JP6482543B2 - Polymer resin composite containing biomass nanofiber, method for producing biomass nanofiber, and method for producing the same - Google Patents

Description

The present invention relates to a polymer resin composite containing biomass nanofibers using biomass resources, a method for producing biomass nanofibers, and a method for producing the polymer resin composite.

In recent years, attention has been focused on the conversion from fossil resources to renewable resources, and in particular, attention has been focused on biomass resources and they have been widely used. Currently, Japan relies on imports for most of its primary resources, but there are also primary resources in the immediate vicinity, such as bamboo and straw. Japan has one of the largest forest area ratios in the world, but due to the drastic decline in domestic production due to the replacement of cheaper overseas biomass, many forests and bamboo forests are not maintained, "Leave bamboo forest" and "Bamboo pollution" are one step in the expansion.

However, from the viewpoint of industrial resources, bamboo is widely distributed mainly in western Japan, and its existence is enormous and has a feature of rapid growth. Moreover, it is very excellent from the viewpoint of materials, and research on composite materials with plastics has been actively conducted, and many improvements in composite properties have been reported. In other words, its use as an industrial resource is an effective solution to the bamboo forest problem, and at the same time is very effective as an alternative resource for fossil fuels.

For the purpose of CO ₂ fixation, research and development of high physical properties materials are being performed based on biomass fibers. Among them, the development of cellulosic nanocomposites is progressing rapidly. As basic elements, attention has been focused on nano-structured fibers with high strength, high elasticity, and low thermal expansion. In this nanostructured fiber, how 1) nanostructured fiber can be easily obtained, 2) its function is not lost and its function can be exerted greatly, 3) especially organic polymers and Developed with a focus on whether it is easy to process industrially, such as composites, or 4) to demonstrate that nanostructured fibers are not lost during processing such as composites and that they are highly dispersible It is requested to do.

Among them, various technologies have been published for the production of nanofibers for lignocellulose and a composite material with organic polymer from cellulose-based fiber materials such as bamboo, wood pulp and kenaf.
In addition, plant fibers such as pulp can be defibrated to make microfibrils. And the technique which combines the fiber and the organic polymer which have the obtained microfibril is examined.

In conventional compounding technology, fibers are defibrated to a nano size using a grinder, mixer, etc., and nano-sized fiber surfaces treated with chemicals are mixed with general-purpose resins such as PP and PE for compatibility. It requires a three-stage process of improving and performing surface modification to prevent fiber re-aggregation during molding.

For example, by using a hypochlorous acid-based oxidizing agent to control the repulsion of nanofibers to obtain highly dispersible fibers (Patent Document 1), the negative charge introduced on the microfibril surface is reduced. A technique of attracting repulsive force between microfibrils due to the presence of a carboxyl group and stably dispersing in a dispersion (Patent Document 2) is disclosed.

However, none of these techniques simplify the above-described three-stage process. In addition, it is difficult to mold the nanofibers having microfibrils obtained by highly dispersing them in a polymer resin.

On the other hand, the present inventors processed the raw material derived from oil palm with superheated steam to obtain biomass powder, and further blended the biomass powder with a prepolymer such as a thermoplastic resin and melt molded it to perform biomass composite molding. A technique for obtaining a body is disclosed (Patent Document 3). At this time, a biomass powder having 50% by mass or more in the range of the major axis of 1 to 500 μm is obtained.

JP 2008-1728 A JP 2009-293167 A WO2013 / 076960 pamphlet

However, the technique described in Patent Document 3 has not yet reached a biomass powder with a nano-order size.
The present invention has been made in view of such circumstances, and an object thereof is to provide a method for producing nano-order biomass nanofibers from biomass raw materials, a polymer resin composite using the method, and a method for producing the same.

The polymer resin composite containing biomass nanofibers according to the first invention that meets the above-mentioned object comprises 100 parts by mass of biomass nanofibers having a diameter of 50 to 500 nm , 3 to 12% by mass of a polyvinyl alcohol aqueous solution, and maleic anhydride-modified polypropylene. Or 50 to 200 parts by mass of a dispersant composed of low molecular weight polycaprolactone and 400 to 3500 parts by mass of a polymer resin.

