WO2012024902A1

WO2012024902A1 - Composite fiber reinforcement core, preparation method thereof and application in optic drop cable

Info

Publication number: WO2012024902A1
Application number: PCT/CN2011/070205
Authority: WO
Inventors: 高欢; 顾白; 朱天; 武强
Original assignee: 苏州恒玄电子科技有限公司
Priority date: 2010-08-23
Filing date: 2011-01-12
Publication date: 2012-03-01
Also published as: CN102127239A; CN102127239B

Abstract

A composite fiber reinforcement core, preparation method thereof and application in optic drop cable are provided. The composite fiber reinforcement core comprises: polyethylene fiber bundle and a modified polyester copolymer covered on its surface. The modified polyester copolymer comprises the following components of weight percent: polyethylene terephthalate 5-15%, PBT glass fiber 55-65%, maleic anhydride modified polyolefin 10-15%, polyethylene 15-20%. Said composite fiber reinforcement core has the following advantages: simple and compact structure, low production cost, high mechanical strength and excellent flexibility.

Description

Composite fiber reinforced core, preparation method thereof and application in introducing optical cable

The present invention relates to fiber optic cable technology, and more particularly to a composite fiber reinforced core, a method of making the same, and use in the introduction of an optical cable. Background technique

Indoor fiber optic cable is a fiber optic cable that is used on a large scale in the FTTH (Fiber To The Home) network. It is also suitable for other fiber access such as FTTO (Fiber To The Off ice) and FTTB (F Users of networks such as iber To The Bui lding, fiber-to-the-floor) introduce fiber optic cables. Indoor fiber optic cable is mainly used in the indoor wiring stage. Indoor wiring is the most complicated part of the entire fiber access engineering, and it has high requirements on the mechanical properties such as bending performance and tensile performance of the cable.

Currently used indoor optical cable, the reinforcing core is mainly made of glass fiber reinforced core (FRP) and aramid fiber reinforced core (KFRP). Their mechanical properties are shown in Table 1. Very few steel wires are used as reinforcing cores. The core itself has a large weight and a too large bending radius. At the same time, due to its metallic characteristics, it cannot be prevented from lightning strikes and has basically withdrawn from the market.

Table 1 Different types of reinforcing core mechanical performance indicators

The structure of the glass fiber reinforced core which is widely used at present is as shown in Fig. 1, which is filled with an epoxy resin 6 between a plurality of glass fibers 7, and completely covered with the glass fibers 7. Glass fiber reinforced core (FRP) fiber optic cable has the advantages of tensile strength, corrosion resistance and lightning strike resistance due to its reinforcing core. However, epoxy resin ensures the relative position between multiple glass fibers is fixed, but the relative displacement cannot occur. , affecting the anti-folding performance of the reinforcing core, thereby further affecting the flexibility of the butterfly-introduced fiber. And glass The glass fiber reinforced core is easy to break and heavy, and it is also a fatal weakness. It is easy to break due to being bent and knotted during indoor wiring construction, resulting in complete loss of the reinforcing core.

Aramid fiber reinforced core (KFRP) has strong tensile strength and high flexibility, is not easily broken, and has excellent mechanical properties (mechanical properties are shown in Table 1), but the raw material aramid fiber is very demanding. This kind of aramid fiber is currently monopolized by a few countries, and the production cost is relatively high, which is rarely used in indoor optical cables. Summary of the invention

The invention provides a composite fiber reinforced core to solve the defects in the prior art, and the composite fiber reinforced core obtained by the improvement of the composition thereof has the advantages of simple structure, low production cost, high mechanical strength, and high mechanical strength. Excellent flexibility.

The present invention provides a composite fiber reinforced core comprising a bundle of polyethylene fibers and a modified polyester copolymer coated on the surface thereof, the modified polyester copolymer comprising the following components by weight:

Polybutylene terephthalate ( PBT ) 5-1 0 % ;

PBT glass fiber 55-65%;

Maleic anhydride modified polyolefin 1 0-15%;

Polyethylene 15-20%.

Further, the polyethylene fiber bundle is preferably a high-strength high-modulus polyethylene fiber bundle. The high-strength high-modulus polyethylene fiber of the present invention refers to a polyethylene fiber which is recognized in the art and has a fiber strength of more than 1 7. 820 g/d and a modulus of 500 g/d or more.

