CN109234850B

CN109234850B - Cross-linked modified ultra-high molecular weight polyethylene fiber and preparation method thereof

Info

Publication number: CN109234850B
Application number: CN201810883121.3A
Authority: CN
Inventors: 王依民; 倪建华; 王燕萍; 夏于旻; 何勇; 朱卫彪
Original assignee: Donghua University
Current assignee: JIANGSU SHENHE TECHNOLOGY DEVELOPMENT Co.,Ltd.
Priority date: 2018-08-06
Filing date: 2018-08-06
Publication date: 2020-01-17
Anticipated expiration: 2038-08-06
Also published as: CN109234850A

Abstract

The invention relates to a cross-linked modified ultrahigh molecular weight polyethylene fiber and a preparation method thereof, wherein VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor is subjected to multi-stage hot drawing treatment, and cross-linking is initiated during the final stage of hot drawing treatment to prepare the cross-linked modified ultrahigh molecular weight polyethylene fiber. The prepared cross-linked modified ultra-high molecular weight polyethylene fiber has the creep elongation of 5.04-5.85% under the conditions that the temperature is 70 ℃, the load is 300MPa and the initial stage load time is 10 days, the equilibrium stage load time is 130 days, and the creep elongation is 0.56-0.62%; under the conditions that the load is 15MPa and the heating rate is 2 ℃/min, the fracture temperature is 196-206 ℃. The method has simple process, and the prepared fiber has good mechanical property, creep resistance and heat resistance and has extremely good popularization value.

Description

Cross-linked modified ultra-high molecular weight polyethylene fiber and preparation method thereof

Technical Field

The invention belongs to the field of fiber modification, relates to a modified ultrahigh molecular weight polyethylene fiber, and particularly relates to a cross-linked modified ultrahigh molecular weight polyethylene fiber and a preparation method thereof.

Background

Due to excellent mechanical properties, chemical resistance, impact resistance, bending resistance, low temperature resistance and weather resistance, ultra-high molecular weight polyethylene (UHMWPE) fibers and fiber composites thereof are gaining wide attention in the fields of aerospace, individual protection, ocean engineering, new energy, sports equipment and the like. But due to the fact that UHMWPE has large molecular weight and high chain entanglement of the molecular structure, the UHMWPE has large viscosity and is difficult to process, and the concentration of the spinning solution is generally 5-16 wt% in the conventional industrialized gel spinning or dry spinning method; in addition, due to the fact that polar acting force does not exist among UHMWPE molecules, the UHMWPE fibers are poor in heat resistance and easy to creep, and in the actual use process, products are easy to reduce in strength and increase in elongation, so that the application of the UHMWPE fibers in various fields is limited. In order to improve creep resistance and heat resistance of UHMWPE, UHWMPE needs to be crosslinked. The nature of the crosslinking treatment is that free radicals are generated on molecular chains of the UHMWPE, and polymerization reaction occurs between the free radicals. After crosslinking, a three-dimensional structure is formed between the molecular chains, the slippage between the molecular chains is difficult, and the creep resistance of the UHWMPE product is effectively improved.

Patent CN103993479 discloses a method for preparing silane cross-linked modified ultra-high molecular weight polyethylene (UHMWPE) fibers by placing undried UHMWPE gel fibers in a modifying solution for ultrasonic extraction treatment and then performing multistage thermal stretching. Although the method gradually initiates grafting and crosslinking in the multistage drawing process, the mechanical property of the fiber is not influenced, the process is simple, the amount of a coupling agent and an initiator entering the fiber is difficult to control during ultrasonic extraction, crosslinking is performed at the early stage of hot drawing, the fiber drawing rate is increased, the crystallinity and the orientation degree of the fiber are influenced to a certain degree, and the strength is damaged. Patent CN201110434278 mentions a method of firstly soaking UHWMPE fiber in n-heptane, namely, firstly swelling the fiber, then washing and drying, then soaking in a crosslinking solution, and finally improving the performance of the UHWMPE fiber through radiation crosslinking and thermal crosslinking. Although the method improves the crosslinking point and improves the creep resistance of the UHMWPE fiber, the process is more complex, and simultaneously, because of the compact structure of the fiber, the crosslinking agent only stays on the surface of the fiber and is difficult to enter the fiber, and the organic solvent adopted in the treatment process is difficult to treat. Patent CN1431358 proposes a method for improving the heat resistance, creep resistance and adhesion of UHMWPE fibers by first soaking the fibers in an organic solvent of a photosensitizer and an acrylate crosslinking agent and then crosslinking by ultraviolet, which method has the problems of long treatment time on one hand, difficult access of the crosslinking agent to the interior of the fibers by staying only on the surface of the fibers, and difficult treatment of the organic solvent on the other hand. Patent USP4870136 also mentions a method of plasticizing melt spinning using UHMWPE powder, a radical initiator, a silane compound and a diluent, completing silanization grafting in the spinning stage, hot-drawing the fiber in an extractant and a crosslinking agent, and finally crosslinking in boiling water, which improves the creep resistance, heat resistance and surface adhesion of UHMWPE fibers, but the method adds an initiator and a grafting compound in the spinning solution, on the one hand, the presence of the initiator affects the fiber properties, and in addition, drawing is performed after grafting, the drawing ratio is lower, and the mechanical properties of the obtained fiber are also not high. Patent CN103193908 is to prepare heterogeneous catalyst by loading UHMWPE catalyst on nano carrier with single loading site and then on porous carrier, and compared with traditional catalyst, heterogeneous catalyst has the distance between catalysts separated by the physical size of POSS molecule, and forms active sites separated by POSS molecule, and the active sites are far away from each other. During polymerization, the growing polyethylene chain segment is not easy to wind, so that the non-winding ultrahigh molecular weight polyethylene fiber can be efficiently prepared at relatively high temperature, the tensile strength of the fiber is greatly improved, and the processability is improved. However, the method relates to the field of raw material synthesis, the process is complex, and the requirements cannot be met through simple modification of the existing spinning technology. In addition, researchers also study that the creep resistance and the heat resistance of the UHWMPE are improved by adding materials such as carbon nano tubes, graphene and nano silicon dioxide, but the methods can improve the viscosity of the spinning solution and are not beneficial to the normal spinning.

