CN106811815A - A kind of porous polyolefin fiber containing micro-nano hole and its preparation method and application - Google Patents

Abstract

The present invention provides a kind of porous polyolefin fiber containing micro-nano hole and its preparation method and application, the micro-nano hole that the fiber contains is cylinder, at 10-5000 nanometers, preferably 50-3000 nanometers, the hole in fiber connects or does not connect the average pore size of the micro-nano hole.The raw material sources of the preparation method enrich, simple and effective, low cost, superior performance, with practicality well, while also allowing for industrialized production.The prepared porous polyolefin fiber containing micro-nano hole has pore size adjustable, and even aperture distribution, porosity is high, the features such as steady quality.In insulation, sound-absorbing damping, the field such as water process has broad application prospects the fiber.

Description

A kind of porous polyolefin fiber containing micro-nano holes and its preparation method and application

technical field

The invention relates to a porous fiber, in particular to a porous polyolefin fiber containing micro-nano holes and a preparation method and application thereof.

Background technique

Polyolefin has excellent performance and low price. It is widely used in daily life, industry, agriculture and other fields. It is the largest synthetic resin variety in the world. In recent years, the preparation technology of porous polyolefin fibers containing micro-nanopores has been developed rapidly, and a variety of molding processes and methods that can produce micro-holes in the polymer matrix have been developed, such as phase separation, stretching, core, etc. Tracking method, sintering method, thermal decomposition method, suspension polymerization method, macromolecular structure template method, colloidal crystal template method, micro-foaming technology, etc. The materials prepared by these methods are widely used in many fields due to their large specific surface area and porous structure. The field has very important application value, including insulation materials, packaging materials, adsorption materials, controlled release materials, water treatment, battery separators, human bone marrow substitute materials, chromatographic column materials, etc., and has become an important class of functional polymers. Material.

With the continuation of the development of science and technology, higher technical requirements have been put forward for porous polyolefin fibers containing micro-nanopores, such as the functionalization of micro-nanopore fibers, environmental friendliness, and controllability of microscopic pore structures. For these requirements, more versatile and variable preparation methods must be studied, and more types of new porous polyolefin fibers must be developed.

At present, the methods that can prepare porous polyolefin materials containing micro-nanopores include free radical polymerization, phase separation, stretching, and micro-foaming. Among them, free radical polymerization methods such as suspension polymerization methods generally only obtain granular products, that is, so-called porous microspheres, and it is difficult to obtain integral continuous bulk or long-fiber porous polymer materials; phase separation methods, stretching methods, etc. The existing polymers are made into porous films or porous fibers by physical means, which has high requirements on equipment; and although porous materials can be obtained by using micro-foaming technology, it needs to rely on special physical processes (such as supercritical carbon dioxide gas chemical process), and at the same time it is difficult to obtain porous fibers containing micro-nano pores, and the technical application area is also narrow. Generally speaking, there is a lack of a simple and flexible method to prepare porous polyolefin fibers containing micro-nanopores in this field, and the structure of porous polyolefin fibers containing micro-nanopores obtained by existing methods also needs to be improved.

Contents of the invention

The purpose of the present invention is to overcome the existing technical difficulties, innovatively design the porous polyolefin fiber structure containing micro-nano holes, and provide a high-quality porous polyolefin fiber containing micro-nano holes, the porous fiber has a uniform pore size distribution , Uniform pore size, high porosity and so on. At the same time, it also provides a simple and feasible method for preparing the porous fiber, which has low requirements on equipment and is very beneficial to industrial production.

To achieve the above object, the present invention provides the following technical solutions:

A porous polyolefin fiber containing micro-nano holes, wherein the micro-nano holes are cylindrical, and the average diameter of the micro-nano holes is 10-5000 nanometers.

According to the present invention, the average pore diameter of the micro-nanopores is preferably 50-3000 nanometers, and may also be 100-2000 nanometers.

According to the present invention, the pores in the porous polyolefin fibers are connected or not connected.

According to the present invention, the porosity of the porous polyolefin fibers is between 0.1-50%, preferably 5-45%, more preferably 20-45%.

According to the present invention, the length of the micro/nano pores is 1-5000 times, more preferably 10-1000 times, the average pore diameter of the pores.

