US20020004138A1 - Novel optical fiber gel fluid - Google Patents
Novel optical fiber gel fluid Download PDFInfo
- Publication number
- US20020004138A1 US20020004138A1 US09/800,063 US80006301A US2002004138A1 US 20020004138 A1 US20020004138 A1 US 20020004138A1 US 80006301 A US80006301 A US 80006301A US 2002004138 A1 US2002004138 A1 US 2002004138A1
- Authority
- US
- United States
- Prior art keywords
- fiber optic
- gel
- olefin
- ethylene
- alpha
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000012530 fluid Substances 0.000 title abstract description 11
- 239000013307 optical fiber Substances 0.000 title abstract description 7
- 239000000835 fiber Substances 0.000 claims description 30
- 229920000098 polyolefin Polymers 0.000 claims description 16
- 239000004711 α-olefin Substances 0.000 claims description 16
- 239000000203 mixture Substances 0.000 claims description 15
- -1 C12 olefin Chemical class 0.000 claims description 10
- 229920000642 polymer Polymers 0.000 claims description 10
- AFFLGGQVNFXPEV-UHFFFAOYSA-N 1-decene Chemical compound CCCCCCCCC=C AFFLGGQVNFXPEV-UHFFFAOYSA-N 0.000 claims description 8
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 7
- 239000003795 chemical substances by application Substances 0.000 claims description 7
- 239000003349 gelling agent Substances 0.000 claims description 6
- 239000003381 stabilizer Substances 0.000 claims description 6
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 5
- 239000005977 Ethylene Substances 0.000 claims description 5
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 claims description 4
- 125000004432 carbon atom Chemical group C* 0.000 claims description 4
- 230000001590 oxidative effect Effects 0.000 claims description 4
- 229920006132 styrene block copolymer Polymers 0.000 claims description 4
- 229920001400 block copolymer Polymers 0.000 claims description 3
- 239000002562 thickening agent Substances 0.000 claims description 3
- 239000008119 colloidal silica Substances 0.000 claims description 2
- 229920001971 elastomer Polymers 0.000 claims description 2
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 claims description 2
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims description 2
- 239000000377 silicon dioxide Substances 0.000 claims description 2
- 238000004227 thermal cracking Methods 0.000 claims description 2
- JRZJOMJEPLMPRA-UHFFFAOYSA-N olefin Natural products CCCCCCCC=C JRZJOMJEPLMPRA-UHFFFAOYSA-N 0.000 claims 9
- 150000001336 alkenes Chemical class 0.000 claims 6
- VXNZUUAINFGPBY-UHFFFAOYSA-N 1-Butene Chemical compound CCC=C VXNZUUAINFGPBY-UHFFFAOYSA-N 0.000 claims 2
- ZGEGCLOFRBLKSE-UHFFFAOYSA-N 1-Heptene Chemical compound CCCCCC=C ZGEGCLOFRBLKSE-UHFFFAOYSA-N 0.000 claims 2
- LIKMAJRDDDTEIG-UHFFFAOYSA-N 1-hexene Chemical compound CCCCC=C LIKMAJRDDDTEIG-UHFFFAOYSA-N 0.000 claims 2
- KWKAKUADMBZCLK-UHFFFAOYSA-N 1-octene Chemical compound CCCCCCC=C KWKAKUADMBZCLK-UHFFFAOYSA-N 0.000 claims 2
- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 claims 2
- YWAKXRMUMFPDSH-UHFFFAOYSA-N pentene Chemical compound CCCC=C YWAKXRMUMFPDSH-UHFFFAOYSA-N 0.000 claims 2
- 239000004927 clay Substances 0.000 claims 1
- TVMXDCGIABBOFY-UHFFFAOYSA-N n-Octanol Natural products CCCCCCCC TVMXDCGIABBOFY-UHFFFAOYSA-N 0.000 claims 1
- QQONPFPTGQHPMA-UHFFFAOYSA-N propylene Natural products CC=C QQONPFPTGQHPMA-UHFFFAOYSA-N 0.000 claims 1
- 125000004805 propylene group Chemical group [H]C([H])([H])C([H])([*:1])C([H])([H])[*:2] 0.000 claims 1
- 239000000499 gel Substances 0.000 description 32
- 229920013639 polyalphaolefin Polymers 0.000 description 8
- 230000003993 interaction Effects 0.000 description 7
- 239000000463 material Substances 0.000 description 7
- 239000003921 oil Substances 0.000 description 7
- 230000003287 optical effect Effects 0.000 description 5
- 230000008961 swelling Effects 0.000 description 5
- 239000004743 Polypropylene Substances 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 229920001155 polypropylene Polymers 0.000 description 4
- 229920002633 Kraton (polymer) Polymers 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 239000004215 Carbon black (E152) Substances 0.000 description 2