In the polymer resin composite containing biomass nanofibers according to the first invention, the biomass to be the biomass nanofibers is preferably composed of one or more selected from bamboo, Elianthus, oil palm, and straw.

In the method for producing biomass nanofibers according to the second invention, the biomass is heated to 180-230 ° C. with superheated steam to obtain biomass fibers, and a multi-screw extruder is used. A dispersing agent comprising a mass% polyvinyl alcohol aqueous solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone was blended , extruded while kneading at a processing temperature of 10 to 120 ° C. and an axial rotation speed of 50 to 150 rpm, and a diameter of 50 to Obtaining biomass nanofibers of 500 nm .

In the method for producing biomass nanofibers according to the second invention, the heat treatment is preferably performed with superheated steam at 180 to 230 ° C. for 1 to 5 hours.

In the method for producing biomass nanofibers according to the second invention, it is preferable to blend 50 to 200 parts by mass of the dispersant with respect to 100 parts by mass of the biomass.

The method for producing a polymer resin composite containing biomass nanofibers according to the third invention is a method for producing a polymer resin composite containing biomass nanofibers according to the first invention, and relates to the second invention It has the process of mix | blending polymer resin with the said biomass nanofiber obtained by the manufacturing method of biomass nanofiber, and extrusion-molding with a multi-screw extruder, and obtaining the polymer resin composite containing biomass nanofiber.

In the method for producing a polymer resin composite containing biomass nanofibers according to the third invention, the polymer resin is preferably a thermoplastic resin or a thermosetting resin.

In the method for producing a polymer resin composite containing biomass nanofibers according to the third invention, a processing temperature in the multi-screw extruder for forming the polymer resin composite is 80 to 220 ° C., and a processing pressure is It is preferably 50 MPa or less and the shaft rotation speed is 15 to 50 rpm.

A method for producing a polymer resin composite containing biomass nanofibers according to a fourth invention is a method for producing a polymer resin composite containing biomass nanofibers according to the first invention, wherein a defibrating unit is provided upstream. Using a multi-screw extruder having a melt kneading part formed on the downstream side, obtaining the biomass nanofibers according to the second invention in the defibrating part, and biomass nanofibers in the melt kneading part The process of manufacturing the polymer resin composite containing is performed continuously.

A method for producing a polymer resin composite containing biomass nanofibers according to a fifth invention is a method for producing a polymer resin composite containing biomass nanofibers according to the first invention, wherein a plurality of connected multiple A step of obtaining biomass nanofibers according to the second invention in a multi-screw extruder located on the upstream side of a shaft extruder, and a downstream side of the plurality of connected multi-screw extruders The process of obtaining the polymer resin composite containing biomass nanofibers is continuously performed using a multi-screw extrusion molding machine located in the area.

In the method for producing a polymer resin composite containing biomass nanofibers according to the fourth and fifth inventions, the multi-screw extruder is preferably a twin-screw extruder.

Since the polymer resin composite containing biomass nanofibers according to the first invention is formed by mixing biomass nanofibers and polymer resin, a complex molded product having strength by compression molding or injection molding is used. Can be obtained.
Here, the aqueous polyvinyl alcohol solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone acts as a substance that enhances the compatibility. That is, no matter how strong the biomass fiber is, the polymer resin (for example, PP) and the biomass fiber have completely different properties. Does not demonstrate. Therefore, a compatibilizing agent that appropriately increases compatibility (adhesion) at the interface is indispensable. Therefore, in the first invention, the above-described compatibilizing agent (that is, a dispersing agent) is added in order to express the fiber reinforcement of the biomass fiber in the physical properties of a normal polymer resin.

Further, the powder becomes invisible when its cross-sectional diameter becomes smaller than the wavelength of visible light (370 to 780 nm). That is, transparency appears in the polymer resin composite (resin molded product). In addition, when the cross-sectional diameter of the fibrous biomass fiber is reduced, the fiber is flexible and the aspect ratio (length / cross-sectional area ratio) is increased, resulting in entanglement with each other. The mechanical strength is improved.

