shown in FIGS. 7A-7D, the die assembly (711) includes a housing (758), an inner manifold (760), an outer manifold (762), a cone (764) and a die insert (768). The housing (758) is a tubular member shaped to receive the outer manifold (762). The outer manifold (762), die insert (768) and inner manifold (760) are each flanged elements stacked and concentrically received within the housing (758). While an inner manifold (760) and an outer manifold (762) are depicted, one or more inner and/or outer manifolds or other devices capable of providing flow channels for forming layers of the polymeric matrix may be provided.

[0050] The die insert (768) is positioned between the outer distributor (762) and the inner distributor (760). The inner manifold (760) has the cone (764) at one end thereof which extends through the die insert (768) and the outer manifold (762) and into the housing (758). The die assembly (711) may be provided with connectors, such as screws (not shown), for connecting portions of the die assembly (711).

[0051] Referring now to FIG. 7B, annular die channels (774a, b) are defined between the housing (758) and the outer manifold (762) and between the die insert (768) and the inner manifold (760), respectively. The thermoplastic material (117) is shown passing through the matrix channels (774a, b) as indicated by the arrows to form the layers (450a, b) of the multi-layered annular microcapillary product (710). The annular microcapillary product (710) can be any of the annular microcapillary products described herein, such as (310a, b).

[0052] A microcapillary channel (776) is also defined between the matrix insert (768) and the external distributor (762). The microcapillary channel (776) may be coupled to the source of microcapillary material to pass the microcapillary material (117, 312b) through the matrix assembly (711) and between the layers (450a, b) to form the microcapillaries (303) therein. . The fluid channel (778) extends through the inner manifold (760) and cone (764). Annular fluid (312a) from the fluid source (319a) flows through the fluid channel (778) and into the product (710a).

[0053] The die insert (768) may be positioned concentrically between the inner manifold (760) and the outer manifold (762) to provide uniform distribution of polymer melt flow through the die assembly (711). The matrix insert (762) may be provided with a distribution channel (781) along an outer surface thereof to facilitate the flow of microcapillary material (117/312b) therethrough.

[0054] The matrix channels (774a, b) and the microcapillary channel (776) converge at the convergence (779) and pass through an extrusion outlet (780) such that the thermoplastic material flowing through the matrix channels (774a, b) forms layers (450a, b) with microcapillary material (117/312b) from the microcapillary channel (776) between them. The outer manifold (762) and die insert (768) each terminate in an outer nose (777a) and an insert nose (777b), respectively. As shown in FIG. 7D, the outer nose (777a) extends a distance A towards the extrusion outlet (780) and/or a distance A farther from the extrusion outlet (780) than the nose (777b).

[0055] The die sets (811, 911) of FIGS. 8A-9D may be similar to the matrix assembly 711 of FIGS. 7A-7D, except that a position of the noses (777a, b, 977a, b) of the die insert (768, 968) relative to the outer manifold (762) can be varied. The position of the noses can be adjusted to define a flow pattern, such as asymmetrical or symmetrical throughout. As shown in FIGS. 7A-7D, the die assembly (711) is in an asymmetric flow configuration with the nose (777b) of the die insert (768) positioned at distance A from the nose (777a) of the outer manifold (762). As shown in FIGS. 8A-8D, the die assembly (811) is in symmetric flow configuration with the noses (777a, b) of the die insert (768) and the outer manifold (762) is being flushed.

[0056] FIGS. 9A-9D and 10 depict an annular matrix insert (968) provided with features to facilitate the creation of channels (320), microcapillaries (303) and/or insertion of microcapillary material (117-312b) (see, for example, Figures 4A-4B). The die insert (968) includes a base (982), a tubular distributor (984) and a tip (986). The base (982) is a ring-shaped member that forms a flange that extends from a supporting end of the annular microcapillary dispenser (984). The base (982) is supportable between the inner manifold (760) and the outer manifold (762). The outer manifold (762) has an extended nose (977a) and the die insert (968) has an extended nose (977b) positioned flush with one another to define a symmetrical flow configuration through the die assembly (911).

[0057] The tip (986) is an annular member at a flow end of the tubular manifold (984). An inner surface of the tip (986) is angled and shaped to receive one end of the cone (764). The tip (986) has a larger external diameter than the annular microcapillary distributor (984) with an inclined shoulder (990) defined therebetween. An outer surface of the tip (986) has a plurality of parallel, linear microcapillary flow channels (992) for passing the microcapillary material (117/312b) therethrough. The outer manifold 762 terminates in a sharp edge (983a) along the nose (977a) and the tip (986) terminates in a sharp edge (983b) along the nose (977b).

[0058] The annular microcapillary dispenser (984) is an annular member extending between the base (982) and the tip (986). The annular microcapillary dispenser (984) is supportable between a tubular portion of the inner dispenser (760) and the inner dispenser (762). The annular microcapillary dispenser (984) has a passage (988) for receiving the inner dispenser (760).

[0059] The distribution channel (781) can have a variety of configurations. As shown in FIGS. 9A-9D, an outer surface of the annular microcapillary dispenser (984) has the delivery channel (781) at that location for passing material therethrough. The distribution channel (781) may be in fluid communication with the microcapillary material (117/312b) through the microcapillary channel (776), in accordance with the schematic description of FIG. 9B. The distribution channel (781) can be positioned around the matrix insert (968) to direct the microcapillary material around a circumference of the matrix insert (968). The matrix insert (968) and/or distribution channel (781) can be configured to facilitate a desired amount of flow of microcapillary material (117/312b) through the matrix assembly. The distribution channel (781) defines a material flow path for passing the microcapillary material between the matrix insert (968) and the outer distributor (762).

[0060] A small gap can form between the matrix insert (968) and the external distributor (762) that allows the microcapillary material (117/312b) to escape out of the distribution channel (781) to distribute the material microcapillary (117/312b) evenly across the matrix assembly (911). The distribution channel (781) can be in the form of a cavity or channel that extends a desired depth into the die insert (968) and/or the outer manifold (760). For example, as shown in FIGS. 7A-9D, the distribution channel (781) can be a space defined between the outer surface of the die insert (968) and the outer distributor (760). As shown in FIG. 10, the distribution channel (781, 1081) is a helical groove extending along the outer surface of the tubular distributor (984). Part or all of the distribution channel (781, 1081) can be linear, curved, spiral, cross and/or combinations thereof.

coated conductor

[0061] The above-described annular microcapillary products can be used to prepare coated conductors such as a cable. "Cable" and "power cable" mean at least one conductor within a sheath, eg an insulating sheath and/or a protective outer sheath. "Conductor" means one or more wire(s) or fiber(s) for conducting heat, light and/or electricity. The conductor may be a single strand fiber or a multi strand fiber and may be in strand form or tubular form. Non-limiting examples of suitable conductors include metals such as silver, gold, copper, carbon and aluminum. The conductor can also be made from fiber optic glass or plastic. "Wire" means a single wire of conductive metal, for example copper or aluminum, or a single optical fiber. Typically, a cable is two or more strands or optical fibers bonded together, typically in a common insulating sheath and/or a protective jacket. The individual strands or fibers within the sheath may be bare, covered, or insulated. Combination cables can contain both electrical wires and optical fibers. When the cable is a power cable, the cable may be designed for low, medium and/or high voltage applications. Typical cable designs are illustrated in USP 5,246,783, 6,496,629, and 6,714,707. When the cable is a telecommunications cable, the cable can be designed for telephone, local area network (LAN)/data, CATV coaxial, RF coaxial cable or a fiber optic cable.