In conclusion, in the prior art, the UHWMPE fiber prepared by the method cannot simultaneously improve the creep resistance and the heat resistance of the UHWMPE fiber on the premise of not improving the viscosity of the spinning solution, and the problems that the organic solvent is difficult to treat or the amount of the coupling agent entering the fiber is difficult to control also exist.

Therefore, the research on a simple and efficient preparation method which can simultaneously improve the creep resistance and the heat resistance of the UHWMPE fiber is of great significance.

Disclosure of Invention

The invention aims to overcome the problems in the prior art and provide a simple and efficient preparation method of cross-linked modified ultrahigh molecular weight polyethylene fiber, which can simultaneously improve the creep resistance and the heat resistance of the fiber.

In order to achieve the purpose, the invention adopts the technical scheme that:

the creep elongation of the cross-linked modified ultra-high molecular weight polyethylene fiber is 5.04-5.85% under the conditions that the temperature is 70 ℃, the load is 300MPa and the initial stage load time is 10 days, the equilibrium stage load time is 130 days, and the creep elongation is 0.56-0.62%; under the conditions that the load is 15MPa and the heating rate is 2 ℃/min, the fracture temperature is 196-206 ℃.

As a preferred technical scheme:

the cross-linked modified ultrahigh molecular weight polyethylene fiber mainly comprises ultrahigh molecular weight polyethylene and VPOSS uniformly dispersed in the ultrahigh molecular weight polyethylene, and cross-linked between molecular chains of the ultrahigh molecular weight polyethylene and between the molecular chains of the ultrahigh molecular weight polyethylene and the VPOSS.

The crosslinked and modified ultrahigh molecular weight polyethylene fiber has a fineness of 1.2 to 2.0dtex, a tensile strength of 23.6 to 29cN/dtex, and a tensile modulus of 720 to 820 cN/dtex.

The invention also provides a method for preparing the crosslinking modified ultrahigh molecular weight polyethylene fiber, which comprises the steps of carrying out multi-stage hot drawing treatment on the VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor, and initiating crosslinking to prepare the crosslinking modified ultrahigh molecular weight polyethylene fiber when carrying out the last stage hot drawing treatment (namely the last stage carried out according to the time sequence). The existing crosslinking mode is to directly perform electron beam irradiation crosslinking or soak the fiber, and the soaking penetrates crosslinkable components into the fiber for crosslinking, so that the crosslinking components are easily distributed unevenly in the direction vertical to the fiber axis, and the fiber performance is unstable, while the heat resistance of the fiber prepared by the method of direct electron beam irradiation crosslinking still needs to be improved. The VPOSS-containing ultrahigh molecular weight polyethylene fiber disclosed by the invention uniformly contains crosslinkable components namely octavinyl POSS (POSS), and after crosslinking, the fiber performance is uniform and stable, and the creep resistance and heat resistance of the fiber can be effectively improved. Meanwhile, crosslinking is initiated at the last stage of hot drawing treatment, so that the crosslinking can be carried out under the condition of ensuring the tension, and the shrinkage of the fiber caused by crosslinking is reduced.

As a preferred technical scheme:

in the method, the multistage hot drawing is three-stage hot drawing, and the specific process parameters are as follows:

the first-stage thermal drafting multiple is 3-5 times; the first-stage thermal drafting temperature is 80-110 ℃;

the second-stage thermal drafting multiple is 1.5-2 times; the second-stage thermal drafting temperature is 95-115 ℃;

the third-stage thermal drafting multiple is 1.1-1.2 times; the temperature of the third-stage hot drawing is 115-135 ℃.

The induced crosslinking is carried out in the third-stage hot drawing process, if the crosslinking is carried out in the first-stage or second-stage hot drawing process, the subsequent fiber is difficult to draw, the drawing multiplying power is low, and the fiber strength is not high. The multi-stage hot drawing of the present invention includes, but is not limited to, three stages, and the hot drawing process is applicable to the present invention as long as it can ensure that the fiber can be sufficiently drawn during the hot drawing process, thereby ensuring the mechanical properties of the finally produced fiber.