The method for producing biomass nanofibers according to the second invention includes, for example, a process of obtaining biomass fibers by heat-treating one or more biomass selected from bamboo, Elianthus, oil palm and straw with superheated steam; Using an extruder and mixing biomass fiber with polyvinyl alcohol aqueous solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone and extruding while kneading to obtain biomass nanofibers. Can be suitably obtained.

According to a third aspect of the present invention, there is provided a method for producing a polymer resin composite containing biomass nanofibers, wherein a polymer resin is blended with biomass nanofibers obtained by the method for producing biomass nanofibers and extruded with a multi-screw extruder. A polymer resin composite comprising biomass nanofibers having a high mechanical property in which the biomass nanofibers are highly dispersed in the polymer resin because it has a step of forming and obtaining a polymer resin composite containing biomass nanofibers. Can be suitably obtained.

Moreover, the manufacturing method of the polymeric resin composite containing the biomass nanofiber which concerns on 4th, 5th invention uses the multi-screw extruder by which one or more were connected, and one multi-screw extruder was used. A process of obtaining biomass nanofibers in a multi-screw extruder located upstream or among a plurality of linked multi-screw extruders, and downstream of one multi-screw extruder or In order to continuously perform the process of obtaining a polymer resin composite containing biomass nanofibers in a multiaxial extruder located downstream of a plurality of connected multiaxial extruders, The polymer resin composite containing it can be obtained by an efficient process. In addition, when the obtained biomass nanofiber is once taken out from the apparatus and then blended with the polymer resin in another apparatus, there is a possibility that the biomass nanofiber to be blended may agglomerate. There is no.

It is explanatory drawing which shows schematic structure of the twin-screw extruder used by the experiment example and the comparative example. It is the SEM photograph which solidified the polymer resin composite sample containing the biomass nanofiber obtained in Experimental example 5 with liquid nitrogen, and examined the section by SEM. It is the FE-SEM photograph which examined the freeze-dried material of the biomass nanofiber obtained in Experimental Example 6 with FE-SEM.

Next, an embodiment of the present invention will be described with reference to the drawings. First, the manufacturing method of the biomass nanofiber which concerns on one Example of this invention is demonstrated.
The method for producing biomass nanofibers according to this example includes a step of obtaining biomass fibers by heating one or more biomass selected from bamboo, Elianthus, oil palm and straw with superheated steam, and a multi-screw extruder. And a step of blending biomass fiber with a polyvinyl alcohol aqueous solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone and extruding while kneading to obtain biomass nanofibers.

Bamboo and Eliansus have good productivity (growth) efficiency and are preferable as biomass natural resources. In addition, Elianthus can be produced permanently and CO ₂ fixation is extremely high. By planting it as a natural biomass resource, deforestation reduces its ability to fix carbon on the earth, resulting in global warming. High ability to prevent progress. Oil palm and straw contribute to the reduction of the amount of industrial unused waste by using it as biomass resources.

An appropriate reactor can be used as an apparatus for heat treatment with superheated steam.
The temperature of the superheated steam is preferably 180 to 230 ° C. The heat treatment time is preferably about 1 to 5 hours, although it depends on the apparatus conditions and the conditions of the biomass to be treated. The obtained biomass fiber is crushed, crushed or sieved to an appropriate size that can be easily processed in a multi-screw extruder.

As the multi-screw extruder, one having three or more axes may be used, but a twin-screw extruder is sufficient and preferable. A multi-screw extruder including a twin-screw extruder rotates a temperature-adjustable cylinder, a plurality of shafts (hereinafter referred to as screws) rotatably arranged in the cylinder, and a plurality of screws. A rotation drive mechanism including a motor and a speed reducer (not shown). A supply port for biomass (fiber) and a dispersant (polyvinyl alcohol aqueous solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone) is disposed on the upstream side of the cylinder.

