Coated substrates and optical fibers formed therefrom

Abstract

Embodiments of the present disclosure are directed to coated substrates including a water swellable coating applied to a substrate. The water swellable coating includes, based on a total weight of the water swellable coating, 30 wt. % to 90 wt. % of a plastisol binder and 10 wt. % to 70 wt. % of a superabsorbent polymer. The plastisol binder includes, based on the total weight of the plastisol binder, 1 wt. % to 50 wt. % of water soluble polymer and 50% to 99 wt. % plasticizer.

Description

CLAIM OF PRIORITY

[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 63 / 436,094 bearing Attorney Docket Number 1202225 and filed on Dec. 29, 2022, which is hereby incorporated by reference in its entirety.TECHNICAL FIELD

[0002] Embodiments of the present disclosure are generally related to coated substrates with water swellable coatings thereon having an advantageous water absorption capacity.BACKGROUND

[0003] Water swellable substrates, such as yarns and tapes, are used in outdoor or water-vulnerable cable applications to prevent water ingress. Conventional water swellable substrates are made with superabsorbent polymers bonded to yarns with a water insoluble or a water soluble binder. However, water insoluble binders may isolate some of the superabsorbent polymer and may be slow to absorb ingressing water, which may decrease the yarn's water blocking efficiency. While water soluble binders may absorb ingressing water faster than a water insoluble binder, water soluble binders may be slow to dissolve and expose the superabsorbent polymer to water and may not provide any appreciable advantage over their insoluble counterparts.

[0004] Accordingly, a continual need exists for improved water swellable substrates with increased water absorption capacity and improved resistance to water ingress for the abovementioned applications.SUMMARY

[0005] Embodiments of the present disclosure are directed to coated substrates comprising a water swellable coating including a plastisol binder and a superabsorbent polymer.

[0006] According to one embodiment, a coated substrate is provided. The coated substrate comprises a water swellable coating applied to a substrate. The water swellable coating comprises, based on a total weight of the water swellable coating, 30 wt. % to 90 wt. % of a plastisol binder and 10 wt. % to 70 wt. % of a superabsorbent polymer. The plastisol binder comprises, based on a total weight of the plastisol binder, 1 wt. % to 50 wt. % of water soluble polymer and 50% to 99 wt. % plasticizer.

[0007] Additional features and advantages of the embodiments described herein will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description, which follows and the claims.DRAWINGS

[0008] FIG. 1 is a schematic cross sectional view of a coated substrate, according to one or more embodiments described herein;

[0009] FIG. 2 is a perspective view of a cable, according to one or more embodiments described herein;

[0010] FIG. 3 is a schematic cross sectional view of another cable, according to one or more embodiments described herein;

[0011] FIG. 4 is a schematic cross sectional view of another cable, according to one or more embodiments described herein; and

[0012] FIG. 5 is a schematic cross sectional view of another cable, according to one or more embodiments described herein.DETAILED DESCRIPTION

[0013] Reference will now be made in detail to various embodiments of coated substrates, specifically coated substrates comprising a water swellable coating. The water swellable coating comprises, based on a total weight of the water swellable coating, 30 wt. % to 90 wt. % of a plastisol binder and 10 wt. % to 70 wt. % of a superabsorbent polymer. The plastisol binder comprises, based on the total weight of the plastisol binder, 1 wt. % to 50 wt. % of water soluble polymer and 50% to 99 wt. % plasticizer. In embodiments, the coated substrates may have an advantageous water absorption capacity. The water swellable coating may be sued in coatings to provide an advantageous resistance to water ingress.

[0014] The disclosure should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the subject matter to those skilled in the art.Definitions

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in the disclosure herein is for describing particular embodiments only and is not intended to be limiting.

[0016] Approximating language, as used herein throughout the specification and claims, is applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about”, “approximately”, and “substantially”, are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value, or the precision of the methods or machines for constructing or manufacturing the components and / or systems. For example, the approximating language may refer to being within a ten percent margin.

[0017] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order, nor that with any apparatus specific orientations be required. Accordingly, where a method claim does not actually recite an order to be followed by its steps, or that any apparatus claim does not actually recite an order or orientation to individual components, or it is not otherwise specifically stated in the claims or description that the steps are to be limited to a specific order, or that a specific order or orientation to components of an apparatus is not recited, it is in no way intended that an order or orientation be inferred, in any respect. This holds for any possible non-express basis for interpretation, including: matters of logic with respect to arrangement of steps, operational flow, order of components, or orientation of components; plain meaning derived from grammatical organization or punctuation, and; the number or type of embodiments described in the specification.

[0018] As used in the specification and the appended claims, the singular forms “a,”“an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Thus, for example, reference to “a” component includes aspects having two or more such components, unless the context clearly indicates otherwise.

[0019] The term “wt. %,” as described herein, refers to the weight fraction of the individual component based on a total weight of the water swellable coating or the plastisol binder, as indicated, unless otherwise noted.

[0020] The terms “water soluble,”“dissolvable” or “dissolve,” as described herein, refer to least 1 gram of material being dissolvable for every 30 grams of deionized water at standard temperature (20° C.) and pressure (1 atm) on visual inspection.

[0021] The term “plastisol,” as described herein, refers to formulations comprising polymer particles suspended in liquid plasticizer. When sufficiently heated, the polymer particles absorb the plasticizer causing the polymer particles to fuse together to form a gel resulting in permanently plasticized solid product.

[0022] The term “plasticizer,” as described herein, refers to a molecule or substance added to a composition to promote a composition's plasticity and flexibility.

[0023] The term “gelation temperature,” as described herein, refers to the temperature at which the peak viscosity is measured using a Rheometric Dynamic Analyzer (RDA) from BASF.

[0024] The term “water absorption capacity,” as described herein, refers to the amount of water a solid material can absorb and can be expressed in terms of the mass of water absorption per the mass of the solid material. For example, a solid material's water absorption capacity may be expressed by the grams of distilled water absorbed per gram of solid material (e.g., gram / gram). To measure the water absorption capacity, a prescribed mass of water absorbent material is obtained, and 100 grams of water is added to the water absorbent material. The material is stirred for two minutes in the water to break up any agglomerates. The water absorbent material is left to sit in water for an additional ten minutes. The swollen water absorbent material is poured into a funnel lined with a paper coffee filter to drain excess water into a container. The mass of excess water is measured after fifteen minutes. The water absorption capacity is calculated by subtracting the mass of excess water from 100 grams of water. The resulting amount of water is then divided by the prescribed mass of the absorbent material.