[0062] The above-described annular microcapillary products can constitute at least one layer of polymeric coating on a cable, which is elongated in the same direction of elongation as the conductor or conductor core of the cable. As such, the polymeric coating can surround at least a portion of the conductor. Around the conductor, the polymeric coating may be in direct contact with the conductor or it may be in indirect contact with the conductor, being placed in one or more interceding layers between the conductor and the polymeric coating. The polymeric coating comprises a polymeric matrix material and a plurality of microcapillaries extending substantially in the direction of elongation of the polymeric coating. In various embodiments, the microcapillaries can be placed radially around the polymeric coating. Furthermore, the microcapillaries may be spaced equidistantly or substantially equidistantly from one another.

[0063] One or more of the above-described arrays of dies for producing annular microcapillary products can be modified to allow a conductor to pass therethrough, thereby allowing the polymeric coating to comprise a polymeric matrix material and a plurality of microcapillaries to be co-extruded in the conductor or in an intervening layer. Such a configuration is commonly known in the art as a cross-array (see, for example, US 2008/0193755 A1, US 2014/0072728 A1 and US 2013/0264092 A1). Specifically, the inner manifold (760) and cone (764) in FIGS. 7A, 8A and 9A can be modified to create a wire or conductor through hole. As one skilled in the art would recognise, all parts close to the die exit can be modified so that the extruded materials are able to coat a conductor or interceding layer, passing through the wire or conductor hole. An additional part with molding pass can be manufactured. Such modifications are well within the capabilities of a person of ordinary skill in the art.

[0064] In an exemplary microcapillary extrusion coating process, a conductive core through an extrusion coating equipment can be pulled by a retractor to move continuously through the wire feed hole of the inner manifold (760) to pass through the projecting end and then pass through the outer die molding passage. While the conductive core is in motion, the polymer melt is pressure injected into the material supply passages, flows towards the spinning casing passage and then into the outlet molding passage to coat the outer surface of the conductive core which is going through the molding pass. Thereafter, the coated conductive core continues to move through the molding passage and out of the die, where it can then be cooled and hardened.

[0065] In preparing the polymer coating, any of the above-described polymers can be used as the polymer matrix material. In various embodiments, the polymer employed as the polymeric matrix material can comprise an ethylene-based polymer. As used herein, "ethylene-based" polymers are polymers prepared from monomers of ethylene as the primary monomer component (i.e., greater than 50 percent by weight ("% by weight")), although other comonomers can also be employed. "Polymer" means a macromolecular compound prepared by reacting (ie, polymerizing) monomers of the same or different types and includes homopolymers and interpolymers. "Interpolymer" means a polymer prepared by polymerizing at least two different types of monomers. This generic term includes copolymers (usually used to refer to polymers prepared from two different types of monomers), and polymers prepared from more than two different types of monomers (e.g., terpolymers (three different types of monomers) and tetrapolymers (four different types of monomers)).

[0066] In various embodiments, the ethylene-based polymer may be an ethylene homopolymer. As used herein, "homopolymer" denotes a polymer comprising repeating units derived from a single type of monomer, but does not exclude residual amounts of other components used in preparing the homopolymer, such as chain transfer agents.

[0067] In one embodiment, the ethylene-based polymer may be an ethylene/alpha-olefin interpolymer ("α-olefin") with an α-olefin content of at least 1% by weight of at least 5 % by weight, at least 10% by weight, at least 15% by weight, at least 20% by weight, or at least 25% by weight based on total interpolymer weight. These interpolymers can have an α-olefin content of less than 50% by weight, less than 45% by weight, less than 40% by weight, or less than 35% by weight based on the total interpolymer weight. When an α-olefin is employed, the α-olefin can be a linear, branched or cyclic C3-20 α-olefin (i.e., having 3 to 20 carbon atoms). Examples of C3-20 α-olefins include propene, 1-butene, 4-methyl-1-pentene, 1-hexane, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene and 1-octadecene . α-olefins can also contain a cyclic structure, such as cyclohexane or cyclopentane, resulting in an α-olefin, such as 3-cyclohexyl-1-propene (allyl cyclohexane) and vinyl cyclohexane. Exemplary ethylene/α-olefin interpolymers include ethylene/propylene, ethylene/1-butene, ethylene/1-hexane, ethylene/1-octene, ethylene/propylene/1-octene, ethylene/propylene/1-butene and ethylene/1 -butene/1-octene.

[0068] Ethylene-based polymers also include interpolymers of ethylene with one or more unsaturated acid monomers or esters, such as unsaturated carboxylic acids or alkyl (alkyl) acrylates. Such monomers include, but are not limited to, vinyl acetate, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, acrylic acid and the like. Therefore, ethylene-based polymers can include interpolymers such as poly(ethylene-co-methyl acrylate) ("EMA"), poly(ethylene-co-ethyl acrylate) ("EEA"), poly(ethylene-co-ethyl acrylate) -butyl acrylate) ("EBA") and poly(ethylene-co-vinyl acetate) ("EVA").

[0069] In various embodiments, the ethylene-based polymer can be used alone or in combination with one or more other types of ethylene-based polymers (for example, a mixture of two or more ethylene-based polymers, which differ in one on the other by monomer composition and content, catalyst preparation method, etc.). If an ethylene-based polymer blend is used, the polymers can be blended by any reactor or in a post-reactor process.

[0070] In one embodiment, the ethylene-based polymer can be a low density polyethylene ("LDPE"). LDPEs are generally highly branched ethylene homopolymers and can be prepared via high pressure processes (ie HP-LDPE). LDPEs suitable for use in the present invention can have a density ranging from 0.91 to 0.94 g/cm3. In various embodiments, the ethylene-based polymer is a high pressure LDPE having a density of at least 0.915 g/cm3 but less than 0.94 g/cm3 or less than 0.93 g/cm3. Polymer densities provided herein are determined according to ASTM International ("ASTM") Method D792. LDPEs suitable for use in the present invention may have a melt index (I 2 ) of less than 20 g/10 min., or in the range of 0.1 to 10 g/10 min., 0.5 to 5 g/10 min. min., 1 to 3 g/10 min., or an I2 of 2 g/10 min. Melt indices given herein are determined according to ASTM method D1238. Unless otherwise noted, melt indices are determined at 190°C and 2.16 kg (ie, I2). Generally, LDPEs have a broad molecular weight distribution ("MWD"), resulting in a relatively high polydispersity index ("PDI"; the ratio of weight average molecular weight to number average molecular weight).

[0071] In one embodiment, the ethylene-based polymer can be a linear low density polyethylene ("LLDPE"). LLDPEs are generally ethylene-based polymers having a heterogeneous comonomer distribution (eg, α-olefin monomer) and are characterized by short-chain branching. For example, the LLDPEs can be copolymers of ethylene and α-olefin monomers, such as those described above. LLDPEs suitable for use in the present invention can have a density ranging from 0.916 to 0.925 g/cm3. LLDPEs suitable for use in the present invention may have a melt index (I 2 ) ranging from 1 to 20 g/10 min. or 3 to 8 g/10 min.