The screw length / screw diameter ratio (L / D) of the multi-screw extruder can be about 20-60. It is preferable that the processing temperature in a multi-screw extruder is 10 to 120 ° C., the processing pressure is 50 MPa or less, and the shaft rotation speed is 50 to 150 rpm. Moreover, it is preferable that processing time is about 30 to 60 minutes.
Biomass is sheared by the kneading disk part or screw part of the multi-screw extruder, and biomass nanofibers are obtained. The multi-screw extruder not only performs heating and kneading in each fractionated zone, but can also remove volatile components by decompression.

Bamboo, Elianthus, oil palm and straw are biomass that retains a tough structure with hemicellulose, and therefore, fiberization is usually not easy. In this example, these biomasses are pulverized into suitable dimensions that are easy to process with a multi-screw extruder, for example, about 1 to 3 mm in width and about 1 to 5 cm in length, and then charged into the multi-screw extruder. At this time, a polyvinyl alcohol aqueous solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone is blended together with biomass.

Aqueous polyvinyl alcohol, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone acts as a dispersant that finely disperses biomass fibers and improves interfacial compatibility. In addition to these materials, a material having a viscosity range of 1000 to 2500 cp, which can be prepared by controlling the amount of water, heating, and molecular weight, and a material that is well entangled with fibers in the extruder can be used as a dispersant. In the case of using a polyvinyl alcohol aqueous solution, the concentration of the aqueous solution is 3-12% by mass having a good viscosity that affects defibration, and a 9% by mass polyvinyl alcohol aqueous solution is particularly preferable.
Preferably, 50 to 200 parts by mass of an aqueous polyvinyl alcohol solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone is added to 100 parts by mass of biomass. Thereby, biomass nanofibers having dimensions of the order of several tens to several hundreds of nanometers are obtained.

Next, the manufacturing method of the polymeric resin composite containing the biomass nanofiber which concerns on the 1st Example of this invention is demonstrated.
The method for producing a polymer resin composite containing biomass nanofibers according to the present example is prepared by mixing a polymer resin with biomass nanofibers obtained by the above-described biomass nanofiber production method and extruding with a multi-screw extruder. And a step of obtaining a polymer resin composite containing biomass nanofibers. The multi-screw extruder has basically the same configuration as that of the multi-screw extruder, but further includes a mold (may be separately provided) for molding into a target shape. It is preferable that the processing temperature of the multi-screw extruder (for example, a twin-screw extruder) is 80 to 220 ° C., the processing pressure is 50 MPa or less, and the shaft rotation speed is 15 to 50 rpm.

The kind of the polymer resin is not particularly limited, but is preferably a thermoplastic resin or a thermosetting resin. It is preferable to blend 400 to 3500 parts by mass of the polymer resin with respect to 100 parts by mass of the biomass nanofibers. Thereby, biomass nanofibers are highly uniformly dispersed in the polymer resin, and a polymer resin composite containing biomass nanofibers having high mechanical properties is obtained.

In addition, a method for producing a polymer resin composite containing biomass nanofibers according to a second embodiment of the present invention includes a multi-screw extruder (specifically, a twin-screw extruder) in which one or more are connected. And the step of obtaining biomass nanofibers with a multi-screw extruder located upstream of one multi-screw extruder or upstream of a plurality of connected multi-screw extruders, and A step of obtaining a polymer resin composite containing biomass nanofibers in a multi-screw extruder located downstream of one multi-screw extruder or downstream of a plurality of connected multi-screw extruders Are performed continuously.
When one multi-screw extruder is used, a defibrating unit is formed on the upstream side, a melt-kneading unit is formed on the downstream side, and biomass nanofibers are produced in the defibrating unit. Manufacture of polymer resin composites containing nanofibers.

Thereby, the polymer resin composite containing biomass nanofibers can be obtained by an efficient process. In addition, when the obtained biomass nanofibers are once taken out from the apparatus and then blended with the polymer resin in another apparatus, there is a risk that the biomass nanofibers to be blended may agglomerate, but according to this example, There is no fear.