[0025] The terms “plastisol binder,”“plastisol,” or “binder,” as described herein, refer to formulations comprising water soluble polymer suspended in a plasticizer. Plastisol formulations may comprise other ingredients and are contemplated in this present disclosure.

[0026] The term “initial water ingress,” as described herein, refers to a measurement of the ingression of water into the coated substrate after 1 minute as tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

[0027] The terms “water ingress after 24 hours” and “24-hour water ingress,” as described herein refers to a measurement of the ingression of water into the coated substrate after 24 hours as tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

[0028] The term “dry cable,” as described herein, refers to the use of superabsorbent polymer to absorb and block the ingress of water in a cable. Optical fibers are not contaminated with a gel or other compound and thus do not require labor intensive cleaning. The term “dry cable” distinguishes the design from a conventionally filled cable that relies on water blocking compounds or gels to prevent the ingress of water.

[0029] The term “coating weight,” as described herein, refers to the amount of water swellable coating applied to a given substrate, based on a total weight of the coated substrate.

[0030] As discussed hereinabove, water swellable substrates, such as yarns, are used in outdoor or water-vulnerable cable applications to prevent water ingress. Conventional water swellable substrates are made with superabsorbent polymers bonded to yarns with a water insoluble or a water soluble binder. However, water insoluble binders may isolate some of the superabsorbent polymer and may be slow to absorb ingressing water, which may decrease the yarn's water blocking efficiency. While water soluble binders may absorb ingressing water faster than a water insoluble binder, water soluble binders may be slow to dissolve and expose the superabsorbent polymer to water and may not provide any appreciable advantage over their insoluble counterparts.

[0031] Disclosed herein are coated substrates, which mitigate one or more of the aforementioned problems. Specifically, the coated substrates disclosed herein comprise a water swellable coating applied to a substrate. The water swellable coating comprises a plastisol binder and a superabsorbent polymer. The plastisol binder comprises a water soluble polymer, which dissolves quickly in in water to expose the superabsorbent polymer to absorb water. The dissolved water soluble polymer increases the viscosity of the ingressing water which further improves water blocking efficiency.Water Swellable Coating

[0032] The water swellable coating disclosed herein may generally be described as comprising a superabsorbent polymer (SAP) and a plastisol binder.Superabsorbent Polymer

[0033] Generally, an SAP is a water-absorbing hydrophilic compound that may absorb and retain substantially large amounts of a liquid relative to its own mass. SAPs may be used for blocking water penetration in underground power or communications cable, in self-sealing concrete, horticultural water retention agents, and control of spill and waste aqueous fluid, among other applications.

[0034] While not wishing to be bound by theory, the SAPs are typically prepared from polymers that have ions along one or more chains in the polymer structure. Thus, water enters the selected SAP to solvate the ionic group, which in turn may create higher osmotic pressure. This may result in a higher water absorption capacity because water swells the polymer network to keep the ion concentration balanced between the polymer and the water. In embodiments, the SAP may comprise salts of polyacrylate-based polymer, polyacrylamide-based polymer, or combinations thereof. In embodiments, the salt of polyacrylate-based polymer may comprise sodium polyacrylate-based polymers, potassium polyacrylate-based polymers, ammonium polyacrylate-based polymers, or combinations thereof.

[0035] The water swellable coating may comprise a minimum amount of SAP (e.g., greater than or equal to 10 wt. %) to ensure the desired water absorption capacity is achieved. The amount of SAP in the water swellable coating may be minimized (e.g., less than or equal to 70 wt. %) to ensure that a liquid property is present in the water swellable coating. Accordingly, in embodiments, the water swellable coating may comprise, based on a total weight of the water swellable coating, 10 wt. % to 70 wt. % SAP. In embodiments, the amount of SAP in the water swellable coating may be, based on the total weight of the water swellable coating, greater than or equal to 10 wt. %, greater than or equal to 15 wt. %, greater than or equal to 20 wt. %, greater than or equal to 25 wt. %, or even greater than or equal to 30 wt. %. In embodiments, the amount of SAP in the water swellable coating may be, based on the total weight of the water swellable coating, less than or equal to 70 wt. %, less than or equal to 65 wt. %, less than or equal to 60 wt. %, less than or equal to 55 wt. %, less than or equal to 50 wt. %, less than or equal to 45 wt. %, less than or equal to 40 wt. %, or even less than or equal to 35 wt. %. In embodiments, the amount of SAP in the water swellable coating may be, based on the total weight of the water swellable coating, from 10 wt. % to 70 wt. %, from 10 wt. % to 65 wt. %, from 10 wt. % to 60 wt. %, from 10 wt. % to 55 wt. %, from 10 wt. % to 50 wt. %, from 10 wt. % to 45 wt. %, from 10 wt. % to 40 wt. %, from 10 wt. % to 35 wt. %, from 15 wt. % to 70 wt. %, from 15 wt. % to 65 wt. %, from 15 wt. % to 60 wt. %, from 15 wt. % to 55 wt. %, from 15 wt. % to 50 wt. %, from 15 wt. % to 45 wt. %, from 15 wt. % to 40 wt. %, from 15 wt. % to 35 wt. %, from 20 wt. % to 70 wt. %, from 20 wt. % to 65 wt. %, from 20 wt. % to 60 wt. %, from 20 wt. % to 55 wt. %, from 20 wt. % to 50 wt. %, from 20 wt. % to 45 wt. %, from 20 wt. % to 40 wt. %, from 20 wt. % to 35 wt. %, from 25 wt. % to 70 wt. %, from 25 wt. % to 65 wt. %, from 25 wt. % to 60 wt. %, from 25 wt. % to 55 wt. %, from 25 wt. % to 50 wt. %, from 25 wt. % to 45 wt. %, from 25 wt. % to 40 wt. %, from 25 wt. % to 35 wt. %, from 30 wt. % to 70 wt. %, from 30 wt. % to 65 wt. %, from 30 wt. % to 60 wt. %, from 30 wt. % to 55 wt. %, from 30 wt. % to 50 wt. %, from 30 wt. % to 45 wt. %, from 30 wt. % to 40 wt. %, or even from 30 wt. % to 35 wt. %, or any and all subranges formed from any of these endpoints.

