CN112213818A

CN112213818A - h-GI-POF high-temperature optical fiber and preparation method thereof

Info

Publication number: CN112213818A
Application number: CN201910624061.8A
Authority: CN
Inventors: 翁德喜; 方民锋; 冈本吉行; 杜启明; 小池康太郎; 弗兰克-米喀什; 提蛮西-默克尔; 何振杰; 张�浩; 小池康博
Original assignee: China Fujian Optical Fiber Technology Co ltd
Current assignee: China Fujian Optical Fiber Technology Co ltd
Priority date: 2019-07-11
Filing date: 2019-07-11
Publication date: 2021-01-12

Abstract

The invention belongs to the technical field of optical fibers, and particularly relates to an h-GI-POF high-temperature optical fiber and a preparation method thereof. The h-GI-POF high-temperature optical fiber comprises an inner core layer and an outer skin layer, wherein the inner core layer and the outer skin layer are arranged in a concentric structure, the inner core layer and the outer skin layer are formed by copolymerizing perfluorodioxolane and perfluorodioxin bicyclononane into high polymers with different refractive indexes, the refractive index of the inner core layer is greater than that of the outer skin layer, the inner core layer is formed by integrally forming 5 core layers with the refractive indexes gradually reduced from a core to the outside, the outer skin layer is formed by a single-layer skin layer, so that the transparency of the optical fiber reaches more than 98%, the glass transition temperature Tg exceeds 150 ℃, and the optical fiber is suitable for ultrahigh-speed communication; compared with the prior art SI-POF, the invention uses 6 layers of core materials, each core layer is the gradual change refractive index, so that the transmission delay of incident light is shorter than that of the common SI-POF, the signal transmission bandwidth is larger, and the transmission speed is faster.

Description

h-GI-POF high-temperature optical fiber and preparation method thereof

Technical Field

The invention belongs to the technical field of optical fibers, and particularly relates to an h-GI-POF high-temperature optical fiber and a preparation method thereof.

Background

Optical fiber (optical fiber) generally refers to a transparent, few microns to several hundred microns diameter fiber capable of conducting light waves and various optical signals.

Conventional optical fibers are generally used for optical communication to transmit signals over long distances, and have a signal transmission speed much higher than that of metal cables and wires, so that the optical fibers can replace the metal cables. Another factor that determines the replacement of metal cables with optical fibers is that optical fibers have little loss to the transmitted signal; the optical fiber is not affected by electromagnetic interference that would otherwise seriously disturb the metallic wire. A fiber typically has a transparent core (core) with a slightly higher optical index surrounded by a cladding (cladding) with a slightly lower refractive index, which results in a structure that is totally reflective of incident light, and thus the optical signal is confined to the fiber for transmission by total reflection. An optical fiber that allows transmission paths of a variety of incident light rays is called a multimode fiber (MMF), whereas a Single Mode Fiber (SMF) that allows only one path. The core layer of multimode optical fiber (MMF) is typically a large core with a diameter >50 μm for short-range communication; single mode optical fibres (SMFs) typically have a core diameter of 8-10 μm and are commonly used for long range (> 2000 m) communications.

One notable issue with fiber optic communications is to minimize the number of connections between fibers, i.e., connections that are tight and convenient, to minimize the resulting optical loss. Glass optical fibers are widely used for long-distance high-speed communication systems due to their excellent performance, but the connection of glass optical fibers is much more complicated than that of metal cables, the connection loss is particularly important and complicated due to the small cross section of Glass Optical Fibers (GOF), and in applications requiring permanent connection, glass optical fibers are usually mechanically fused together; and glass fibers (GOFs) are very susceptible to breakage, especially during bending corner motions during handling and installation, and splice connections are currently used to solve this problem, which in turn increases the cost of handling glass fibers. Both of these disadvantages prevent the use of glass fiber at the end of modern high-speed networks and data communications, and therefore, people must also use metal wires or coaxial cables for short-distance connections, such as Fiber To The Home (FTTH), smart cars, offices, building communications, etc. The ultra-low speed of metal cables is the bottleneck of modern high-speed communications.

