KR20230121290A - Composite material containing biodegradable polymer, manufacturing method thereof, and melt blown nonwoven fabric containing the composite material - Google Patents

Abstract

The present invention is a biodegradable polymer resin; cellulosic fibers; viscosity modifier; And an acidic catalyst, wherein the cellulose fiber relates to a composite material comprising a biodegradable polymer that is a surface-modified cellulose fiber, and has excellent melt flow characteristics of the resin, so that it can be manufactured into fine fibers, and is a meltblown nonwoven fabric. It can be manufactured in a furnace, and the prepared meltblown nonwoven fabric has excellent mechanical properties and web uniformity, so it can exhibit stable barrier properties when used as a filter.

Description

Composite material containing biodegradable polymer, manufacturing method thereof, and melt blown nonwoven fabric containing the composite material}

The present invention relates to a composite material containing a biodegradable polymer, a manufacturing method thereof, and a meltblown nonwoven fabric containing the composite material.

Compared to general spunbond nonwoven fabrics, nonwoven fabrics produced by the meltblown method are superior in flexibility, uniformity, and compactness because the fibers constituting the nonwoven fabric can be thinned.

For this reason, meltblown nonwoven fabrics, either alone or laminated with other nonwoven fabrics, can be used in filters such as liquid filters and air filters, sanitary materials, medical materials, agricultural coating materials, civil engineering materials, building materials, oil adsorption materials, automobile materials, electronic materials, and separators. , clothing, packaging materials, etc.

As fibers constituting the meltblown nonwoven fabric, fibers of thermoplastic resins such as polypropylene and polyethylene are known.

In general, filters are used for the purpose of collecting particulates present in a liquid or gas and removing the particulates from the liquid or gas. It is known that the filter's efficiency of collecting fine particles (hereinafter also referred to as "collecting efficiency") tends to be excellent when the average fiber diameter of the fibers of the nonwoven fabric constituting the filter is small and the specific surface area is large. It is also known that the smaller the particle diameter of the fine particles, the lower the collection efficiency.

As environmental issues have emerged due to the recent increase in the use of disposable products, and the need for the use of eco-friendly polymer materials has increased throughout the industry, research for replacing conventional polymer materials has been actively conducted.

In particular, biodegradable polymer materials are actively being studied as a material that can replace conventional polymer materials.

However, in the conventional fiber and nonwoven fabric manufacturing process using biodegradable polymer materials, it is difficult to make melt spinning workability and technically fine fibers, and mechanical properties are low or web uniformity is low, resulting in stable barrier properties when used as filters. There is a problem that is difficult to express.

In order to solve these problems, it is necessary to develop a composite material containing an improved biodegradable polymer.

(Patent Document 1) KR 10-2020-0047703 A1

An object of the present invention is to provide a composite material containing a biodegradable polymer, a manufacturing method thereof, and a meltblown nonwoven fabric including the composite material.

Another object of the present invention is to provide a composite material capable of producing a meltblown nonwoven fabric using a biodegradable polymer and a method for manufacturing the same, wherein the composite material has excellent melt flow characteristics of the resin, so that fine fibers can be manufactured. characterized as possible.

Another object of the present invention is to use a composite material containing a biodegradable polymer and when manufacturing a meltblown nonwoven fabric, the prepared meltblown nonwoven fabric has excellent mechanical properties and web uniformity, so that it can be stably blocked when used as a filter, etc. It is to provide a composite material that can show the sex.

In order to achieve the above object, the present invention is a composite material comprising a biodegradable polymer, a biodegradable polymer resin; cellulosic fibers; viscosity modifier; and an acidic catalyst, wherein the cellulose fibers may be surface-modified cellulose fibers.

The biodegradable resin is polylactic acid, poly(Butylene Succinate), polyhydroxyalkanoate, polybutylene adipate-co-terephtalate ) and mixtures thereof.

The biodegradable resin may have a melt index (MI) of 5g/10min to 50g/10min at 190°C.

The cellulose fibers may be surface-modified with a silane compound.

The viscosity modifier is a peroxide, and the peroxide is tert-butyl peroxide (2.5-Dimethyl 2.5-Di(Tert-butylperoxy)hexane, DTBH), benzoyl peroxide, bisdicyclobenzoyl peroxide, dicmyl peroxide, and mixtures thereof It can be selected from the group consisting of.

The acidic catalyst is hydroxyaluminum bis(2,2-methylene-bis(4,6-di-tert-butylphenyl) phosphate (Hydroxyaluminum bis(2,2-methylene-bis(4,6-di-tert-butylphenyl) )phosphate)).