According to the present invention, the polyolefins include α-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 4-methyl-1-pentene and some cyclic A class of thermoplastic polymers obtained by the polymerization or copolymerization of olefins such as cyclohexene alone. Preferred are polyethylene (such as low-density polyethylene (LDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), etc.), polypropylene (PP), polybutene (PB), and their copolymers Such as ethylene-propylene copolymer (ie ethylene-propylene copolymer), ethylene-propylene-butylene copolymer (ie ethylene-propylene-butene copolymer), ethylene-butylene copolymer (ie ethylene-butylene copolymer), propylene-butylene copolymer (ie propylene-butene copolymer), etc. More preferably polypropylene (PP), ethylene-propylene copolymer (i.e. ethylene-propylene copolymer), ethylene-propylene-butylene copolymer (i.e. ethylene-propylene-butene copolymer) or propylene-butylene copolymer (i.e. propylene-butene copolymer) .

The present invention further provides the following technical solutions:

A kind of preparation method of above-mentioned porous polyolefin fiber containing micro-nano hole, it comprises the following steps:

(1) Raw materials are prepared, including polyolefin and polyvinyl acetal; each raw material is blended in proportion, spun through melt extrusion, and the prepared fiber is stretched at a certain temperature, and then shaped and rolled to obtain blend fibers;

(2) The blend fiber obtained in step (1) is treated in a suitable solvent and at a suitable temperature to dissolve the polyvinyl acetal in the fiber to form the porous polyolefin fiber containing micro-nano holes .

The present invention also provides the following technical solutions:

A kind of preparation method of above-mentioned porous polyolefin fiber containing micro-nano hole, it comprises the following steps:

(1) Raw materials are prepared, including polyolefin and polyvinyl acetal; each raw material is blended in proportion, melt-blown and spun, and the blend fiber is collected;

(2) The blend fiber obtained in step (1) is treated in a suitable solvent and at a suitable temperature to dissolve the polyvinyl acetal in the fiber to form the porous polyolefin fiber containing micro-nano holes .

According to the present invention, in step (1), blending each raw material in proportion specifically is: melt blending each raw material in a screw extruder in proportion.

According to the present invention, the blending ratio of polyolefin and polyvinyl acetal is 50:50 to 99.9:0.1, preferably 50:50 to 90:10, most preferably 60:40 to 80:20. The ratios are all mass ratios.

According to the present invention, the polyolefins include alpha-olefins such as ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 4-methyl-1-pentene and some A class of thermoplastic polymers obtained by polymerizing or copolymerizing cyclic olefins such as cyclohexene alone. Mainly polyethylene (such as low-density polyethylene (LDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), etc.), polypropylene (PP), polybutene (PB), and their copolymers Such as ethylene-propylene copolymer (ie ethylene-propylene copolymer), ethylene-propylene-butylene copolymer (ie ethylene-propylene-butene copolymer), ethylene-butylene copolymer (ie ethylene-butylene copolymer), propylene-butylene copolymer (ie propylene-butene copolymer), etc. More preferably polypropylene (PP), ethylene-propylene copolymer (i.e. ethylene-propylene copolymer), ethylene-propylene-butylene copolymer (i.e. ethylene-propylene-butene copolymer) or propylene-butylene copolymer (i.e. propylene-butene copolymer) .

According to the present invention, the polyvinyl acetal is the condensation product of polyvinyl alcohol and aldehyde. Preferably, the polyvinyl acetal is selected from polyvinyl formal (PVFO), polyvinyl acetal, polyvinyl propyral, polyvinyl butyral (PVB) and copolymers thereof such as polyvinyl acetal One or more of vinyl formal, polyvinyl ethylpropyral, polyvinyl formal, polyvinyl ethyl butyral, polyvinyl butyral, etc. Preferably, the polyvinyl acetal may be in the form of powder or small solid particles. Preferably, the acetal group content in the polyvinyl acetal ranges from 10% to 80%, preferably 40% to 80%. Preferably, the polyvinyl acetal has a number average molecular weight of 5,000-500,000, preferably 10,000-200,000.

The present invention further provides the following technical solutions:

The above-mentioned porous polyolefin fibers containing micro-nano holes are used as raw materials for heat-retaining, sound-absorbing and filter devices, or as carrier materials for preparing functional and intelligent materials.