In the method, the third stage of thermal drawing is performed in a nitrogen or inert gas atmosphere, so that the inhibition effect of oxygen on the crosslinking reaction can be reduced, the fiber curing speed is high, and the productivity is improved.

The method is characterized in that the induced crosslinking is realized by carrying out electron beam irradiation treatment on the VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor in a third-stage hot drawing process; the electron beam irradiation treatment is carried out, so that cross-linking between VPOSS double bonds and ethylene chains and between ethylene chains can be initiated, meanwhile, the electron beam irradiation treatment is adopted, the cross-linking reaction can be carried out without adding an initiator, and whether the fibers are crystallized has little influence on the effect of the electron beam irradiation treatment;

the electron beam irradiation treatment intensity is 200-300 kGy, the irradiation dose rate is 20-40 kGy/s, the electron beam energy is too high, UHWMPE molecular chains are broken, the fiber strength is influenced, the electron beam energy is too low, double bond activation crosslinking on VPOSS cannot be initiated, and the creep resistance and the heat resistance are not obviously improved.

As described above, the VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor is prepared by extruding and drawing a spinning dope prepared by uniformly mixing a VPOSS solution with solvent I and ultrahigh molecular weight polyethylene powder and then swelling and dissolving. Cage type silsesquioxane (POSS) is a nano-sized organic silicon compound with a special molecular structure, the molecule of the cage type silsesquioxane takes an inorganic silica framework as a core, and the endpoint of a polyhedron is an organic substituent group. When the POSS is blended with a plurality of polymers, the compatibility of molecular level can be achieved, the interaction between molecular chains can be weakened to a certain extent, particularly the interaction between polyethylene branched chains, and a certain lubricating effect and a certain plasticizing effect are achieved; in addition, the inorganic framework of the blend can improve the heat resistance of the blend. When the dosage is proper, the mechanical property of the blend material is not influenced or can be improved to a certain extent. The VPOSS, namely the octavinyl POSS is one of the POSS, and the VPOSS also has eight vinyl groups, so that the VPOSS can be used as a lubricant and a plasticizer, the viscosity of a spinning stock solution is reduced, the concentration of ultra-high molecular weight polyethylene in the spinning stock solution is improved, the production efficiency and the product stability are improved, and the VPOSS can react with active groups on polyethylene chains for crosslinking during electron beam irradiation treatment in a later stage of thermal drafting, thereby playing an anchoring role and improving the heat resistance and the creep resistance of UHMWPE fibers. In addition, VPOSS contained in the fibers has a certain micro-nano structure, so that a certain concave-convex structure can be formed on the surfaces of the fibers, and when the fibers are used for preparing a composite material, the bonding area between the fibers and resin is enlarged, and the bonding force between the fibers and the resin is improved.

According to the method, the solvent II in the VPOSS solution is xylene, and the solvent I and the VPOSS are uniformly mixed, so that the uniformity of the VPOSS in the spinning solution can be promoted, and the agglomeration of POSS is reduced;

the mass ratio of VPOSS to the solvent II is 1: 1; VPOSS in the spinning solution accounts for 3-7% of the weight of the ultra-high molecular weight polyethylene powder; the VPOSS addition amount is too low, the lubricating and plasticizing effects are not obvious, the concentration of the ultra-high molecular weight polyethylene in the spinning solution can be increased to a limited extent, the crosslinking degree is not high during subsequent electron beam irradiation treatment, the creep resistance and the heat resistance of the fiber are increased to a limited extent, the addition amount is too high, so that the UHWMPE molecular chains in the unit cross section are few, the fiber strength is low, the subsequent crosslinking is not sufficient easily, the non-crosslinked VPOSS plays a role in lubricating and plasticizing, but the creep resistance of the fiber is reduced, in addition, the addition amount is too high, the spinning solution swells, the viscosity after dissolution is increased on the contrary, and the concentration of the ultra-high molecular weight polyethylene in the spinning solution is not;

the weight of the ultrahigh molecular weight polyethylene powder is 8-25% of the sum of the weight of the solvent I and the weight of the solvent II; under the same condition, the concentration of the ultra-high molecular weight polyethylene in the spinning solution without VPOSS is 7-20 wt%, when the VPOSS and the UHWMPE are blended, the compatibility of molecular level can be achieved, the interaction among molecular chains is weakened to a certain extent, particularly the interaction among polyethylene branched chains plays a certain role in lubrication and plasticization, and thus the concentration of the ultra-high molecular weight polyethylene in the spinning solution is improved;

the solvent I is decahydronaphthalene and/or xylene.

In the method, the xylene is more than one of paraxylene, metaxylene and orthoxylene.