Further, the diameter of the polyethylene fiber bundle used in the present invention: 0. 2-0. 5匪; density: 0. 97g/cm ³ ; strength: > 30g / d; modulus: > 1 000g / d; Elongation: < 3 %.

Another object of the present invention is to provide a method for preparing a composite fiber reinforced core. The processed product is used for the introduction of an optical cable by a scientifically succinct process, and has the advantages of high strength and good flexibility.

The invention provides a method for preparing a composite fiber reinforced core, comprising the following steps: (1), the above weight percentage components are stirred and hooked to obtain a blended material; the mixing process may be a plastic color mixing machine;

(2), the blending material obtained in step (1) is placed in an extruder drying drum for drying, the time is 3-4 hours, and the temperature is controlled at 120-130 °C;

(3) passing the bundle of polyethylene fibers through the core, and then placing the core in the mold sleeve; and preparing the blended material in the step (2) through a screw extruder to form a modified polyester copolymer, and then The modified polyester copolymer is extruded by a control screw extruder, and the modified polyester copolymer is coated and extruded on the surface of the polyethylene fiber bundle to finally obtain a composite fiber reinforced core. The polyester copolymer has the advantages of high temperature resistance and folding resistance;

Further, the extruder has a screw diameter Φ of 35 匪 -50 匪 to ensure effective control of the diameter of the reinforcing core during the production process.

Further, the parameters of the extruder are controlled as follows: core diameter: 0. 3-0. 5mm; die sleeve diameter: 0. 4-0. 6mm; processing temperature: first Zone 200-230 °C, second zone 250-270 °C, third zone 260 _ 280 °C, fourth zone 270-280 °C, fifth zone 260-280 °C; screw speed: 10-80RPM; Traction speed: 500-600RPM; line speed: 100-160m/min, to ensure that the modified polyester copolymer can be smoothly extruded, and evenly coated on the surface of the polyethylene fiber bundle, so that the obtained reinforcing core meets skills requirement.

Further, after the modified polyester copolymer is coated and extruded on the surface of the polyethylene fiber bundle, it is cooled by a cold water tank and blow-dried, and finally wound up in a dry and clean environment.

Another object of the present invention is to provide the above-mentioned application of the composite fiber reinforced core in the introduction of the optical cable, overcome the problems of poor bending performance of the current optical cable, and realize the mechanical strength such as tensile strength and pressure resistance of the optical cable. The advantage of good flexibility of the cable.

The present invention also provides a butterfly-shaped drop cable, comprising: a composite fiber reinforced core, a butterfly outer sheath and an optical fiber, wherein the butterfly outer sheath is provided with an optical fiber in the middle, and the butterfly outer sheath has two wings respectively The composite fiber reinforced core is provided.

Further, the optical fiber is a single mode fiber of the ITU-T G.657 standard, and the whole chromatography is performed by chromatography. Logo.

Further, the butterfly outer sheath is made of a flame retardant polyolefin.

The composite fiber reinforced core of the invention, the preparation method thereof and the application in the introduction of the optical cable have the following advantages compared with the prior art:

(1) Ordinary polyethylene fiber bundles do not have temperature resistance, and melt and break at temperatures above 80 °C. After the modified polyester copolymer is coated, the composite fiber reinforced core can withstand the high temperature of 150-180 ° C without melting, thereby ensuring smooth passage of the machine head during the preparation of the optical cable (ie, the raw material in the drying cylinder is extruded by the screw) Area) without being blown (head temperature is around 140 °C).

(2) The composite fiber reinforced core has a tensile strength of 1200-1500 MPa and a tensile modulus of more than 55 GPa, which is far greater than the tensile strength and tensile modulus of the current glass fiber reinforced core. The butterfly-shaped I-in cable has high mechanical strength.