- 239000004698 Polyethylene Substances 0.000 description 2
- 239000002199 base oil Substances 0.000 description 2
- 230000000740 bleeding effect Effects 0.000 description 2
- 229920001577 copolymer Polymers 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 239000011968 lewis acid catalyst Substances 0.000 description 2
- 229920000573 polyethylene Polymers 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- 229920001897 terpolymer Polymers 0.000 description 2
- VFBJXXJYHWLXRM-UHFFFAOYSA-N 2-[2-[3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoyloxy]ethylsulfanyl]ethyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoate Chemical compound CC(C)(C)C1=C(O)C(C(C)(C)C)=CC(CCC(=O)OCCSCCOC(=O)CCC=2C=C(C(O)=C(C=2)C(C)(C)C)C(C)(C)C)=C1 VFBJXXJYHWLXRM-UHFFFAOYSA-N 0.000 description 1
- 229920000089 Cyclic olefin copolymer Polymers 0.000 description 1
- 150000001338 aliphatic hydrocarbons Chemical class 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 239000003963 antioxidant agent Substances 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 239000000440 bentonite Substances 0.000 description 1
- 229910000278 bentonite Inorganic materials 0.000 description 1
- SVPXDRXYRYOSEX-UHFFFAOYSA-N bentoquatam Chemical compound O.O=[Si]=O.O=[Al]O[Al]=O SVPXDRXYRYOSEX-UHFFFAOYSA-N 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007850 degeneration Effects 0.000 description 1
- 230000003292 diminished effect Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920005676 ethylene-propylene block copolymer Polymers 0.000 description 1
- 229910021485 fumed silica Inorganic materials 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000002480 mineral oil Substances 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004417 polycarbonate Substances 0.000 description 1
- 229920000515 polycarbonate Polymers 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 229920005862 polyol Polymers 0.000 description 1
- 150000003077 polyols Chemical class 0.000 description 1
- 229920001451 polypropylene glycol Polymers 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 230000008719 thickening Effects 0.000 description 1
- 230000009974 thixotropic effect Effects 0.000 description 1
- 229910052723 transition metal Inorganic materials 0.000 description 1
- 150000003624 transition metals Chemical class 0.000 description 1
- 239000013638 trimer Substances 0.000 description 1
- 230000004584 weight gain Effects 0.000 description 1
- 235000019786 weight gain Nutrition 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
- G02B6/4401—Optical cables
- G02B6/4429—Means specially adapted for strengthening or protecting the cables
- G02B6/44384—Means specially adapted for strengthening or protecting the cables the means comprising water blocking or hydrophobic materials
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/02—Optical fibres with cladding with or without a coating
- G02B6/032—Optical fibres with cladding with or without a coating with non solid core or cladding
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/29—Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
- Y10T428/2913—Rod, strand, filament or fiber
- Y10T428/2933—Coated or with bond, impregnation or core
Definitions
- the present invention generally relates to a novel optical fiber gel fluid. More particularly the present invention relates to an optical fiber gel fluid comprising ethylene-alpha-olefin copolymers.
- polyolefins can lead to improvements in cable performance and reduced cost, they may not be compatible with many traditional, low cost polyolefin and hydrocarbon-based cable gel compounds. In systems where strong swelling interactions exist, lifetimes can be reduced to a small fraction of that which would be observed for the virgin polymer. This incompatibility is due to favorable solvent-polymer interactions between polyolefins and polyolefin-based gels. The commercially available cable waterblocking gels have very significant compound to compound variation in compatibility with polyolefins.
- PAOs polyalphaolefins
- ethylene is oligomerized with aluminum alkyl to produce a range of linear alpha-olefins having even numbers carbon atoms from C 4 to C 30+ .