Polymer resin composites containing biomass nanofibers obtained by the method for producing polymer resin composites containing biomass nanofibers according to the first and second embodiments are used for home appliances, housings for mobile phones, automobiles, etc. Applications in a wide range of fields such as interior materials, building materials, packaging materials, and resin reinforcements for 3D printers are expected.
In addition, it is a preferable embodiment to obtain a molded product having a desired complicated shape by compression molding or injection molding using, for example, a pellet-shaped polymer resin composite obtained by a multi-screw extrusion shaping machine as a raw material.

[Experimental example]
Hereinafter, although the experiment example and comparative example which clarified the effect | action and effect of this invention are demonstrated, this invention is not limited to these experiment examples.
First, the evaluation method of the polymer resin composite containing the obtained biomass nanofiber is demonstrated.

<Tensile test>
A polymer resin composite containing biomass nanofibers was cut into strips (length: 40 mm, width: 5 mm, thickness: 0.3 mm) to obtain tensile test pieces. In the tensile test, tensile strength, tensile elastic modulus, and elongation were calculated from the obtained stress-strain curve using an IMC-18E0 type tensile compression tester manufactured by Imoto Seisakusho according to JUSK-6732.

<Morphological observation>
For the sample for observation, a specimen of a polymer resin composite containing biomass nanofibers was frozen with liquid nitrogen, and the fracture surface was observed with a scanning electron microscope (SME, Hitachi, S-3000N). The state was observed with a field emission electron microscope (FE-SEM, Hitachi, S-5200).

(Explanation of devices used in comparative examples and examples)
A biaxial extruder 10 (manufactured by Imoto Seisakusho: biaxial kneading extruder 160B, rotating in the same direction, screw diameter 20 mm, L / D = 25, vent number 2) shown in FIG. 1 was used. The twin-screw extruder 10 includes an upstream defibrating unit and a downstream melt-kneading unit. The defibrating unit has a steam-treated biomass and an inlet (supply port) 11 for an aqueous polyvinyl alcohol solution as a dispersant, and the melt-kneading unit has an inlet (vent port) for a polymer resin (polymer material). ) 12 and a vent port 13 for degassing volatile components. In FIG. 1, reference numeral 14 denotes a temperature-adjustable cylinder, and 15 denotes a plurality of screws (shafts) arranged rotatably in the cylinder 14. On the further downstream side of the vent port 13, a mold is connected to the cylinder 14.
In the following experimental examples and comparative examples, this twin-screw extruder 10 was used unless otherwise specified.

(Comparative Example 1)
Polypropylene (PP, Nippon Polypropylene Co., Ltd., FY6 MFR2.5) is put into the inlet of a twin screw extruder, extruded at a screw speed of 15 rpm and a cylinder temperature of 200 ° C. for 5 minutes, and a molded product sample Got.

(Experimental example 1)
Bamboo was cut into dimensions that could be easily treated, put into a reactor (superheated steam treatment apparatus NHL-1 manufactured by Naomoto Kogyo Co., Ltd.), and treated with superheated steam at 210 ° C. for 3 hours. The preliminarily defibrated biomass was further pulverized using a crusher (wood crusher manufactured by Fujitex Co., Ltd.) to obtain crushed bamboo powder (width 1 to 3 mm, length 1 to 5 cm). The ground bamboo powder in the other experimental examples below was also obtained by this method.

An aqueous solution (viscosity: 1800 cp) of polyvinyl alcohol (PVA Tokyo Kasei Co., Ltd., saponification degree 80 mol%: polymerization degree 2000) with a concentration of 9% by mass is used at 80 ° C. And stirred for 1 hour at 500 rpm. In addition, using a digital viscometer (Brookfield, DV-I prime), the value after 90 seconds at a temperature of 22 ° C. and a rotation speed of 10 rpm was taken as the viscosity of the aqueous solution.