Method for producing a composite material comprising a biodegradable polymer according to another embodiment of the present invention includes the steps of: 1) modifying cellulose fibers to prepare surface-modified cellulose fibers; 2) preparing a master batch by melting and mixing the biodegradable resin, the surface-modified cellulose fibers and the viscosity modifier of step 1) in a twin-screw extruder, and reaction-extruding; 3) preparing pellets for a composite material by melting and mixing the master batch, the biodegradable resin, and the acidic catalyst of step 2) in a twin screw extruder, and extruding the mixture; and 4) preparing a composite material by drying the composite material pellets.

In step 1), the solution in which the cellulose is mixed is stirred, the silane compound is added, and stirred for 4 to 6 hours at a stirring speed of 650 to 850 rpm, and then at 95 to 115 ° C. at a stirring speed of 700 to 850 rpm for 5 to 15 minutes. It is possible to prepare surface-modified nano-cellulose fibers by stirring while.

The silane compound may be prepared by mixing a silane compound and distilled water in a weight ratio of 1:5, mixing an organic acid, and stirring at a stirring speed of 250 to 390 rmp for 20 to 30 minutes.

The silane compound is aminopropyltriethoxysilane, aminopropyltrimethoxysilane, amino-methoxysilane, phenylaminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropyltridimethoxysilane, γ-aminopropyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyldiethoxy Silane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(methoxyethoxy)silane, di-, tri- or tetraalkoxysilane, vinylmethoxysilane, vinyltrimethoxysilane, vinylepoxysilane, vinyl Triepoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, chlorotrimethyl Silane, trichloroethylsilane, trichloromethylsilane, trichlorophenylsilane, trichlorovinylsilane, mercaptopropyltriethoxysilane, trifluoropropyltrimethoxysilane, bis(trimethoxysilylpropyl)amine, bis (3-triethoxysilylpropyl)tetrasulfide, bis(triethoxysilylpropyl)disulfide, (methacryloxy)propyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, and combinations thereof.

A meltblown nonwoven fabric according to another embodiment of the present invention may include the composite material.

The present invention has excellent melt flow characteristics of the resin, so that it can be manufactured into fine fibers, so that it can be manufactured into a meltblown nonwoven fabric, and the manufactured meltblown nonwoven fabric has excellent mechanical properties and web uniformity. When used, it can show stable barrier properties.

1 is an experimental result for the dispersibility of surface-modified nano-cellulose fibers according to an embodiment of the present invention.
Figure 2 is an experimental result for the dispersibility of nano-cellulose fibers according to an embodiment of the present invention.
Figure 3 is an experimental result for the dispersibility of the surface-modified nano-cellulose fibers according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be embodied in many different forms and is not limited to the embodiments described herein.

As used herein, the term "meltblown fiber" is a nonwoven fabric including fibers or microfibers formed by extruding a molten processable polymer together with a high-temperature, high-speed compressed gas through a plurality of fine capillaries. Here, the capillary may be variously changed such as circular, polygonal including triangular and quadrangular, and star-shaped. As an example, the high temperature and high speed compression body can attenuate the molten thermoplastic polymer material into microfibers, reducing the diameter to about 0.3 to 10 μm. Meltblown microfibers may be discontinuous fibers or continuous fibers. 70 to 80%, or 70 to 90% of the meltblown microfibers may have a diameter of 3 μm or less. 10, 20, and 30% of the meltblown microfibers may have a diameter of 1 μm or less.

As used herein, the term "spunbond nonwoven fabric" refers to a fibrous web manufactured by stretching a plurality of fine-diameter filaments extruded through a capillary tube using a high-temperature tube and stacking them.

In general, it is known that webs or nonwoven fabrics containing meltblown fibers can be used for purposes such as sound absorption, sound insulation, heat insulation, filtration of particulates, and/or water/oil separation. there is. In particular, it has often been found to be advantageous to simultaneously use synthetic resins from different polymers.

To produce the conventional meltblown nonwoven fabric, it can be formed by extruding a molten polymer through a die and then attenuating the resulting fibers with a high-temperature, high-velocity gas stream.

It is known that the nonwoven fabric produced by the melt blown method has excellent flexibility, uniformity and compactness, and must be manufactured using synthetic fibers in order to realize the above physical properties.

As described above, as the use of plastic materials is rapidly increasing, the need for use of eco-friendly polymers is increasing throughout the industry, and in particular, research on biodegradable polymers is being actively conducted.

The biodegradable polymer is one of a kind of polymer that produces natural by-products such as carbon dioxide, nitrogen, water, biomass, and inorganic salts that can be chemically degraded after use. These polymers are found naturally or are produced synthetically, and consist of ester, amide, and ether functional groups.