- linear alpha-olefins are produced that serve distinct markets growing at different rates.
- about 25% of the linear alpha-olefins are 1-Decene, the major component of PAO.
- PAO is generally prepared by reaction of 1-Decene with a Lewis Acid catalyst such as BF 3 to produce primarily trimers and tetramers.
- a Lewis Acid catalyst such as BF 3
- 1-Decene is expensive and costs about three times more than ethylene making PAO very expensive.
- Other examples of Lewis Acid catalysts used to produce higher molecular weight PAOs are alkyl aluminum halides such as those disclosed in U.S. Pat. Nos. 4,469,910 and 4,594,469, both of which are incorporated herein by reference.
- polyol-based and high molecular weight polyalphaolefin waterblocking gels have been utilized, especially for buffer tube filling applications, which offer better compatibility due to less favorable polymer-gel interactions.
- these gels are even more expensive, which decreases the cost savings associated with use of polyolefins such as polypropylene for buffer tube applications.
- the present invention provides a novel optical fiber cable gel for use with fiber optic elements.
- the gels are made from fluids of high molecular weight ethylene-alpha-olefin polymers produced by polymerization of ethylene, an alpha-olefin different from ethylene, and optionally a third monomer different from the alpha-olefin and having 3 to 20 carbon atoms, in the presence of a combination catalyst comprising a compound of a transition metal of Group IVb of the Periodic Table and an aluminoxane.
- the copolymer or terpolymer may be further processed by thermal cracking to yield novel cracked polymers, and the cracked polymers may be hydrogenated.
- the copolymers or terpolymers may also be hydroisomerized.
- the ethylene-alpha-olefin polymers useful in the practice of the present invention are those having a low pour point, less than about ⁇ 30° C. and a relatively high molecular weight, such as greater than 700, preferably greater than 1000, more preferably greater than 1100 and most preferably up to about 2000 or more.
- These ethylene-alpha-olefin polymers and their method of production as fully set forth in International Application No. PCT/US98/12621 published under International Publication Number WO 98/58972 which is hereby incorporated by reference in its entirety.
- the above-described fluids are generally present in an amount of 85% by weight or more based on the weight of the entire gel composition.
- the molecular weight distribution of these fluids has a dramatic influence on the swelling interaction. Gels with large molecular weight components swell a given polymer most severely.
- the polymerized fraction utilized in the present invention has a kinematic viscosity at 100° C. of greater than 10 cSt, a flash point of greater than 235° C. and a pour point of ⁇ 30° C. or less.
- the fluids of the present invention create a swelling weight gain of less than 3% in three different fiber optic grades of impact modified polypropylene.
- gelling agent such as are known to those of ordinary skill in the art.
- Preferred gelling agents are fumed silica, colloidal silica, either hydrophilic or hydrophobic, precipitated silicas and clays such as bentonite with or without surface treatment.
- Other inorganic colloidal particles may also be used, if desired, although the silicas are preferred.
- the gelling agent is present in an amount ranging from about 5 to 8 percent by weight based on the weight of the entire gel composition.
- an effective amount of a bleed resistant agent may be added to the gels.
- a bleed resistant agent known to those skilled in the art to prevent the gels from bleeding through the polymer sheath may be employed.
- Block copolymers are preferred bleed resistant agents, such as styrene-rubber and styrene-rubber-styrene block copolymers.
- styrene-ethylene-propylene block copolymer sold under the trade designation Kraton G1701 or G1702
- SEBS styrene-ethylene butylene-styrene block copolymer
- Kraton 1726 a styrene block copolymer mixture sold under the trade designation Kraton 1726.
- the bleed resistant agent is employed in an amount ranging from about 3 to about 6 weight percent based on the weight of the total gel composition.
- thermal and/or oxidative stabilizer may also be added to the gels of the present invention as is known to those of ordinary skill in the art.
- thickening agents where necessary. These especially useful in the practice of the present invention to increase the viscosity of the gel by increasing the interaction possibilities between the silica and the oil. A small amount of glycol, such as polypropylene glycol, may be added.
- Swelling of coating materials for optical fibers in contact with the filling gels of the present invention is substantially reduced over that seen with prior art filling materials.