Researchers have been working for many years to develop softer, higher speed high polymer optical fibers to replace metal cables. Since scientists in the last 60 s demonstrated the important role of high polymer optical fiber (POF, or polymer plastic optical fiber) in the modern signal communication field, POF has been increasingly used in the modern signal communication field, especially in LAN, data center, large airplane manufacturing, smart car, smart home, game entertainment, medical, and so on. The POF can cooperate with the GOF to form a true high-speed communication network instead of metal wires. Modern high polymer optical fibers typically use Polystyrene (PS) or Polymethylmethacrylate (PMMA) as the core material, and the sheath is made of a polymer with a lower refractive index, forming a step-up polymer optical fiber (SI-POF). PMMA is highly transparent and waterproof, and is suitable for short-range optical communication. Although these fibers are low cost, their optical losses and transmission speed drawbacks greatly limit their potential to replace metal cable wires. Therefore, there is a wide potential market demand for developing polymer optical fibers for ultra-high speed communications.

Disclosure of Invention

The invention provides an h-GI-POF high-temperature optical fiber and a preparation method thereof, aiming at solving the problems that the existing glass optical fiber is small in core diameter, complex in connection and high in cost, and the communication speed of a metal cable is ultralow.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a method for preparing h-GI-POF high temperature optical fiber,

s1: preparing six high polymers with different refractive indexes;

s101: to the reactor was added n moles of monomer M8A: perfluoro-2-methyl-4, 5-methoether-1, 3-dioxolane, M moles of monomer M8E: perfluoro-3-methylene-2, 4-dioxine bicyclo [4,3,0] nonane, an initiator, wherein n: m =35-90: 10-65;

s102: stirring and introducing nitrogen for cleaning, and after cleaning, decompressing and heating the reaction kettle for polymerization reaction;

s103: after the reaction is finished, dissolving the reactant by using a solvent hexafluorobenzene, then precipitating by using a solvent chloroform, and repeatedly dissolving and precipitating to obtain a high polymer X;

the high polymer X is obtained by high polymer X1, high polymer X2, high polymer X3, high polymer X4, high polymer X5 and high polymer X6 according to different proportions of monomer M8A and monomer M8E;

s104: respectively blending high polymer X1, high polymer X2, high polymer X3, high polymer X4, high polymer X5 and high polymer X6 with penetrant in a mixer to obtain six high polymers Y1, Y2, Y3, Y4, Y5 and Y6 with different refractive indexes;

s2: injecting six high polymers with different refractive indexes into a co-extrusion system to manufacture the h-GI-POF high-temperature optical fiber;

the co-extrusion system comprises a co-extrusion die and six extrusion heads, wherein a first flow passage, a second flow passage, a third flow passage, a fourth flow passage, a fifth flow passage and a sixth flow passage are sequentially and concentrically distributed from the center of the co-extrusion die to the outside, a heating gradual change area is arranged on the co-extrusion die, and the extrusion heads are correspondingly butted with the flow passages one by one;

injecting the molten fluids of the six high polymers into the first flow channel, the second flow channel, the third flow channel, the fourth flow channel, the fifth flow channel and the sixth flow channel in a one-to-one correspondence mode according to the refractive indexes of the six high polymers from large to small through the extrusion head so as to respectively generate a first core layer, a second core layer, a third core layer, a fourth core layer, a fifth core layer and an outer skin layer; and the first core layer, the second core layer, the third core layer, the fourth core layer, the fifth core layer and the outer skin layer gradually form the h-GI-POF high-temperature optical fiber through penetrating and diffusing of a penetrating agent in the heating gradual change region.

Further, in the step S101, the initiator includes perfluorodibenzoyl peroxide, and the mass percentage of the initiator is 0.05-0.15%.