Specifically, types of biodegradable polymers include natural biodegradable polymers, natural synthetic polymers, and microbially produced polymers. More specifically, starch, chitin, and cellulose extracted from grains are natural polymers, and polylactic acid (PLA) , PGA, PCL, etc. are synthetic biodegradable polymers. Microbial-produced polymers are known as polyhydroxyalkanoate (PHA) and PHB, which are synthesized and accumulated by microorganisms as energy storage materials in the presence of a carbon source and limited nutrients.

Among them, PLA is cheaper than other biodegradable polymers and has excellent physical properties.

However, due to its high molecular weight and viscosity, PLA has a problem in that it is difficult to use in the manufacturing process of fibers and nonwoven fabrics requiring barrier properties.

In particular, there are problems in that melt spinning workability and technically finer fiber are difficult, and even after manufacturing, mechanical properties are low or web uniformity is poor, making it difficult to show stable barrier properties.

In the present invention, a composite material is prepared using a biodegradable polymer resin, and the composite material can be melt-blown into melt-blown fibers, and the manufactured fibers have excellent mechanical properties and web uniformity, so that nonwoven fabrics, etc. It is characterized by being able to be used as a

Specifically, the composite material comprising the biodegradable polymer of the present invention is a biodegradable polymer resin; cellulosic fibers; viscosity modifier; and an acidic catalyst, wherein the cellulose fibers may be surface-modified cellulose fibers.

The biodegradable resin is polylactic acid, poly(Butylene Succinate), polyhydroxyalkanoate, polybutylene adipate-co-terephtalate ) and mixtures thereof, preferably polylactic acid (PLA), but is not limited to the above examples.

The biodegradable resin may have a melt index (MI) of 6 g/10 min to 60 g/10 min at 190 °C, preferably a melt index (MI) of 10 g/10 min to 50 g/10 min at 190 °C, more preferably Preferably, the melt index (MI) may be 30 g/10 min to 40 g/10 min at 190 °C. As described below, the melt index determines whether melt spinning is possible when manufacturing a composite material, and the higher the melt index, the smaller the molecular weight of the polymer and the better the flowability. The biodegradable resin within the range of the melt index When manufactured as a composite material using , it can be manufactured as a meltblown fiber, can maintain stability even during long-term storage, and can exhibit excellent physical properties.

The cellulose fibers may be surface-modified cellulose fibers, and more preferably surface-modified nano-cellulose fibers. The surface-modified cellulose fibers may be included to modify the highly crystalline PLA linear crystal structure. Specifically, it may be included to improve melt flowability by inducing a change in shear viscosity by inducing a change in chain entanglement of the PLA polymer.

In addition, the cellulose fiber has a high aspect ratio, and in order to prepare the composite material of the present invention in the form of a fiber or nonwoven fabric, it serves as a support in the biodegradable resin in the melt spinning or stretching process, thereby improving the stiffness of the resin composition. can represent

The cellulose fibers are surface-modified with a silane compound. As will be described later, the nano-cellulose fibers may be included in a form bonded to a surface using a silane compound.

The silane compound is bonded to the surface of the cellulose fibers and can be uniformly distributed when mixed with a biodegradable polymer. Cellulose fibers that are not surface-modified are not uniformly mixed due to agglomeration between the cellulose fibers when mixed with the biodegradable polymer, but surface-modified cellulose fibers can be uniformly mixed.

In addition, the surface-modified cellulose fiber increases the bonding force with the PLA polymer, induces a change in chain entanglement of the PLA polymer as described above, induces a change in shear viscosity, and improves melt flowability, and is a biodegradable resin. By performing the role of a support within, it can exhibit the effect of improving the stiffness of the resin composition.

The viscosity modifier is a peroxide, and the peroxide is tert-butyl peroxide (2.5-Dimethyl 2.5-Di(Tert-butylperoxy)hexane, DTBH), benzoyl peroxide, bisdicyclobenzoyl peroxide, dicmyl peroxide, and mixtures thereof It is selected from the group consisting of, preferably tert-butyl peroxide (2.5-Dimethyl 2.5-Di (Tert-butylperoxy) hexane, DTBPH), but all viscosity modifiers for increasing the thermal stability and viscosity of the composite material can be used. there is.

The viscosity modifier is generally included to increase the viscosity of the thermoplastic resin, and at this time, it must be included in excess to increase the viscosity of the thermoplastic resin. However, when mixed with a biodegradable polymer resin and used in an excessive amount, thermal stability may be deteriorated and physical properties may be deteriorated, so it is preferable to mix and use within the scope of the present invention.

The viscosity modifier may be included in the form of a master batch rather than being mixed alone. The master batch may include 90% by weight of Ramdom PP and 10% by weight of the viscosity modifier.