- the use of a low pour point aliphatic hydrocarbon in the filling gel allows the cable to provide superior optical performance at low temperatures.
- the filling gel composition of the present invention encompasses the fibers.
- the fibers and the filling material are contained within a tubular member which is disposed within a sheath system.
- the sheath system includes longitudinally extending strength members and a plastic jacket. See for example the above-mentioned U.S. Pat. Nos. 5,285,513 and 5,187,763.
- the filling composition of the present invention comprises at least about 85 percent by weight of the above-described oils having a molecular weight of at least about 700. Relatively low pour point oils are preferred in order to improve optical loss at low temperature.
- a thickening system which includes an inorganic constituent and a block copolymer is preferred to form the gel as well as to reduce oil separation.
- An antioxidant is used to prevent thermal oxidative degeneration of the filling gels of the present invention.
- a grease-like filling composition prepared in accordance with the present invention having a relative high critical yield stress allows the inside diameter of tubes to increase.
- a larger tube can incorporate a larger amount of optical fibers in the form of stacked ribbons. The result in an increase in bandwidth.
- compositions formed in accordance with the present invention are thixotropic and are operable over a wide temperature range. They are water resistand and remain soft at both ends of the relevant temperature spectrum. They are compatible with a variety of jacket materials, including polypropylene, polyethylene, polycarbonate, etc, at other cable materials which they contact.
- the filling material of the present invention has enhanced performance at low temperature because of the use of a low pour point oil and very low oil separation. There is no bleeding of oil and it is expected that the optical loss at ⁇ 40° C. will not exceed that of the prior art filling materials.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Insulated Conductors (AREA)
Abstract
A novel optical fiber gel fluid is provided.
Description
- This application claims priority from U.S. Provisional Application Ser. No. 60/187,459, filed Mar. 6, 2000, currently pending.
- The present invention generally relates to a novel optical fiber gel fluid. More particularly the present invention relates to an optical fiber gel fluid comprising ethylene-alpha-olefin copolymers.
- In providing cushioning of the fiber optic elements which are carried in a jacket or sheath, care must be taken to assure that the optical qualities of the fiber optic elements are not diminished. It is desirable for buffer tube as well as cable jacket polymer and waterblocking gels to have as little interaction as possible. Compatibility of a polymer gel system in flooded cable designs can have a serious effect on cable lifetime and reliability. Since 1995, polypropylene and polyethylene buffer tubes have become increasingly attractive from an application and installation standpoint.
- Although polyolefins can lead to improvements in cable performance and reduced cost, they may not be compatible with many traditional, low cost polyolefin and hydrocarbon-based cable gel compounds. In systems where strong swelling interactions exist, lifetimes can be reduced to a small fraction of that which would be observed for the virgin polymer. This incompatibility is due to favorable solvent-polymer interactions between polyolefins and polyolefin-based gels. The commercially available cable waterblocking gels have very significant compound to compound variation in compatibility with polyolefins.
- Currently, polyalphaolefins (PAOs) are the dominant hydrocarbon synthetic base oil on which the gels are based. However, costs are high compared to conventional mineral base oils. Generally, the PAO's are manufactured in two steps. First, ethylene is oligomerized with aluminum alkyl to produce a range of linear alpha-olefins having even numbers carbon atoms from C 4 to C30+. About fifteen linear alpha-olefins are produced that serve distinct markets growing at different rates. About 25% of the linear alpha-olefins are 1-Decene, the major component of PAO.
- PAO is generally prepared by reaction of 1-Decene with a Lewis Acid catalyst such as BF 3 to produce primarily trimers and tetramers. 1-Decene is expensive and costs about three times more than ethylene making PAO very expensive. Other examples of Lewis Acid catalysts used to produce higher molecular weight PAOs are alkyl aluminum halides such as those disclosed in U.S. Pat. Nos. 4,469,910 and 4,594,469, both of which are incorporated herein by reference.
- As an alternative, polyol-based and high molecular weight polyalphaolefin waterblocking gels have been utilized, especially for buffer tube filling applications, which offer better compatibility due to less favorable polymer-gel interactions. Compared to waterblocking gels based on mineral oils, however, these gels are even more expensive, which decreases the cost savings associated with use of polyolefins such as polypropylene for buffer tube applications.