[0072] In one embodiment, the ethylene-based polymer can be a very low density polyethylene ("VLDPE"). VLDPEs may also be known in the art as ultra low density polyethylenes or ULDPEs. VLDPEs are generally ethylene-based polymers having a heterogeneous comonomer distribution (eg, α-olefin monomer) and are characterized by short-chain branching. For example, VLDPEs can be copolymers of ethylene and α-olefin monomers, such as one or more of those α-olefin monomers described above. VLDPEs suitable for use in the present invention can have a density ranging from 0.87-0.915/cm3. VLDPEs suitable for use in the present invention may have a melt index (I 2 ) ranging from 0.1 to 20 g/10 min. or 0.3 to 5 g/10 min.

[0073] In one embodiment, the ethylene-based polymer can be a medium density polyethylene ("MDPE"). MDPEs are ethylene-based polymers with densities generally ranging from 0.926 to 0.950 g/cm3. In various embodiments, the MDPE can have a density ranging from 0.930 to 0.949 g/cm3, from 0.940 to 0.949 g/cm3, or from 0.943 to 0.946 g/cm3. MDPE can have a melt index (I2) ranging from 0.1 g/10 min, or 0.2 g/10 min, or 0.3 g/10 min, or 0.4 g/10 min, to 5.0 g/10 min or 4.0 g/10 min or 3.0 g/10 min or 2.0 g/10 min or 1.0 g/10 min.

[0074] In one embodiment, the ethylene-based polymer can be a high density polyethylene ("HDPE"). HDPEs are ethylene-based polymers generally having densities greater than 0.940 g/cm3. In one embodiment, the HDPE has a density of 0.945 to 0.97 g/cm 3 as determined in accordance with ASTM D-792. HDPE can have a maximum melting temperature of at least 130°C, or 132 to 134°C. HDPE can have a melt index (I2) ranging from 0.1 g/10 min, or 0.2 g/10 min, or 0.3 g/10 min, or 0.4 g/10 min, to 5.0 g/10 min or 4.0 g/10 min or 3.0 g/10 min or 2.0 g/10 min or 1.0 g/10 min or 0.5 g/10 min. Additionally, HDPE can have a PDI in the range of 1.0 to 30.0, or in the range of 2.0 to 15.0, as determined by gel permeation chromatography.

[0075] In one embodiment, the ethylene-based polymer may comprise a combination of any two or more of the above-described ethylene-based polymers.

[0076] In one embodiment, the polymeric matrix material may comprise LDPE. In one embodiment, the polymeric matrix material is LDPE.

[0077] In one embodiment, the polymeric matrix material may comprise MDPE. In one embodiment, the polymeric matrix material is MDPE.

[0078] The production processes used for preparing ethylene-based polymers are wide and varied and known in the art. Any conventional or futurely discovered production process for producing ethylene-based polymers having the properties described above can be employed for preparing the ethylene-based polymers described herein. In general, the polymerization can be carried out under conditions known in the art for polymerization reactions of the Ziegler-Natta or Kaminsky-Sinn type, i.e. at temperatures from 0 to 250°C or 30 or 200°C and pressures from atmospheric to 10,000 atmospheres (1.013 megaPascal ("MPa")). In most polymerization reactions, the molar ratio of catalyst to polymerizable compounds used is from 10-12:1 to 10-1:1 or from 10-9:1 to 10-5:1.

[0079] Examples of suitable commercially available ethyl-based polymers include, but are not limited to, AXELERONTM GP C-0588 BK (LDPE), AXELERONTM FO 6548 BK (MDPE), AXELERON™ GP A-7530 NT (LLDPE), AXELERON ™ GP G-6059 BK (LLDPE), AXELERON™ GP K-3479 BK (HDPE), AXELERON™ GP A-1310 NT (HDPE), and AXELERON™ FO B-6549 NT (MDPE), all of which are commercially available at The Dow Chemical Company, Midland, MI, USA.

[0080] Suitable polypropylene-based polymers such as homopolymer, random copolymer, heterophasic copolymer and high crystalline homopolymer polypropylenes are commercially available from Braskem Corp.

[0081] In preparing the polymer coating, any of the above-described materials can also be used as the microcapillary material.

[0082] In various embodiments, the microcapillary material is a gas. In one or more embodiments, the microcapillary material is air. In such embodiments, the microcapillaries define individual, discrete voids that are completely surrounded by the polymeric matrix material viewed as a cross section orthogonal to the direction of elongation of the microcapillaries.

[0083] In one or more embodiments, the microcapillary material may be an elastomeric microcapillary material. As known in the art, elastomers are defined as materials that experience large reversible deformations under relatively low stress. In any embodiment in which the microcapillaries are filled with a polymeric microcapillary material, the microcapillaries can define individual, discrete polymer-filled segments that are completely surrounded by the polymeric matrix material when viewed as a cross-section orthogonal to the direction of elongation of the microcapillaries.

[0084] In various embodiments, the elastomer may be an olefin elastomer. Olefin elastomers include both polyolefin homopolymers and interpolymers. Examples of polyolefin interpolymers are ethylene/α-olefin interpolymers and propylene/α-olefin interpolymers. In such embodiments, the α-olefin can be any of those described above in relation to the ethylene-based polymer. Exemplary polyolefin copolymers include ethylene/propylene, ethylene/butene, ethylene/1-hexene, ethylene/1-octene, ethylene/styrene, and the like. Illustrative terpolymers include ethylene/propylene/1-octene, ethylene/propylene/butene, ethylene/butene/1-octene and ethylene/butene/styrene. The copolymers can be random or block.

[0085] Olefin elastomers may also comprise one or more functional groups, such as an unsaturated ester or acid or silane, and these elastomers (polyolefins) are well known and can be prepared by conventional high-pressure techniques. The unsaturated esters can be alkyl acrylates, alkyl methacrylates or vinyl carboxylates. Alkyl groups can have from 1 to 8 carbon atoms and preferably from 1 to 4 carbon atoms. Carboxylate groups can have from 2 to 8 carbon atoms and preferably from 2 to 5 carbon atoms. The portion of the copolymer assigned to the ester comonomer can range from 1 to 50 weight percent based on the weight of the copolymer. Examples of acrylates and methacrylates include, but are not limited to, ethyl acrylate, methyl acrylate, methyl methacrylate, t-butyl acrylate, n-butyl acrylate, n-butyl methacrylate, and 2-ethylhexyl acrylate. Examples of vinyl carboxylates are vinyl acetate, vinyl propionate and vinyl butanoate. Examples of unsaturated acids include acrylic acids or maleic acids. An example of an unsaturated silane is vinyl trialkyloxysilane (eg, vinyl trimethoxysilane and vinyl triethoxysilane).

[0086] More specific examples of the olefin elastomers useful in this invention include very low density polyethylene ("VLDPE") (e.g., polyethylene ethylene/1-hexene FLEXOMERTM made by The Dow Chemical Company), ethylene/α- homogeneously branched linear olefin polymers (e.g. TAFMERTM by Mitsui Petrochemicals Company Limited and EXACTTM by Exxon Chemical Company), and homogeneously branched substantially linear ethylene/α-olefin polymers (e.g. polyethylene AFFINITYTM and ENGAGETM and ENGAGETM available from The Dow Chemical Company ).

[0087] Olefin elastomers useful herein also include propylene, butene and other alkene-based copolymers, for example, copolymers comprising most units derived from propylene and a minority of units derived from another α-olefin (including ethylene). Examples of propylene polymers useful herein include VERSIFYTM polymers available from The Dow Chemical Company and VISTAMAXXTM polymers available from ExxonMobil Chemical Company.