The acidic catalyst is hydroxyaluminum bis(2,2-methylene-bis(4,6-di-tert-butylphenyl) phosphate (Hydroxyaluminum bis(2,2-methylene-bis(4,6-di-tert-butylphenyl) )phosphate)), but any acidic catalyst that can be used for viscosity modification of biodegradable polymers can be used without limitation.

The acidic catalyst reacts with the biodegradable polymer to induce a hydrolysis reaction of the biodegradable polymer, and the molecular weight of the biodegradable polymer may be reduced by the hydrolysis. As described above, when the molecular weight of the biodegradable polymer is reduced, the melt index (MI) can be increased, and thus, it is possible to manufacture meltblown fibers using the biodegradable polymer.

The acidic catalyst may also be included in the form of a master batch in the same way as the viscosity modifier. The master batch may include 90% by weight of Ramdom PP and 10% by weight of the acidic catalyst.

The composite material of the present invention includes a biodegradable polymer and cellulose fibers in a weight ratio of 19: 1 to 4: 1, and based on 100 parts by weight of the biodegradable polymer and cellulose fibers, the viscosity modifier is 0.0001 to 0.0010 parts by weight and acidic The catalyst may be included in 0.1 to 1.5 parts by weight, and preferably, based on 100 parts by weight of the biodegradable polymer and cellulose fiber, the viscosity modifier may be included in 0.0003 to 0.0007 parts by weight and 0.3 to 1.0 parts by weight of the acidic catalyst. The composite material included within the above range has a melt index (MI) of 250 or more at 250 ° C., preferably has a melt index (MI) of 400 or more at 250 ° C., and can be made into meltblown fibers by melt spinning, , can be made of meltblown nonwoven fabric, has excellent workability, and can exhibit high barrier properties and excellent physical properties.

Method for producing a composite material comprising a biodegradable polymer according to another embodiment of the present invention includes the steps of: 1) modifying cellulose fibers to prepare surface-modified cellulose fibers; 2) preparing a master batch by melting and mixing the biodegradable resin, the surface-modified cellulose fibers and the viscosity modifier of step 1) in a twin-screw extruder, and reaction-extruding; 3) preparing pellets for a composite material by melting and mixing the master batch, the biodegradable resin, and the acidic catalyst of step 2) in a twin screw extruder, and extruding the mixture; and 4) preparing a composite material by drying the composite material pellets.

Specifically, step 1) is a step of preparing surface-modified cellulose fibers by modifying cellulose fibers.

The cellulose fibers are nanocellulose fibers, and have an average diameter of 10 to 100 nm, an average length of 1 to 10 μm, and transmittance (wavelength 600 nm) of 30 to 35%.

The nanocellulose fibers are short fibers having a nanometer diameter and a short average length, and are easy to uniformly distribute in the biodegradable polymer resin, and as described above, the reactivity with the biodegradable polymer is improved by surface modification , By inducing a change in the chain entanglement of the PLA polymer, inducing a change in the shear viscosity, the melt flow can be improved, and the stiffness of the resin composition can be improved by serving as a support in the biodegradable resin. there is.

More specifically, in step 1), the solution in which the cellulose is mixed is stirred, a silane compound is added and stirred for 4 to 6 hours at a stirring speed of 650 to 850 rpm, and then at 95 to 115 ° C. at a stirring speed of 700 to 850 rpm. Stirring for 5 to 15 minutes to prepare surface-modified nano-cellulose fibers, preferably, in step 1), the cellulose-mixed solution is stirred, a silane compound is added, and the stirring speed is 700 to 800 rpm for 4 to 6 hours. After stirring, surface-modified nano-cellulose fibers may be prepared by stirring at 95 to 115° C. at a stirring speed of 790 to 830 rpm for 5 to 15 minutes.

The silane compound is prepared by mixing a silane compound and distilled water in a weight ratio of 1:5, mixing an organic acid, and stirring for 20 to 30 minutes at a stirring speed of 250 to 390 rmp. Preferably, the silane compound is It may be prepared by including a silane compound and distilled water in a weight ratio of 1:5, mixing acetic acid, and stirring for 20 to 30 minutes at a stirring speed of 300 to 340 rmp.