- Exemplary conventional gels are described in Brauer et al., U.S. Pat. No. 5,433,872; Brauer et al., U.S. Pat. No. 5,348,669; Randisi, U.S. Pat. No. 5,050,959; Kaufman et al., U.S. Pat. No. 5,285,513; and Tu, U.S. Pat. No. 5,187,763, all of which are incorporated herein by reference in their entirety.
- While the known water resistant optical cable gel fluids possess some unique features, they are expensive and not completely suitable for many potential applications. Thus, there is a need in the art for an improved, lower cost cable gel fluid which is water resistant, has a wide service temperature range, high shear and oxidation stability, low toxicity and has reduced influence on the swelling interaction with polyolefin buffer tubes.
- The present invention provides a novel optical fiber cable gel for use with fiber optic elements. The gels are made from fluids of high molecular weight ethylene-alpha-olefin polymers produced by polymerization of ethylene, an alpha-olefin different from ethylene, and optionally a third monomer different from the alpha-olefin and having 3 to 20 carbon atoms, in the presence of a combination catalyst comprising a compound of a transition metal of Group IVb of the Periodic Table and an aluminoxane. The copolymer or terpolymer may be further processed by thermal cracking to yield novel cracked polymers, and the cracked polymers may be hydrogenated. The copolymers or terpolymers may also be hydroisomerized.
- The ethylene-alpha-olefin polymers useful in the practice of the present invention are those having a low pour point, less than about −30° C. and a relatively high molecular weight, such as greater than 700, preferably greater than 1000, more preferably greater than 1100 and most preferably up to about 2000 or more. These ethylene-alpha-olefin polymers and their method of production as fully set forth in International Application No. PCT/US98/12621 published under International Publication Number WO 98/58972 which is hereby incorporated by reference in its entirety.
- The above-described fluids are generally present in an amount of 85% by weight or more based on the weight of the entire gel composition. The molecular weight distribution of these fluids has a dramatic influence on the swelling interaction. Gels with large molecular weight components swell a given polymer most severely. The polymerized fraction utilized in the present invention has a kinematic viscosity at 100° C. of greater than 10 cSt, a flash point of greater than 235° C. and a pour point of −30° C. or less. The fluids of the present invention create a swelling weight gain of less than 3% in three different fiber optic grades of impact modified polypropylene.
- The above-described fluids are then gelled with an effective amount of gelling agent such as are known to those of ordinary skill in the art. Preferred gelling agents are fumed silica, colloidal silica, either hydrophilic or hydrophobic, precipitated silicas and clays such as bentonite with or without surface treatment. Other inorganic colloidal particles may also be used, if desired, although the silicas are preferred. Generally the gelling agent is present in an amount ranging from about 5 to 8 percent by weight based on the weight of the entire gel composition.
- Optionally, an effective amount of a bleed resistant agent may be added to the gels. Any such bleed resistant agents known to those skilled in the art to prevent the gels from bleeding through the polymer sheath may be employed. Block copolymers are preferred bleed resistant agents, such as styrene-rubber and styrene-rubber-styrene block copolymers. Commercially available examples are a styrene-ethylene-propylene block copolymer (SEP) sold under the trade designation Kraton G1701 or G1702, a styrene-ethylene butylene-styrene block copolymer (SEBS) sold under the trade designation Kraton G1657, or a styrene block copolymer mixture sold under the trade designation Kraton 1726. Preferably the bleed resistant agent is employed in an amount ranging from about 3 to about 6 weight percent based on the weight of the total gel composition.
- Optionally, an effective amount of thermal and/or oxidative stabilizer may also be added to the gels of the present invention as is known to those of ordinary skill in the art. Preferred are hindered phenolic stabilizers such as those available from Ciba-Geigy Company under the trade designation Irganox 1035. In preferred embodiments these are present in amounts ranging from about 1 to about 2 percent by weight based on the weight of the total gel composition.
- It is also contemplated to add effective amounts of thickening agents where necessary. These especially useful in the practice of the present invention to increase the viscosity of the gel by increasing the interaction possibilities between the silica and the oil. A small amount of glycol, such as polypropylene glycol, may be added.