[0088] Olefin elastomers may also include ethylene-propylene-diene monomer elastomers ("EPDM") and chlorinated polyethylenes ("CPE"). Commercial examples of suitable EPDMs include NORDEL™ EPDMs, available from The Dow Chemical Company. Commercial examples of suitable CPEs include TYRINTM CPEs, available from The Dow Chemical Company.

[0089] Olefin elastomers, in particular ethylene elastomers, may have a density less than 0.91 g/cm3 or less than 0.90 g/cm3. Ethylene copolymers typically have a density greater than 0.85 g/cm3 or greater than 0.86 g/cm3. Olefin elastomers can have a melt index (I2) greater than 0.10 g/10 min. or greater than 1 g/10 min. Olefin elastomers can have a melt index of less than 500 g/10 min. or less than 100 g/10 min.

[0090] Other suitable olefin elastomers include olefin block copolymers (such as those commercially available under the trade name INFUSETM from The Dow Chemical Company, Midland, MI, USA), mesophase separated multiple olefin block interpolymers (as described in US Patent 7,947,793) and olefin block composites (as described in US Patent Application Publication 2008/0269412, published October 30, 2008).

[0091] In various embodiments, the elastomer useful as a microcapillary material can be a non-olefinic elastomer. Non-olefin elastomers useful herein include silicone and urethane elastomers, styrene butadiene rubber ("SBR"), nitrile rubber, chloroprene, fluoroelastomers, perfluoroelastomers, polyether block amides, and chlorosulfonated polyethylene. Silicone elastomers are polyorganosiloxanes typically with a RaSiO(4-a)/2 average unit formula which may have a linear or partially branched structure, but is preferably linear. Each R can be the same or different. R is a substituted or unsubstituted monovalent hydrocarbyl group which may be, for example, an alkyl group such as a methyl, ethyl, propyl, butyl and octyl group; aryl groups such as phenyl and tolyl groups; aralkyl groups; alkenyl groups, for example vinyl, allyl, butenyl, hexenyl and heptenyl groups; and halogenated alkyl groups, for example chloropropyl and 3,3,3-trifluoropropyl groups. The polyorganosiloxane can be terminated with any of the above groups or with hydroxyl groups. When R is an alkenyl group, the alkenyl group is preferably a vinyl or hexenyl group. Indeed, alkenyl groups can be present in the polyorganosiloxane in terminal groups and/or polymer side chains.

[0092] Representative silicone rubbers or polyorganosiloxanes include, but are not limited to, dimethylvinylsiloxy-terminated polydimethylsiloxane, trimethylsiloxy-terminated polydimethylsiloxane, trimethylsiloxy-terminated copolymer of methylvinylsiloxane and dimethylsiloxane, dimethylvinylsiloxy-terminated copolymer of methylvinylsiloxane and dimethylsiloxane, dimethylvinylsiloxane-terminated polydimethylsiloxane in dimethylhydroxysiloxy, dimethylhydroxysiloxy-terminated copolymer of methylvinylsiloxane and dimethylsiloxane, methylvinylhydroxysiloxy-terminated copolymer of methylvinylsiloxane and dimethylsiloxane, dimethylhexenylsiloxy-terminated polydimethylsiloxane, trimethylsiloxy-terminated copolymer of methylhexenylsiloxane and dimethylsiloxane, dimethylhexenylsiloxy-terminated copolymer exenylsiloxy of methylhexenylsiloxane and dimethylsiloxane, dimethylvinylsiloxy-terminated copolymer of methylphenylsiloxane and dimethylsiloxane, dimethylhexenylsiloxy-terminated copolymer of methylphenylsiloxane and dimethylsiloxane, dimethylvinylsiloxy-terminated copolymer of (3,3,3-trifluoropropyl) siloxane and dimethylsiloxane and dimethyl-dimethylsiloxane-terminated copolymer hexenylsiloxy of (3,3,3-trifluoropropyl) siloxane and dimethylsiloxane (3,3,3-trifluoropropyl).

[0093] Urethane elastomers are prepared from reactive polymers such as polyethers and polyesters and isocyanate-functional organic compounds. A typical example is the reaction product of a dihydroxy functional polyether and/or a trihydroxy functional polyether with toluene diisocyanate in such a way that all the hydroxy is reacted to form urethane linkages leaving isocyanate groups for reaction. additional. This type of reaction product is called a prepolymer which can cure on its own on exposure to moisture or by the stoichiometric addition of polycarbinols or other polyfunctional reactive materials that react with isocyanates. Urethane elastomers are commercially prepared with various ratios of isocyanate compounds and polyethers or polyesters. The most common urethane elastomers are those containing polyethers or polyesters with hydroxyl capacity and polyfunctional, low molecular weight isocyanates. Another common material for use with hydroxyl functional polyethers and polyesters is toluene diisocyanate.

[0094] Non-limiting examples of suitable urethane rubbers include PELLETHANET™ thermoplastic polyurethane elastomers available from the Lubrizol Corporation; ESTANETM thermoplastic polyurethanes, TECOFLEXTM thermoplastic polyurethanes, CARBOTHANETM thermoplastic polyurethanes, TECOPHILICTM thermoplastic polyurethanes, TECOPLASTTM thermoplastic polyurethanes, and TECOTHANETM thermoplastic polyurethanes, all available from Noveon; ELASTOLLANTM thermoplastic polyurethanes and other thermoplastic polyurethanes available from BASF; and additional thermoplastic polyurethane materials available from Bayer, Huntsman, Lubrizol Corporation, Merquinsa and other suppliers. Preferred urethane rubbers are so-called laminable urethanes, such as TSI Industries MILLATHANET™ grades.

[0095] Additional information on these urethane materials can be found in Golding, Polymers and Resins, Van Nostrande, 1959, pages 325 et seq. and Saunders and Frisch, Polyurethanes, Chemistry and Technology, Part II, Interscience Publishers, 1964, among others.

[0096] Commercial elastomers suitably available for use as a microcapillary material include, but are not limited to, ENGAGETM polyolefin elastomer available from The Dow Chemical Company, Midland, MI, USA. A specific example of such an elastomer is ENGAGETM 8200, which is an ethylene/octene copolymer having a melt index (I 2 ) of 5.0 and a density of 0.870 g/cm 3 .

[0097] In modalities where an elastomer microcapillary material is used, it may be desirable that the matrix material has greater strength, abrasion resistance, density and/or flexural modulus in relation to the elastomer. This combination provides a polymeric coating with a tough outer layer but with increased flexibility compared to a coating formed completely from the same matrix material. For example, in various embodiments, the polymeric coating can have one or more of the above-described elastomers such as the microcapillary material with an ethylene-based polymer, a polyamide (e.g., nylon 6), polybutylene terephthalate ("PBT"), polyethylene terephthalate ("PET"), a polycarbonate, or combinations of two or more thereof as a polymeric matrix material. In various embodiments, the polymeric coating may comprise an olefinic elastomer as the microcapillary material, and the polymeric matrix material may be selected from the group consisting of HDPE, MDPE, LLDPE, LDPE, a polyamide, PBT, PET, a polycarbonate, or combinations of the two. or more of the same. In one or more embodiments, the microcapillary material can comprise an ethylene/octene copolymer olefin elastomer and the polymeric matrix material can comprise MDPE.