The silane compound is aminopropyltriethoxysilane, aminopropyltrimethoxysilane, amino-methoxysilane, phenylaminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-( -Aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropyltridimethoxysilane, γ-aminopropyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyldiethoxysilane, vinyltri ethoxysilane, vinyltrimethoxysilane, vinyltri(methoxyethoxy)silane, di-, tri- or tetraalkoxysilane, vinylmethoxysilane, vinyltrimethoxysilane, vinylepoxysilane, vinyltriepoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, chlorotrimethylsilane, trichloro Ethylsilane, trichloromethylsilane, trichlorophenylsilane, trichlorovinylsilane, mercaptopropyltriethoxysilane, trifluoropropyltrimethoxysilane, bis(trimethoxysilylpropyl)amine, bis(3-tri Ethoxysilylpropyl) tetrasulfide, bis(triethoxysilylpropyl)disulfide, (methacryloxy)propyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycy It is selected from doxypropylmethyldiethoxysilane, 3-glycidoxypropyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, and combinations thereof, preferably 3-glycidoxypropyldiethoxysilane. Although it is sidoxypropyltriethoxysilane, it is possible to prepare surface-modified nano-cellulose fibers by bonding with nano-cellulose fibers, induce changes in chain entanglement of PLA polymer, induce changes in shear viscosity, and improve melt flowability. Any silane compound capable of improving the stiffness of the resin composition by performing a support role in the biodegradable resin and exhibiting an effect of improving the stiffness of the resin composition may be used without limitation.

After preparing the surface-modified nano-cellulose fibers in step 1), the biodegradable resin, the surface-modified nano-cellulose fibers and viscosity modifier in step 1) were melt-mixed in a twin-screw extruder, and reaction extruded to obtain a master batch can be manufactured

When the surface-modified nano-cellulose fibers are directly mixed with the biodegradable polymer resin, the effect of mixing the surface-modified nano-cellulose fibers is not expressed. That is, in order to uniformly include the surface-modified nano-cellulose fibers throughout the composite material, it is not directly mixed with the biodegradable resin and used, but first, the biodegradable polymer, the nano-cellulose fibers, and the viscosity modifier are mixed and melt-mixed, The reaction is induced, and it is extruded to make a master batch.

In step 2), the surface-modified nanocellulose is first mixed with the biodegradable polymer to be uniformly distributed.

Thereafter, it is mixed with the biodegradable resin again in a step described later. As the surface-modified nano-cellulose fibers mixed in the master batch are melt-mixed in a twin-screw extruder with the biodegradable resin and the acidic catalyst in a uniformly mixed form with the biodegradable resin, they can be uniformly distributed.

The master batch containing the surface-modified nano-cellulose fibers, biodegradable resin, and acidic catalyst are put into a twin-screw extruder, melt-mixed, and reaction-extruded to prepare pellets for a composite material, and then dried to produce a composite material. .

A meltblown nonwoven fabric according to another embodiment of the present invention may include the composite material.

The composite material has a melt index (MI) of 250 or more at 250 ° C., preferably 400 or more, the molecular weight of the polymer contained in the composite material is small, the fluidity is excellent, and the processability is easy when manufactured into fibers, and the discharge amount This is a lot.

In addition, it has excellent thermal stability and can be provided as a nonwoven fabric having excellent stability even when stored for a long time.

The method of manufacturing the meltblown nonwoven fabric using the composite material is manufactured using a conventional manufacturing method, and is not limited to a special manufacturing method.

manufacturing example

Preparation of Surface Modified Nano Cellulose Fibers

While stirring the nanocellulose fibers having an average thickness of 10 to 100 nm, an average length of 1 to 10 μm, and a transmittance (wavelength 600 nm) of 33% at 15 to 25 ° C, the 3-glycidoxypropyltrimethoxysilane compound was added to the above The nano-cellulose fibers were mixed in 50 parts by weight compared to 100 parts by weight, and stirred at 750 rpm for 4 to 6 hours. Thereafter, the mixture was heated to 105° C. and stirred at 810 rpm for 10 minutes to prepare surface-modified nano-cellulose fibers.

The 3-glycidoxypropyltrimethoxysilane compound is prepared by mixing distilled water and 3-glycidoxypropyltrimethoxysilane in a weight ratio of 5:1, adding 0.2ml of acetic acid and stirring at 320 rpm for 20 to 30 minutes. manufactured.

Whether or not the surface modification of the nano-cellulose fibers was confirmed through SEM / EDS analysis, the analysis results are shown in Figures 4 and 5 and Table 1 below. Si element was detected on the surface of the nano-cellulose fibers, confirming that the nano-cellulose fibers were modified.

Spectrum 33 Element wt% Atomic % C 99.63 99.84 Si 0.37 0.16 Total: 100.00 100.00

Manufacture of composite materials

PLA was used as a biodegradable polymer, and the PLA, surface-modified nanocellulose fibers, and viscosity modifier DTBPH were melt-mixed in a twin-screw extruder, and reaction-extruded to prepare a master batch. At this time, the temperature of the twin-screw extruder was set to 80 to 190 ° C. from the hopper to the die.