Compared with prior art, the present invention produces following beneficial effect:

1. The porous polyolefin fiber containing micro-nano holes of the present invention has high porosity, small pore size, uniform pore size distribution and size, low heat shrinkage, high solvent resistance, and stable quality.

2. The preparation method of the porous polyolefin fiber containing micro-nano holes of the present invention is simple in process, and the obtained product has uniform pore diameter and stable quality.

Description of drawings

The scanning electron micrograph (morphology at 20000 times) of the cross-sectional structure of the porous polyolefin fiber containing micro-nanopores formed in Fig. 1 embodiment 1

The scanning electron micrograph (morphology at 250 times) of the cross-sectional structure of the porous polyolefin fiber containing micro-nanopores formed in Fig. 2 embodiment 1

Scanning electron micrograph of the cross-sectional structure of the porous polyolefin fiber containing micro-nanopores formed in Example 1 of Fig. 3 (the fiber diameter is 60 μm, and the magnification is 10000)

The scanning electron micrograph (fiber diameter is 500 μ m, magnification is 1000) of the cross-sectional structure of the porous polyolefin fiber containing micro-nano hole formed in Fig. 4 embodiment 1

The scanning electron micrograph (fiber diameter is 800 μ m, magnification is 500) of the cross-sectional structure of the porous polyolefin fiber containing micro-nano hole formed in Fig. 5 embodiment 1

detailed description

The technical problem to be solved by the present invention is to provide a method for preparing porous polyolefin fibers containing micro-nano pores for the deficiencies in the existing background technology. The porous polyolefin fibers obtained by the method have high porosity, relatively Small pore size (micro-nano pore size) and uniform pore size distribution and size, with certain mechanical strength, low density and high specific surface area, thus low thermal shrinkage and high solvent resistance, and stable quality. In the method, as long as the composition and ratio of the blend are adjusted and the spinning rate is changed, the required porous polyolefin fiber containing micro-nano holes can be prepared. This method has great advantages, and it is flexible and changeable. , simple and easy to operate, and the prepared polyolefin fiber has the characteristics of micro-nano pore size.

In a preferred embodiment of the present invention, the described porous polyolefin fiber containing micro-nano holes is prepared by the following steps:

(1) Raw materials are prepared, including polyolefin and polyvinyl acetal; each raw material is blended in proportion, spun through melt extrusion, and the prepared fiber is stretched at a certain temperature, and then shaped and rolled to obtain blend fibers;

(2) The blend fiber obtained in step (1) is treated in a suitable solvent and at a suitable temperature to dissolve the polyvinyl acetal in the fiber to form the porous polyolefin fiber containing micro-nano holes .

Specifically, in step (1), each raw material is added into the screw extruder in proportion, and after being fully melted and blended in the screw extruder, it is passed through the spinning assembly and sprayed from a spinneret with an aperture of 0.1 to 2 mm. The jetted melt stream is cooled by air blowing to obtain primary fibers. Among them, the temperature of each zone of the screw is: feed section 70-210°C, compression section 90-230°C and metering section 90-230°C; spinning assembly temperature 90-230°C, spinneret temperature 90-250°C, primary silk spinning The speed is 10-200m/min. The above-mentioned as-spun fibers are stretched in 1-3 stages in a hot air oven at a temperature of 80-180° C., and heat-set and wound at a temperature of 60-120° C. to obtain the blend fiber. The blend fiber has a diameter in the range of 1-1000 μm, preferably 200-900 μm, more preferably 60-800 μm. Specifically, in the method of the present invention, the distribution of pore size and porosity can be controlled by changing the spinning rate and controlling the diameter of the spinning.

In a preferred embodiment of the present invention, the described porous polyolefin fiber containing micro-nano holes is prepared by the following steps:

(1) Raw materials are prepared, including polyolefin and polyvinyl acetal; each raw material is blended in proportion, melt-blown and spun, and the blend fiber is collected;

(2) The blend fiber obtained in step (1) is treated in a suitable solvent and at a suitable temperature to dissolve the polyvinyl acetal in the fiber to form the porous polyolefin fiber containing micro-nano holes .