[0098] The above-described polymeric matrix material, the microcapillary material, or both, may contain one or more additives, such as those typically used in the preparation of cable coatings. For example, the polymer matrix material, the microcapillary material, or both can optionally contain a non-conductive carbon black commonly used in cable sheaths. In various embodiments, the amount of a carbon black in the composition can be greater than zero (>0), typically 1, more typically 2, and up to 3% by weight, based on the total weight of the composition. In various embodiments, the composition can optionally include a conductive filler, such as a conductive carbon black, metal fibers, powders or carbon nanotubes, at a high level for semiconductor applications.

[0099] Non-limiting examples of conventional carbon blacks include the grades described by ASTM N550, N472, N351, N110 and N660, Ketjen blacks, furnace blacks and acetylene blacks. Other non-limiting examples of suitable carbon blacks include those sold under the trademarks BLACK PEARLS®, CSX®, ELFTEX®, MOGUL®, MONARCH®, REGAL® and VULCAN®, available from Cabot.

[00100] The polymeric matrix material, the microcapillary material, or both, may optionally contain one or more additional additives, which are generally added in conventional amounts, either neat or as part of a masterbatch. Such additives include, but are not limited to, flame retardants, processing aids, nucleating agents, foaming agents, crosslinking agents, fillers, pigments or dyes, coupling agents, antioxidants, ultraviolet stabilizers (including UV absorbers) , tackifiers, flame inhibitors, antistatic agents, plasticizers, lubricants, viscosity control agents, antiblocking agents, surfactants, extender oils, acid scavengers, metal deactivators, vulcanizing agents and the like.

[00101] In one or more embodiments, the polymeric matrix material, the microcapillary material, or both, can be crosslinkable. Any suitable methods known in the art can be used to crosslink the matrix material and/or the microcapillary material. Such methods include, but are not limited to, peroxide crosslinking, silane functionalization for moisture crosslinking, UV crosslinking, or e-beam curing. Such crosslinking methods may require the inclusion of certain additives (eg, peroxides), as is known in the art.

[00102] In various embodiments, the polymeric matrix material, the microcapillary material, or both, may contain one or more adhesion modifiers. Adhesion modifiers can be useful to improve the interfacial adhesion between the matrix material and the microcapillary material. Any known or hereafter discovered additive that improves adhesion between two polymeric materials can be used here. Specific examples of suitable adhesion modifiers include, but are not limited to, maleic anhydride ("MAH") grafted resins (e.g., MAH-grafted polyethylene, MAH-grafted ethylene vinyl acetate, MAH-grafted polypropylene), aminated polymers ( e.g., amino-functionalized polyethylene), and the like, and combinations of two or more thereof. MAH-grafted resins are commercially available under the trade name AMPLIFYTM GR from The Dow Chemical Company (Midland, MI, USA) and under the trade name FUSABONDTM from DuPont (Wilmington, DE, USA).

[00103] Non-limiting examples of flame retardants include, but are not limited to, aluminum hydroxide and magnesium hydroxide.

[00104] Non-limiting examples of processing aids include, but are not limited to, fatty amides such as stearamide, oleamide, erucamide or N,N'ethylene bis-stearamide; polyethylene wax; oxidized polyethylene wax; ethylene oxide polymers; ethylene oxide and propylene oxide copolymers; vegetable waxes; petroleum waxes; nonionic surfactants; silicone fluids; polysiloxanes; and fluoroelastomers, such as Viton® available from Dupont Performance Elastomers LLC, or Dynamar™ available from Dyneon LLC.

[00105] A non-limiting example of a nucleating agent includes Hiperform® HPN-20E (calcium salt of 1,2-cyclohexanedicarboxylic acid with zinc stearate) from Milliken Chemicals, Spartanburg, S.C.

[00106] Non-limiting examples of fillers include, but are not limited to, various flame retardants, clays, silica and precipitated silicates, fumed silica, metal sulfides and sulfates, such as molybdenum disulfide and barium sulfate, metallic borates such as barium borate and zinc borate, metal anhydrides such as aluminum anhydride, ground minerals and elastomeric polymers such as EPDM and EPR. If present, fillers are generally added in conventional amounts, for example, from 5% by weight or less to 50% or more by weight based on the weight of the composition.

[00107] In various embodiments, the polymeric coating on the coated conductor can have a thickness in the range of 100 to 3,000 μm, from 500 to 3,000 μm, from 100 to 2,000 μm, from 100 to 1,000 μm, from 200 to 800 μm, from 200 to 600 μm, 300 to 1000 μm, 300 to 900 μm, or 300 to 700 μm. Additionally, the polymeric coating can have a thickness in the range of 10 to 180 mils (254 µm to 4,572 µm).

[00108] In addition, the average diameter of the microcapillaries in the polymeric coating can be at least 50 μm, at least 100 μm, or at least 250 μm. Furthermore, the microcapillaries in the polymer coating can have an average diameter in the range of 50 to 1990 µm, 50 to 990 µm, 50 to 890 µm, 100 to 790 µm, 150 to 690 µm, or 250 to 590 µm μm. It should be noted that, despite the use of the term diameter, the cross-section of microcapillaries need not be round. Instead, they can take on a variety of shapes, such as oblong as shown in FIGS. 4B and 4C. In such cases, "diameter" should be defined as the largest cross-sectional dimension of the microcapillary. This dimension is illustrated as À in FIG. 4B. The "average" diameter should be determined by taking three random cross sections of a polymeric coating, measuring the diameter of each microcapillary and averaging these measurements. Diameter measurement is conducted by cutting a cross-section of the extruded article and viewing under an optical microscope equipped with a scale to measure the diameter of the microcapillary.

[00109] In one or more embodiments, the ratio of the thickness of the polymeric coating to the average diameter of the microcapillaries can be in the range of 2:1 to 400:1

[00110] The spacing of the microcapillaries can vary depending on the desired properties to be achieved. Furthermore, the spacing of the microcapillaries can be defined in relation to the diameter of the microcapillaries. For example, in various embodiments, the microcapillaries can be spaced a distance of less than 1 times the average microcapillary diameter and can be as far as 10 times the average microcapillary diameter. In various embodiments, microcapillaries can be spaced an average of 100 to 5000 µm, an average of 200 to 1000 µm, or an average of 100 to 500 µm. The "spaced" measurement must be determined on an edge-to-edge basis, as illustrated by "s" in FIG. 2C.

[00111] In various embodiments, when the microcapillary material is an elastomer, the polymeric coating may have greater flexibility, especially at low temperature, and reduced density because of the presence of lower density elastomer in the microcapillary.

Peelable Coating

[00112] In one or more embodiments, a coated conductor having a peelable polymeric coating is provided. In such embodiments, the peelable polymeric coating comprises a polymeric matrix material and in the range of 1 to 8 of the above-described microcapillaries that extend substantially in the direction of elongation of the peelable polymeric coating. In various embodiments, the peelable polymeric coating comprises from 1 to 6 microcapillaries, from 1 to 4 microcapillaries, or from 2 to 4 microcapillaries. In various embodiments, the peelable polymeric coating comprises two microcapillaries. In other embodiments, the peelable polymeric coating comprises three microcapillaries. In yet other embodiments, the peelable polymeric coating comprises four microcapillaries.

[00113] In various embodiments, the microcapillaries may be spaced equidistantly or substantially equidistantly radially around the removable polymeric coating. For example, when viewing a cross section of the removable polymeric coating taken orthogonal to the direction of elongation of the microcapillaries, if the removable polymeric coating contains only two microcapillaries, they can be spaced about 180° apart; if the removable polymeric coating contains three microcapillaries, they may be spaced approximately 120° apart; or if the removable polymeric coating contains four microcapillaries, they can be spaced about 90° apart. In other embodiments, and regardless of their radial placement, when viewed as a cross section taken orthogonal to the direction of their elongation, the microcapillaries can be placed in different positions through the thickness of the coating, for example, in sets of two or more capillaries, on top of or in close proximity to one another and separated by a solid wall of matrix material.