- Swelling of coating materials for optical fibers in contact with the filling gels of the present invention is substantially reduced over that seen with prior art filling materials. The use of a low pour point aliphatic hydrocarbon in the filling gel allows the cable to provide superior optical performance at low temperatures.
- The filling gel composition of the present invention encompasses the fibers. Typically, the fibers and the filling material are contained within a tubular member which is disposed within a sheath system. The sheath system includes longitudinally extending strength members and a plastic jacket. See for example the above-mentioned U.S. Pat. Nos. 5,285,513 and 5,187,763.
- The filling composition of the present invention comprises at least about 85 percent by weight of the above-described oils having a molecular weight of at least about 700. Relatively low pour point oils are preferred in order to improve optical loss at low temperature.
- A thickening system which includes an inorganic constituent and a block copolymer is preferred to form the gel as well as to reduce oil separation. An antioxidant is used to prevent thermal oxidative degeneration of the filling gels of the present invention.
- A grease-like filling composition prepared in accordance with the present invention having a relative high critical yield stress (as it relates to the stiffness of the gel) allows the inside diameter of tubes to increase. A larger tube can incorporate a larger amount of optical fibers in the form of stacked ribbons. The result in an increase in bandwidth.
- The compositions formed in accordance with the present invention are thixotropic and are operable over a wide temperature range. They are water resistand and remain soft at both ends of the relevant temperature spectrum. They are compatible with a variety of jacket materials, including polypropylene, polyethylene, polycarbonate, etc, at other cable materials which they contact.
- The filling material of the present invention has enhanced performance at low temperature because of the use of a low pour point oil and very low oil separation. There is no bleeding of oil and it is expected that the optical loss at −40° C. will not exceed that of the prior art filling materials.
Claims (22)
1. A fiber optic gel comprising:
(a) an ethylene-alpha-olefin polymer comprising:
(i) 10 to 80% ethylene,
(ii) 14 to 80% of a first olefin having from 3 to 20 carbon atoms, and
(iii) 0 to 10% of a second olefin having from 3 to 20 carbon atoms which is different from said first olefin;
wherein said ethylene-alpha-olefin has a molecular weight of greater than about 700 and a pour point of less than about −30° C.; and
(b) an effective amount of a gelling agent.
2. A fiber optic gel as defined in claim 1 wherein said first olefin comprises propylene.
3. A fiber optic gel as defined in claim 1 wherein said second olefin comprises a C4 to C12 olefin.
4. A fiber optic gel as defined in claim 1 wherein said second olefin is selected from the group consisting of 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, styrene and mixtures thereof.
5. A fiber optic gel as defined in claim 1 wherein said ethylene-alpha-olefin polymer has a molecular weight of greater than 1000.
6. A fiber optic gel as defined in claim 1 wherein said ethylene-alpha-olefin polymer has a molecular weight of greater than 1100.
7. A fiber optic gel as defined in claim 1 wherein said ethylene-alpha-olefin polymer has a molecular weight of greater than 2000.
8. A fiber optic gel as defined in claim 1 wherein said gelling agent is selected from the group consisting of silica, colloidal silica, precipitated silica, clay and mixtures thereof.
9. A fiber optic gel as defined in claim 1 further comprising (c) an effective amount of a bleed resistant agent.
10. A fiber optic gel as defined in claim 9 wherein said bleed resistant agent comprises a styrene-rubber block copolymer, a styrene-rubber-styrene block copolymer or a mixture thereof.
11. A fiber optic gel as defined in claim 1 further comprising (d) an effective amount of a thermal/oxidative stabilizer.
12. A fiber optic gel as defined in claim 11 wherein said stabilizer comprises a hindered phenolic stabilizer.
13. A fiber optic gel as defined in claim 1 further comprising (e) an effective amount of a thickening agent.
14. A fiber optic gel as defined in claim 13 wherein said thickening agent comprises a glycol.
15. A fiber optic gel as defined in claim 1 wherein said ethylene-alpha-olefin polymer is further processed by thermal cracking.
16. A fiber optic gel as defined in claim 15 wherein said thermally cracked polymer is hydrogenated.
17. A fiber optic gel as defined in claim 15 wherein said thermally cracked polymer is hydroisomerized.
18. A fiber optic gel as defined in claim 1 wherein said effective amount of gelling agent comprises an amount ranging from about 5 to about 8 weight percent of the total gel composition.