Specifically, in step (1), each raw material is added to the screw extruder in proportion, and after being fully melted and blended in the screw extruder, it passes through the spinneret assembly and is sprayed from a spinneret with an aperture of 0.1 to 2mm Out, the blend fibers are formed after cooling on a receiving wire. Among them, the temperature of each zone of the screw is: feed section 70-210°C, compression section 90-230°C and metering section 90-230°C, spinneret temperature 200-250°C (preferably 230°C), spinneret temperature 90-250°C °C (preferably 190 °C). The blend fiber has a diameter in the range of 0.1-100 μm, preferably 1-50 μm. Specifically, in the method of the present invention, the distribution of pore size and porosity can be controlled by changing the spinning rate and controlling the diameter of the spinning.

In a preferred embodiment of the present invention, the polyvinyl acetal in the blend fiber obtained in the dissolution step (1) in the above step (2) is to treat the blend fiber in a solvent to dissolve polyvinyl acetal.

Wherein, the selected solvent is a solvent that can dissolve the polyvinyl acetal polymer but not the polyolefin used at a certain temperature, and can be a pure solvent or a mixture of several solvents. Preferably, the solvent includes alcohol solvents, such as methanol, ethanol, n-propanol, isopropanol, butanol, n-pentanol, hexanol, heptanol, n-octanol, isooctyl alcohol, benzyl alcohol, diacetone Alcohol, etc.; ether solvents, such as ethylene glycol ether, propylene glycol ether, methyl ether, propyl ether, etc.; ketone solvents, such as acetone, methyl ethyl ketone, cyclohexanone, diisobutyl ketone, isophorone, methyl pyrrolidone etc.; acid solvents, such as acetic acid, etc.; ester solvents, such as methyl acetate, ethyl acetate, butyl acetate, isopropyl acetate, etc.; amide solvents, such as N,N-dimethylacetamide (DMF) , N,N-dimethylformamide, etc.; hydrocarbon solvents, such as dichloromethane, dichloroethane, chloroform, dichloropropane, toluene, etc., can dissolve polyvinyl acetal but do not dissolve the polyolefin used, Mixed solvents of the above solvents can also be selected in order to obtain better results, such as a mixed solution of toluene and absolute ethanol, a mixed solution of xylene and n-butanol, a mixed solution of ethanol and propanol, a mixed solution of propanol and acetone, And the mixed solution of butanol, toluene and ethyl acetate, etc. The treatment temperature range is 0-130°C, preferably 25-100°C. The treatment time is 12-48h, preferably 12-24h.

Specifically, the pore size of the micro-nanopores is affected by the polyvinyl acetal content, processing temperature and/or spinning speed. By controlling the above parameters and optimizing the appropriate process parameters, the prepared porous polyolefin fiber containing micro-nano pores has the characteristics of adjustable pore size, uniform pore size distribution, high porosity, and stable quality.

Compared with existing porous polyolefin fibers and preparation technology thereof, the present invention has the advantages of:

(1) The preparation method provided by the present invention has a simple preparation process, strong versatility, and a wide range of applicable polymer materials. The method mainly uses polyolefin and polyvinyl acetal as blending components, does not change the chemical structure and performance of the polyolefin, is easy to operate, and is beneficial to industrial production.

(2) The porous polyolefin fiber containing micro-nano holes of the present invention has uniform pore size distribution, adjustable pore size and good repeatability. The preparation of the porous polyolefin fiber containing micro-nanopores of the present invention does not need to be polymerized, and the industrially known melt blending method is adopted, and the phase separation generated during the processing is controllable, so that the prepared polyolefin fiber containing The porous polyolefin fiber with micro-nano holes has a continuous structure, and the pore size is easy to control.

(3) The polyolefin fiber containing micro-nano holes of the present invention can be used as a carrier material for preparing functionalized and intelligent materials. It is widely used in the separation, filtration, adsorption and integration of instrument analysis, water treatment, thermal insulation materials, battery diaphragm, biomedicine and other industries. Such as microfiltration and intelligent insulation materials, heavy metal removal, chromatographic monolithic column stationary phase, enzyme immobilization, cell culture, drug sustained release, chemical sensors, etc.

The present invention will be described in further detail below through specific implementation examples in order to clarify the technical solutions to be protected by the present invention. It should be noted that these embodiments are preferred examples of the present invention for those skilled in the art to understand the present invention, but the present invention is not limited to these embodiments.