[0036] In embodiments, the SAP may have a water absorption capacity of 10 gram / gram to 1000 gram / gram. In embodiments, the SAP may have a water absorption capacity of greater than or equal to 10 gram / gram, greater than or equal to 50 gram / gram, greater than or equal to 100 gram / gram, greater than or equal to 150 gram / gram, greater than or equal to 200 gram / gram, greater than or equal to 250 gram / gram, greater than or equal to 300 gram / gram, or even greater than or equal to 350 gram / gram. In embodiments, the SAP may have a water absorption capacity of less than or equal to 1000 gram / gram, less than or equal to 950 gram / gram, less than or equal to 900 gram / gram, less than or equal to 850 gram / gram, less than or equal to 800 gram / gram, less than or equal to 750 gram / gram, less than or equal to 700 gram / gram, less than or equal to 650 gram / gram, less than or equal to 600 gram / gram, less than or equal to 550 gram / gram, or even less than or equal to 500 gram / gram. In embodiments, the SAP may have a water absorption capacity of from 10 gram / gram to 1000 gram / gram, from 10 gram / gram to 950 gram / gram, from 10 gram / gram to 900 gram / gram, from 10 gram / gram to 850 gram / gram, from 10 gram / gram to 800 gram / gram, from 10 gram / gram to 750 gram / gram, from 10 gram / gram to 700 gram / gram, from 10 gram / gram to 650 gram / gram, from 10 gram / gram to 600 gram / gram, from 10 gram / gram to 550 gram / gram, from 10 gram / gram to 500 gram / gram, from 100 gram / gram to 1000 gram / gram, from 100 gram / gram to 950 gram / gram, from 100 gram / gram to 900 gram / gram, from 100 gram / gram to 850 gram / gram, from 100 gram / gram to 800 gram / gram, from 100 gram / gram to 750 gram / gram, from 100 gram / gram to 700 gram / gram, from 100 gram / gram to 650 gram / gram, from 100 gram / gram to 600 gram / gram, from 100 gram / gram to 550 gram / gram, from 100 gram / gram to 500 gram / gram, from 200 gram / gram to 1000 gram / gram, from 200 gram / gram to 950 gram / gram, from 200 gram / gram to 900 gram / gram, from 200 gram / gram to 850 gram / gram, from 200 gram / gram to 800 gram / gram, from 200 gram / gram to 750 gram / gram, from 200 gram / gram to 700 gram / gram, from 200 gram / gram to 650 gram / gram, from 200 gram / gram to 600 gram / gram, from 200 gram / gram to 550 gram / gram, from 200 gram / gram to 500 gram / gram, from 350 gram / gram to 1000 gram / gram, from 350 gram / gram to 950 gram / gram, from 350 gram / gram to 900 gram / gram, from 350 gram / gram to 850 gram / gram, from 350 gram / gram to 800 gram / gram, from 350 gram / gram to 750 gram / gram, from 350 gram / gram to 700 gram / gram, from 350 gram / gram to 650 gram / gram, from 350 gram / gram to 600 gram / gram, from 350 gram / gram to 550 gram / gram, or even from 350 gram / gram to 500 gram / gram, or any and all subranges formed from any of these endpoints.

[0037] In embodiments, the SAP included in the water swellable coating may comprise a SAP powder. In these or other embodiment, the water swellable coating may include particles of the SAP powder dispersed in the water swellable coating.

[0038] Suitable commercial embodiments of the water soluble polymer particles are available from Stewart Superabsorbents, such as a sodium polyacrylate polymer MAX 400-53; or available from Sumitomo Seika, such as sodium polyacrylate polymer AQUAKEEP 10SF SAP.Plastisol Binder

[0039] In embodiments, the water swellable coating may comprise, based on a total weight of the water swellable coating, 30 wt. % to 90 wt. % of a plastisol binder. In embodiments, the amount of plastisol binder in the water swellable coating may be, based on a total weight of the water swellable coating, greater than or equal to 30 wt. %, greater than or equal to 35 wt %, greater than or equal to 40 wt. %, greater than or equal to 45 wt. %, greater than or equal to 50 wt. %, greater than or equal to 55 wt. %, greater than or equal to 60 wt. %, or even greater than or equal to 65 wt. %. In embodiments, the amount of plastisol binder in the water swellable coating may be, based on a total weight of the water swellable coating, less than or equal to 90 wt. %, less than or equal to 85 wt. %, less than or equal to 80 wt. %, less than or equal to 75 wt. %, or even less than or equal to 70 wt. %. In embodiments, the amount of plastisol binder in the water swellable coating may be, based on a total weight of the water swellable coating, from 30 wt. % to 90 wt. %, from 30 wt. % to 85 wt. %, from 30 wt. % to 80 wt. %, from 30 wt. % to 75 wt. %, from 30 wt. % to 70 wt. %, from 35 wt. % to 90 wt. %, from 35 wt. % to 85 wt. %, from 35 wt. % to 80 wt. %, from 35 wt. % to 75 wt. %, from 35 wt. % to 70 wt. %, from 40 wt. % to 90 wt. %, from 40 wt. % to 85 wt. %, from 40 wt. % to 80 wt. %, from 40 wt. % to 75 wt. %, from 40 wt. % to 70 wt. %, from 45 wt. % to 90 wt. %, from 45 wt. % to 85 wt. %, from 45 wt. % to 80 wt. %, from 45 wt. % to 75 wt. %, from 45 wt. % to 70 wt. %, from 50 wt. % to 90 wt. %, from 50 wt. % to 85 wt. %, from 50 wt. % to 80 wt. %, from 50 wt. % to 75 wt. %, from 50 wt. % to 70 wt. %, from 55 wt. % to 90 wt. %, from 55 wt. % to 85 wt. %, from 55 wt. % to 80 wt. %, from 55 wt. % to 75 wt. %, from 55 wt. % to 70 wt. %, from 60 wt. % to 90 wt. %, from 60 wt. % to 85 wt. %, from 60 wt. % to 80 wt. %, from 60 wt. % to 75 wt. %, from 60 wt. % to 70 wt. %, from 65 wt. % to 90 wt. %, from 65 wt. % to 85 wt. %, from 65 wt. % to 80 wt. %, from 65 wt. % to 75 wt. %, or even from 65 wt. % to 70 wt. %, or any and all subranges formed from any of these endpoints.

