阅读说明：本技术 一种光交联纳米纤维原位增韧聚合物材料的制备方法 (Preparation method of photo-crosslinking nanofiber in-situ toughening polymer material ) 是由 朴哲范 贾迎宾 吴昊 赵近川 于 2020-06-08 设计创作，主要内容包括：本发明公开了1)聚合物弹性体混合粒料的制备；2)复合纤维材料的制备；3)交联复合纤维材料的制备；4)光交联纳米纤维原位增韧聚合物材料的制备。本发明通过原位形成聚合物弹性体纳米纤维,增大了聚合物弹性体的比表面积,对原位形成的聚合物弹性体纳米纤维进行光交联,保证其在后续加工中能保持纳米纤维形态,不仅提升了对基体聚合物材料的增韧效果,而且保证了基体聚合物的其他力学性能,可大大减少聚合物弹性体材料用量；选用光源为波长大于350nm的LED紫外光或波长小于500nm的LED蓝光,可减少紫外光对聚合物基体的损伤；聚合物弹性体含量小于3％就可达到良好的增韧效果,低的聚合物弹性体含量不影响聚合物的回收利用。(The invention discloses 1) preparation of polymer elastomer mixed granules; 2) preparing a composite fiber material; 3) preparing a cross-linked composite fiber material; 4) and (3) preparing the photo-crosslinking nano fiber in-situ toughening polymer material. According to the invention, the polymer elastomer nanofiber is formed in situ, so that the specific surface area of the polymer elastomer is increased, the polymer elastomer nanofiber formed in situ is subjected to photo-crosslinking, the nanofiber form can be kept in subsequent processing, the toughening effect on a matrix polymer material is improved, other mechanical properties of the matrix polymer are ensured, and the using amount of the polymer elastomer material can be greatly reduced; the light source is selected to be LED ultraviolet light with the wavelength of more than 350nm or LED blue light with the wavelength of less than 500nm, so that the damage of the ultraviolet light to the polymer matrix can be reduced; good toughening effect can be achieved when the content of the polymer elastomer is less than 3%, and the recycling of the polymer is not influenced by the low content of the polymer elastomer.)

1. A preparation method of a photo-crosslinking nanofiber in-situ toughening polymer material is characterized by comprising the following steps: the method comprises the following steps:

1) preparation of polymer elastomer hybrid pellets: the polymer elastomer mixed granules comprise 0.48-25 wt.% of polymer elastomer, 0.01-2 wt.% of cross-linking agent, 0-2.5 wt.% of photoinitiator and 0.01 wt.% of other auxiliaries, and are added into plastication equipment to be uniformly mixed to obtain a mixture, and then the mixture is added into a granulation extruder to be extruded and granulated;

2) preparing a composite fiber material: sequentially adding the polymer elastomer mixed granules prepared in the step 1), 70.5-99.5 wt.% of matrix polymer and antioxidant into a screw extruder, carrying out melt blending to obtain a blended melt, then passing the blended melt through a spinneret plate, extruding the blended melt through spinneret holes in the spinneret plate to form melt trickle, drafting the melt trickle to form a composite fiber material, and passing the composite fiber material through a collecting device to form a composite fiber net or composite fiber cloth;

3) preparing a cross-linked composite fiber material: irradiating the composite fiber net or the composite fiber cloth prepared in the step 2) with a light source to crosslink the composite fiber net or the composite fiber cloth to obtain a crosslinked composite fiber material, wherein the light source is LED ultraviolet light with the wavelength of more than 350nm or LED blue light with the wavelength of less than 500 nm;

4) preparing a photo-crosslinking nanofiber in-situ toughening polymer material: adding the crosslinked composite fiber material prepared in the step 3) into a granulating extruder for extruding and granulating to obtain the photo-crosslinked nanofiber in-situ toughening polymer material.

2. The method of claim 1, wherein the polymer elastomer is at least one of natural rubber, ethylene propylene rubber, polybutadiene rubber, styrene butadiene rubber, nitrile butadiene rubber, polyolefin block copolymer, polystyrene thermoplastic elastomer, ethylene-vinyl acetate copolymer, polyurethane elastomer, thermoplastic polyester elastomer, thermoplastic polyamide elastomer, polybutylene adipate terephthalate, polycaprolactone, polybutylene succinate, thermoplastic silicone rubber, and fluororubber.