19. A fiber optic gel as defined in claim 9 wherein said effective amount of bleed resistant agent comprises an amount ranging from about 1 to about 2 weight percent.
20. A fiber optic gel as defined in claim 11 wherein said effective amount of thermal/oxidative stabilizer comprises an amount ranging from about 1 to 2 weight percent based on the total gel composition.
21. A fiber optic gel as defined in claim 1 wherein said ethlyene-alpha-olefin polymer is present in an amount of at least about 85 weight percent based on the total gel composition.
22. A fiber optic cable comprising:
(I) a fiber optic member;
(II) surrounded by a fiber optic gel as defined in claim 1; and
(III) encased in a cable jacket.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US09/800,063 US20020004138A1 (en) | 2000-03-06 | 2001-03-05 | Novel optical fiber gel fluid |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US18745900P | 2000-03-06 | 2000-03-06 | |
| US09/800,063 US20020004138A1 (en) | 2000-03-06 | 2001-03-05 | Novel optical fiber gel fluid |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US20020004138A1 true US20020004138A1 (en) | 2002-01-10 |
Family
ID=26883054
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US09/800,063 Abandoned US20020004138A1 (en) | 2000-03-06 | 2001-03-05 | Novel optical fiber gel fluid |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US20020004138A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7619748B2 (en) * | 2004-02-27 | 2009-11-17 | Canon Kabushiki Kaisha | Exposure apparatus mounted with measuring apparatus |
| US20240053536A1 (en) * | 2020-12-14 | 2024-02-15 | Commissariat A L’Energie Atomique Et Aux Energies Alternatives | Radiation-resistant silica-based optical fibre |
| US12434022B2 (en) | 2017-04-28 | 2025-10-07 | Invox Belgium Nv | Inhalation device and method |
-
2001
- 2001-03-05 US US09/800,063 patent/US20020004138A1/en not_active Abandoned
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7619748B2 (en) * | 2004-02-27 | 2009-11-17 | Canon Kabushiki Kaisha | Exposure apparatus mounted with measuring apparatus |
| US12434022B2 (en) | 2017-04-28 | 2025-10-07 | Invox Belgium Nv | Inhalation device and method |
| US20240053536A1 (en) * | 2020-12-14 | 2024-02-15 | Commissariat A L’Energie Atomique Et Aux Energies Alternatives | Radiation-resistant silica-based optical fibre |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5187763A (en) | Optical fiber cable having dripless, non-bleeding and optical fiber coating-compatible waterblocking material in core thereof | |
| US6658185B2 (en) | Optical fiber cable with components having improved compatibility with waterblocking filling compositions | |
| AU737126B2 (en) | Optical fiber cable having an improved filling material within its core | |
| US4701016A (en) | Thixotropic grease composition and cable comprising same | |
| CA1324276C (en) | Optical fiber cable | |
| US5505773A (en) | Fiber optic buffer tube compound | |
| US5013126A (en) | Waterproof optical fiber cable | |
| NZ250264A (en) | Optical fibre cable with water blocking filler composition | |
| US7466887B2 (en) | Optical fiber cable with dimensionally stable polymeric component | |
| CN105793347A (en) | Optical fiber cable components | |
| US20020004138A1 (en) | Novel optical fiber gel fluid | |
| US6278824B1 (en) | Optical cable with filling material comprising an internal olefin oligomer | |
| US11760880B2 (en) | Gel compositions | |
| EP1214619B1 (en) | Optical fiber cable with components having improved compatibility with waterblocking filling compositions | |
| EP0969301A2 (en) | Optical cable with filling material | |
| EP1323781B1 (en) | Silicone waterblocking gel for low temperature fiber optic cables | |
| CA2273287C (en) | Optical cable with filling material | |
| AU2002316911B2 (en) | Optical fiber cable with dimensionally stable polymeric component | |
| US6377737B1 (en) | Filling compound having alumina gelling agent | |
| JPH0644090B2 (en) | Optical fiber lubrication / cushion composition | |
| US12110396B2 (en) | Gel compositions | |
| JPS63271302A (en) | communication distribution system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |