KR20110132763A - Gel composition for optical cable having low density and process for preparing it - Google Patents

Abstract

PURPOSE: A gel composition for a low density optical cable and a manufacturing method thereof are provided to light an optical cable by making the optical cable to have low density by mixing the microsphere of very low density and a pour point depressant with a gel composition. CONSTITUTION: A pour-point depressant includes 0.1 to 1.6 by weight over a base oil component. The density of the gel composition should become 0.380 to 0.550 in a microsphere of 0.028 to 0.023 by a specific gravity. Base oil is a mineral oil or the mixed oil of the mineral oil and synthetic oil.

Description

Gel composition for low density optical cable and its manufacturing method {GEL COMPOSITION FOR OPTICAL CABLE HAVING LOW DENSITY AND PROCESS FOR PREPARING IT}

The present invention relates to a low density optical cable gel composition and a method for producing the same. More particularly, the present invention relates to a gel composition for a low density optical cable and a method for producing the same, wherein the weight of the optical cable is lighter and the gel composition on the optical fiber can be easily removed when the optical cable is connected.

In the telecommunications industry, particularly in the optical telecommunications industry, it is known that changes in ambient environmental conditions cause water vapor pressure differences between the inside and outside of the resin jacket. It is common to diffuse moisture in one direction from the outside of the cable to the inside. After all, the cable, that is, the structure that prevents the ingress of moisture from the outside with only a plastic jacket, increases the water (humidity) level inside the cable, causing disconnection, failure, propagation of microorganisms, and deterioration of communication quality. You have to do it. Furthermore, if the ambient temperature falls below minus 30 ° C or rises above 50 ° C, moisture in the cable freezes or expands, adversely affecting the cable causing stress or strain. Moreover, if the cable is damaged due to such adverse effects, moisture (moisture) invades and worsens the optical fiber inside the cable, leading to a vicious cycle in which the quality of communication is deteriorated. In order to solve this problem, fillers such as petroleum gels have been used to prevent the invasion from animals such as molds and termites, and to use a water stop between a communication cable, especially an optical communication cable and the inside and the outside. Similarly to the prior art described above, the inventors have prepared an optical cable gel composition by combining an oily base, a synthetic oil, a gelling agent, an antioxidant, and the like. Cable producers have typically manufactured cables by purchasing commercially available fillers as such gel fillers, as well as providing that the gel fillers meet the above requirements, in addition to density, drpo point, viscosity, cones. Products that meet the specifications such as cone penetration, oil separation at a predetermined temperature, OIT, and optical fiber discoloration are purchased and used. Most of these standards are used by manufacturers, but most of them comply with the American Standard (ASTM). Most of these standards are taken by manufacturers, but in extreme countries such as Northern Europe and Russia, cone penetration is required to be greater than 200 dmm at -50 ° C. As a result, gel composition manufacturers typically manufacture and sell compositions for optical cable companies that require more than 200 dmm at -40 ° C. and compositions for cables in extreme countries, or collectively produce compositions for cables in extreme areas. Also sold. In preparing the gel composition for the extreme region, in order to lower the crystallization temperature of the mineral oil contained in the base oil (called base oil or oily base), the crystallization temperature is about -15 ℃ to -20 ℃ In general, a large amount of synthetic oil such as polyalpha olefin oil (PAO), which is a low flow point oil, is blended to meet the above requirements. However, when a large amount of such synthetic oil is blended, as the cost of the gel composition is increased, the economic burden of the gel composition producer is increased.

As described above, first, in order to increase cone penetration due to a base oil having a high crystallization temperature among the components of the gel composition for an optical cable, the composition for lowering the high cost of the gel composition due to the mixing of expensive synthetic oil having a low crystallization temperature In addition, the use of the optical fiber cable manufactured by the technique of the conventional method and composition as it is, the volume and weight increase as the large amount of optical fibers are discharged all at once due to the recent increase in demand, It is not easy for the worker to install by hand on the ground and underground, and also because the mechanical installation is difficult to install the mechanical equipment, thereby increasing the economic burden, there is a need for the emergence of a focused, lightweight cable.

In order to reduce the weight of such a cable, it is not possible to omit the cable or the structure inside the cable and to reduce the concentration of the optical fiber. Thus, there have been patents for blending silica and its derivatives, fume silica, rubber, foam rubber, thixotrope, organic affinity clays, and the like in the composition to solve this problem. While it helps to improve some degree of flexibility and light weight, it is accompanied by deformation and breakage over time, and moreover, it is not satisfactory to be applied to light weight of recent multiplexed and longed cables.