The invention mechanism is as follows:

the invention relates to a cross-linking modified ultra-high molecular weight polyethylene fiber and a preparation method thereof, which comprises the steps of firstly uniformly mixing a VPOSS solution with a solvent I and ultra-high molecular weight polyethylene powder to obtain a spinning stock solution, then spinning to obtain an ultra-high molecular weight polyethylene fiber precursor containing VPOSS, wherein xylene in the VPOSS solution is uniformly mixed with VPOSS, so that the uniformity of VPOSS in the spinning stock solution can be promoted, the agglomeration of VPOSS is reduced, the VPOSS can play the role of a lubricant and a plasticizer in the spinning stock solution, the viscosity of the spinning stock solution is reduced, the concentration of ultra-high molecular weight polyethylene in the spinning stock solution is increased, then the ultra-high molecular weight polyethylene fiber precursor containing VPOSS is subjected to multi-stage hot drawing treatment and is subjected to cross-linking during the last stage hot drawing treatment to obtain the cross-linking modified ultra-high molecular weight polyethylene fiber, in the process, the ultra-high molecular weight polyethylene fiber precursor is fully drawn, the mechanical property of the fiber is ensured, the crosslinking is initiated by electron beam irradiation, free radicals are generated on a UHWMPE molecular chain under the electron beam irradiation, meanwhile, as the VPOSS has eight vinyl groups, the reactive groups are more, the vinyl double bond of the VPOSS is broken to generate a plurality of free radicals, the free radicals can be rapidly compounded into bonds, namely, the VPOSS double bond and the vinyl chain as well as the vinyl chain and the chain are fully crosslinked to generate a three-dimensional reticular crosslinking structure, and the creep resistance and the heat resistance of the prepared fiber are improved.

Has the advantages that:

(1) the preparation method of the cross-linked modified ultra-high molecular weight polyethylene fiber has simple process, does not need to change the existing drafting equipment, only needs to add electron beam radiation equipment in the third-stage hot drafting process, and is convenient and easy to implement;

(2) according to the preparation method of the cross-linked modified ultra-high molecular weight polyethylene fiber, after VPOSS is added, the viscosity of the spinning solution is reduced, the concentration of the ultra-high molecular weight polyethylene in the spinning solution can be increased, and the production efficiency and the product stability are improved;

(3) according to the preparation method of the cross-linked modified ultra-high molecular weight polyethylene fiber, VPOSS cross-linkable double bonds are more, the activity is high, and the creep resistance and the heat resistance of the fiber can be improved conveniently through electron beam cross-linking and curing;

(4) according to the preparation method of the cross-linked modified ultra-high molecular weight polyethylene fiber, cross-linking can be initiated between the VPOSS double bond and the ethylene chain and between the ethylene chains by electron beam irradiation treatment, and the operation is simple;

(5) according to the preparation method of the cross-linked modified ultra-high molecular weight polyethylene fiber, cross-linking is initiated during the final-stage hot drawing treatment, so that the fiber can be fully drawn, the shrinkage of the fiber caused by cross-linking is reduced, and the mechanical property of the fiber is ensured;

(6) the cross-linked modified ultra-high molecular weight polyethylene fiber has good mechanical property, creep resistance and heat resistance.

Detailed Description

The invention will be further illustrated with reference to specific embodiments. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

Example 1

The preparation method of the cross-linked modified ultra-high molecular weight polyethylene fiber comprises the following specific steps:

(1) carrying out ultrasonic treatment on p-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing the VPOSS solution with decalin and ultra-high molecular weight polyethylene powder with the viscosity average molecular weight of 100 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with the length-diameter ratio of 48, and dissolving the mixture at the temperature of 160 ℃ to obtain a spinning stock solution, wherein the VPOSS accounts for 3% of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder accounts for 11% of the sum of the mass of the p-xylene and;

(2) extruding the spinning solution by a metering pump, a spinning manifold and a spinneret plate, heating to remove the solvent and simultaneously drafting to prepare the VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor, wherein the drafting ratio is 10, and the pressure of the spinning manifold is 28 MPa;

(3) carrying out three-stage hot drawing treatment on the VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor, and initiating crosslinking to prepare the crosslinked modified ultrahigh molecular weight polyethylene fiber during the last-stage hot drawing treatment, wherein the specific process parameters are as follows:

the first-stage thermal stretching multiple is 4 times; the first-stage hot drawing temperature is 80 ℃;

the second-stage thermal stretching multiple is 2 times; the second-stage hot drawing temperature is 95 ℃;

the third-stage hot stretching multiple is 1.2 times; the third stage hot draw temperature was 115 ℃.

And performing electron beam irradiation treatment on the ultra-high molecular weight polyethylene fiber precursor containing the VPOSS in the third-stage hot drawing process to realize crosslinking among ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 200kGy, and the irradiation dose rate is 20 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.63 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.62 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 196 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 1.5dtex, the tensile strength is 24cN/dtex, and the tensile modulus is 730 cN/dtex.

Comparative example 1

The process for producing an ultrahigh molecular weight polyethylene fiber was substantially the same as in example 1, except that the intensity of the third-stage hot-drawn electron beam irradiation treatment in step (3) was 400 kGy. The prepared ultra-high molecular weight polyethylene fiber has reduced tensile property and creep resistance, the tensile strength is 12cN/dtex, the tensile modulus is 450cN/dtex, under the conditions that the temperature is 70 ℃, the load is 300MPa and the initial stage load time is 10 days, the creep elongation is 5.40 percent, the equilibrium stage load time is 130 days, and the creep elongation is 0.57 percent; the fracture temperature is 198 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min.