Further, the reaction pressure of the reaction kettle in the step S102 is 0.35-0.95 atmosphere, the reaction temperature is 60-90 ℃, and the reaction time is 20-40 h.

Further, after the step S103, the obtained high polymer X is dried in a decompression oven with the pressure of 0.35-0.95 atmosphere and the temperature of 90-105 ℃ for 20-30 h.

Further, the blending sequence of step S104 in the mixer is: firstly, mixing and melting a high polymer X at the temperature of 230-270 ℃; after melting, the temperature is reduced by 5-10 ℃, the penetrant is added while the mixer rotor runs, and then the high polymer of each core layer is extruded after mixing for 5-10 min.

Further, the penetrating agent comprises 1, 3-dibromo tetrafluorobenzene, and the mass percentage of the 1, 3-dibromo tetrafluorobenzene is 0-5%.

An h-GI-POF high-temperature optical fiber comprises an inner core layer and an outer skin layer, wherein the inner core layer and the outer skin layer are arranged in a concentric structure, the refractive index of the inner core layer is larger than that of the outer skin layer, the inner core layer and the outer skin layer are composed of high polymers with different refractive indexes, and the high polymers are formed by copolymerizing perfluorodioxolane and perfluorodioxin-bicyclononane, and the h-GI-POF high-temperature optical fiber is prepared by applying the preparation method of the h-GI-POF high-temperature optical fiber according to any one of claims 1 to 6.

Furthermore, the inner core layer is formed by integrally forming 5 core layers with the refractive index gradually reduced from the core to the outside, and comprises a first core layer, a second core layer, a third core layer, a fourth core layer and a fifth core layer, wherein the fifth core layer, the fourth core layer, the third core layer, the second core layer and the first core layer have the gradient refractive index of 1.3512-1.3635.

Further, the outer skin layer is composed of a single skin layer, and the refractive index of the outer skin layer is 1.3473.

Furthermore, the optical loss of the h-GI-POF high-temperature optical fiber is 19-31dB/km, and the bandwidth is not less than 760 MHz-km.

The invention provides an h-GI-POF high-temperature optical fiber, which comprises an inner core layer and an outer skin layer, wherein the inner core layer and the outer skin layer are arranged in a concentric structure, the inner core layer and the outer skin layer are composed of high polymers with different refractive indexes, the high polymers are formed by copolymerizing perfluorodioxolane and perfluorodioxin bicyclononane, the refractive index of the inner core layer is greater than that of the outer skin layer, the inner core layer is formed by integrally molding 5 core layers, the refractive indexes of the core layers are gradually reduced from the core layer to the outside, the outer skin layer is composed of a single skin layer, the transparency of the outer skin layer reaches more than 98%, the glass transition temperature Tg exceeds 150 ℃, and the optical fiber is suitable for ultrahigh-speed communication; compared with the SI-POF in the prior art, the invention uses 6 layers of core materials, and each core layer has the gradually-changed refractive index, so that the transmission delay of incident light is shorter than that of the common SI-POF, the signal transmission bandwidth is larger, and the transmission speed is higher.

Drawings

FIG. 1 is a schematic structural diagram of an h-GI-POF high-temperature optical fiber;

FIG. 2 is a cross-sectional view of an h-GI-POF high temperature optical fiber before molding;

FIG. 3 shows a reaction scheme of a high polymer X;

FIG. 4 is a DSC curve analysis chart of high polymer Y1-Y6;

FIG. 5 is a schematic diagram of the structure of a coextrusion system.

Detailed Description

The technical solutions in the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments.

As shown in fig. 1 and 2, an h-GI-POF high temperature optical fiber includes an inner core layer 10a and an outer skin layer 10b, the inner core layer 10a and the outer skin layer 10b are concentrically arranged, the refractive index of the inner core layer 10a is greater than that of the outer skin layer 10b, the inner core layer 10a and the outer skin layer 10b are composed of high polymers with different refractive indexes, and the high polymers are formed by copolymerizing perfluorodioxolane and perfluorodioxin bicyclononane, and the h-GI-POF high temperature optical fiber is manufactured by applying the following method for manufacturing the h-GI-POF high temperature optical fiber.