The surface-modified nano-cellulose fibers were included in 6.6 parts by weight based on 100 parts by weight of PLA, and also included 6.6 parts by weight of a viscosity modifier.

The prepared master batch was put into a twin screw extruder together with PLA and acidic catalyst hydroxyaluminum bis(2,2-methylene-bis(4,6-di-tert-butylphenyl)phosphate, melt-mixed, and reacted extruded to obtain a composite Pellets for materials were prepared.

The pellets were then placed in a vacuum hopper and subjected to crystallization and dehumidification and drying processes to prepare a composite material.

The viscosity modifier was used as a master batch in which 90% by weight of Random PP and 10% by weight of DTBPH were mixed, and an acidic catalyst, 90% by weight of Random PP and hydroxyaluminum bis(2,2-methylene-bis(4,6- Di-tert-butylphenyl) phosphate was used as a master batch mixed with 10% by weight.

The PLA used two types of PLA L130 and PLA L105, PLA L130 has a melt index (MI) of 190 ° C. 11 g / 10 min, and PLA L105 has a melt index (MI) of 190 ° C. 36 g / 10 min.

Experimental Example 1

Melt index measurement

The melt index of the manufactured composite material was confirmed. The measurement of the melt index was performed at a constant temperature (190℃, 210℃, 190℃, 230℃, 250℃) and a constant load (2.16kg) by moving the melt through a prescribed orifice (2.09mm inner diameter, 8.0mm height) for 10 minutes. The weight of the extruded resin was measured.

The experimental results are shown in Table 2 below.

PLA130 PLA105 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Example 4 Example 2 Comparative Example 5 PLA-L130 100 - 100 100 100 91 - - - PLA-L105 - 100 - - - - 91 91 91 PEG - - 0.5 - - - - - - PPG - - - 0.5 - - - - - nano cellulose - - - - - 9 9 9 9 viscosity modifier - - - - 0.001 0.000315 0.000315 0.000315 0.000315 acid catalyst - - - - - 0.7 0.35 0.7 1.0 MI
(g/10min) 190℃ 11 36 13 12 13 18 37 48 60 210℃ 27 80 31 32 33 49 73 118 124 230℃ 55 156 72 69 68 105 178 298 340 250℃ 98 276 128 121 112 284 423 710 828

(Parts by weight, viscosity modifier and acidic catalyst were included based on 100 parts by weight of the total weight of PLA or PLA and nanocellulose.)

According to the above experimental results, PLA L130 and PLA L105 have low melt indices, making it difficult to melt spinning. In addition, it was confirmed that Comparative Examples 1 and 2 in which PEG or PPG were mixed with PLA did not show a melt index at a level capable of melt spinning, although some increase in melt index compared to the case where only the same PLA was used.

In addition, in the case of Examples 1 and 2, it was confirmed that a higher level of melt index was exhibited in the case of using PLA L105 compared to the case of using PLA L130.

In Comparative Example 5, an excessive amount of the acidic catalyst was used compared to Examples 1 and 2. Although the melt index increased as the content of the acidic catalyst increased, it was confirmed that the color of the resin turned yellow during the extrusion process.

Experimental Example 2

Molecular weight measurement result

Tosoh's EcoSEC HLC-8320 model was used, the detector was RI-detector, the developing solvent was HFIP (Hexafluoroisopropanol) and 0.01N NaTFA (trifluoroacetic acid Na salt), and the column was TSKgel guardcolumn SuperAW-H and 2 x TSKgelAWM-H (6.0 × 150 mm), and GPC analysis was performed using PMMA as a standard material.

The experimental results are shown in Table 3 below.

GPC Mn Mw Mz Mz/Mw Mw/Mn PLA-L130 96,328 168,327 278,066 1.652 1.747 PLA-L105 80,929 144,790 239,413 1.654 1.789 Comparative Example 4 90,286 163,507 279,713 1.711 1.811 Example 1 71,631 127,717 210,731 1.650 1.783

According to the measurement results, in Comparative Example 4 compared to PLA L130, Mn, Mw, and Mz were partially reduced, but did not show a large difference.

On the other hand, it can be seen that Example 1 shows lower values in Mn, Mw and Mz compared to PLA L105. As described above, the molecular weight measurement result shows a lower molecular weight than when only PLA is used, which is to indicate a high melt index as in the previous experiment.

Experimental Example 3

Physical property measurement

For the measurement of physical properties, a specimen was manufactured using a mold of KSM 527 1A (ISO 527-2, 1A) using an injection molding machine. At this time, the temperature is 170 ° C / 180 ° C / 190 ° C / 190 ° C in the case of a low-flow sample in the order from the hopper part to the nozzle, and 150 ° C / 160 ° C / 175 ° C / 175 ° C in the case of a high-flow sample, and the injection pressure is 1,800 kgf/cm ² .