Comparing comparative example 1 with example 1, it is found that the creep resistance and heat resistance of the fiber are not changed significantly, but the tensile strength and tensile modulus of the fiber are greatly reduced, which is caused by the molecular chain breaking and decomposing and the molecular chain shortening due to the over-high electron beam irradiation strength. The electron beam irradiation intensity of the fiber is 200-300 kGy, the crosslinking among the ultrahigh molecular weight polyethylene molecular chains, the crosslinking between the ultrahigh molecular weight polyethylene molecular chains and the VPOSS and the inorganic structure of the VPOSS effectively improve the creep resistance and the tensile property of the fiber.

Comparative example 2

The process for producing an ultrahigh-molecular-weight polyethylene fiber was substantially the same as in example 1, except that the intensity of the third-stage hot-drawn electron beam irradiation treatment in step (3) was 100 kGy. The prepared ultra-high molecular weight polyethylene fiber has reduced tensile property and creep resistance, the tensile strength is 14cN/dtex, the tensile modulus is 680cN/dtex, under the conditions that the temperature is 70 ℃, the load is 300MPa and the initial stage load time is 10 days, the creep elongation is 7.63 percent, the equilibrium stage load time is 130 days, and the creep elongation is 1.55 percent; the fracture temperature is 168 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min.

Comparing comparative example 2 with example 1, it was found that the tensile strength, tensile modulus, creep resistance and heat resistance of the fiber were all reduced to some extent due to insufficient electron beam irradiation strength, insufficient VPOSS reaction, and "lubrication" and "plasticization" effects of VPOSS not participating in the crosslinking reaction. Therefore, the electron beam irradiation intensity is 200-300 kGy, the crosslinking among the ultrahigh molecular weight polyethylene molecular chains, the crosslinking between the ultrahigh molecular weight polyethylene molecular chains and the VPOSS and the inorganic structure of the VPOSS effectively improve the creep resistance and the tensile property of the fiber.

Example 2

(1) carrying out ultrasonic treatment on m-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing the VPOSS solution with decalin and ultra-high molecular weight polyethylene powder with the viscosity average molecular weight of 150 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with the length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain spinning stock solution, wherein the VPOSS accounts for 6% of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder accounts for 8% of the sum of the masses of the m-xylene and the decalin;

the first-stage thermal stretching multiple is 4 times; the first-stage hot drawing temperature is 110 ℃;

the second-stage thermal drawing multiple is 1.8 times; the second stage hot drawing temperature is 115 ℃;

the third-stage hot stretching multiple is 1.1 times; the third stage hot draw temperature is 135 ℃.

And performing electron beam irradiation treatment on the ultra-high molecular weight polyethylene fiber precursor containing the VPOSS in the third-stage hot drawing process to realize crosslinking among ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 300kGy, and the irradiation dose rate is 24 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.04 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.56 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; under the conditions of 15MPa of load and 2 ℃/min of heating rate, the fracture temperature is 206 ℃. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 1.2dtex, the tensile strength is 23.6cN/dtex, and the tensile modulus is 820 cN/dtex.

Comparative example 3

The preparation method of the ultra-high molecular weight polyethylene fiber is basically consistent with the embodiment 2, except that VPOSS is not contained in the spinning solution in the step (1), in the process of preparing the precursor fiber in the step (2), the nascent fiber is broken and continuous under the pressure of 28MPa of a spinning box, normal spinning can be carried out after pressurization to 36MPa, the tensile modulus and the creep resistance of the finally prepared ultra-high molecular weight polyethylene fiber are reduced, the tensile strength is 16.8cN/dtex, the tensile modulus is 600cN/dtex, the creep elongation is 7.02 percent under the conditions that the temperature is 70 ℃, the load is 300MPa, and the loading time in the initial stage is 10 days, the loading time in the balance stage is 130 days, and the creep elongation is 1.04 percent; the fracture temperature is 138 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min.

When comparative example 3 is compared with example 2, under the same conditions, the spinning beam pressure at normal continuous spinning is reduced from 36MPa to 28MPa after example 2 is added with VPOSS, because the molecular nanometer size of VPOSS reduces the interaction among molecular chains to a certain extent, particularly the interaction among polyethylene branched chains, and plays a certain role in lubrication and plasticization. In addition, after VPOSS is added, electron beam irradiation treatment is carried out in the third stage of hot drawing process, crosslinking is carried out between the VPOSS and polyethylene chains and among polyethylene molecular chains, and the creep resistance and the heat resistance of the fiber are obviously improved by the aid of the inorganic structure of the VPOSS.

Comparative example 4

The preparation method of the ultra-high molecular weight polyethylene fiber is basically consistent with the embodiment 2, except that the VPOSS content in the spinning solution in the step (1) is 10% of the weight of the ultra-high molecular weight polyethylene powder, other steps are consistent, the tensile modulus and the creep resistance of the finally prepared ultra-high molecular weight polyethylene fiber are reduced, the tensile strength is 13cN/dtex, the tensile modulus is 700cN/dtex, the creep elongation is 6.15% under the conditions that the temperature is 70 ℃, the load is 300MPa and the initial stage load time is 10 days, the equilibrium stage load time is 130 days, and the creep elongation is 0.86%; the fracture temperature is 200 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min.