The inner core layer 10a is formed by integrally forming 5 core layers with the refractive index gradually decreasing from the core to the outside, and comprises a first core layer 11, a second core layer 12, a third core layer 13, a fourth core layer 14 and a fifth core layer 15, wherein the refractive index of the inner core layer 10a gradually decreases from the core to the outside; the outer skin layer 10b is composed of a single skin layer, and the refractive index of the outer skin layer 10b is smaller than that of any one of the core layers of the inner core layer 10 a.

The first core layer 11, the second core layer 12, the third core layer 13, the fourth core layer 14, the fifth core layer 15 and the outer skin layer 10b have a gradient refractive index of 1.3370-1.3560, the edge of the first core layer 11 and the edge of the second core layer 12 form a first blending region, the edge of the second core layer 12 and the edge of the third core layer 13 form a second blending region, the edge of the third core layer 13 and the edge of the fourth core layer 14 form a third blending region, the edge of the fourth core layer 14 and the edge of the fifth core layer 15 form a fourth blending region, and the edge of the fifth core layer and the edge of the outer skin layer 10b form a fifth blending region, so that the first core layer 11, the second core layer 12, the third core layer 13, the fourth core layer 14, the fifth core layer 15 and the outer skin layer 10b form an h-GI-POF high-temperature optical fiber with the refractive index gradually reduced from the core to the outside.

In the present embodiment, the refractive index of the first core layer 11 is 1.3635, the refractive index of the second core layer 12 is 1.3605, the refractive index of the third core layer 13 is 1.3574, the refractive index of the fourth core layer 14 is 1.3543, the refractive index of the fifth core layer 15 is 1.3512, and the refractive index of the outer skin layer 10b is 1.3473; and the diameter of the inner core layer composed of the first core layer 11, the second core layer 12, the third core layer 13, the fourth core layer 14 and the fifth core layer 15 is 50-120 μm. The diameter of the outer skin layer 10b is 490-750 μm.

Example one

Synthesis of high Polymer X1, as shown in FIG. 3

The high polymer X1 was synthesized according to a radical polymerization route, and radicals were supplied from perfluorodibenzoyl peroxide PFDBPO through thermal decomposition.

S101: to the reactor was added n moles of monomer M8A: perfluoro-2-methyl-4, 5-methoether-1, 3-dioxolane, M moles of monomer M8E: perfluoro-3-methylene-2, 4-dioxine bicyclo [4,3,0] nonane, an initiator, wherein n: m =35-90: 10-65; the initiator comprises perfluorodibenzoyl peroxide, and the mass percent of the initiator is 0.05-0.15%;

namely, 244.8 g (0.90 mol) of M8A monomer and 35.6 g (0.10 mol) of M8E monomer were added to a small reactor with good airtightness, followed by 0.280 g (0.1%, w/w) of an initiator;

s102: stirring and introducing nitrogen for cleaning, reducing the pressure of the reaction kettle to 0.35-0.95 atmospheric pressure after cleaning is finished, and heating to 60-90 ℃ for polymerization reaction, wherein the reaction time is 20-40 h;

in the embodiment, the reaction pressure of the reaction kettle is 0.5 atmosphere, the reaction temperature is 80 +/-1 ℃, and the reaction time is 30 hours;

s103: after the reaction is finished, dissolving the reactant by using a solvent hexafluorobenzene, then precipitating by using a solvent chloroform, and repeatedly dissolving and precipitating to obtain a high polymer X; drying the obtained high polymer X in a reduced-pressure oven with the pressure of 0.35-0.95 atmosphere and the temperature of 90-105 ℃ for 20-30 h;