Tensile force, elongation, and young's modulus were measured using the prepared specimens.

The method for measuring the physical properties was performed by testing the physical properties of plastics using Instrong equipment (UTM).

KSM 527 1A (ISO 527-2, 1A) standard was used, and ISO tensile specimens were measured for tensile strength, elongation at break and Young's modulus at a crosshead speed of 50 mm/min, and each sample was evaluated 5 times and the average value was used. .

PLA 130 PLA 105 Comparative Example 1 Comparative Example 2 Example 1 Example 2 Tensile (kgf/cm ² ) 752.4 729.8 772 774.0 745.4 722.1 Elongation (%) 4.4 4.2 3.4 3.1 2.7 2.8 Young's modulus (Mpa) 3437.3 3014.3 3231.1 3196.7 3283.4 3841.2

According to the above experimental results, it was confirmed that Example 1 and Example 2 exhibited a similar level of elongation and increased modulus, although the elongation decreased compared to the case of Comparative Example and PLA alone.

Experimental Example 4

Dispersibility review

In order to confirm the dispersibility according to the use of the surface-modified nanocellulose fibers, the dispersibility of the nanocellulose fibers was confirmed by measuring SEM pictures.

Experimental results are shown in Figures 1 to 3.

1 relates to nano-cellulose fibers included in Example 2 of the present invention, and it can be seen that agglomeration does not occur between nano-cellulose fibers and is evenly distributed.

In order to more clearly confirm the dispersibility according to the surface modification, the surface-modified nanocellulose fibers and the surface-modified nanocellulose fibers were mixed with PLA L105, and the dispersibility was evaluated.

Experimental results are shown in FIGS. 2 and 3 .

2 is a nano-cellulose fiber that is not surface-modified, and it can be seen that agglomeration occurs. On the other hand, Figure 3 is a surface-modified nano-cellulose fiber, it can be seen that it is uniformly dispersed in the same manner as in Example 2 above.

Experimental Example 5

Thermal stability evaluation

Melting temperature and decomposition temperature were measured to evaluate thermal stability.

Melting temperature was measured by the DSC measurement method, using a differential scanning calorimeter (DSC) from TA Instruments under a nitrogen stream. As the temperature condition, the heat history was removed at 30 to 250 degrees and 10 degrees/min as the first heating. After that, it was rapidly cooled from 250 ° C to -70 ° C, and the cooling rate at this time was -10 ° C / min. Thereafter, the second heating was measured at a heating rate of 10 °C/min in the range of -70 °C to 250 °C. The melting temperature (Tm) was confirmed during the second heating.

The decomposition temperature was measured by TGA, and a thermogravimetric analyzer (TGA) from TA Instruments was used. The heating rate was 20 ° C / min in a nitrogen atmosphere as an analysis condition, and the measured temperature range was 30 ° C to 900 ° C. As a result of the measurement, Td, 　Td　onset, 　T5%, and 　T50% were confirmed.

DSC TGA analysis results Tm Tdmax Tdonset Td 5% Td 50% PLA-L130 173 348 330 320 344 PLA-L105 171 346 333 324 343 Example 1 167 334 322 313 335 Example 2 165 345 323 307 341

(Unit ℃) As a result of the above experiment, it was confirmed that Tm exhibited a low temperature due to the decrease in molecular weight, and it was confirmed that there was no significant difference in decomposition temperature.

Experimental Example 6

Manufacture of meltblown nonwoven fabric

Melt-blown nonwoven fabric was prepared by melt-spinning the following resin by the melt-blown method. As for the spinning conditions, workability and spinnability were confirmed while changing gear pumps of 20, 25, and 30 RPM at a die temperature of 265 ° C and a hot air temperature of 275 ° C. The basis weight of the meltblown nonwoven fabric was adjusted to 20 to 40 gsm.

The evaluation criteria are as follows.

Workability was checked for defects (fly, shot) during spinning.

Criteria

Phase: Fly, shot and no increase in pack pressure during production

Medium: Fly and shot partially occur, and pack pressure is rather high during production

Bottom: The spinning itself is difficult due to the increase in pack pressure

Fly: A phenomenon in which fibers are cut and blown away (occurs from raw materials with too high melt flow, wide molecular weight distribution, and low physical properties)

shot: Check for defects in lumps caused by polymers sticking together (occurs in the case of raw materials with low melt flow)

Spinning stability was determined by the number of thread breaks per unit time (hr) per unit width (m).