(3) In the manufacturing process, the glass fiber reinforced core is filled with epoxy resin between the glass fibers, and completely covered with the glass fibers, so that the relative positions between the glass fibers remain fixed, and the relative The displacement affects the bending properties of the reinforcing core, further affecting the softness of the entire butterfly-introducing cable. The composite fiber reinforced core of the present invention is coated on the surface of the high-strength high-modulus polyethylene fiber bundle with a high-temperature resistant, anti-folding modified polyester copolymer, so that the internal fibers are not restrained by the coating layer, and The relative displacement occurs so that the butterfly-introducing cable finally produced using the reinforcing core is flexible and easy to bend. DRAWINGS

The drawings are intended to provide a further understanding of the invention, and are intended to be a part of the description of the invention. In the drawings: Figure 1 is a schematic cross-sectional view of a conventional reinforcing core;

2 is a schematic cross-sectional view showing a composite fiber reinforced core according to Embodiment 1 of the present invention;

FIG. 3 is a schematic cross-sectional view of a super-flexible folding butterfly-shaped lead-in cable according to Embodiment 1 of the present invention. With reference to the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows: 1 - fiber 2 - composite fiber reinforced core 3-butterfly outer sheath

4-polyethylene fiber bundle 5-modified polyester copolymer 6-epoxy resin

7-glass fiber

The technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Some embodiments, rather than all of the embodiments, are invented. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

The composite fiber reinforced core provided by the embodiment of the present invention comprises a polyethylene fiber bundle and a modified polyester copolymer coated on the surface thereof, and the modified polyester copolymer comprises the following components by weight: poly-p-phenylene Butylene phthalate ( PBT ) 5-1 5 %;

PBT glass fiber 55-65%;

Maleic anhydride modified polyolefin 1 0-15%;

Polyethylene 15-20%.

The PBT can be B6550LN and B4500 produced by BASF, Germany; the PBT glass fiber can be B4300G2, B4300G4, B4300G6 produced by BASF, Germany, and the maleic anhydride modified polyolefin is developed by Shanghai Risheng New Technology. Produced by the company, the polyethylene is produced by Yangzi Petrochemical.

The preparation method of the composite fiber reinforced core comprises the following steps:

(1), the above weight percentage components are stirred and mixed with a plastic color mixing machine to obtain a blended material; (2), the blended material obtained in the step (1) is placed in an extruder drying cylinder for baking. Dry treatment, the time is 3-4 hours, the temperature is controlled at 120-1 30 °C;

(2) The mold core is placed in a mold having a diameter of 0. 4-0. 5 ;; The dry blended material passes through the screw extruder Forming a modified polyester copolymer, and then controlling the screw extruder to extrude the modified polyester copolymer, so that the modified polyester copolymer is coated and extruded on the surface of the polyethylene fiber bundle, and finally a composite fiber is obtained. Reinforce the core.

Embodiment 1

2 is a schematic cross-sectional view of a composite fiber reinforced core according to a first embodiment of the present invention; and FIG. 3 is a schematic cross-sectional view of a super-flexible folding butterfly-shaped optical fiber cable according to Embodiment 1 of the present invention.

Preparation of modified polyester copolymer: plastic blender with raw material weight percentage of PBT: 10%, PBT glass fiber: 60%, maleic anhydride modified polyolefin 9804: 15%, polyethylene 5000s: 15% The temperature is controlled at 120-130 °C. The uniformly dried blended material is passed through a φ35 螺杆 screw extruder to form a modified polyester copolymer, and the screw extruder is provided with a heating unit to achieve the necessary polymerization temperature of the blended material.

Preparation of composite fiber reinforced core 2: Fiber diameter: 0. 2-0. 5mm; Fiber density: 0. 97g/cm ³ ; Fiber strength: >30g/d; Fiber modulus: >1000g/d; Fiber elongation The mold core of the diameter of 0. ⁴ _0. 6 之中 is placed in the mold sleeve having a diameter of 0.3 to 0.5 匪. Then, the Φ 35 匪 screw extruder was controlled to extrude the modified polyester copolymer 5 so that the modified polyester copolymer 5 was coated and extruded on the surface of the high-strength high-modulus polyethylene fiber bundle 4 (as shown in Fig. 2). The wrapped polyethylene fiber bundle 4 is cooled by a cold water tank and blow-dried, and finally wound up in a dry and clean environment. During the extrusion process, the parameters of the Φ 35匪 extruder are controlled as follows: 200-230°C in the first zone, 250-270°C in the second zone, 260-280°C in the third zone, and 270-280°C in the fourth zone. The fifth zone is 260-280 °C. Screw speed: 10-80RPM, line speed: 100-160m/min _{o The} first area is the screw rear area; the second area is the screw middle area; the third area is the screw front area; the fourth area is the neck; The fifth zone is the machine head (ie, the coating point), and the mechanical properties of the composite fiber reinforced core 2 prepared by the above method are shown in Table 2.