after 30h of reaction, the reactant is heated and dissolved by using enough solvent hexafluorobenzene, so that the solution is colorless and transparent, and then chloroform is used for precipitation; repeating the dissolving and precipitating operations at least three times, thereby obtaining a high polymer X1; then the high polymer X1 is put into a decompression oven with the pressure of 0.5 atmospheric pressure and the temperature of 100 +/-1 ℃ for drying for 24 h. The conversion rate of the high polymer X1 is calculated to be 75%, and the thermal decomposition temperature Td of the high polymer X1 in the air is more than or equal to 300 ℃ measured by a thermogravimetric analysis method TGA, which shows that the high polymer X1 has high thermal stability;

example two

Synthesis of high Polymer X2, as shown in FIG. 3

The high polymer X2 was synthesized according to a radical polymerization route, and radicals were supplied from perfluorodibenzoyl peroxide PFDBPO through thermal decomposition.

The difference between this embodiment and the first embodiment is: the molar masses of M8A monomer and M8E monomer, in this example, 217.6 g (0.8 mol) of M8A monomer, 71.2 g (0.2 mol) of M8E monomer and 0.290 g of initiator, obtain high polymer X2 after polymerization, calculate the conversion rate of the high polymer X2 to be 77%, and determine the thermal decomposition temperature Td of the high polymer X2 in air to be more than or equal to 300 ℃ by using a thermogravimetric analysis method TGA, which indicates that the thermal stability of the high polymer X2 is high.

EXAMPLE III

Synthesis of high Polymer X3, as shown in FIG. 3

The high polymer X3 was synthesized according to a radical polymerization route, and radicals were supplied from perfluorodibenzoyl peroxide PFDBPO through thermal decomposition.

The difference between this embodiment and the first embodiment is: the molar masses of the M8A monomer and the M8E monomer, in this example, 190.4 g (0.7 mol) of the M8A monomer, 106.8 g (0.3 mol) of the M8E monomer and 0.297g of the initiator, after polymerization, high polymer X3 is obtained, the conversion rate of the high polymer X3 is calculated to be 78%, and the thermal decomposition temperature Td of the high polymer X3 in air is determined to be more than or equal to 300 ℃ by using a thermogravimetric analysis method TGA, which indicates that the thermal stability of the high polymer X3 is high.

Example four

Synthesis of high Polymer X4, as shown in FIG. 3

The high polymer X4 was synthesized according to a radical polymerization route, and radicals were supplied from perfluorodibenzoyl peroxide PFDBPO through thermal decomposition.

The difference between this embodiment and the first embodiment is: the molar masses of the M8A monomer and the M8E monomer, in this example, 163.2 g (0.6 mol) of the M8A monomer, 77.6 g (0.4 mol) of the M8E monomer and 0.306g of the initiator, obtained after polymerization, were high polymer X4, the conversion of the high polymer X4 was calculated to be 72%, and the thermal decomposition temperature Td of the high polymer X4 in air, which is measured by thermogravimetric analysis TGA, was not less than 300 ℃, indicating that the thermal stability of the high polymer X4 was high.

EXAMPLE five

Synthesis of high Polymer X5, as shown in FIG. 3

The high polymer X5 was synthesized according to a radical polymerization route, and radicals were supplied from perfluorodibenzoyl peroxide PFDBPO through thermal decomposition.

The difference between this embodiment and the first embodiment is: the molar masses of the M8A monomer and the M8E monomer, in this example, 136.0 g (0.5 mol) of the M8A monomer, 178.0 g (0.5 mol) of the M8E monomer and 0.314g of the initiator, obtain the high polymer X5 after the polymerization reaction, calculate the conversion rate of the high polymer X5 to be 76%, and determine the thermal decomposition temperature Td of the high polymer X5 in the air to be more than or equal to 300 ℃ by using a thermogravimetric analysis method TGA, which indicates that the thermal stability of the high polymer X5 is high.