[00114] The microcapillaries of the removable polymeric coating can (i) define individual and discreet empty spaces; (ii) comprise an elastomeric polymer having a lower flexural modulus than the polymeric matrix material; (iii) comprise a non-polymeric, low viscosity filler material capable of being pumped into the microcapillaries; or (iv) combinations of two or more of (i) - (iii).

[00115] Whether the microcapillaries are filled or empty, the microcapillaries can be completely surrounded by the polymer matrix material when viewed as a cross section orthogonal to the direction of elongation of the microcapillaries. In various embodiments, the aggregate of space defined by microcapillaries when viewed in cross section may be less than 20 percent area ("area%"), less than 15% area, less than 10% area, or less than 5% area of the total cross-sectional area of peelable polymeric coating. In such embodiments, the aggregate of space defined by the microcapillaries when viewed in cross section may be at least 0.05% area, at least 0.1% area, at least 0.5% area, at least 1% area area, or at least 2% area of the total cross-sectional area of removable polymeric coating.

[00116] As mentioned above, in various embodiments, microcapillaries can define individual and discrete voids. In such embodiments, the microcapillaries can be filled with a microcapillary fluid which is a gas at room temperature, such as air.

[00117] As mentioned above, in various embodiments, the microcapillaries may comprise an elastomeric polymer. In such embodiments, the elastomeric polymer has a lower flexural modulus than the polymeric matrix material, as described in more detail below. Suitable elastomers include any of those described above, but may be limited due to the type of polymeric matrix material selected. In various embodiments, the elastomeric polymer may be selected from the group consisting of an olefin elastomer, a silicone elastomer, a urethane elastomer, an amorphous rubber, and combinations of two or more thereof.

[00118] As previously noted, one or more embodiments of the present invention contemplate a removable polymeric coating with a relatively high modulus polymeric matrix material and a relatively low modulus polymeric microcapillary material, wherein the flexural modulus of the polymeric matrix material is high relative to polymeric microcapillary material, and the flexural modulus of polymeric microcapillary material is low relative to polymeric matrix material. Generally, high modulus polymer matrix material can have a flexural modulus of at least 300,000 psi, or in the range of 300,000 to 800,000 psi, 325,000 to 700,000 psi, or 330,000 to 600,000 psi. By way of example, a typical flexural modulus for poly(p-phenylene sulfide) ("PPS") is about 600,000 psi, for polyether ether ketone it is about 590,000 psi, for polycarbonate it is about of 345,000 psi, for polyethylene terephthalate it is about 400,000 psi, for polybutylene terephthalate it is about 330,000 psi, and for nylon 6/6 it is about 400,000 psi (all unfilled).

[00119] High modulus polymers are generally known as high performance polymers that exhibit high heat resistance (as measured by heat deflection temperature, for example), excellent mechanical properties, as well as abrasion properties and chemical resistance. They are, however, typically higher density polymers, with densities generally greater than 1.3 g/cm3. In various embodiments, the high modulus polymers of the polymeric matrix material can comprise polybutylene terephthalate ("PBT"), polyethylene terephthalate ("PET"), a polycarbonate, a polyamide (e.g., a nylon), polyether ether -ketone ("PEEK"), or combinations of two or more thereof. In one embodiment, the polymeric matrix material comprises PBT.

[00120] The low modulus polymeric microcapillary material may have a flexural modulus of less than 250,000 psi, or in the range of 100 to 250,000 psi, or 500 to 200,000 psi. By way of example, a typical high density polyethylene has a flexural modulus of about 200,000 psi, a typical low density polyethylene has a flexural modulus of about 30,000 psi, a typical thermoplastic polyurethane has a flexural modulus of about of 10,000 psi and a typical polyolefin elastomer (eg, ENGAGETM 8402) has a flexural modulus of about 580 psi.

[00121] Low modulus materials are generally characterized by high flexibility and excellent impact resistance even at low temperatures. These resins can have a melt index ranging from less than 1.0 to more than 1000 g/10 minutes as, for example, AFFINITYTM GA grades of olefin elastomer, commercially available from the Dow Chemical Company. These polyolefin elastomer resins can also have a density as low as 0.857 g/cm 3 and a melting point as low as 38°C such as ENGAGE™ 8842 also from The Dow Chemical Company.

[00122] In one or more embodiments, the polymeric microcapillary material may comprise any of the above-described ethylene-based polymers (e.g., HDPE, LDPE, EEA, EVA); olefin elastomers (as described above) and other ethylene copolymers, such as AFFINITYTM, ENGAGETM, and VERSIFYTM copolymers, commercially available from The Dow Chemical Company; olefin block copolymers (such as those commercially available under the tradename INFUSETM from The Dow Chemical Company, Midland, MI, USA), mesophase separated olefin multiblock interpolymers (as described in US Patent 7,947,793), olefin block composites (as described in US Patent Application Publication 2008/0269412, published October 30, 2008), or combinations of two or more thereof.

[00123] As mentioned above, in various embodiments, the microcapillaries may comprise a low viscosity filler material capable of being pumped into the microcapillaries. In other words, such a low viscosity filler material can be incorporated into the microcapillaries after the extrusion of the removable polymeric coating; such fillers need not be co-extruded with the polymeric matrix material. This is in contrast to polymeric materials such as elastomers discussed above.

[00124] Suitable low viscosity fillers include fluids with a wide viscosity range, as shown in Table 1. As used herein, "low viscosity" shall indicate liquid fillers (at 100°C) that have a kinematic viscosity at 100° C in the range of 1 to 45,000 centistokes ("cSt"). In various embodiments, the low viscosity filler material can have a viscosity at 100°C in the range of 4 to 30,000 cSt, 4 to 15,000 cSt, 4 to 2,000 cSt, 4 to 1,700 cSt, or 4 to 250 cSt. cSt. Specific examples of such materials include paraffinic oils such as SUNPARTM grades (available from Sunoco Corp.); vegetable oils such as soybean oil; poly-alpha-olefin ("PAO") fluids such as DURASYNTM grades (available from Ineos Corp.); and polybutenes such as INDOPOLTM grades (available from Ineos Corp.).