Table 2 Mechanical properties of composite fiber reinforced core

Diameter tensile strength tensile modulus of elasticity elongation elongation resistance surface temperature

( mm ) ( MPa ) ( GPa ) ( % ) ( N ) ( °C )

0. 4-0. 5 1200-1500 55-60 3 58-67 150-180 Compared with the glass fiber reinforced core (FRP) and the aramid fiber reinforced core (KFRP) in Table 1, the tensile strength and tensile modulus of the composite fiber reinforced core 2 are improved to varying degrees (as shown in Table 2). Shown), the composite fiber reinforced core 2 has both high mechanical strength and excellent flexibility.

Butterfly-shaped cable, also known as indoor butterfly cable, leather cable, indoor cable, is a fiber optic cable that is widely used in FTTH (Fiber To The Home) networks. It is also suitable for other fiber access. Users of networks such as FTT0 (Fiber To The Office) and FTTB (Fiber To The Building) have introduced fiber optic cables. Its cross-section is like a butterfly, so it is named butterfly-shaped cable (also known as "8" cable).

The invention utilizes the above composite fiber reinforced core 2 to manufacture a super-flexible folding butterfly-shaped introduction cable: a single-mode optical fiber conforming to the ITU-T G.657 standard is selected, and the chromatogram is marked by a full-color medium. The outer sheath material for the optical cable adopts a butterfly outer sheath 3, the butterfly outer sheath 3 is a thermoplastic low-smoke halogen-free flame-retardant polyolefin cable material of 90°C, and the butterfly outer sheath 3 can also be selected from thermoplastic low-smoke and non-resistance. The polyolefin cable material and the environmental protection drying cylinder are dried, and the temperature is controlled at about 80 °C, and the time is about 2 hours.

One disk of fiber 1 and two disks of the above composite fiber reinforced core 2 are placed on the active pay-off frame of the Φ50匪 extruder, and the tension is controlled as follows: the composite fiber reinforced core 2 is 1.2N+0.2N, and the fiber 1 is 1N±0.2. N. The optical fiber 1 passes through the small hole in the center of the butterfly cable mold, and the two composite fiber reinforcing cores 2 are parallel to the central optical fiber 1, and are symmetrically placed on both sides of the optical fiber 1 and passed through the butterfly optical cable mold to control the Φ50匪 extruder extrusion optical cable. The outer sheathing material completely covers the surface of the optical fiber 1 and the composite fiber reinforcing core 2 to form a butterfly-introducing optical cable. During the cable forming process, the parameters of the Φ50匪 extruder are controlled as follows: First zone (rear area of screw) 130±5°C, second zone (middle zone of screw) 140±5°C, third zone (rear area of screw) 155±5°C, fourth zone (neck) 165 ± 5°C, fifth zone (head) 165±5°C, line speed: <80m/min _o Super soft resistance provided by this embodiment The structure of the cross-section of the butterfly-shaped cable is shown in Fig. 3. The composite fiber reinforcing core 2 is on both sides, and the fiber 1 is in the middle. The number of the optical fibers 1 may be one, two or four.

The super-flexible folding butterfly-shaped introduction cable provided by the embodiment adopts the anti-folding composite fiber reinforced core 2 instead of the glass fiber reinforced core, so that the manufactured optical cable satisfies both the mechanical strength requirement and the excellent Softness.

Embodiment 2

Preparation of modified polyester copolymer: Plastic color mixing machine with raw material weight percentage of PBT: 10%, PBT glass fiber: 60%, maleic anhydride modified polyolefin 5001: 10%, polyethylene 5306: 20% The stirring temperature is controlled at 120-130 °C. The uniformly dried blend material was extruded through a φ35 crucible to form a modified polyester copolymer.

The fiber has a fiber density of 0. 25-0. 4匪; fiber density is 0. 97g / cm ³ ; fiber strength > 30g / d; fiber moduli of 800 g/d and 1000 g/d, respectively; fiber elongation: < 3%. 5毫米的模具套, The core is placed in a mold having a diameter of 0. 6mm. The Φ 35 匪 screw extruder was then controlled to extrude the modified polyester copolymer so that the copolymer was extrusion coated on the surface of the high strength high modulus polyethylene fiber bundle. The coated polyethylene fiber bundle is cooled by a cold water tank and blow-dried, and finally wound up in a dry and clean environment. During the extrusion process, the parameters of the Φ 35匪 extruder are controlled as follows: 200-230°C in the first zone, 250-270°C in the second zone, 260-280°C in the third zone, and 270-280°C in the fourth zone. The fifth zone is 260-280 °C. Screw speed: 10-80RPM, line speed: 100-160m/min. The mechanical properties of the composite fiber reinforced core prepared by the above method are shown in Table 3.