EXAMPLE six

Synthesis of high Polymer X6, as shown in FIG. 3

The high polymer X6 was synthesized according to a radical polymerization route, and radicals were supplied from perfluorodibenzoyl peroxide PFDBPO through thermal decomposition.

The difference between this embodiment and the first embodiment is: the molar ratio of M8A monomer to M8E monomer, in this example, 95.2 g (0.35 mol) of M8A monomer, 124.6 g (0.65 mol) of M8E monomer and 0.220g of initiator, after polymerization reaction, high polymer X6 is obtained, the conversion rate of the high polymer X6 is calculated to be 80%, and the thermal decomposition temperature Td of the high polymer X6 in air is determined to be more than or equal to 300 ℃ by using a thermogravimetric analysis method TGA, which indicates that the thermal stability of the high polymer X6 is high.

EXAMPLE seven

Physical Properties testing of high Polymer X

Respectively blending the high polymer X1, the high polymer X2, the high polymer X3, the high polymer X4, the high polymer X5 and the high polymer X6 prepared in the first to sixth examples with a penetrating agent in a mixer to obtain six high polymers Y1, Y2, Y3, Y4, Y5 and Y6 with different refractive indexes;

the sequence of blending in the mixer was: firstly, mixing and melting a high polymer X at the temperature of 230-270 ℃; after melting, reducing the temperature by 5-10 ℃, adding a penetrant 1, 3-dibromo tetrafluorobenzene while the mixer rotor operates, mixing for 5-10min, and extruding each high polymer Y; the penetrating agent 1, 3-dibromo tetrafluorobenzene accounts for 0-5% by mass;

i.e., high polymers X1-X6 were separately mixed with small molecule penetrants in a specially designed small Brabender-type mixer. All the movable parts in the mixing chamber are made of special ceramics through casting, so that the fine powder generated by friction of the metal movable parts is reduced, and the pollution is reduced. DBTFB (1, 3-dibromotetrafluorobenzene) was injected into the mixing chamber by a specially prepared syringe. The temperature in the mixing chamber is controlled at 230 ℃ and 270 ℃.

The mixing components are added in the order of adding the high polymer X1-X6 into the mixer, heating and mixing to melt, then lowering the temperature by a little 5-10 deg.C, and adding DBTFB slowly while the mixer rotor is running. After mixing for 5-10 minutes, the mixture sample was extruded, snap cooled and stored at room temperature for future use. The results of physical property tests on the high polymers Y1-Y6 obtained after mixing are shown in Table 1-1, and it can be seen from the tables that the high polymers Y1-Y5 in examples one to six can be used as the core layer of the optical fiber and the high polymer Y6 as the sheath layer. Note: the refractive index performance test of the sample needs to be carried out within one day after the blending test.

TABLE 1-1

	Y1	Y2	Y3	Y4	Y5	Y6
							n:m	90:10	80:20	70:30	60:40	50:50	35:65
Addition amount of micromolecule DBTFB,%/w	5	4	3	2	1	0
							Refractive index of 632nm	1.3635	1.3605	1.3574	1.3543	1.3512	1.3473
The glass transition temperature of the glass is higher than the melting point of the glass,^oC	160	161	165	165	165	165
							light transmittance%	> 98	>98	>98	>98	>98	>98
Degree of crystallization%	0	0	0	0	0	0
							Melting Point	Is free of	Is free of	Is free of	Is free of	Is free of	Is free of

As shown in FIG. 4, the high polymer Y1-Y6 obtained after mixing was subjected to differential scanning calorimetry DSC test, and the DSC curve thereof shows that the high polymer Y1-Y6 has only glass transition temperature Tg and no crystallinity.