The materials used in the following examples, unless otherwise specified, are commercially available or known products in the prior art.

Example 1

Add 30 parts of polyvinyl butyral (PVB) powder and 70 parts of PP pellets into the screw extruder, and after fully melt-blending in the screw extruder, pass through the spinning assembly and start from a hole diameter of 0.1 to The 2mm spinneret is sprayed out, and the sprayed melt stream is cooled by blowing to obtain primary fibers; wherein, the temperature of each zone of the screw is: 70-210°C in the feed section, 90-230°C in the compression section and 90-230°C in the metering section. °C, the temperature of the spinning assembly is 90-230 °C, the temperature of the spinneret is 90-250 °C, and the spinning speed of the as-spun silk is 10-200 m/min. The above-mentioned as-spun fibers are stretched in 1-3 stages in a hot air oven at a temperature of 80-180° C., and heat-set and wound at a temperature of 60-120° C. to obtain the blend fiber. Wherein, by changing the drawing rate during spinning (that is, the spinning speed of as-spun filaments), a series of blend fibers with different diameters (fiber diameters between 60-800 μm) are obtained.

The resulting blend fibers with different diameters were placed in a container filled with absolute ethanol solvent, and the fibers were boiled at 80°C for 12h. The fiber after removing PVB is fully dried to obtain the porous polyolefin fiber containing micro-nano holes of the present invention. For porous polyolefin fibers with different fiber diameters, a small amount was taken, brittlely broken with liquid nitrogen, and then sprayed with gold on the surface, and the cross-sectional morphology was observed in a scanning electron microscope. Figures 1-5 are scanning electron micrographs of different magnifications at different fiber diameters.

Porosity is defined as pore volume/bulk material volume, which is converted in this paper by blend mass:

Porosity = (mass of polyvinyl acetal/density of polyvinyl acetal)/(mass of polyolefin/density of polyolefin)

The resulting porous fiber has a uniform pore size distribution and a high porosity. The relevant parameters are shown in the following table:

Example 2

The difference from Example 1 is that 20 parts of polyvinyl butyral (PVB) powder and 80 parts of PP pellets are melt-blended, the solvent selected to remove PVB is isopropanol, and the fiber is heated at a temperature of 90 ° C. Boil down 24h, all the other are identical with embodiment 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 3

The difference from Example 2 is that 15 parts of polyvinyl butyral (PVB) powder and 85 parts of HDPE pellets are melt-blended, and the rest are the same as in Example 2.

The pore diameter, pore spacing and porosity of the obtained porous polyolefin fibers are similar to those of Example 2.

Example 4

The difference from Example 2 is that 20 parts of polyvinyl formal (PVFO) powder and 80 parts of PP pellets are melt-blended, the solvent selected to remove PVFO is n-butanol, and the rest are the same as in Example 2 .

The pore diameter, pore spacing and porosity of the obtained porous polyolefin fibers are similar to those of Example 2.

Example 5

The difference from Example 2 is that 5 parts of polyvinyl butyral (PVB) powder is melt-blended with 95 parts of PP pellets, and the rest are the same as in Example 2.

The pore diameter, pore spacing and porosity of the obtained porous polyolefin fibers are similar to those of Example 2.

Example 6

The difference from Example 1 is that the solvent selected to remove PVB is isooctyl alcohol, the fiber is boiled at 80° C. for 24 hours, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 7

The difference from Example 1 is that the solvent selected to remove PVB is a mixed solution of toluene and absolute ethanol, the weight ratio of toluene to absolute ethanol is 3:2, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 8

The difference from Example 1 is that the solvent selected to remove PVB is a mixed solution of xylene and n-butanol, the weight ratio of xylene to n-butanol is 3:2, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 9

The difference from Example 1 is that 30 parts of polyvinyl butyral (PVB) powder and 70 parts of ethylene-propylene-butylene terpolymer pellets are melt-blended, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 10

The difference from Example 1 is that 30 parts of polyvinyl formal powder and 70 parts of PP pellets are melt-blended, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 11

The difference from Example 1 is that the selected solvent for removing PVB is ethyl acetate with a mass fraction of 85%, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 12