A polyvinyl alcohol aqueous solution was pre-blended at a rate of 10 g with respect to 10 g of the pulverized bamboo powder, charged from the supply port of the twin-screw extruder, and defibrated at room temperature and at a screw rotation speed of 95 rpm for 1 h. Further, in the melt-kneading part, the screw rotation speed is 15 rpm, the cylinder temperature is 200 ° C., 180 g of polypropylene (PP Nippon Polypropylene Co., Ltd., FY6 MFR = 2.5) is introduced from the upstream vent port, and the downstream vent port The water was deaerated at 50 KPa and extruded over 5 minutes to obtain a polymer resin composite sample containing biomass nanofibers.

(Experimental example 2)
Two twin screw extruders (first extruder and second extruder) were connected and used.
The first extruder was exclusively used for defibration and was processed under the same processing conditions as in Experimental Example 1 to obtain biomass nanofibers. The obtained biomass nanofibers are kept in a dispersed state in the PVA aqueous solution, and polypropylene is introduced in the second extruder, the screw rotation speed is 15 rpm, the cylinder temperature is 200 ° C., and the moisture is 50 KPa from the downstream vent port. Degassing and extrusion molding over 5 minutes gave a polymer resin composite sample containing biomass nanofibers.

(Experimental example 3)
Experimental Example 1 except that the maleic anhydride-modified polypropylene (MA-PP, Sanyo Chemical Industries, Yumex 1010) was used instead of the 9% by weight polyvinyl alcohol aqueous solution of Experimental Example 1, and the cylinder temperature was defibrated at room temperature. A polymer resin composite sample containing biomass nanofibers was obtained by treatment under the same conditions.

(Experimental example 4)
The polymer resin composite sample containing biomass nanofibers was obtained at a cylinder temperature of 100 ° C. and a screw rotation speed of 100 rpm, and the biomass rotation speed was 25 rpm. A polymer resin composite sample was obtained.

(Comparative Example 2)
100 g of high molecular weight polycaprolactone (H-PCL, ALDRICH, molecular weight: 90000, pellet form) is put into an inlet of an extruder, and is extruded at a screw speed of 15 rpm and a cylinder temperature of 200 ° C. for 5 minutes. A molded body sample was obtained. The comparative example 2 is comparison target data of the fifth embodiment.

(Experimental example 5)
10 g of pulverized bamboo powder is replaced with a polyvinyl alcohol aqueous solution and 10 g of low molecular weight polycaprolactone (L-PCL, Daicel Chemical Industries, Ltd., PLACEL L220AL, molecular weight: 2000, liquid) is pull-blended. The product was put into the inlet and defibrated at the defibrating part for 1 h at a cylinder temperature of 60 ° C. and a screw rotation speed of 95 rpm. Next, in the melt-kneading part, 100 g of high molecular weight polycaprolactone (H-PCL, ALDRICH, molecular weight: 90000, pellet form) is charged, extruded at a cylinder temperature of 100 ° C. and a screw rotation speed of 15 rpm for 5 minutes, and biomass. A polymer resin composite sample containing nanofibers was obtained.
An SEM photograph of a polymer resin composite sample containing biomass nanofibers is shown in FIG. It can be seen that biomass nanofibers of about 300 to 500 nm that look like white threads are dispersed in the polymer resin.

(Comparative Example 3)
The same treatment as in Experimental Example 1 was performed except that polyvinyl alcohol was not used. The pulverized bamboo powder was not sufficiently defibrated, and therefore, subsequent molding treatment could not be performed.

(Experimental example 6)
Fiber nanofibers were obtained by defibration with a twin screw extruder under the same conditions as in Experimental Example 1. In order to remove excess PVA, which is a water-soluble resin, water was added for dilution, and the supernatant biomass nanofibers were lyophilized using a freeze dryer (Tokyo Science Machine FDU-1200). Next, it was processed at the same conditions as in Experimental Example 1 except that it was blended at a ratio of 90 g of polypropylene to 10 g of crushed lyophilized powder, put into a twin-screw extruder, and then processed under the same conditions as in Experimental Example 1. A molecular resin composite sample was obtained.
An FE-SEM photograph of the freeze-dried biomass nanofiber is shown in FIG. It can be seen that the network is formed by intertwining the biomass nanofibers.
Table 1 shows the blending ratio (weight ratio) of each component of the composites or molded bodies of the above experimental examples and comparative examples. Table 2 shows the mechanical properties of the sample or the molded body sun composite pull.