Criteria

Top: 2 or less;

Medium: 4 or less

Bottom: 5 or more

The experimental results are shown in Table 7 below.

division PLA 105 Comparative Example 1 Comparative Example 4 Example 1 Example 2 Comparative Example 5 Workability middle
(Shot occurs) under
(Cannot work due to increased pack pressure) middle
(Shot occurs) award award award radial stability under unconfirmed under award award award

As a result of the above experiment, when the meltblown nonwoven fabric was produced with only PLA, workability was medium and spinning stability was evaluated to be low. On the other hand, in Examples 1 and 2, it was confirmed that it was possible to manufacture a meltblown nonwoven fabric using PLA, a biodegradable polymer, with both workability and spinning stability. However, in the case of Comparative Example 5, workability and spinnability were good, but it was confirmed that the color of the nonwoven fabric turned yellow during the production of the meltblown nonwoven fabric.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also made according to the present invention. falls within the scope of the rights of

Claims (11)

biodegradable polymer resin;
cellulosic fibers;
viscosity modifier; and
contains an acidic catalyst;
The cellulose fibers are surface-modified cellulose fibers
A composite material containing a biodegradable polymer. According to claim 1,
The biodegradable resin is polylactic acid, poly(butylene succinate), polyhydroxyalkanoate, polybutylene adipate-co-terephtalate ) And selected from the group consisting of mixtures thereof
A composite material containing a biodegradable polymer. According to claim 1,
The biodegradable resin has a melt index (MI) of 6 g / 10 min to 60 g / 10 min at 190 ° C.
A composite material containing a biodegradable polymer. According to claim 1,
The cellulose fiber is surface-modified with a silane compound
A composite material containing a biodegradable polymer. According to claim 1,
The viscosity modifier is a peroxide,
The peroxide is selected from the group consisting of tert-butyl peroxide (2.5-Dimethyl 2.5-Di(Tert-butylperoxy)hexane, DTBPH), benzoyl peroxide, bisdicyclobenzoyl peroxide, dicmyl peroxide, and mixtures thereof
A composite material containing a biodegradable polymer. According to claim 1,
The acidic catalyst is hydroxyaluminum bis(2,2-methylene-bis(4,6-di-tert-butylphenyl) phosphate (Hydroxyaluminum bis(2,2-methylene-bis(4,6-di-tert-butylphenyl) )phosphate)) phosphorus
A composite material containing a biodegradable polymer. 1) modifying cellulose fibers to prepare surface-modified cellulose fibers;
2) preparing a master batch by melting and mixing the biodegradable resin, the surface-modified cellulose fibers and the viscosity modifier of step 1) in a twin-screw extruder, and reaction-extruding;
3) preparing pellets for a composite material by melting and mixing the master batch, the biodegradable resin, and the acidic catalyst of step 2) in a twin screw extruder, and extruding the mixture; and
4) comprising the step of manufacturing a composite material by drying the pellet for the composite material
A method for producing a composite material containing a biodegradable polymer. According to claim 7,
In step 1), the solution in which the cellulose is mixed is stirred, the silane compound is added, and stirred for 4 to 6 hours at a stirring speed of 650 to 850 rpm, and then at 95 to 115 ° C. at a stirring speed of 700 to 850 rpm for 5 to 15 minutes. While stirring to prepare surface-modified nano-cellulose fibers
A method for producing a composite material containing a biodegradable polymer. According to claim 8,
The silane compound is prepared by mixing a silane compound and distilled water in a weight ratio of 1:5, mixing an organic acid, and stirring for 20 to 30 minutes at a stirring speed of 250 to 390 rmp
A method for producing a composite material containing a biodegradable polymer. According to claim 8,
The silane compound is aminopropyltriethoxysilane, aminopropyltrimethoxysilane, amino-methoxysilane, phenylaminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-aminopropyltridimethoxysilane, γ-aminopropyldimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyldiethoxy Silane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltri(methoxyethoxy)silane, di-, tri- or tetraalkoxysilane, vinylmethoxysilane, vinyltrimethoxysilane, vinylepoxysilane, vinyl Triepoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, chlorotrimethyl Silane, trichloroethylsilane, trichloromethylsilane, trichlorophenylsilane, trichlorovinylsilane, mercaptopropyltriethoxysilane, trifluoropropyltrimethoxysilane, bis(trimethoxysilylpropyl)amine, bis (3-triethoxysilylpropyl)tetrasulfide, bis(triethoxysilylpropyl)disulfide, (methacryloxy)propyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, selected from 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, and combinations thereof
A method for producing a composite material containing a biodegradable polymer. Comprising the composite material according to claim 1
Meltblown nonwoven fabric.