[0040] The plastisol binders disclosed herein comprise water soluble polymer and plasticizer. When certain water soluble polymers and plasticizers are combined and heated to its gelation temperature as described below, the resulting plastisol binder may solidify into a non-flowable, but semi-flexible mass upon cooling.Water Soluble Polymer

[0041] Water soluble polymers provide the ability for the resulting plastisol binder to dissolve, disperse, or swell in water. In embodiments, the water soluble polymer included in the plastisol binders disclosed herein may comprise natural or synthetic polymers.

[0042] In embodiments, the water soluble polymer may be selected from the group consisting of polysaccharides, polypeptides, and combinations thereof. In one embodiment, the water soluble polymer may comprise hydroxypropyl methyl cellulose (HPMC). Water soluble polymer selected from this group may be desirable in food or medical grade applications.

[0043] In other embodiments, the water soluble polymer may comprise a synthetic water soluble polymer. In other embodiments, the water soluble polymer may be selected from the group consisting of polyvinyl alcohols, polyacrylic acid copolymer, poly(2-ethyl-2-oxazoline), polyvinylpyrrolidone, and combinations thereof.

[0044] The ability of the water soluble polymer particles to dissolve may be effected by the pH level of liquid being used to dissolve the plasticized film or article (e.g., water). For example, some water soluble polymers may have relatively poor solubility in neutral or acidic conditions. The liquid plastisol compositions disclosed herein may be adjusted to account for the pH level of the dissolving liquid. In embodiments, a buffer may be employed in the liquid plastisol composition to provide a suitable pH level for the water soluble polymers of the plasticized film or article to dissolve in water. In embodiments, an acid may be employed in the liquid plastisol composition to provide a suitable pH level for the water soluble polymers of the plasticized film or article to dissolve in water. In embodiments, a base may be employed in the liquid plastisol composition to provide a suitable pH level for the water soluble polymers of the plasticized film or article to dissolve in water.

[0045] The plastisol binder may comprise a minimum amount of water soluble polymer (e.g., greater than or equal to 1 wt. %) to ensure a desired form (e.g., coating) article) is achieved upon cooling. The amount of water soluble polymer in the plastisol binder may be limited (e.g., less than or equal to 50 wt. %) to ensure that the desired viscosity is achieved for processing purposes (e.g., coating a substrate). Accordingly, in embodiments, the amount of the water soluble polymer in the plastisol binder may be, based on the total weight of the plastisol binder, 1 wt. % to 50 wt. %. In embodiments, the amount of the water soluble polymer in the plastisol binder may be, based on the total weight of the plastisol binder, greater than or equal to 1 wt. % or even greater than or equal to 5 wt. %. In embodiments, the amount of the water soluble polymer in the plastisol binder may be, based on the total weight of the plastisol binder, less than or equal to 50 wt. %, less than or equal to 40 wt. %, less than or equal to 30 wt. %, less than or equal to 20 wt. %, or even less than or equal to 10 wt. %. In embodiments, the amount of the water soluble polymer in the plastisol binder may be, based on the total weight of the plastisol binder, from 1 wt. % to 50 wt. %, from 1 wt. % to 40 wt. %, from 1 wt. % to 30 wt. %, from 1 wt. % to 20 wt. %, from 1 wt. % to 10 wt. %, from 5 wt. % to 50 wt. %, from 5 wt. % to 40 wt. %, from 5 wt. % to 30 wt. %, from 5 wt. % to 20 wt. %, or even from 5 wt. % to 10 wt. %, or any and all subranges formed from any of these endpoints.

[0046] Water soluble polymer particles with a small average particle size may be used to ensure that the water soluble polymer particles form an article or film where the water soluble polymer particles have fully absorbed the plasticizer to form a consistent gel. In embodiments, the water soluble polymer may be provided in powder form. In embodiments, the water soluble polymer may be milled to produce a desired average particle size. In embodiments, the water soluble polymer may have a minimum average particle size (e.g., greater than or equal to 1 micron) to ensure that the water soluble polymer does not agglomerate and is not too fine to handle. The average particle size of the water soluble polymer may be limited (e.g., less than or equal to 500 microns) to ensure that the water soluble polymer may be fully infused and gel to form a consistent coating. Accordingly, in embodiments, the average particle size of the water soluble polymer in the plastisol binder may be 1 micron to 500 microns. In embodiments, the average particle size of the water soluble polymer particles in the plastisol binder may be greater than or equal to 1 micron, greater than or equal to 50 microns or even greater than or equal to 100 microns. In embodiments, the average particle size of the water soluble polymer in the plastisol binder may be less than or equal to 500 microns, less than or equal to 450 microns, less than or equal to 400 microns, less than or equal to 350 microns, less than or equal to 300 microns, or even less than or equal to 250 microns. In embodiments the average particle size of the water soluble polymer in the plastisol binder may be from 1 micron to 500 microns, from 1 micron to 450 microns, from 1 micron to 400 microns, from 1 micron to 350 microns, from 1 micron to 300 microns, from 1 micron to 250 microns, 50 micron to 500 microns, from 50 micron to 450 microns, from 50 micron to 400 microns, from 50 micron to 350 microns, from 50 micron to 300 microns, from 50 micron to 250 microns, 100 micron to 500 microns, from 100 micron to 450 microns, from 100 micron to 400 microns, from 100 micron to 350 microns, from 100 micron to 300 microns, or even from 100 micron to 250 microns, or any and all subranges formed from any of these end points.