Table 3 Mechanical properties of composite fiber reinforced core

2N。 The optical fiber is 1N±0. 2N, the optical fiber is 1N±0. 2N, the optical fiber is 1N±0. 2N, and the optical fiber is 1N±0. 2N. The optical fiber passes through the small hole in the center of the butterfly cable mold, and the two reinforcing cores are parallel to the central optical fiber, and are symmetrically placed on the optical fiber. Side and through the butterfly cable mold, the Φ50匪 extruder is controlled to extrude the outer sheath material of the cable to completely cover the surface of the fiber and the reinforcing core to form a butterfly-introducing cable. During the cable forming process, the parameters of the Φ50匪 extruder are controlled as follows: The first zone (the screw rear zone) 1 ³ 0±5°C, the second zone (the screw middle zone) 1 ⁴ 0±5°C, the third zone ( Screw rear area) 1 ⁵⁵ ±5°C, fourth zone (neck) 1 ⁶⁵ ±5°C, fifth zone (head) 165±5°C, line speed: 80m/min. The optical cable overcomes the problems of poor bending performance of the current optical cable, and achieves the advantages of good flexibility of the optical cable while ensuring mechanical strength such as tensile strength and compression resistance of the optical cable.

It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced. The modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request

A composite fiber reinforced core comprising a polyethylene fiber bundle and a modified polyester copolymer coated on a surface thereof, the modified polyester copolymer comprising the following components by weight: Butylene phthalate 5-15%;

PBT glass fiber 55-65%;

Maleic anhydride modified polyolefin 10-15%;

Polyethylene 15-20%.

The composite fiber reinforced core according to claim 1, wherein the polyethylene fiber bundle is a high-strength high-modulus polyethylene fiber bundle.

The composite fiber reinforced core according to claim 1 or 2, wherein the polyethylene fiber bundle has a diameter of 0.2 to 0.5 mm, a density of 0.97 g/cm ³ , and a strength of >30 g/d; Amount: >1000g/d; Elongation: <3%.

A method of preparing a composite fiber reinforced core according to any one of claims 1 to 3, which comprises the steps of:

(1), the above weight percentage components are stirred and hooked to obtain a blended material;

(2), the blending material obtained in step (1) is placed in an extruder drying cylinder for drying, the time is 3-4 hours, and the temperature is controlled at 120-130 ° C;

(3) passing the bundle of polyethylene fibers through the core, and then placing the core in the mold sleeve; and preparing the modified polyester copolymer by passing the blended material in the step (2) through a screw extruder Then, the modified polyester copolymer is controlled by a screw extruder, and the modified polyester copolymer is coated and pressed on the surface of the polyethylene fiber bundle to finally obtain a composite fiber reinforced core.

The preparation method according to claim 4, wherein the extruder has a screw diameter Φ of 35 mm - 50 mm ₀

6. The preparation method according to claim 4 or 5, wherein the parameters of the extruder are controlled as follows: core diameter: 0.3-0.5 匪; die sleeve diameter: 0.4-0.6 mm; processing temperature: One zone 200-230 °C, the second zone 250-270 °C, the third zone 260-280 °C, the fourth zone 270-280 °C, the fifth zone 260-280 °C; screw speed: 10-80RPM ; Traction speed: 500-600 RPM; Line speed: 100-160m/min _o

The preparation method according to claim 4, wherein the modified polyester copolymer

A butterfly-shaped fiber-optic cable, comprising the composite fiber reinforced core, the butterfly outer sheath and the optical fiber according to any one of claims 1 to 3, wherein the butterfly outer sheath is provided with an optical fiber in the middle. The composite fiber reinforcing core is disposed in each of the wings of the butterfly outer sheath.

The butterfly drop cable according to claim 8, wherein the optical fiber is a single mode fiber of the ITU-T G.657 standard.

10. The butterfly drop cable according to claim 8, wherein the butterfly outer sheath material is a halogen-free flame-retardant polyolefin.