[00125] Other suitable materials are formulated composites, such as those typically used in filling and flooding telecommunications cables. An example of a filler compound used in snubber tube fiber optic telecommunication cables is a thixotropic gel, disclosed in US Patent 5,505,773 and composed of polybutylene, fumed silica and polyethylene wax. A typical flood compound is disclosed in US Patent 4,724,277 and is composed of a mixture of microcrystalline wax, a polyethylene and a rubber. Examples of such materials include those commercially available from Sonneborn LLC, Soltex Corp, H & R ChemPharm (UK) Ltd and MasterChem Solutions; as well as compounds based on high melt index polyolefin elastomers, such as those described in US Provisional Patent Applications 62/140,673 and 62/140,677. Some cable fill/flood compounds are designed with viscosity exhibiting shear thinning profiles to allow pumping at room temperature without the need for additional heating. Table 1 - Typical viscosities of suitable low viscosity materials [1] J. Sanders, Putting the Simple Back into Viscosity, White Paper, Lubrication Engineers Inc., 2011 [2] TW Ryan et al., The Effects of Vegetable Oil Properties on Injection and Combustion in Two Different Diesel Engines, Journal of the American Oil Chemists' Society 61, no. 10 (October 5): 1610-1619 [3] Noureddini H. et al., Viscosities of Vegetable Oils and Fatty Acids, Journal of the American Oil Chemists' Society 69, no. 12 (December 1): 1189-1191 [4] Indopol Polybutene Product Bulletin, Ineos Oligomers, Brochure No. PB1000, November 2009 [5] Sunoco Product Information, Sunpar Range, March 2013 [6] Telephone Flooding Compound FC 57 M, Product Data Sheet, Sonneborn Refined products, March 2012 [7] Cable Flooding Compounds (Soltex Flood 522), Soltex, March 2009

[00126] The microcapillaries in the peelable polymeric coatings can be longitudinally continuous (or substantially continuous) or non-continuous along the length of the polymeric coating. As used in this embodiment, the term "substantially continuous" means that the microcapillaries extend uninterruptedly for at least 90% of the length of the peelable polymeric coating. When longitudinally discontinuous, the microcapillaries can be of any desired length. In various embodiments, the longitudinally discontinuous microcapillaries can have an average length ranging from 1 to about 100 cm, from 1 to 50 cm, from 1 to 20 cm, from 1 to 10 cm, or from 1 to 5 cm.

[00127] In various embodiments, the peelable polymeric coatings may comprise external cues corresponding to the location of the microcapillaries. These external signs should allow a person working with the sheathed conductor to locate points on the sheath that allow the sheath to be detached. Incorporation of external indicia can be accomplished by any means known or discovered in the art. Examples of such indices include, but are not limited to, printing, engraving, coloring or embossing.

[00128] In one or more embodiments, the peelable polymeric coating may have a reduction in tensile strength of less than 50%, less than 45%, less than 40%, less than 35% or less than 30% compared to a coating identical prepared from the same polymeric matrix material, except without microcapillaries. Additionally, the peelable polymeric coating can have a reduction in tensile strength in the range of 10 to 50%, or 20 to 45% over an identical coating prepared from the same polymeric matrix material unless it lacks microcapillaries. .

[00129] In various embodiments, the peelable polymeric coating may have a reduction in elongation at break of less than 30%, or less than 25% compared to an identical coating prepared from the same polymeric matrix material unless it has no microcapillaries. The reduction in elongation-at-break is determined by calculating the difference in elongation-at-break between the reference coating and the peelable coating, dividing this difference by the elongation-at-breaking of the reference coating and multiplying by 100%. . For example, if a reference coating has an elongation-at-break of 900%, and a peelable coating has an elongation-at-break of 800%, the reduction in elongation at break is (100/900)*100%, or 11.1%. Additionally, the peelable polymeric coating can have a reduction in elongation-at-break in the range of 5 to 30%, or 10 to 25% over an identical coating prepared from the same polymeric matrix material unless otherwise have microcapillaries.

[00130] In various embodiments, the peelable polymeric coating can have a reduction in tear strength of at least 5%, at least 10%, at least 25%, at least 50% or at least 75% compared to an identical coating prepared from the same polymeric matrix material, except without microcapillaries. Furthermore, the peelable polymeric coating can have a reduction in tear strength of up to 90%, up to 85%, or up to 80% over an identical coating prepared from the same polymeric matrix material, except without microcapillaries.

[00131] The preparation of peelable coatings can be carried out by simple modifications of the sets of matrices described above to reduce the number of microcapillaries, as desired. Such modifications are well within the capabilities of a person of ordinary skill in the art.

TEST METHODS Density

[00132] Density is determined according to ASTM D 792.

Fusion Index

[00133] The melting index, or I2, is measured according to ASTM D 1238, condition 190°C/2.16 kg, and is presented in grams eluted for 10 minutes.

Tensile Strength and Elongation at Break

[00134] Measure tensile strength and elongation according to ASTM D 638 method.

Tear resistance

[00135] Tear strength is measured as follows: 5.0 inch long specimens are die cut from extruded tape samples and a 1.0 inch long slit is made in each specimen. The tear test is conducted on an Instron Model 4201 tester in the axial tape direction at a speed of 12"/min. Reported data are average values based on the measurement of five specimens.

MATERIALS

[00136] The following materials are used in the Examples below.

[00137] AXELERONTM GP C-0588 BK (“LDPE”) is a low density polyethylene with a density of 0.932 g/cm3, a melting index (I2) in the range of 0.2 to 0.4 g/10 min . and containing carbon black in an amount ranging from 2.35 to 2.85% by weight (ASTM D1603). AXELERONTM GP C-0588 BK is commercially available from The Dow Chemical Company, Midland, MI, USA.

[00138] AXELERONTM FO 6548 BK (“MDPE”) is a medium density polyethylene with a density of 0.944 g/cm3, a melting index (I2) in the range of 0.6 to 0.9 g/10 min. and containing carbon black in an amount ranging from 2.35 to 2.85% by weight (ASTM D1603). AXELERONTM FO 6548 BK is commercially available from The Dow Chemical Company, Midland, MI, USA.

[00139] ENGAGETM 8200 is an ethylene/octene polyolefin elastomer with a density of 0.870 g/cm3 and a melt index of 5.0 g/10 min., which is commercially available from The Dow Chemical Company, Midland, MI , USA.

EXAMPLES Sample Preparation Air-filled microcapillary samples

[00140] Prepare four samples (S1-S4) using a ribbon extrusion system consisting of a single screw extruder (Kilion 3.81 cm extruder) equipped with a microcapillary matrix capable of handling a polymer melt and an air stream, according to the schematic description of FIG. 1. The array to be used in these Examples is described in detail in PCT Published Patent Application WO 2014/003761, specifically with respect to Figures 4A and 4A1, and the corresponding wording of the written description, which is incorporated herein by reference. The matrix has 42 microcapillary nozzles, a width of 5 cm and a matrix gap of 1.5 mm. Each microcapillary nozzle has an outer diameter of 0.38 mm and an inner diameter of 0.19 mm. The plant air is supplied by an air line with a flowmeter, which is fully open before the machine warms up to avoid blockage of the microcapillary nozzles by the backflow of the polymer melt. In preparing the microcapillary sheets, first the extruder, gear pump, transfer lines and die are heated to operating temperatures with a "soak" time of about 30 minutes. Operating temperatures are shown in Table 2. As the polymer pellets pass through the extruder screw, the polymer becomes molten. The screw extruder feeds the polymer melt to the gear pump, which maintains a substantially constant flow of polymer mass towards the microcapillary matrix. The polymer melt then passes over the microcapillary nozzles and gathers streamlines of airflow, which maintain the size and shape of the microcapillary channels. On exiting the extrusion die, the extrudate is passed through a cooling roller. Once the extrudate is tempered, it is taken by a pressure roller. The airflow rate is carefully adjusted in such a way that the microcapillaries do not blow out, but maintain reasonable microcapillary dimensions. Line speed is controlled by a leveling roller on the roller stack. Sample compositions, their properties and other process parameters are provided in Table 3, below. Table 2 - Microcapillary Extrusion Line Temperature Profile for Air-Filled Microcapillary Sheets

[00141] The resulting tapes are approximately 1.6 inches wide and approximately 50 mils thick and have the following properties, shown in Table 3. Table 3 - Composition and Properties of Samples S1-S4

Comparative Samples and Elastomer-Filled Microcapillary Samples

[00142] Prepare a Sample (S5) and a Comparative Sample (CS1 and CS2) using a ribbon extrusion system consisting of two single-screw extruders (1.9 cm and 3.81 cm Killion extruder) equipped with a microcapillary matrix capable of handling two polymer melt streams. This line consists of a 3.81 cm Killion single screw extruder to deliver the polymer melt to the matrix material and a 1.9 cm Killion single screw extruder to deliver the polymer melt to the microcapillaries through from a transfer line to the microcapillary matrix. The array to be used in these Examples is described in detail in PCT Published Patent Application WO 2014/003761, specifically with reference to Figures 4A and 4A1, and the corresponding wording of the written description, which is incorporated herein by reference. The matrix has 42 microcapillary nozzles, a width of 5 cm and a matrix gap of 1.5 mm. Each microcapillary nozzle has an outer diameter of 0.38 mm and an inner diameter of 0.19 mm.