Example eight

As shown in fig. 5, a method for preparing an h-GI-POF high temperature optical fiber comprises the following steps:

respectively blending the high polymer X1, the high polymer X2, the high polymer X3, the high polymer X4, the high polymer X5 and the high polymer X6 prepared in the first to sixth examples with a penetrating agent in a mixer to obtain six high polymers Y1, Y2, Y3, Y4, Y5 and Y6 with different refractive indexes, and then injecting the six high polymers with different refractive indexes on a coextrusion system to prepare the h-GI-POF high-temperature optical fiber;

the co-extrusion system comprises a co-extrusion die 100 and six extrusion heads, wherein a first runner 101, a second runner 102, a third runner 103, a fourth runner 104, a fifth runner 105 and a sixth runner 106 are concentrically distributed from the center of the co-extrusion die outwards in sequence, a heating gradual change area is arranged on the co-extrusion die, and the extrusion heads are correspondingly butted with the runners one by one; injecting molten fluids of six high polymers into the first flow channel 101, the second flow channel 102, the third flow channel 103, the fourth flow channel 104, the fifth flow channel 105 and the sixth flow channel 106 in a one-to-one correspondence manner according to the refractive indexes of the six high polymers from large to small through the extrusion head so as to respectively generate a first core layer, a second core layer, a third core layer, a fourth core layer, a fifth core layer and an outer skin layer; and the first core layer, the second core layer, the third core layer, the fourth core layer, the fifth core layer and the outer skin layer are subjected to permeation and diffusion through the heating gradual change region to gradually form the h-GI-POF high-temperature optical fiber.

When the h-GI-POF high-temperature optical fiber is manufactured, six high polymers Y1-Y6 are injected into each extrusion head in a one-to-one correspondence mode according to the refractive indexes of the high polymers from large to small through the extrusion head, namely the material of the extrusion head 1 consists of the formula of the high polymer Y1; the material of extrusion head 2 is composed of a formulation of high polymer Y2; the material of the extrusion head 3 is composed of a formulation of high polymer Y3; the material of the extrusion head 4 consists of a formulation of high polymer Y4; the material of extrusion head 5 is composed of a formulation of high polymer Y5; the material of the extrusion head 6 is composed of a formula of high polymer Y6, each extrusion head supplies a melt of each layer of material to each co-extrusion runner, the melt forms an optical fiber with a concentric circle structure with six layers of initial sections through a die assembly 100, namely, a first core layer 11, a second core layer 12, a third core layer 13, a fourth core layer 14, a fifth core layer 15 and an outer skin layer 10b of the core layers are formed, and the optical fiber structure with the concentric circle structure is shown in fig. 2.

Then, after the concentric circle structure passes through the heating gradient region 107, due to the action of heat, the 1, 3-dibromotetrafluorobenzene of the first core layer 11, the second core layer 12, the third core layer 13, the fourth core layer 14 and the fifth core layer 15 will perform infiltration activity, and the main direction is that the 1, 3-dibromotetrafluorobenzene infiltrates and diffuses to a region with low concentration to form a high polymer optical fiber core layer 10 a. The final diffusion graded optical fiber 108 structure is shown in FIG. 1; the first, second, third, fourth and fifth core layers 11, 12, 13, 14 and 15 are made of 1, 3-dibromotetrafluorobenzene which diffuses mutually to form a cross-sectional optical fiber with a stepwise but overall gradually changing refractive index. The optical fiber is extruded and molded from the co-extrusion die 100, and the diameter and other parameters of the optical fiber are detected by the laser detector 108. Finally, the optical fiber is wound by a take-up roll 109 and a take-up roll 110. As the optical fiber exits the take-up roll 110, the temperature of the fiber has been reduced significantly, well below the glass transition temperature of the high polymer, at which time the relative mobility of the high polymer and the infiltrant is greatly reduced, thereby achieving "pinning" of the infiltrant within the copolymer of the layer to form the combined core layer.