3. The method for preparing the photo-crosslinking nano fiber in-situ toughening polymer material according to claim 1 or 2, wherein the polymer elastomer is in a granular or powder form.

4. The method for preparing the photo-crosslinking nano-fiber in-situ toughening polymer material according to claim 1, wherein the crosslinking agent is one or more of trimethylolpropane tri-propylene ester, trimethylolpropane tri-propylene acrylate, triallyl isocyanurate, triallyl cyanurate, dicumyl peroxide, thiocyanuric acid, trimethoxy silane and gamma- (methacryloyloxy) propyl trimethoxy silane.

5. The method for preparing a photo-crosslinking nano-fiber in-situ toughening polymer material according to claim 1, wherein the photoinitiator is one or more of benzophenone, 1-hydroxycyclohexyl phenyl ketone, 4- (dimethylamino) benzophenone, 4' -bis (N, N-dimethylamino) benzophenone, photoinitiator TPO, benzoin dimethyl ether, tetraethyl mikrolone, isopropyl thioxanthone, 2-chlorothioxanthone, and 9-thioxanthone.

6. The method for preparing the photo-crosslinking nano-fiber in-situ toughening polymer material according to claim 1, wherein the matrix polymer is one or two of polyethylene, polypropylene, polylactic acid, polystyrene, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polymethyl methacrylate, polyamide polymer, ABS plastic, polyvinylidene fluoride and polysulfone.

7. The method for preparing the photo-crosslinking nano-fiber in-situ toughening polymer material according to claim 1, wherein the other auxiliary agent is an auxiliary agent for a composition suitable for polymer processing, and is selected from a flame retardant, an antistatic agent, a lubricant and/or a mildew preventive.

8. The method for preparing the photo-crosslinking nano-fiber in-situ toughening polymer material according to claim 1, wherein the light source is LED ultraviolet light with a wavelength of more than 350nm or LED blue light with a wavelength of less than 500nm, and the wavelength is selected from one or two of 365nm, 385nm, 395nm, 405nm, 420nm and 455 nm.

9. The method for preparing the photo-crosslinking nano fiber in-situ toughening polymer material according to claim 1, wherein the drawing mode is one or two of hot air drawing or cold air drawing.

Technical Field

The invention relates to the technical field of preparation methods of nanofiber toughened polymer materials, in particular to a preparation method of a photocrosslinking nanofiber in-situ toughened polymer material.

Background

In recent years, with the development of economy and market demand, polymer materials such as polyethylene, polypropylene, polylactic acid, polystyrene, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, and the like have been developed very rapidly, and are widely used in the fields of food processing, toys for children, biomedicine, national defense and military industry, municipal engineering, and the like. The polymer material has some defects, and at present, the polymer elastomer is often used for modifying the polymer material. One of the main methods for modifying polymeric materials is to blend polymers and thermoplastic elastomers. The polymer elastomer is present in the polymer matrix as micron-sized spherical particles, and the elastomer addition is generally above 15%. The method can obviously reduce the strength and modulus of the polymer while toughening, and has influence on the optical performance, the processing performance and the like of the polymer matrix.

In addition, ultraviolet light with a wavelength of less than 350nm irradiates the polymer material, which leads to molecular chain breakage of the polymer matrix material, resulting in reduced material performance.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a preparation method of a photo-crosslinking nanofiber in-situ toughening polymer material.

The technical scheme adopted by the invention for solving the technical problems is as follows: a preparation method of a photo-crosslinking nanofiber in-situ toughening polymer material comprises the following steps:

1) preparation of polymer elastomer hybrid pellets: the polymer elastomer mixed granules comprise 0.48-25 wt.% of polymer elastomer, 0.01-2 wt.% of cross-linking agent, 0-2.5 wt.% of photoinitiator and 0.01 wt.% of other auxiliaries, and are added into plastication equipment to be uniformly mixed to obtain a mixture, and then the mixture is added into a granulation extruder to be extruded and granulated;

2) preparing a composite fiber material: sequentially adding the polymer elastomer mixed granules prepared in the step 1), 70.5-99.5 wt.% of matrix polymer and an antioxidant into a screw extruder, carrying out melt blending to obtain a blended melt, wherein the polymer elastomer in the blended melt forms 0.5-10 mu m melt microspheres in the matrix polymer, then enabling the blended melt to pass through a spinneret plate, extruding the blended melt through spinneret holes in the spinneret plate to form melt streams, drawing the melt streams to form a composite fiber material, forming nanofibers with the diameter of less than 400nm in the composite fibers by the polymer elastomer, and forming a composite fiber net or composite fiber cloth by the composite fiber material through a collecting device;