Comparing comparative example 4 with example 2, it is found that the tensile strength, tensile modulus and creep resistance of the fiber are all reduced slightly under the same conditions, because the excessive addition of VPOSS results in less VPOSS molecular chains in unit cross-sectional area, low fiber strength and easy insufficient subsequent crosslinking, and the un-crosslinked VPOSS plays a role in lubrication and plasticization, but reduces the creep resistance and heat resistance of the fiber.

Example 3

(1) carrying out ultrasonic treatment on o-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing the VPOSS solution with decalin and ultrahigh molecular weight polyethylene powder with the viscosity average molecular weight of 200 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with the length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain a spinning stock solution, wherein the VPOSS accounts for 6% of the weight of the ultrahigh molecular weight polyethylene powder, and the ultrahigh molecular weight polyethylene powder accounts for 15% of the sum of the masses of the o-xylene and the decalin;

the first-stage thermal stretching multiple is 5 times; the first-stage hot drawing temperature is 90 ℃;

the second-stage thermal drawing multiple is 1.8 times; the second-stage hot drawing temperature is 110 ℃;

the third-stage hot stretching multiple is 1.2 times; the third stage hot draw temperature was 125 ℃.

And performing electron beam irradiation treatment on the ultra-high molecular weight polyethylene fiber precursor containing the VPOSS in the third-stage hot drawing process to realize crosslinking among ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 250kGy, and the irradiation dose rate is 28 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.85 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.60 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 200 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 1.6dtex, the tensile strength is 27cN/dtex, and the tensile modulus is 770 cN/dtex.

Comparative example 5

The preparation method of the ultra-high molecular weight polyethylene fiber is basically consistent with the embodiment 3, except that the first-stage drawing temperature in the step (3) is 90 ℃; performing electron beam irradiation on the first-stage drawing under the protection of nitrogen, wherein the intensity of electron beam irradiation treatment is 250kGy, the fiber is broken when the drawing multiple is 5 times, and the fiber can be normally drawn when the drawing multiple is 3.2 times; the second-stage stretching temperature is 110 ℃, when the second-stage stretching multiple is 1.8 times, the fiber is broken, and the fiber can be normally stretched when the second-stage stretching multiple is 1.5 times; the third stage drawing temperature is 125 ℃, the fiber has broken yarn phenomenon when the third stage drawing multiple is 1.2 times, 1.1 times can be normally drawn, and the third stage hot drawing is carried out in nitrogen atmosphere. Other steps are consistent, the tensile modulus and the creep resistance of the finally prepared ultra-high molecular weight polyethylene fiber are reduced, the tensile strength is 13cN/dtex, the tensile modulus is 630cN/dtex, under the conditions that the temperature is 70 ℃, the load is 300MPa and the initial stage load time is 10 days, the creep elongation is 6.18 percent, the equilibrium stage load time is 130 days, and the creep elongation is 0.65 percent; the fracture temperature is 198 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min.

Comparing comparative example 5 with example 3, it is found that the fiber of this example has significantly reduced stretching ratio, tensile strength and tensile modulus, because this example is irradiated for crosslinking in the first-stage stretching process, resulting in three-dimensional crosslinked structure inside the fiber, after the three-dimensional crosslinked structure is formed, the molecular chains are difficult to be fully oriented, the stretching ratio is limited, and the fiber tensile strength and tensile modulus are reduced.

Example 4

(1) carrying out ultrasonic treatment on p-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing the VPOSS solution with decalin and ultra-high molecular weight polyethylene powder with the viscosity average molecular weight of 150 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with the length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain spinning stock solution, wherein the VPOSS accounts for 3% of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder accounts for 22% of the sum of the masses of the p-xylene and the decalin;

(2) extruding and stretching the spinning solution under the conditions of a drafting ratio of 10 and a spinning box pressure of 28MPa to prepare VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor;

the first-stage thermal stretching multiple is 3.5 times; the first-stage hot drawing temperature is 110 ℃;

the second-stage thermal drafting multiple is 1.5 times; the second stage hot drawing temperature is 115 ℃;

the third-stage hot stretching multiple is 1.1 times; the third stage hot draw temperature is 130 ℃.

And performing electron beam irradiation treatment on the ultra-high molecular weight polyethylene fiber precursor containing the VPOSS in the third-stage hot drawing process to realize crosslinking among ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 280kGy, and the irradiation dose rate is 33 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.82 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.58 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 202 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 1.8dtex, the tensile strength is 29cN/dtex, and the tensile modulus is 720 cN/dtex.

Example 5

(1) carrying out ultrasonic treatment on o-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing the VPOSS solution with p-xylene and ultra-high molecular weight polyethylene powder with the viscosity average molecular weight of 150 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with the length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain a spinning stock solution, wherein the VPOSS accounts for 4% of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder accounts for 19% of the sum of the masses of the o-xylene;

the first-stage thermal stretching multiple is 3 times; the first-stage hot drawing temperature is 95 ℃;

the second-stage thermal drafting multiple is 1.6 times; the second-stage hot drawing temperature is 105 ℃;

the third-stage hot stretching multiple is 1.15 times; the third stage hot drawing temperature is 120 ℃.