[00143] Sample S5 and Comparative Samples CS1 and CS2 are prepared as follows. First, the extruders, gear pump, transfer lines and die are heated to operating temperatures with a "soak" time of about 30 minutes. The temperature profiles for the Killion 3.81 cm and 1.9 cm single screw extruders are shown in Table 4 below. The microcapillary polymer resins are loaded into the hopper of the Killion 1.9 cm single screw extruder, and the screw speed is turned to the target value (30 rpm). As the polymer melt exits the microcapillary nozzles, the matrix polymer resins are filled into the hopper of a Killion 3.81 cm single screw extruder and the main extruder is turned on. The extruder screw of the Killion 3.81 cm single screw extruder feeds the melt to a gear pump, which maintains a substantially constant flow of melt towards the microcapillary matrix. Next, the polymer melt from the 3.81 cm Killion single screw extruder is divided into two streams that meet the polymer strands from microcapillary nozzles. Upon exiting the extrusion die, the extrudate is cooled on a cooling roller in a roller stack. Once the extrudate is tempered, it is taken by a pressure roller. Line speed is controlled by a leveling roller on the roller stack. Table 4 - Temperature profiles of Killion 3.81 cm and 1.9 cm single screw extruders.

[00144] The extrusion system is configured to provide two streams of polymer melt: a first polymer (Kilion extruder 3.81 cm) to form a continuous matrix surrounding a second polymer (Killion extruder 1.9 cm) formed as microcapillaries embedded in the first polymer. The first polymer (matrix) of S5 is MDPE, and the second polymer (microcapillary) of S5 is ENGAGETM 8200. For CS1, both the first and second polymers are MDPE. For CS2, both the first and second polymers are LDPE. Processing conditions and microcapillary size for S5, CS1 and CS2 are shown in Table 5 below. Estimated from density measurements, S5 contains 18 percent by weight of microcapillary material (ENGAGETM 8200). Table 5 - Processing conditions and microcapillary dimensions for S1 and CS1

Example

[00145] Analyze each of CS 1, CS2 and S1-S5 according to the Test Methods provided above. The results are provided in Table 6, below. Table 6 - CS1, CS2, and S1-S5 Properties

[00146] CS1 is a sample representing a solid tape made from commercial MDPE, which shows a tear strength of about 840 lb/in. and typical tensile and elongation properties for this compound. S1 and S2 show the same compound extruded into a ribbon with air-filled microcapillaries. When torn in the axial direction along one of the capillaries, the tear strength is shown to be reduced by 76 and 80%, respectively, depending on the size of the microcapillaries. S5 shows that a sample with microcapillaries filled with a polyolefin elastomer (ENGAGETM 8200) can also provide a significant reduction in tear strength (about 51%).

[00147] CS2 is a sample representing a solid tape made from commercial LDPE, which shows a tear strength of about 296 lb/in. and typical tensile and elongation properties for this compound. S3 and S4 are samples made using the LDPE composite with air-filled microcapillaries, showing tear strength reductions of about 57 and 72%, respectively, depending on the size of the microcapillaries.

[00148] It should be noted that all of the above inventive samples are made with 42 microcapillaries. Such a construction has an effect on the general elongation and tensile properties as shown by the data. As previously described, however, only a limited number (e.g., 2 to 4) of microcapillaries placed around the circumference of the liner would be needed to provide ease of tearing, while the rest of the liner can remain unchanged for maximum mechanical protection of the liner. cable. This would minimize the negative impact of microcapillaries on the overall mechanical properties of the coating.

Claims (17)

1. Clad conductor, characterized in that it comprises: (a) a conductor which is an optical cable or fiber; and (b) an annular microcapillary product which is a polymeric matrix material extruded over and completely surrounding the conductor, said peelable polymeric coating comprising a polymeric matrix material and in the range of 1 to 8 microcapillaries extending in the direction of the conductor. elongation of said peelable polymeric coating, said microcapillaries defining individual, discrete voids, and said microcapillaries being completely surrounded by the polymeric matrix material. 2. Coated conductor, according to claim 1, characterized in that said microcapillaries contain air within one or more of said empty spaces. 3. Coated conductor, according to claim 1, characterized in that an aggregate of the space defined by said microcapillaries when viewed as a cross section of the peelable polymeric coating taken orthogonal to the direction of elongation of said microcapillaries constitutes less than 20% of area of the total area of said peelable polymeric coating cross-section. 4. Coated conductor, according to claim 1, characterized in that said microcapillaries have an average diameter in the range of 0.5 μm to 2,000 μm, and said microcapillaries have a cross-sectional shape selected from the group consisting in circular, rectangular, oval, star-shaped, diamond, triangular, square, pentagonal, hexagonal, octagonal, curvilinear and combinations thereof, wherein said peelable polymeric coating has a thickness in the range of 10 to 180 mils. 5. Coated conductor, according to claim 1, characterized in that the ratio of the thickness of said peelable polymeric coating to the average diameter of said microcapillaries is in the range of 2:1 to 400:1. 6. Coated conductor, according to claim 1, characterized in that said peelable polymeric coating has a reduction in tensile strength of less than 50% compared to an identical coating prepared from the same matrix material, except that does not have microcapillaries, said peelable polymeric coating having an elongation-at-break reduction of less than 30% compared to an identical coating prepared from the same matrix material, except that it does not have microcapillaries. 7. Coated conductor, according to claim 1, characterized in that said polymeric matrix material comprises an ethylene-based polymer. 8. Coated conductor, according to claim 1, characterized in that said peelable polymeric coating comprises external indications corresponding to the internal location of said microcapillaries. 9. Coated conductor, according to claim 1, characterized in that said microcapillaries are longitudinally continuous along the length of said peelable polymeric coating. 10. Coated conductor, according to claim 1, characterized in that said microcapillaries are longitudinally discontinuous along the length of said peelable polymeric coating. 11. Coated conductor, according to claim 1, characterized in that said discrete individual voids consist of air. 12. Coated conductor, according to claim 1, characterized in that said discrete individual voids consist of gas. 13. Coated conductor, according to claim 1, characterized in that the conductor has an elongation direction; and the microcapillaries extend in the same direction of elongation as the conductor. 14. Coated conductor, according to claim 13, characterized in that each discrete empty space consists of gas. 15. Coated conductor, according to claim 13, characterized in that each discrete void consists of air. 16. Coated conductor, according to claim 13, characterized in that each microcapillary is continuous along the length of the peelable polymeric coating. 17. Coated conductor, according to claim 13, characterized in that each microcapillary is longitudinally discontinuous along the length of the peelable polymeric coating.