The difference from Example 1 is that the solvent selected to remove PVB is ethylene glycol butyl ether, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 13

The difference from Example 1 is that the solvent selected to remove PVB is cyclohexanone, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 14

The difference from Example 1 is that the solvent selected to remove PVB is diacetone alcohol, and all the other are the same as Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 15

The difference with Example 1 is that the solvent selected to remove PVB is anhydrous acetic acid, and all the other are the same as Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 16

The difference from Example 1 is that the solvent selected to remove PVB is N,N-dimethylformamide, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 17

The difference from Example 1 is that the solvent selected to remove PVB is dimethyl sulfoxide, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 18

The difference from Example 1 is that the solvent selected to remove PVB is methanol, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 19

The difference from Example 1 is that the solvent selected to remove PVB is methylene chloride, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 20

The difference from Example 1 is that the solvent selected to remove PVB is methylpyrrolidone, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 21

The difference from Example 1 is that the solvent selected to remove PVB is tetrahydrofuran (THF), and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 22

The difference from Example 1 is that 30 parts of polyvinyl butyral (PVB) powder and 70 parts of PB pellets are melt-blended, and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 23

The difference from Example 1 is that the solvent selected to remove PVB is N,N-dimethylacetamide (DMF), and the rest are the same as in Example 1.

The pore size, pore distance and porosity of the obtained porous polyolefin fibers are similar to those of Example 1.

Example 24

Put 30 parts of polyvinyl butyral (PVB) powder and 70 parts of PP pellets into the screw extruder, and after fully melted and blended in the screw extruder, pass through the spinneret assembly and start from a hole diameter of 0.1 to Spray from a spinneret of 2 mm, and obtain a series of fibers with different diameters (fiber diameters between 1 and 50 μm) after cooling on the receiving net. Among them, the temperature of each zone of the screw is: 70-210°C in the feed section, 90-230°C in the compression section and 90-230°C in the metering section; the temperature of the spinneret assembly is 230°C, and the temperature of the spinneret plate is 190°C.

The obtained fibers with different diameters were placed in a container filled with absolute ethanol solvent, and the fibers were boiled at 80° C. for 12 hours. The fiber after removing PVB is fully dried to obtain the porous polyolefin fiber containing micro-nano holes of the present invention. The scanning electron micrograph of the fiber is similar to Example 1.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this field Those skilled in the art, without departing from the scope of the technical solution of the present invention, can use the method and technical content disclosed above to make some changes or modifications to equivalent embodiments with equivalent changes, but all those that do not depart from the technical solution of the present invention Content, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims (10)

1. a kind of porous polyolefin fiber containing micro-nano hole, wherein, the micro-nano hole is cylinder, The average pore size of the micro-nano hole is at 10-5000 nanometers.

The average pore size of the micro-nano hole is preferably 50-3000 nanometers, can also be 100-2000 nanometers.

Preferably, the hole in the porous polyolefin fiber connects or does not connect.

Preferably, the porosity of the porous polyolefin fiber is between 0.1-50%, more preferably 5-45%, Even more preferably from 20-45%.

Preferably, the length of the micro-nano hole is 1-5000 times of the average pore size in hole, more preferably 10-1000 Times.

Preferably, described polyolefin include ethene, propylene, 1- butylene, 1- amylenes, 1- hexenes, 1- octenes, The alpha-olefins such as 4-methyl-1-pentene and some cycloolefins such as cyclohexene etc. be polymerized alone or combined polymerization and obtain An analog thermoplastic polymer.It is preferred that having polyethylene (such as low density polyethylene (LDPE) (LDPE), high-density polyethylene Alkene (HDPE), linear low density polyethylene (LLDPE) (LLDPE) etc.), polypropylene (PP), polybutene (PB), And its copolymer such as ethylene-propylene copolymer (i.e. ethylene-propylene copolymer), the third fourth of second copolymer (i.e. ethylene-propylene - butylene copolymer), second fourth copolymer (i.e. ethylene-butene copolymer), the third fourth copolymer (i.e. propylene-fourth Alkene copolymer) etc..More preferably polypropylene (PP), ethylene-propylene copolymer (i.e. ethylene-propylene copolymer), The third fourth of second copolymer (i.e. ene-propylene-butene copolymer) or the third fourth copolymer (i.e. propene-1-butene copolymer).