In order to solve the above problems, Patent Document 1 (EP 0067 009B1) discloses the use of glass bubble microspheres while preventing the moisture in the cable and disclosing the hydrophobic mineral base material for weight reduction. It is not preferable for the purpose of light weight due to its high specific gravity, and in Patent Document 2 (USP 7,253,217B2), although it is considerably lighter than a conventional cable by using a microsphere made of a copolymer of acrylonitrile and methacrylonitrile, In this composition, if a large amount of synthetic poly alpha-olefin oil is not used (reference, Example 1), the cone penetration at -40 ° C is less than 200dmm (ASTM D937), and therefore cannot be used. In the case of using a large amount of poly alpha-olefin oil to meet the standard (Reference, Example 2), the cost of the gel composition The burden is a big problem.

As described above, the higher the compounding amount of the expensive synthetic poly alpha-olefin oil (P.A.O) in the composition, the higher the production cost. Therefore, the compounding amount needs to be reduced, but no solution has been found.

Accordingly, there is a need in the art for the emergence of more innovative gel compositions that are much lighter in cables and can significantly reduce the cost of gel compositions.

Under these circumstances, the present inventors earnestly studied a method for reducing the weight of the optical fiber cable and reducing the cost of the gel composition.

First, by using a microsphere made of a copolymer of acrylonitrile and methyl methacrylate and having a specific gravity of about 0.023 to 0.028, the density required by blending at a lower weight than the microsphere (about 0.042) used in Patent Document 2, For example, 0.380 to 0.550 can achieve the desired weight reduction of the cable, and can also maintain the cone penetration by 200 ddm or more even if the amount of expensive synthetic oil such as poly alpha olefin is reduced by the addition of a small amount of pour point lowering agent. The present invention was completed.

According to the present invention, an ultra-low specific gravity microsphere and a pour point strengthening agent are blended into the gel composition to reduce the optical cable density and lighten the weight, and also to reduce the cost of the optical cable filler while reducing the compounding amount of the synthetic poly alphaolefin in the gelling agent. Accompanied by this, it provides a low density optical fiber filler with remarkably improved workability by reducing stickiness when connecting optical cables.

Hereinafter, the present invention will be described in detail.

As the required characteristics of the light-weight optical cable filler are directly in contact with the optical fiber, color discoloration coated with UV-curable resin ink should not occur to distinguish the optical fiber, and the optical loss caused by the light-weight optical cable filler Should not occur,

In particular, in the light loss test evaluation, the cone intrusion degree was 200 (1 /) at -40 ° C and -50 ° C in extreme countries to satisfy this. 10mm) or more.

The pour point of the mineral oil in the primary base composition of the optical cable filler gel composition varies depending on the manufacturer, but is generally on the order of -15 to -17 ° C. Examples of these include general mineral oils, and specific examples include SN 500 (Mobil), YUBASE 6 (SK), Ultra 6 (S-Oil), and N-1500 HT (Penreco). These mineral oils usually crystallize / solidify at low temperatures of −40 ° C., and are measured at about 150 (1/10 mm) level when measuring penetration. Due to the phenomenon of crystallization at low temperature due to this effect, the filler product manufactured based on mineral oil is applied to optical fiber due to shrinkage and applied to the standard value required by various factors such as distortion of the shape of the regular array. Light loss occurs.

Conventionally, in order to lower the flow temperature of a base oil, the polyalphaolefin oil which is a synthetic oil was mix | blended and used normally. Since such a polyalphaolefin oil has a very low flow temperature of about -68 ° C, when it is blended by about 50% within about 30, the flow point of the high temperature (eg, about -16 to -18 ° C) of the mineral oil used as the base oil Although it can be lowered to the desired temperature, these synthetic oils are too expensive and are a cost burden.

In order to remove the effect on the temperature, a pour point enhancer is added in an appropriate amount, so that the prepared gel composition has a penetration value at -40 ° C of 200 (dmm) or more so that light loss does not occur. In addition, compatibility with various raw materials constituting the optical cable should be considered.

In the present invention, as the pour point enhancer, Infineum V386 / V382 (Infineum USA) and VISCOPLEX 1-330 (RohMax GmbH & Co.) are used, but the present invention is not limited thereto. Can be. Moreover, as addition amount of a pour point strengthening agent, it is preferable to mix | blend 0.1-1.6 weight part with respect to the base oil composition which has mineral oil as a main component. That is, even if it mix | blends more than 1.6 weight part with respect to a base oil composition, fluidity will not improve, and when it mix | blends below 0.1 weight part, desired fluidity cannot be obtained.

When blending such a pour point strengthening agent in the said range, even if the compounding quantity of the synthetic oil mix | blended is reduced, it can easily maintain 200ddm or more which is the prescribed cone penetration of the gel composition of an optical fiber cable.

 The above-mentioned pour point enhancers are conventionally used gel compositions for styrene-ethylene / propylene diblock copolymer (SEP), styrene-ethylene / butylene styrene triblock copolymer (SEBS), and ethylene / propylene multiarm copolymer (EP). By adding a gelling agent such as Kraton (Shell), the compounding amount thereof can be reduced.

In order to reduce the weight of the optical fiber cable in the present invention, the density of the gel composition is 0.380 to 0.550, preferably using a microsphere having a specific gravity of about 0.023 to 0.028, which is made of a copolymer of acrylonitrile and methyl methacryl. Add until 0.420 to 0.500. In the case of using such a low specific gravity microsphere, the weight of the cable can be reduced to about 10 to 20% by weight compared with the case where a conventional microsphere having a specific gravity of about 0.042 is incorporated. An example of such a microsphere is Expensive 051 DET (Expencell 051 DET, manufactured by HAEx Chemical). That is, in order to make the density of a gel composition 0.380-0.550 using glass bubble (3M manufacture, density 0.15-0.22g / cc, particle diameter 35-95micrometer), as shown in the below-mentioned Example, it is 12-12. Although 18% by weight should be added, when the microsphere (density 0.023 to 0.028 g / cc) is used, the density of the target cable gel composition can be adjusted even if 2.5 to 3.3% by weight is added. The use of such microspheres has been used because the low temperature (flow) is low, but the weight of the optical cable is reduced during the installation of the optical cable and the removal of the gel composition at the contact portion in the connection process is easy. Ingredients are commonly used.

Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited by these examples.

Examples 1-10 and Comparative Examples 1-2

Base oils (mineral oil, Ultra 6 of Soil, Cas No. 64742-54-7, crystallization temperature of -18 ° C) and synthetic oils (Synthetic oil-PAO, PAO 6 from Chevron, Cas No. 68037-01-4, SEP polymer (using Shellton 1701, Cas No. 78648-89-5, manufactured by Shell) was added to a crystallization temperature of -68 ° C, and the mixture was heated and stirred at 120 to 140 ° C to disperse and disperse the SEP polymer in base oil. After cooling to a state, a microsphere (using Expancel 051DE, Cas No. 30376-85-1 from HAEx Chemical) and an antioxidant (using Naugard PS 48 from Uniroyal Chemical) was added thereto, followed by stirring. After the uniformly dispersed to prepare a low-density optical cable filler to maintain a vacuum state is prepared by removing the air bubbles mixed during stirring. On the other hand, as a comparative example, the composition without adding the pour point depressant was prepared in the same manner.

Table 1 shows the case where the polyalphaolefin oil, which is a low flow point oil, is not blended, and Table 2 shows the case where the polyalphaolefin oil, which is a low flow point oil, is blended. Cone penetration at -40 ° C and -50 ° C was compared with the comparative example.

In the following table, parts (P) and% represent parts by weight and% by weight, respectively.

division Comparative Example 1 Example 1 Example 2 Example 3 Example 4 Example 5 Mineral Oil -18 ℃ 91.5% 91.5% 91.5% 91.5% 91.5% 91.5% SEP (G1701)  8.5% 8.5%  8.5%  8.5% 8.5%  8.5% Antioxidant (PS 48) 0.5 P 0.5 P 0.5 P 0.5 P 0.5 P 0.5 P Pour point depressant (V386) - 0.1 P 0.3 P 0.5 P 1.0 P 1.5 P Drop Point (℃) 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ Viscosity
(25 ° C, mPa.s) D = 6S ^-1 12,500 12,500  12,500 12,500 12,500 12,500 D = 50S ^-1 3,650 3,650  3,650  3,650  3,650  3,650 D = 200S ^-1 2,500 2,500  2,500 2,500 2,500 2,500 Cone breaking road
(Cone Penetration) 25 ℃ 435 435 435 435 435 435 -40 ° C 165 200 224 235 254 254 Oil Separation
(100 ℃ * 24hrs) 0 0 0 0 0 0 O.I.T (190 ° C, min) 50 or more 50 or more 50 or more 50 or more 50 or more 50 or more Optical fiber discoloration test
(85 ℃ * 5 days) Discoloration Discoloration Discoloration Discoloration Discoloration Discoloration

division Comparative Example 2 Example 6 Example 7 Example 8 Example 9 Example 10 Mineral Oil -18 ℃ 51.5% 51.5% 51.5% 51.5% 51.5% 51.5% PAO-6 -68 ℃ 40% 40% 40% 40% 40% 40% SEP (G1701)  8.5% 8.5%  8.5%  8.5% 8.5% 8.5% Antioxidant (PS 48) 0.5 P 0.5 P 0.5 P 0.5 P 0.5 P 0.5 P Pour point depressant (V386) - 0.1 P 0.3 P 0.5 P 1.0 P 1.5 P Drop Point (℃) 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ Viscosity
(25 ° C, mPa.s) D = 6S ^-1 10,000 10,000  10,000 10,000 10,000 10,000 D = 50S ^-1 2,850 2,850  2,850  2,850  2,850  2,850 D = 200S ^-1 2,500 2,100  2,100 2,100 2,100 2,100 Cone breaking road 25 ℃ 445 445 445 445 445 445 -40 ° C 200 235 265 295 295 295 Oil separation (100 ℃ * 24hrs) 0 0 0 0 0 0 O.I.T (190 ° C, min) 50 or more 50 or more 50 or more 50 or more 50 or more 50 or more Optical fiber discoloration test
(85 ℃ * 5 days) Discoloration Discoloration Discoloration Discoloration Discoloration Discoloration

Table 1, double,

* Viscosity; Brookfild Viscometer DV-III

* O.I.T; Oxidative Induction Time

It can be seen from the Tables 1 and 2 that the addition of the pour point depressant regardless of whether the synthetic oil is blended significantly increases the cone penetration. These results indicate that the blending amount of the synthetic oil can be reduced by blending the pour point depressant.

In addition, as shown in the table, it is possible to prepare a gel composition without using a pour point depressant, but in this case, the content of synthetic oil (PAO) should be added about 70% or more, in which case the manufacturing cost becomes too high. .

Examples 13-14 and Comparative Examples 3-6

In the same manner as in Example 1, 2 with the components and contents shown in Table 2 below. Except for microspheres in Examples, each component is the same as Example 1, 2.

division Comparative Example 3 Example 11 Comparative Example 4 Example 12 Comparative Example 5 Example 13 Comparative Example 6 Example 14 Mineral oil 11.2 11.2 33.6 33.6 47.8 47.8 47.7 47.7 Synthetic oil 78.8 78.8 56.1 56.1 42.2 42.2 42.1 42.1 SEP polymer
(G 1701) 6 6 6 6 6 6 6.7 6.7 Microspheres
(Expencel051 DET) 3.3 3.3 3.3 3.3 3 3 2.5 2.5 Antioxidant
(PS 48) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Pour point depressant
(V 386) - 0.1 - 0.5 - 0.5 0.5 Density (25 ℃) g / ml 0.41 0.41 0.41 0.41 0.42 0.42 0.45 0.45 Dropping point (℃) 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ 210 ↑ Cone breaking road 25 ℃ 430 430 420 420 435 435 420 420 -40 ° C 270 285 225 240 215 235 225 240 Viscosity
(25 ° C, mPa.S) D = 6 ^S-1 39,450 39,400 47,100 47,050 42,096 42,096 43,392 43,392 D = 10 ^S-1 29,550 29,500 35,250 35,200 31,000 30,950 32,385 32,385 D = 50 ^S-1 12,920 12,900 14,800 14,795 13,350 13,300 13,239 13,239 D = 200 ^S-1 5,760 5,750 6,200 6,150 6,185 6,100 6,516 6,516 Oil separation
(100 ℃ * 24hrs) 0 0 0 0 0 0 0 0 OIT
(190 ℃, min) 50 ↑ 50 ↑ 50 ↑ 50 ↑ 50 ↑ 50 ↑ 50 ↑ 50 ↑ Optical fiber discoloration test
(85 ℃ * 5 days) Discoloration Discoloration Discoloration Discoloration Discoloration Discoloration Discoloration Discoloration

As shown in the above examples, even when low-density microspheres were contained in the gel composition for low-density type optical cables, it was found that the addition of the pour point depressant increased the cone penetration.

Claims (3)

In the low density optical fiber gel composition consisting of a base oil, a gelling agent,
A gel composition for a low density optical cable comprising a pour point lowering agent comprising 0.1 to 1.6 parts by weight relative to the base oil component, and a microsphere having a specific gravity of 0.023 to 0.028 so that the density of the gel composition is 0.380 to 0.550. The gel composition for a low density type optical cable according to claim 1, wherein the base oil is mineral oil alone or a mixture of mineral oil and synthetic oil. The gel composition of claim 1 or 2, wherein the pour point depressant is Infinium V 386 or 382 (Infineum V386 / V382) or VISCOPLEX 1-330 (RohMax GmbH & Co.).