3) preparing a cross-linked composite fiber material: irradiating the composite fiber net or the composite fiber cloth prepared in the step 2) with a light source to crosslink the composite fiber net or the composite fiber cloth to obtain a crosslinked composite fiber material, wherein the light source is LED ultraviolet light with the wavelength of more than 350nm or LED blue light with the wavelength of less than 500 nm;

4) preparing a photo-crosslinking nanofiber in-situ toughening polymer material: adding the crosslinked composite fiber material prepared in the step 3) into a granulating extruder for extruding and granulating to obtain the photo-crosslinked nanofiber in-situ toughening polymer material.

The preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material comprises the step of preparing a polymer elastomer from at least one of natural rubber, ethylene propylene rubber, polybutadiene rubber, styrene butadiene rubber, nitrile butadiene rubber, polyolefin block copolymer, polystyrene thermoplastic elastomer, ethylene-vinyl acetate copolymer, polyurethane elastomer, thermoplastic polyester elastomer, thermoplastic polyamide elastomer, polybutylene adipate terephthalate, polycaprolactone, polybutylene succinate, thermoplastic silicone rubber and fluororubber.

In the preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material, the polymer elastomer is granular or powdery.

In the preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material, the crosslinking agent is one or more of trimethylolpropane triallyl ester, trimethylolpropane trimethacrylate, triallyl isocyanurate, triallyl cyanurate, dicumyl peroxide, thiocyanuric acid, trimethoxy silane and gamma- (methacryloyloxy) propyl trimethoxy silane.

In the preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material, the photoinitiator is one or more of benzophenone, 1-hydroxycyclohexyl phenyl ketone, 4- (dimethylamino) benzophenone, 4' -bis (N, N-dimethylamino) benzophenone, photoinitiator TPO, benzoin dimethyl ether, tetraethyl miktone, isopropyl thioxanthone, 2-chlorothioxanthone and 9-thioxanthone.

According to the preparation method of the photo-crosslinking nano-fiber in-situ toughening polymer material, the matrix polymer is one or two of polyethylene, polypropylene, polylactic acid, polystyrene, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polymethyl methacrylate, polyamide polymer, ABS plastic, polyvinylidene fluoride and polysulfone.

In the preparation method of the photo-crosslinking nano-fiber in-situ toughening polymer material, the other auxiliary agent is an auxiliary agent for a composition suitable for polymer processing, and is selected from a flame retardant, an antistatic agent, a lubricant and/or a mildew preventive.

In the preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material, the light source is LED ultraviolet light with the wavelength of more than 350nm or LED blue light with the wavelength of less than 500nm, and the wavelength is selected from one or two of 365nm, 385nm, 395nm, 405nm, 420nm and 455 nm.

According to the preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material, the drafting mode is one or combination of hot air drafting and cold air drafting.

In the preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material, the temperature of the plastication equipment or the screw extruder is set according to different used materials, and is generally 5-40 ℃ above the highest melting or processing temperature of the polymer matrix and the polymer elastomer.

In the preparation method of the photo-crosslinking nanofiber in-situ toughening polymer material, the temperature of the granulating extruder is set according to different used materials, and is generally 10-60 ℃ above the highest melting or processing temperature of the polymer matrix and the polymer elastomer.

Compared with the prior art, the invention has the following advantages and prominent effects:

the method has the advantages that the polymer elastomer nanofiber is formed in situ, so that the specific surface area of the polymer elastomer is increased, the polymer elastomer nanofiber formed in situ is subjected to photo-crosslinking, the nanofiber form can be kept in subsequent processing, the toughening effect on a matrix polymer material is improved, other mechanical properties of the matrix polymer are guaranteed, and the using amount of the polymer elastomer material can be greatly reduced; the light source is selected to be LED ultraviolet light with the wavelength of more than 350nm or LED blue light with the wavelength of less than 500nm, so that the damage of the ultraviolet light to the polymer matrix can be reduced; good toughening effect can be achieved when the content of the polymer elastomer is less than 3%, and the recycling of the polymer is not influenced by the low content of the polymer elastomer.

Drawings

The invention is further illustrated with reference to the following figures and examples.