And performing electron beam irradiation treatment on the ultrahigh molecular weight polyethylene fiber precursor containing VPOSS in the third-stage hot drawing process to realize crosslinking among ultrahigh molecular weight polyethylene molecular chains and between the ultrahigh molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 240kGy, and the irradiation dose rate is 29 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.25 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.59 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 199 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 1.7dtex, the tensile strength is 28cN/dtex, and the tensile modulus is 780 cN/dtex.

Example 6

(1) carrying out ultrasonic treatment on p-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing the VPOSS solution with m-xylene and ultra-high molecular weight polyethylene powder with the viscosity-average molecular weight of 150 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with the length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain a spinning stock solution, wherein the VPOSS accounts for 7% of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder accounts for 10% of the sum of the mass of the;

the first-stage thermal draft multiple is 3.6 times; the first-stage hot drawing temperature is 102 ℃;

the second-stage thermal drafting multiple is 1.5 times; the second-stage hot drawing temperature is 98 ℃;

the third-stage hot stretching multiple is 1.1 times; the third stage hot draw temperature was 125 ℃.

And performing electron beam irradiation treatment on the ultra-high molecular weight polyethylene fiber precursor containing VPOSS in the third-stage hot drawing process to realize crosslinking among ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 200kGy, and the irradiation dose rate is 25 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.71 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.62 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 205 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 2.0dtex, the tensile strength is 29cN/dtex, and the tensile modulus is 790 cN/dtex.

Example 7

(1) carrying out ultrasonic treatment on m-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing the VPOSS solution with o-xylene and ultra-high molecular weight polyethylene powder with the viscosity average molecular weight of 150 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with the length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain a spinning stock solution, wherein the VPOSS accounts for 5% of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder accounts for 25% of the sum of the masses of the m-xylene;

the first-stage thermal stretching multiple is 5 times; the first-stage hot drawing temperature is 85 ℃;

the second-stage thermal stretching multiple is 1.9 times; the second-stage hot drawing temperature is 110 ℃;

the third-stage hot drawing multiple is 1.18 times; the third stage hot draw temperature is 130 ℃.

And performing electron beam irradiation treatment on the ultrahigh molecular weight polyethylene fiber precursor containing VPOSS in the third-stage hot drawing process to realize crosslinking among ultrahigh molecular weight polyethylene molecular chains and between the ultrahigh molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 260kGy, and the irradiation dose rate is 30 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.75 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.62 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 196 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 2.0dtex, the tensile strength is 26.3cN/dtex, and the tensile modulus is 780 cN/dtex.

Example 8

(1) carrying out ultrasonic treatment on ortho-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing a mixture of para-xylene and meta-xylene (in a mass ratio of 1:1), the VPOSS solution and ultrahigh molecular weight polyethylene powder with a viscosity-average molecular weight of 100 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with a length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain spinning stock solution, wherein the VPS accounts for 3% of the weight of the ultrahigh molecular weight polyethylene powder, and the ultrahigh molecular weight polyethylene powder accounts for 23% of the sum of the masses of the para-xylene, the meta-xylene and;

the first-stage thermal stretching multiple is 3 times; the first-stage hot drawing temperature is 85 ℃;

the second-stage thermal stretching multiple is 2 times; the second-stage hot drawing temperature is 98 ℃;

the third-stage hot stretching multiple is 1.1 times; the third stage hot draw temperature is 122 ℃.

And performing electron beam irradiation treatment on the ultra-high molecular weight polyethylene fiber precursor containing VPOSS in the third-stage hot drawing process to realize crosslinking among ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 200kGy, and the irradiation dose rate is 40 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.04 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.60 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 198 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 1.9dtex, the tensile strength is 25.3cN/dtex, and the tensile modulus is 820 cN/dtex.

Example 9

(1) carrying out ultrasonic treatment on m-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing a mixture of decalin and p-xylene (the mass ratio is 2:1), the VPOSS solution and ultra-high molecular weight polyethylene powder with the viscosity average molecular weight of 100 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using a double screw with the length-diameter ratio of 48, and dissolving the mixture at the temperature of 160 ℃ to obtain a spinning solution, wherein the VPOSS is 6 percent of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder is 8 percent of the sum of the mass of the mixture of the decalin and the;

the third-stage hot stretching multiple is 1.12 times; the third stage hot draw temperature is 135 ℃.

And performing electron beam irradiation treatment on the ultrahigh molecular weight polyethylene fiber precursor containing VPOSS in the third-stage hot drawing process to realize crosslinking among ultrahigh molecular weight polyethylene molecular chains and between the ultrahigh molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 260kGy, and the irradiation dose rate is 25 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.77 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.56 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 201 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 1.3dtex, the tensile strength is 28cN/dtex, and the tensile modulus is 790 cN/dtex.