[0047] Suitable commercial embodiments of the water soluble polymer are available from the POVAL brand from Kuraray, such as poly(vinyl alcohol) grade 49-88 S2 and under the METHOCEL brand from DuPont.Plasticizer

[0048] Suitable plasticizers for use in the liquid plastisol compositions of the present disclosure include those plasticizer that form a liquid dispersion or slurry when combined with the water soluble polymer particles. Upon sufficient heating, the water soluble polymer particles in the liquid plastisol composition absorb the plasticizer, causing the water soluble polymer particles to swell and fuse together forming gel. The resultant product is a permanently plasticized solid product.

[0049] In embodiments, the plasticizer may comprise a polyol. In embodiments, the polyol may be a diol. In other embodiments, the polyol may be a triol. In still other embodiments, the polyols may include 4, 5, or more than 6 hydroxyl groups. In embodiments, a polyols may be selected that exhibits similar polarity to the water soluble polymer particle chosen. Plasticizers selected from this group may also be advantageous in applications involving short-life applications such as food packaging. In embodiments, the plasticizer may be selected from the group consisting of glycols, sugar alcohols, sugars, glycerol, triacetin, propylene carbonate, fatty acids, urea, and combinations thereof. Exemplarily glycols include propylene glycol and poly(ethylene) glycols (“PEG”). Suitable poly(ethylene) glycols should be liquids at 22° C. (e.g., PEGs with a MW of 600 g / mol or less). In embodiments, the poly(ethylene) glycol may have a MW in the range of 100 g / mol to 600 g / mol, 200 g / mol to 550 g / mol, or 300 g / mol to 500 g / mol,

[0050] In embodiments, a minimum amount of plasticizer may be included in the plastisol binder (e.g., greater than or equal to 50 wt. %) to ensure a liquid property is present in the binder. The amount of plasticizer in the plastisol binder may be limited (e.g., less than or equal to 97 wt. %) to ensure that a consistent coating may be formed. Accordingly, in embodiments, the plastisol binder may comprise, based on a total weight of the plastisol binder, 50 wt. % to 99 wt. % plasticizer. In embodiments, the amount of plasticizer in the plastisol binder may be, based on the total weight of the plastisol binder, greater than or equal to 50 wt. %, greater than or equal to 55 wt. %, greater than or equal to 60 wt. %, greater than or equal to 65 wt. %, greater than or equal to 70 wt. %, greater than or equal to 75 wt. %, greater than or equal to 80 wt. %, greater than or equal to 85 wt. %, or even greater than or equal to 90 wt. %. In embodiments, the amount of plasticizer in the plastisol binder may be, based on the total weight of the plastisol binder, less than or equal to 99 wt. %, less than or equal to 95 wt. %, less than or equal to 90 wt. %, less than or equal to 85 wt. %, less than or equal to 80 wt. %, less than or equal to 75 wt. %, or even less than or equal to 70 wt. %. In embodiments, the amount of plasticizer in the plastisol binder may be, based on the total weight of the plastisol binder, from 50 wt. % to 99 wt. %, from 50 wt. % to 95 wt. %, from 50 wt. % to 90 wt. %, from 50 wt. % to 85 wt. %, from 50 wt. % to 80 wt. %, from 50 wt. % to 75 wt. %, from 50 wt. % to 70 wt. %, from 55 wt. % to 99 wt. %, from 55 wt. % to 95 wt. %, from 55 wt. % to 90 wt. %, from 55 wt. % to 85 wt. %, from 55 wt. % to 80 wt. %, from 55 wt. % to 75 wt. %, from 55 wt. % to 70 wt. %, from 60 wt. % to 99 wt. %, from 60 wt. % to 95 wt. %, from 60 wt. % to 90 wt. %, from 60 wt. % to 85 wt. %, from 60 wt. % to 80 wt. %, from 60 wt. % to 75 wt. %, from 60 wt. % to 70 wt. %, from 65 wt. % to 99 wt. %, from 65 wt. % to 95 wt. %, from 65 wt. % to 90 wt. %, from 65 wt. % to 85 wt. %, from 65 wt. % to 80 wt. %, from 65 wt. % to 75 wt. %, 65 wt. % to 70 wt. %, from 70 wt. % to 99 wt. %, from 70 wt. % to 95 wt. %, from 70 wt. % to 90 wt. %, from 70 wt. % to 85 wt. %, from 70 wt. % to 80 wt. %, from 70 wt. % to 75 wt. %, from 75 wt. % to 99 wt. %, from 75 wt. % to 95 wt. %, from 75 wt. % to 90 wt. %, from 75 wt. % to 85 wt. %, from 75 wt. % to 80 wt. %, from 80 wt. % to 99 wt. %, from 80 wt. % to 95 wt. %, from 80 wt. % to 90 wt. %, from 80 wt. % to 85 wt. %, from 85 wt. % to 99 wt. %, from 85 wt. % to 95 wt. %, from 85 wt. % to 90 wt. %, from 90 wt. % to 99 wt. %, or even from 90 wt. % to 95 wt. %, or any and all subranges formed from any of these endpoints.

[0051] Suitable commercial embodiments of plasticizer are available from Nature's Oil, such as propylene glycol, in USP grade.Additives

[0052] The plastisol binder may further include additives selected from the group consisting of viscosity modifiers, viscosity stabilizers, heat stabilizers, UV stabilizer, dyes, pigments, preservatives, fillers, adhesion promoters, and lubricants, and combinations thereof. These additives may be selected based on their tailored ability to improve an aspect of the water-swellable coating for ease of processing, performance, or service life.