FIG. 1 is a stress-strain plot of the material of comparative example 1 of the present invention;

FIG. 2 is a stress-strain plot of the material obtained in comparative example 2 of the present invention;

FIG. 3 is a stress-strain curve of the material obtained in example 3 of the present invention;

FIG. 4 is a graph comparing toughness for different sample materials;

FIG. 5 is a graph comparing tensile strength of different sample materials;

FIG. 6 is a graph comparing the tensile modulus of different sample materials.

Detailed Description

In order to make the technical solutions of the present invention better understood, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[ example 1 ]

Adding the SEBS elastomer, trimethylolpropane triacrylate and benzophenone into plastication equipment according to a certain proportion, uniformly mixing to obtain a mixture, adding the mixture into a granulation extruder, and performing extrusion granulation to obtain a SEBS elastomer blending material; wherein the SEBS elastomer content was 0.48 wt.%, the trimethylolpropane triacrylate content was 0.01 wt.%, the benzophenone content was 0.01 wt.%, and the extruder temperature was set at 210 ℃.

Feeding the prepared mixed material and 99.5 wt.% of polystyrene into a screw extruder for melt blending, wherein the processing temperature is 190 ℃; after the blended melt flows out through a spinneret plate of a spun-bonded non-woven system, the blended melt is cooled by a cold air box and then is drafted by air flow, and the blended melt is collected on a web forming device to prepare a composite fiber web; the spunbond assembly temperature was set at 200 ℃.

And irradiating the composite fiber web under an LED ultraviolet light source with the wavelength of 365nm for 15 s.

And feeding the irradiated fiber web into a feed port of a granulating extruder, setting the temperature of the granulating extruder at 180 ℃, and performing melt extrusion and grain cutting to obtain the SEBS elastomer nanofiber toughened polystyrene material.

[ example 2 ]

Adding the polyolefin elastomer, gamma- (methacryloyloxy) propyl trimethoxy silane and 1-hydroxy-cyclohexyl-phenyl ketone into plastication equipment according to a certain proportion, uniformly mixing to obtain a mixture, and then adding the mixture into a granulation extruder for extrusion granulation to obtain a polyolefin elastomer mixed material; wherein the polyolefin elastomer content was 25 wt.%, the gamma- (methacryloyloxy) propyltrimethoxysilane content was 2 wt.%, the 1-hydroxy-cyclohexyl-phenyl-methanone content was 2.5 wt.%, and the extruder temperature was set at 170 ℃.

Feeding the prepared mixed material and 70.5 wt.% of polyethylene into a screw extruder for melt blending, wherein the processing temperature is 165 ℃; after the blended melt flows out through a melt-blowing spinneret plate, the blended melt is drafted through hot air flow and collected on a web forming device to prepare a composite fiber web; the spinneret assembly temperature was set at 170 ℃ and the hot air temperature 175 ℃.

And irradiating the composite fiber web under an LED ultraviolet light source with the wavelength of 405nm for 10 s.

And feeding the irradiated fiber web into a feed port of a granulating extruder, setting the temperature of the granulating extruder at 160 ℃, and performing melt extrusion and grain cutting to obtain the polyolefin elastomer nanofiber toughened polyethylene material.

[ example 3 ]

Adding ethylene propylene diene monomer, triallyl isocyanurate and photoinitiator TPO into plastication equipment according to a certain proportion, uniformly mixing to obtain a mixture, adding the mixture into a granulation extruder, and performing extrusion granulation to obtain an ethylene propylene diene monomer mixed ingredient; wherein the ethylene propylene diene monomer content is 0, 1 wt.%, 3 wt.% or 5 wt.%, the triallyl isocyanurate content is 0.04 wt.%, the photoinitiator TPO content is 0.04 wt.%, and the extruder temperature is set at 190 ℃.

Feeding the prepared mixed material and polypropylene into a screw extruder for melt blending, wherein the processing temperature is 190 ℃; after the blended melt flows out through a spinneret plate of a spun-bonded non-woven system, the blended melt is cooled by a cold air box and then is drafted by air flow, and the blended melt is collected on a web forming device to prepare a composite fiber web; the spunbond assembly temperature was set at 210 ℃.

And irradiating the composite fiber web under an LED ultraviolet light source with the wavelength of 385nm for 5 s.

And feeding the irradiated fiber web into a feed port of a granulating extruder, setting the temperature of the granulating extruder at 180 ℃, and carrying out melt extrusion and grain cutting to obtain the ethylene propylene diene monomer nano-fiber toughened polypropylene material.