Example 10

(1) carrying out ultrasonic treatment on m-xylene and VPOSS in a mass ratio of 1:1 for 30 minutes to obtain a VPOSS solution, uniformly mixing a mixture of decalin, p-xylene and o-xylene (the mass ratio is 1:1:2), the VPOSS solution and ultra-high molecular weight polyethylene powder with the viscosity average molecular weight of 100 ten thousand, adding the mixture into a stainless steel reaction kettle, heating the mixture to 60 ℃ under the stirring action, swelling the mixture for 2 hours, extruding the mixture by using double screws with a length-diameter ratio of 48, and dissolving the mixture at 160 ℃ to obtain spinning stock solution, wherein the VPOSS accounts for 7 percent of the weight of the ultra-high molecular weight polyethylene powder, and the ultra-high molecular weight polyethylene powder accounts for 24 percent of the sum of the mass of the decalin, the p-xylene, the o-;

the first-stage thermal stretching multiple is 3.5 times; the first-stage hot drawing temperature is 92 ℃;

the second-stage thermal stretching multiple is 1.7 times; the second stage hot drawing temperature is 115 ℃;

the third-stage hot stretching multiple is 1.1 times; the third stage hot draw temperature was 118 ℃.

And performing electron beam irradiation treatment on the ultra-high molecular weight polyethylene fiber precursor containing VPOSS in the third-stage hot drawing process to realize crosslinking among ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the intensity of the electron beam irradiation treatment is 280kGy, and the irradiation dose rate is 35 kGy/s.

The finally prepared cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and has the creep elongation of 5.85 percent, the load time of 130 days in the equilibrium stage and the creep elongation of 0.61 percent under the conditions that the temperature is 70 ℃, the load is 300MPa and the load time of the initial stage is 10 days; the fracture temperature is 203 ℃ under the conditions that the load is 15MPa and the heating rate is 2 ℃/min. The titer of the crosslinked and modified ultra-high molecular weight polyethylene fiber is 2.0dtex, the tensile strength is 26.5cN/dtex, and the tensile modulus is 810 cN/dtex.

Claims

1. The cross-linked modified ultra-high molecular weight polyethylene fiber is characterized in that: the creep elongation of the cross-linked modified ultra-high molecular weight polyethylene fiber is 5.04-5.85% under the conditions that the temperature is 70 ℃, the load is 300MPa and the initial stage load time is 10 days, the equilibrium stage load time is 130 days, and the creep elongation is 0.56-0.62%; under the conditions that the load is 15MPa and the heating rate is 2 ℃/min, the fracture temperature is 196-206 ℃;

the cross-linked modified ultra-high molecular weight polyethylene fiber mainly comprises ultra-high molecular weight polyethylene and VPOSS uniformly dispersed in the ultra-high molecular weight polyethylene, and cross-linking is carried out between ultra-high molecular weight polyethylene molecular chains and between the ultra-high molecular weight polyethylene molecular chains and the VPOSS, wherein the VPOSS refers to octavinyl POSS.

2. The crosslinked and modified ultra-high molecular weight polyethylene fiber according to claim 1, wherein the crosslinked and modified ultra-high molecular weight polyethylene fiber has a fineness of 1.2 to 2.0dtex, a tensile strength of 23.6 to 29cN/dtex, and a tensile modulus of 720 to 820 cN/dtex.

3. The method for preparing the cross-linked modified ultra-high molecular weight polyethylene fiber according to any one of claims 1 to 2, characterized by comprising: and carrying out multi-stage hot drawing treatment on the VPOSS-containing ultrahigh molecular weight polyethylene fiber precursor, and initiating crosslinking to prepare the crosslinked modified ultrahigh molecular weight polyethylene fiber during the last stage of hot drawing treatment.

4. The method according to claim 3, wherein the multistage hot drawing is three-stage hot drawing, and the specific process parameters are as follows:

5. The process according to claim 4, wherein said third thermal drawing is carried out under nitrogen or an inert gas atmosphere.

6. The method according to claim 5, wherein the induced crosslinking is realized by performing electron beam irradiation treatment on the VPOSS-containing ultra-high molecular weight polyethylene fiber precursor in a third-stage hot drawing process, wherein the intensity of the electron beam irradiation treatment is 200-300 kGy, and the irradiation radiation rate is 20-40 kGy/s.

7. The method of claim 3, wherein the VPOSS-containing ultra-high molecular weight polyethylene fiber precursor is prepared by extruding and drawing a spinning solution, wherein the spinning solution is prepared by uniformly mixing a VPOSS solution with the solvent I and the ultra-high molecular weight polyethylene powder and then swelling and dissolving the mixture.

8. The process according to claim 7, wherein the solvent II in the VPOSS solution is xylene and the mass ratio of VPOSS to solvent II is 1: 1; in the spinning solution, VPOSS accounts for 3-7% of the weight of the ultrahigh molecular weight polyethylene powder, the ultrahigh molecular weight polyethylene powder accounts for 8-25% of the sum of the mass of a solvent I and a solvent II, and the solvent I is decalin and/or xylene.

9. The method of claim 8, wherein the xylene is one or more of paraxylene, metaxylene, and orthoxylene.