From Table 2, it can be seen that in Examples 1 to 4 and 6, composites having excellent tensile strength are obtained. In particular, in Experimental Example 4, as a result of applying heat at the time of defibration, the contact thermal resistance between the solid surfaces was reduced, MA-PP was more closely adhered to the fiber surface, and the compatibility with PP increased, Tensile strength was greatly improved.
On the other hand, in Experimental Example 5, the elastic modulus was improved by 3 times or more.

The present invention is not limited to the above examples and experimental examples, and can be improved and changed without departing from the gist of the invention.

A polymer resin composite containing biomass nanofibers according to the present invention, a method for producing biomass nanofibers, and a method for producing the polymer resin composite can form a more precise and strong polymer resin composite, This polymer resin composite can be manufactured at low cost.

10: biaxial extruder, 11: input port, 12: input port, 13: vent port, 14: cylinder, 15: screw

Claims (9)

100-mass parts of biomass nanofibers having a diameter of 50-500 nm, 50-200 parts by weight of a dispersant comprising 3-12% by weight of a polyvinyl alcohol aqueous solution, maleic anhydride-modified polypropylene, or low molecular weight polycaprolactone, and a polymer resin 400- A polymer resin composite containing biomass nanofibers, comprising 3500 parts by mass . 2. The polymer resin composite comprising biomass nanofibers according to claim 1, wherein the biomass as the biomass nanofibers comprises one or more selected from bamboo, Elianthus, oil palm, and straw. A polymer resin composite containing nanofibers. A step of heat-treating biomass with superheated steam at 180 to 230 ° C. to obtain biomass fibers;
Using a multi-screw extruder, 3 to 12% by mass of a polyvinyl alcohol aqueous solution, a maleic anhydride-modified polypropylene, or a low molecular weight polycaprolactone dispersant is blended with the biomass fiber , the processing temperature is 10 to 120 ° C., and the shaft is rotated. Extruding while kneading at a speed of 50 to 150 rpm to obtain biomass nanofibers having a diameter of 50 to 500 nm ;
A method for producing biomass nanofibers, comprising: A step of obtaining a polymer resin composite containing biomass nanofibers by blending a polymer resin with the biomass nanofibers obtained by the method for producing biomass nanofibers according to claim 3 and extruding with a multi-screw extruder. A method for producing a polymer resin composite comprising biomass nanofibers according to claim 1 or 2 . 5. The method for producing a polymer resin composite containing biomass nanofibers according to claim 4 , wherein the polymer resin is a thermoplastic resin or a thermosetting resin. Body manufacturing method. The method for producing a polymer resin composite containing biomass nanofibers according to claim 4 or 5 , wherein a processing temperature in the multi-screw extruder for forming the polymer resin composite is 80 to 220 ° C, a processing pressure. Is 50 MPa or less, and a shaft rotational speed is 15-50 rpm, The manufacturing method of the polymer resin composite containing the biomass nanofiber characterized by the above-mentioned. A process of obtaining biomass nanofibers according to claim 3 in the defibrating unit using one multi-screw extruder in which a defibrating unit is formed on the upstream side and a melt kneading unit is formed on the downstream side, and the melt kneading unit The method for producing a polymer resin composite containing biomass nanofibers according to claim 1 or 2, wherein the step of producing a polymer resin composite containing biomass nanofibers is continuously performed. A step of obtaining biomass nanofibers according to claim 3 in a multi-screw extruder located upstream of a plurality of connected multi-screw extruders, and the plurality of connected multi-screw extruders 3. The biomass nanofiber according to claim 1 or 2, wherein the step of obtaining a polymer resin composite containing biomass nanofiber is continuously performed by a multi-screw extrusion molding machine located on the downstream side of A method for producing a polymer resin composite. 9. The method for producing a polymer resin composite containing biomass nanofibers according to claim 7 or 8, wherein the multi-screw extruder is a twin-screw extruder. A method for producing a polymer resin composite containing fibers.