The h-GI-POF high-temperature optical fiber with practicability is prepared by the preparation method of the h-GI-POF high-temperature optical fiber, and the performance of each h-GI-POF high-temperature optical fiber is measured by using a 1310nm laser source, and the data is shown in tables 1-2;

tables 1 to 2

As can be seen from tables 1-2, the optical loss, bandwidth, numerical aperture and bending loss of the prepared h-GI-POF high-temperature optical fiber all meet the requirements of the h-GI-POF high-temperature optical fiber for ultrahigh-speed communication; the optical fiber prepared by the preparation method of the h-GI-POF high-temperature optical fiber can ensure that the produced h-GI-POF high-temperature optical fiber is all suitable for modern ultrahigh-speed communication under the condition of improving the production speed of the h-GI-POF high-temperature optical fiber.

The above description is only a preferred embodiment of the present invention, but the design concept of the present invention is not limited thereto, and any insubstantial modifications made by using the design concept should fall within the scope of infringing on the protection scope of the present invention.

Claims

1. A preparation method of h-GI-POF high-temperature optical fiber is characterized by comprising the following steps:

s1: preparing six high polymers with different refractive indexes;

2. The method of manufacturing a h-GI-POF high temperature optical fiber according to claim 1, wherein: in the step S101, the initiator comprises perfluorodibenzoyl peroxide, and the mass percent of the initiator is 0.05-0.15%.

3. The method of manufacturing a h-GI-POF high temperature optical fiber according to claim 1, wherein: the reaction pressure of the reaction kettle in the step S102 is 0.35-0.95 atmosphere, the reaction temperature is 60-90 ℃, and the reaction time is 20-40 h.

4. The method of manufacturing a h-GI-POF high temperature optical fiber according to claim 1, wherein: and after the step S103, putting the obtained high polymer X into a decompression oven with the pressure of 0.35-0.95 atmospheric pressure and the temperature of 90-105 ℃ for drying for 20-30 h.

5. The method of manufacturing a h-GI-POF high temperature optical fiber according to claim 1, wherein: the blending sequence of the step S104 in the mixer is as follows: firstly, mixing and melting a high polymer X at the temperature of 230-270 ℃; after melting, the temperature is reduced by 5-10 ℃, the penetrant is added while the mixer rotor runs, and then the high polymer of each core layer is extruded after mixing for 5-10 min.

6. The method of manufacturing a h-GI-POF high temperature optical fiber according to claim 5, wherein: the penetrating agent comprises 1, 3-dibromo tetrafluorobenzene, and the mass percent of the 1, 3-dibromo tetrafluorobenzene is 0-5%.

7. An h-GI-POF high temperature optical fiber, which is characterized in that: the h-GI-POF high-temperature optical fiber comprises an inner core layer and an outer skin layer, wherein the inner core layer and the outer skin layer are arranged in a concentric structure, the refractive index of the inner core layer is larger than that of the outer skin layer, the inner core layer and the outer skin layer are composed of high polymers with different refractive indexes, and the high polymers are formed by copolymerizing perfluorodioxolane and perfluorodioxin bicyclononane, and the h-GI-POF high-temperature optical fiber is prepared by applying the preparation method of the h-GI-POF high-temperature optical fiber according to any one of claims 1.

8. The h-GI-POF high temperature optical fiber according to claim 7, wherein: the inner core layer is formed by integrally forming 5 core layers with the refractive index gradually reduced from the core to the outside, and comprises a first core layer, a second core layer, a third core layer, a fourth core layer and a fifth core layer, wherein the fifth core layer, the fourth core layer, the third core layer, the second core layer and the first core layer have the gradient refractive index of 1.3512-1.3635.

9. The h-GI-POF high temperature optical fiber according to claim 8, wherein: the outer skin layer consists of a single skin layer, the outer skin layer having a refractive index of 1.3473.

10. The h-GI-POF high temperature optical fiber according to claim 7, wherein: the optical loss of the h-GI-POF high-temperature optical fiber is 19-31dB/km, and the bandwidth is not less than 760 MHz-km.