From the comparison of fig. 1, fig. 2 and fig. 3, it can be seen that the photo-crosslinked epdm rubber nanofiber can significantly improve the tensile elongation of the polypropylene material; the non-crosslinked fibrous ethylene propylene diene monomer/polypropylene material has poorer tensile property than the granular ethylene propylene diene monomer/polypropylene material.

From fig. 4, 5 and 6, it can be seen that when the content of the epdm rubber is 3 wt.%, the photo-crosslinking can significantly improve the toughness of the polypropylene material; the rigidity of the EPDM rubber nanofiber reinforced polypropylene material is slightly influenced by photo-crosslinking.

[ example 4 ]

Adding polybutylene adipate terephthalate and trimethylolpropane trimethacrylate into plastication equipment according to a certain proportion, uniformly mixing to obtain a mixture, adding the mixed material into a granulation extruder for extrusion granulation, and preparing a polybutylene adipate terephthalate mixed ingredient; wherein the polybutylene adipate terephthalate content is 3 wt.%, the trimethylolpropane trimethacrylate content is 0.05 wt.%, and the extruder temperature is set at 150 ℃.

Feeding the prepared mixed material and polylactic acid into a screw extruder for melt blending, wherein the processing temperature is 185 ℃; after the blended melt flows out through a spinneret plate of a spun-bonded non-woven system, the blended melt is cooled by a cold air box and then is drafted by air flow, and the blended melt is collected on a web forming device to prepare a composite fiber web; the spunbond assembly temperature was set at 190 ℃.

The composite fiber web was irradiated under an LED light source having a wavelength of 455nm for a period of 25 seconds.

And feeding the irradiated fiber web into a feed port of a granulating extruder, setting the temperature of the granulating extruder at 180 ℃, and performing melt extrusion and granulation to obtain the polybutylene adipate terephthalate nanofiber toughened polylactic acid material.

Comparative example 1

Adding ethylene propylene diene monomer, triallyl isocyanurate and photoinitiator TPO into plastication equipment according to a certain proportion, uniformly mixing to obtain a mixture, adding the mixture into a granulation extruder, and performing extrusion granulation to obtain an ethylene propylene diene monomer mixed ingredient; wherein the ethylene propylene diene monomer content is 0, 1 wt.%, 3 wt.% or 5 wt.%, the triallyl isocyanurate content is 0.04 wt.%, the photoinitiator TPO content is 0.04 wt.%, and the extruder temperature is set at 190 ℃.

Feeding the prepared mixed material and polypropylene into a screw extruder for melt blending, wherein the processing temperature is 190 ℃; the temperature of the granulating extruder is set at 180 ℃, and the ethylene propylene diene monomer particle toughened polypropylene material is prepared after melt extrusion and grain cutting.

Comparative example 2

Adding ethylene propylene diene monomer, triallyl isocyanurate and photoinitiator TPO into plastication equipment according to a certain proportion, uniformly mixing to obtain a mixture, adding the mixture into a granulation extruder, and performing extrusion granulation to obtain an ethylene propylene diene monomer mixed ingredient; wherein the ethylene propylene diene monomer content is 0, 1 wt.%, 3 wt.% or 5 wt.%, the triallyl isocyanurate content is 0.04 wt.%, the photoinitiator TPO content is 0.04 wt.%, and the extruder temperature is set at 190 ℃.

Feeding the prepared mixed material and polypropylene into a screw extruder for melt blending, wherein the processing temperature is 190 ℃; after the blended melt flows out through a spinneret plate of a spun-bonded non-woven system, the blended melt is cooled by a cold air box and then is drafted by air flow, and the blended melt is collected on a web forming device to prepare a composite fiber web; the spunbond assembly temperature was set at 210 ℃.

Feeding the composite fiber web into a feed inlet of a granulating extruder, setting the temperature of the granulating extruder at 180 ℃, and performing melt extrusion and grain cutting to obtain the ethylene propylene diene monomer nano-fiber toughened polypropylene material.

Table 1 tensile properties of the materials of example 1, example 2 and example 4

Parameter(s)	Example 1	Example 2	Example 4
				Tensile Strength (MPa)	52	23	45
Elongation at Break (%)	80	382	116

The above embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and the scope of the present invention is defined by the claims. Various modifications and equivalents may be made by those skilled in the art within the spirit and scope of the present invention, and such modifications and equivalents should also be considered as falling within the scope of the present invention.