[0053] In embodiments, the amount of the additives in the plastisol binder may be, based on the total weight of the plastisol binder, from 1 wt. % to 20 wt. %. In embodiments, the amount of the additives in the plastisol binder may be, based on the total weight of the plastisol binder, greater than or equal to 1 wt. %, greater than or equal to 3 wt. %, or even greater than or equal to 5 wt. %. In embodiments, the amount of the additives in the plastisol binder may be, based on the total weight of the plastisol binder, less than or equal to 20 wt. %, less than or equal to 15 wt. %, or even less than or equal to 10 wt. %. In embodiments, the amount of the additives in the plastisol binder may be, based on the total weight of the plastisol binder, from 1 wt. % to 20 wt. %, from 1 wt. % to 15 wt. %, from 1 wt. % to 10 wt. %, from 3 wt. % to 20 wt. %, from 3 wt. % to 15 wt. %, from 3 wt. % to 10 wt. %, from 5 wt. % to 20 wt. %, from 5 wt. % to 15 wt. %, or even from 5 wt. % to 10 wt. %, or any and all subranges formed from any of these endpoints.

[0054] Advantageously, the plastisol binder may be prepared without the need for water. In embodiments, the plastisol binder may be essentially water free. In embodiments, the plastisol binder may be, based on a total weight of the plastisol binder, less than 5 wt. %, less than 3 wt. %, less than 1 wt. %, less than 0.5 wt. %, or less than 0.1 wt. % water.Substrate

[0055] In embodiments of the coated substrate of the present disclosure, the substrate may comprise a yarn, fabric, textile, non-woven, paper, sheet, net, or scrim. In embodiments, the substrate may consist of fibers of polyamide, aramid or copolymers thereof, cellulose regenerated fibers, polyester, polyolefin, polyacrylic, polybenzoxazole, liquid crystalline polymer, fiberglass, basalt, rock wool, ceramic, metal, carbon, plant based fibers (e.g. cotton, hemp, jute), animal based fibers (e.g. wool, silk), or combinations thereof.

[0056] In embodiments of the coated substrate of the present disclosure, the substrate may comprise a continuous fiber reinforcement. A continuous fiber reinforcement, which may also be referred to as a continuous fiber tape, comprises a matrix material and a plurality of unidirectional continuous fibers embedded in the thermoplastic matrix. Suitable fibers include glass fibers, aramid fibers, basal fibers, carbon fibers, or a combination thereof. Suitable matrix include thermoplastic polymers or blends of two or more thernmoplastic polymers.

[0057] Referring now to FIG. 1, a coated substrate 100 is shown. The coated substrate 100 includes a water swellable coating 102 as described herein applied to a substrate 104 as described herein. The water swellable coating 102 may be applied to the substrate 104 via screen printing, roll coating, spray coating, slot die coating, dip molding, dip coating, spin coating, rotomolding, slush casting, injection molding, or extruding. When applied, the water swellable coating 102 may be in a slurry form as described below.

[0058] After application, the coated substrate 100 may be heated to a gelation temperature to convert the water swellable coating 102 from a slurry to a gelled plastisol. In embodiments, the gelation temperature may be in the range from 90° C. to 170° C., from 90° C. to 155° C., from 90° C. to 140° C., 105° C. to 170° C., from 105° C. to 155° C., from 105° C. to 140° C., from 120° C. to 170° C., from 120° C. to 155° C., or even from 120° C. to 140° C. In embodiments, the coated substrate 100 may be heated at the gelation temperature for a period of time such that the gelled plastisol adheres to the substrate. In embodiments, the coated substrate 100 may then be cooled (e.g., to room temperature, to form the water swellable coating 102.

[0059] The coated substrate 100 may have improved water absorption capacity to prevent the ingress of water. In embodiments, the coated substrate 100 may have a water absorption capacity of 5 gram / gram to 800 gram / gram. In embodiments, the coated substrate 100 may have a water absorption capacity greater than or equal to 5 gram / gram, greater than or equal to 50 gram / gram, greater than or equal to 100 gram / gram, greater than or equal to 150 gram / gram, greater than or equal to 200 gram / gram, greater than or equal to 250 gram / gram, greater than or equal to 300 gram / gram, greater than or equal to 350 gram / gram, greater than or equal to 400 gram / gram, or even greater than or equal to 450 gram / gram. In embodiments, the coated substrate 100 may have a water absorption capacity less than or equal to 800 gram / gram, less than or equal to 750 gram / gram, less than or equal to 700 gram / gram, less than or equal to 650 gram / gram, less than or equal to 600 gram / gram, less than or equal to 550 gram / gram, less than or equal to 500 gram / gram, or even less than or equal to 450 gram / gram. In embodiments, the coated substrate 100 may have a water absorption capacity of from 5 gram / gram to 800 gram / gram, from 5 gram / gram to 750 gram / gram, from 5 gram / gram to 700 gram / gram, from 5 gram / gram to 650 gram / gram, from 5 gram / gram to 600 gram / gram, from 5 gram / gram to 550 gram / gram, from 5 gram / gram to 500 gram / gram, from 5 gram / gram to 450 gram / gram, from 5 gram / gram to 400 gram / gram, from 5 gram / gram to 350 gram / gram, from 5 gram / gram to 300 gram / gram, from 100 gram / gram to 800 gram / gram, from 100 gram / gram to 750 gram / gram, from 100 gram / gram to 700 gram / gram, from 100 gram / gram to 650 gram / gram, from 100 gram / gram to 600 gram / gram, from 100 gram / gram to 550 gram / gram, from 100 gram / gram to 500 gram / gram, from 100 gram / gram to 450 gram / gram, from 100 gram / gram to 400 gram / gram, from 100 gram / gram to 350 gram / gram, from 100 gram / gram to 300 gram / gram, from 200 gram / gram to 800 gram / gram, from 200 gram / gram to 750 gram / gram, from 200 gram / gram to 700 gram / gram, from 200 gram / gram to 650 gram / gram, from 200 gram / gram to 600 gram / gram, from 200 gram / gram to 550 gram / gram, from 200 gram / gram to 500 gram / gram, from 200 gram / gram to 450 gram / gram, from 200 gram / gram to 400 gram / gram, from 200 gram / gram to 350 gram / gram, from 200 gram / gram to 300 gram / gram, from 350 gram / gram to 800 gram / gram, from 350 gram / gram to 750 gram / gram, from 350 gram / gram to 700 gram / gram, from 350 gram / gram to 650 gram / gram, from 350 gram / gram to 600 gram / gram, from 350 gram / gram to 550 gram / gram, from 350 gram / gram to 500 gram / gram, from 350 gram / gram to 450 gram / gram, or even from 350 gram / gram to 400 gram / gram, or any and all subranges formed from any of these endpoints.