2. the preparation method of the porous polyolefin fiber containing micro-nano hole described in claim 1, it includes Following steps：

(1) raw material, including polyolefin and polyvinyl acetal are prepared；Each raw material is carried out in proportion Blending, spinning is carried out by melting extrusion, and the fiber of preparation is stretched, then shaped at a certain temperature Winding, obtains blend fibers；

(2) blend fibers obtained by step (1) are processed in suitable solvent and at suitable temperature, Polyvinyl acetal in fiber described in dissolution, forms the described porous polyolefin fiber containing micro-nano hole.

3. the preparation method of the porous polyolefin fiber containing micro-nano hole described in claim 1, it includes Following steps：

(1) raw material, including polyolefin and polyvinyl acetal are prepared；Each raw material is carried out in proportion Blending, by melt-spraying spinning, and collection obtains blend fibers；

(2) blend fibers obtained by step (1) are processed in suitable solvent and at suitable temperature, Polyvinyl acetal in fiber described in dissolution, forms the described porous polyolefin fiber containing micro-nano hole.

4. it is according to the method in claim 2 or 3, it is characterised in that in step (1), that each is former Material is blended specifically in proportion：Each raw material is carried out in screw extruder in proportion to melt altogether It is mixed.

5. the method according to claim 2 or 4, it is characterised in that in step (1), each is former Material is proportionally added into screw extruder, after carrying out abundant melt blending in screw extruder, by spinning Component and from aperture be 0.1~2mm spinneret in spray, the melt stream of ejection is obtained just through quenching Raw fiber；By above-mentioned as-spun fibre through the hot-air oven that temperature is 80~180 DEG C, 1~3 grade of stretching is carried out, Thermal finalization winding is carried out at being 60~120 DEG C in temperature, described blend fibers are obtained.

Preferably, the diameter range of the blend fibers be 1-1000 μm, more preferably 200-900 μm, Still more preferably 60-800 μm.

Preferably, each area's temperature of screw rod is：70~210 DEG C of feed zone, 90~230 DEG C of compression section and metering 90~230 DEG C of section；90~230 DEG C of filament spinning component temperature, 90~250 DEG C of spinneret temperature, silk spinning of coming into being Speed is 10~200m/min.

Preferably, described polyolefin include ethene, propylene, 1- butylene, 1- amylenes, 1- hexenes, 1- octenes, The alpha-olefins such as 4-methyl-1-pentene and some cycloolefins such as cyclohexene etc. be polymerized alone or combined polymerization and obtain An analog thermoplastic polymer.It is preferred that having polyethylene (such as low density polyethylene (LDPE) (LDPE), high-density polyethylene Alkene (HDPE), linear low density polyethylene (LLDPE) (LLDPE) etc.), polypropylene (PP), polybutene (PB), And its copolymer such as ethylene-propylene copolymer (i.e. ethylene-propylene copolymer), the third fourth of second copolymer (i.e. ethylene-propylene - butylene copolymer), second fourth copolymer (i.e. ethylene-butene copolymer), the third fourth copolymer (i.e. propylene-fourth Alkene copolymer) etc..More preferably polypropylene (PP), ethylene-propylene copolymer (i.e. ethylene-propylene copolymer), The third fourth of second copolymer (i.e. ene-propylene-butene copolymer) or the third fourth copolymer (i.e. propene-1-butene copolymer).

6. the method according to claim 3 or 4, it is characterised in that in step (1), each is former Material is proportionally added into screw extruder, after carrying out abundant melt blending in screw extruder, by spinneret Component and from aperture be 0.1~2mm spinneret in spray, form described blending after online cooling is received Fibres.

Preferably, the diameter range of the blend fibers is 0.1-100 μm, preferably 1-50 μm.

Preferably, each area's temperature of screw rod is：70~210 DEG C of feed zone, 90~230 DEG C of compression section and metering 90~230 DEG C of section；200~250 DEG C of spinning pack temperature (preferably 230 DEG C), spinneret temperature 90~250 DEG C (preferably 190 DEG C).