[0060] The coated substrate 100 may be cut, converted, formed, or incorporated into other articles for various uses.

[0061] For example, referring now to FIG. 2, a cable 150 is shown including a cable jacket 152 and cable components 154 that are enveloped by the cable jacket 152. The cable components 154 may be conductors, optical fibers, strength members, rip cords, or fillers. The water swellable coating described herein may be incorporated into such a cable 150 in a variety of ways such that different parts of the cable 150 may be the coated substrate.

[0062] For example, referring now to FIG. 3, a cable 200 is shown including a cable jacket 202, a buffer tube 203, and cable components 204 that are enveloped by the cable jacket 202 and the buffer tube 203. In embodiments, the buffer tube 203 may be a fiber optic buffer tube. In this embodiment, the buffer tube 203 is the coated substrate, being coated with water swellable coating 206. Accordingly, if water enters the cable 200 through a rupture or defect in the cable jacket 202 or the buffer tube 203, the water swellable coating 206 may absorb the water and expand to prevent further ingression of water towards the cable components 204.

[0063] In embodiments, the fiber optic buffer tube may have an initial water ingress of less than a similar buffer tube, wherein the similar buffer tube is identical with the exception that it includes a PVC plastisol binder when tested according to IEC 60794-1-22 Method 5FB without a pre-soak. For example, in embodiments, the fiber optic buffer tube may have an initial water ingress of less than 40 cm or even less than or equal to 35 cm, when tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

[0064] In embodiments, the fiber optic buffer tube may have a water ingress after 24 hours of less than 100 cm, less than 85 cm, less than or equal to 70 cm, less than or equal to 55 cm, or even less than or equal to 40 cm, when tested according to IEC 60794-1-22 Method F5B without a pre-soak.

[0065] One skilled in the art would appreciate that the amount of water ingress of the fiber optic buffer tube is dependent on a variety of factors, such as the number of layers of the buffer tube and the amount of void in the buffer tube.

[0066] In another example, referring now to FIG. 4, a cable 300 is shown including a cable jacket 302 and cable components 304. In this embodiment, the cable components 304 are the coated substrates and are coated with water swellable coating 306. The cable components 304 may be collectively coated with the water swellable coating 306, such that the water swellable coating acts as a gel. The water swellable coating 306 may be utilized to fill interstices within the cable jacket 302 and among the cable components 304. Alternatively, the cable components 304 may individually be coated with the water swellable coating 306. Similar to the embodiment shown in FIG. 3, if water enters cable 300 through a rupture or defect in the cable jacket 302, the water swellable coating 306 may absorb the water and expand to prevent further ingression of water toward the cable components 304.

[0067] In yet another example, referring now to FIG. 5, a cable 400 is shown including a cable jacket 402 and cable components 404. In this embodiment, known as a “dry cable” design, a continuous filament yarn 406 is the coated substrate and is coated with a water swellable coating. In embodiments, the continuous filament yarn 406 may be woven or knitted to form a fabric; cut and reassembled into a non-woven textile; used as a binder, filler or strength member in the cable 400. The continuous filament yarn 406 coated with the water swellable coating may protect cable components 404 from physical damage. In the event that the cable jacket 402 is compromised and water enters the cable jacket 402, the continuous filament yarn 406 with water swellable coating absorbs water and swells to fill interstices within the cable 400. The now-swollen, continuous filament yarn 406 blocks the further penetration of water.Processing

[0068] In embodiments, a method of preparing the water swellable coating described herein may comprise blending the plastisol binder, including the water soluble polymer and the plasticizer, and the SAP to form a slurry and mixing until the slurry is homogenous.Examples

[0069] Table 1 below shows the sources of ingredients used to form Examples E1-E4.TABLE 1IngredientChemical DescriptionBrandSourceWater SolubleHydroxypropyl methyl celluloseMETHOCELDuPontPolymerPolyvinyl AlcoholPOVAL 49-88 S2KurarayPlasticizerPropylene GlycolUSP Grade PropyleneNature's OilGlycolSuperabsorbentSodium Polyacrylate SAPMAX 400-53Stewart SuperabsorbentsPolymerAQUAKEEP 10SF-SAPSumitomo SeikaSubstratePET-Polyester YarnDIOLENPHPPara-aramid YarnKEVLARFiber-lineGauzeXPECTFirst Aid Direct

[0070] Table 2 below shows the formulations used to form water swellable coating examples E1-E3. Table 2 also lists the coating weight and water absorption capacity of the coated substrate in units of grams of water per gram of coated substrate.TABLE 2E1E2E3Wt. %Wt. %Wt. %USP Grade Propylene Glycol20.0069.3035.00POVAL 49-88 S210.000.7035.00AQUAKEEP 10SF-SAP70.0030.0030.00TOTAL100.00100.00100.00Coating Weight (wt. %)45%10%30%Absorption Capacity (gram H2O / gram92728coated substrate)

[0071] To form Example E1, a mixture of AQUAKEEP 10SF-SAP (SAP), USP Grade Propylene Glycol (plasticizer), and POVAL 49-88 S2 (water soluble polymer) was prepared in a mixer. The mixture was spread between two layers of XPECT (substrate) and placed in a heat press at 140° C. for 30 seconds. The coated XPECT was removed from the heat press and cooled to room temperature. The coated XPECT had a water absorption capacity of 92 grams of water per gram of coated substrate.

[0072] To form Example E2, a mixture of AQUAKEEP 10SF-SAP (SAP), USP Grade Propylene Glycol (plasticizer), and POVAL 49-88 S2 (water soluble polymer) was prepared in a mixer. A 1000 denier para-aramid yarn KEVLAR (substrate) was coated with the mixture and placed in an oven heated to 180° C. for 40 seconds. The coated KEVLAR was removed from the oven and cooled to room temperature. The coated KEVLAR had a water absorption capacity of 7 grams of water per gram of coated substrate.