Described polyolefin includes ethene, propylene, 1- butylene, 1- amylenes, 1- hexenes, 1- octenes, 4- methyl The alpha-olefins such as -1- amylenes and some cycloolefins as cyclohexene etc. be polymerized alone or combined polymerization obtained from a class Thermoplastic polymer.It is preferred that have polyethylene (such as low density polyethylene (LDPE) (LDPE), high density polyethylene (HDPE) (HDPE), Linear low density polyethylene (LLDPE) (LLDPE) etc.), polypropylene (PP), polybutene (PB), and its altogether Polymers such as ethylene-propylene copolymer (i.e. ethylene-propylene copolymer), the third fourth of second copolymer (i.e. ene-propylene-butene Copolymer), second fourth copolymer (i.e. ethylene-butene copolymer), the third fourth copolymer (i.e. propene-1-butene copolymerization Thing) etc..More preferably polyethylene (such as low density polyethylene (LDPE) (LDPE), high density polyethylene (HDPE) (HDPE), Linear low density polyethylene (LLDPE) (LLDPE) etc.) or polypropylene (PP).

7. the method according to claim any one of 2-6, it is characterised in that polyolefin and polyvinyl The blending ratio of acetal is 50:50 to 99.9:0.1, wherein preferably 50:50 to 90:10, most preferably 60:40 To 80:20.The ratio is mass ratio.

8. the method according to claim any one of 2-7, it is characterised in that described polyvinyl contracting Aldehyde, is the condensation product of polyethylene alcohols and aldehydes.Preferably, the polyvinyl acetal contracts selected from polyvinyl alcohol Formaldehyde (PVFO), polyvinyl acetal, polyvinyl alcohol contracting propionic aldehyde, polyvinyl butyral resin (PVB) And its copolymer such as polyvinyl formal acetal, polyvinyl alcohol contracting second propionic aldehyde, polyvinyl alcohol contracting first butyraldehyde, gather One or more in vinyl alcohol contracting second butyraldehyde, polyvinyl alcohol third butyraldehyde of contracting etc..Preferably, the polyethylene Base acetal can be powder or solid granule shape.Preferably, the acetal radical content in the polyvinyl acetal Scope is 10%-80%, preferably 40%-80%.Preferably, the equal molecule of the number of the polyvinyl acetal Amount selection is 5,000-500,000, preferably 10,000-200,000.

9. the method according to claim any one of 2-8, it is characterised in that institute in above-mentioned steps (2) The suitable solvent stated is that can dissolve polyvinyl acetal polymer but insoluble polyene used at a certain temperature The solvent of hydrocarbon, can be the mixture of a kind of neat solvent, or several solvents.Preferably, it is described molten Agent includes alcohols solvent, such as methyl alcohol, ethanol, normal propyl alcohol, isopropanol, butanol, n-amyl alcohol, hexanol, heptan Alcohol, n-octyl alcohol, isooctanol, phenmethylol, diacetone alcohol etc.；Ether solvent, such as ethylene glycol ethyl ether, the third two Alcohol ether, methyl ether, propyl ether etc.；Ketones solvent, such as acetone, MEK, cyclohexanone, DIBK, Isophorone, methyl pyrrolidone etc.；Acids solvent, such as acetic acid；Esters solvent, such as methyl acetate, Ethyl acetate, butyl acetate, isopropyl acetate etc.；Amide solvent, such as DMA (DMF), N,N-dimethylformamide etc.；Varsol, such as dichloromethane, dichloroethanes, chloroform, dichloropropane, The solvent of the dissolvable polyvinyl acetal such as toluene but insoluble polyolefin used, also may be selected above-mentioned solvent The mixed solution of the mixed solution of mixed solvent, such as toluene and absolute ethyl alcohol, dimethylbenzene and n-butanol, ethanol With the mixed solution of propyl alcohol, the mixing of the mixed solution of propyl alcohol and acetone, and butanol and toluene and ethyl acetate Solution.

Preferably, the temperature ranges in the step (2) are 0-130 DEG C, preferably 25-100 DEG C； Process time is 12-48h, preferably 12-24h.

10. described in claim 1 or claim any one of 2-9 described in containing of preparing of method The application of the porous polyolefin fiber of micro-nano hole, its as warming, sound-absorbing, the raw material of filter element, Or as preparation functionalization, the carrier material of smart material.