[0073] To form Example E3, a mixture consisting of AQUAKEEP 10SF-SAP (SAP), USP Grade Propylene Glycol (plasticizer), and POVAL 49-88 S2 (water soluble polymer) was prepared in a mixer. The mixture was spread between two layers of XPECT (substrate) and placed in a heat press at 140° C. for 30 seconds. The coated XPECT was removed from the heat press and cooled to room temperature. The coated XPECT had a water absorption capacity of 28 grams of water per gram of coated substrate.

[0074] As exemplified by Examples E1-E3 in Table 2, water swellable coatings as described herein may be used to form coated substrates with increased water absorption capacity.

[0075] Table 3 below shows the formulation used to form water swellable coating example E4. Table 3 also lists the coating weight, water absorption capacity of the coated substrate in units of grams of water per gram of coated substrate, initial water ingress, and 24-hour water ingress of the coated substrate.TABLE 3E4Wt. %METHOCEL 8%USP Grade Propylene Glycol72%MAX 400-5320%TOTAL100.00Coating Weight (wt. %)56%Absorption Capacity (gram H2O / gram coated substrate)68Initial Water Ingress (cm)33.724-Hour Water Ingress (cm)34.3

[0076] To form example E4, DIOLEN (substrate) was coated with a water swellable coating shown in Table 3. To apply the coating, the DIOLEN was passed through a bath, excess coating was wiped off using a die, and the coated DIOLEN was passed through an oven. The temperature and speed of the DIOLEN was adjusted until the coating was properly fused. The resulting coated DIOLEN with one end (i.e., one thread) had a water absorption capacity of 68 grams of water per gram of coated substrate, an initial water ingress of 33.7 cm, and a 24-hour water ingress of 34.3 cm.

[0077] As exemplified by Example E4 in Table 3, water swellable coatings including superabsorbent polymer and plastisol binder, including water soluble polymers and plasticizer, may be used to coat substrates to provide increased water absorption capacity and improved resistance to water ingress.

[0078] It will be apparent that modifications and variations are possible without departing from the scope of the disclosure defined in the appended claims. More specifically, although some aspects of the present disclosure are identified herein as preferred or particularly advantageous, it is contemplated that the present disclosure is not necessarily limited to these aspects.

Claims

1. A coated substrate comprising:a water swellable coating applied to a substrate,wherein the water swellable coating comprises, based on a total weight of the water swellable coating:30 wt. % to 90 wt. % of a plastisol binder, the plastisol binder comprising, based on a total weight of the plastisol binder:1 wt. % to 50 wt. % of water soluble polymer; and50 wt. % to 99 wt. % plasticizer; and10 wt. % to 70 wt. % of a superabsorbent polymer.

2. The coated substrate of claim 1, wherein the substrate comprises a yarn, fabric, textile, non-woven, paper, sheet, net, or scrim.

3. The coated substrate of claim 1, wherein the substrate comprises a continuous fiber reinforcement, yarn, fabric, textile, non-woven, paper, sheet, net, or scrim.

4. The coated substrate of claim 1, wherein the substrate comprises a continuous fiber reinforcement.

5. The coated substrate of claim 1 or claim 2, wherein the substrate consists of fibers of polyamide, aramid or copolymers thereof, cellulose regenerated fibers, polyester, polyolefin, polyacrylic, polybenzoxazole, liquid crystalline polymer, fiberglass, basalt, rock wool, ceramic, metal, carbon, plant based fibers, animal based fibers, or combinations thereof.

6. The coated substrate of any of the preceding claims, wherein the superabsorbent polymer is a superabsorbent polymer powder.

7. The coated substrate of any of the preceding claims, wherein the superabsorbent polymer has a water absorption capacity of 10 gram / gram up to 1000 gram / gram.

8. The coated substrate of any of the preceding claims, wherein the superabsorbent polymer comprises salts of polyacrylate-based polymer, polyacrylamide-based polymer, or combinations thereof.

9. The coated substrate of claim 8, wherein the salt of polyacrylate-based polymer comprises sodium polyacrylate-based polymers, potassium polyacrylate-based polymers, ammonium polyacrylate-based polymers, or combinations thereof.

10. The coated substrate of any of the preceding claims, wherein the plastisol binder further comprises 1 wt. % to 20 wt. % of an additive, based on the total weight of the plastisol binder.

11. The coated substrate of claim 10, wherein the additive is selected from the group consisting of viscosity modifiers, viscosity stabilizers, heat stabilizers, UV stabilizer, dyes, pigments, preservatives, fillers, adhesion promoters, lubricants, and combinations thereof.

12. The coated substrate of any of the preceding claims, wherein the water soluble polymer is selected from the group consisting of polyvinyl alcohols, polyacrylic acid copolymer, poly(2-ethyl-2-oxazoline), polyvinylpyrrolidone, and combinations thereof.

13. The coated substrate of any of claims 1-11, wherein the water soluble polymer is selected from the group consisting of polysaccharides, polypeptides, and combinations thereof.

14. The coated substrate of any of the preceding claims, wherein the plasticizer comprises a polyol.

15. The coated substrate of any of claims 1-13, wherein the plasticizer is selected from the group consisting of glycols, sugar alcohols, sugars, glycerol, triacetin, propylene carbonate, fatty acids, urea, and combinations thereof.

16. A fiber optic cable comprising:optical fibers; anda fiber optic buffer tube, wherein the fiber optic buffer tube comprises the coated substrate of any of the preceding claims.

17. The fiber optic cable of claim 16, wherein the fiber optic buffer tube has an initial water ingress of less than a similar buffer tube, wherein the similar buffer tube is identical with the exception that it includes a PVC plastisol binder when tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

18. The fiber optic cable of claim 16 or claim 17, wherein the fiber optic buffer tube has an initial water ingress of less than 40 cm when tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

19. The fiber optic cable of claim 18, wherein the fiber optic buffer tube has an initial water ingress of less than 35 cm when tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

20. The fiber optic cable of any one of claims 16-19, wherein the fiber optic buffer tube has a water ingress after 24 hours of less than 100 cm when tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

21. The fiber optic cable of claim 20, wherein the fiber optic buffer tube has a water ingress after 24 hours of less than 85 cm when tested according to IEC 60794-1-22 Method 5FB without a pre-soak.

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