KR101231960B1 - Environmenntally friendly nonweaven fiber having a polylactic acid and the manufacturing method thereof - Google Patents

Abstract

The present invention relates to a method for producing an eco-friendly spunbond nonwoven fabric according to the complex spinning of polylactic acid and a nonwoven fabric produced by the present invention, wherein the environmentally-friendly nonwoven fabric through the composite spinning of the polylactic acid of the present invention is a polylactic acid and polypropylene blend In the nonwoven fabric produced by spinning, the nonwoven fabric is 10 to 25% by weight of polylactic acid, 65 to 89% by weight of polypropylene, and 1 to 1 by weight of the total weight of the polymer mixture for blending Sheath core formed of 10 wt% polypropylene / polylactic acid blend resin to form a core layer of 50 to 80 wt% of the total weight and 20 to 50 wt% of plant-derived polyethylene resin as a sheath layer. core) filament is characterized in that the.
The eco-friendly spunbond nonwoven fabric and the method of manufacturing the same through the composite spinning of the polylactic acid of the present invention configured as described above to produce a nonwoven fabric by blending polypropylene and polylactic acid as a core layer and composite spinning of polyethylene as a sheath layer, The above problems have been solved by providing an eco-friendly spanbonded nonwoven fabric which has excellent productivity and mechanical properties while dramatically reducing carbon dioxide emissions.

Description

Environmentally friendly spunbond nonwoven fabric and its manufacturing method through the complex spinning of polylactic acid {environmenntally friendly nonweaven fiber having a polylactic acid and the manufacturing method

The present invention relates to a method for producing an eco-friendly spunbond nonwoven fabric according to the complex spinning of polylactic acid, and to a nonwoven fabric produced by the present invention. The present invention relates to an eco-friendly spunbond nonwoven fabric and a method for producing the same, which are easy to reduce carbon emissions by forming a nonwoven fabric, and a complex spinning of polylactic acid, which maintains softness and strength by spinning plant-derived polystyrene on the sheath layer. .

Conventional nonwoven fabrics for sanitary material backsheets such as infant diapers, adult incontinence diapers, sanitary napkins, etc. are made of polyethylene film as the outermost layer for thinning and softening the appearance of the hygiene material, and melt-blown microfiber with a composite spun multilayer structure span bond Multilayered nonwoven fabric etc. in which the nonwoven fabric was formed inside are used.

On the other hand, however, due to environmental pollution problems caused by waste polymers such as the nonwoven fabrics and soaring petroleum prices, which increase exponentially with the development of technology and the improvement of the quality of life, the environmental burden is small and the recovery from biomass is obtained. This possible plant-derived polymer material is attracting attention. In particular, in recent years, biodegradable polymers that can be naturally decomposed in soil or landfills are in the spotlight as environmental pollution becomes severe.

Among these polymers, aliphatic polyester polymers are the most researched as biodegradable polymers because of their excellent processability and easy control of their decomposition properties. Among them, polylactic acid (PLA) has a market of 100,000 tons worldwide. And the scope of application is expanding to the field where general plastics such as food packaging materials, containers, and electronics cases were used.

In recent years, research has been conducted on blending polylactic acid and polypropylene. However, when the polylactic acid is blended with polypropylene, the amount of general purpose resin derived from petroleum raw materials can be suppressed. The amount of raw materials used can be suppressed, and the generation of carbon dioxide gas at the time of disposal and the heat of combustion can be lowered, which has attracted much attention as a method for reducing the environmental burden. In particular, polypropylene, the most widely used disposable hygiene product, consumes 3,200kg of carbon dioxide to burn 1 ton of polypropylene, whereas polylactic acid is 1,830kg, which is only 57% of polypropylene. It is in a very advantageous position.

However, in spite of the above advantageous aspects, when blending the polylactic acid and polypropylene, there is a problem in that the dispersibility of the polylactic acid and polypropylene is not sufficient to improve the heat resistance or mechanical properties, and thus this problem is solved. Some solutions have been proposed to solve the problem. For example, as a blend of polylactic acid and a thermoplastic resin other than polylactic acid, the polylactic acid and polymethyl methacrylate are disclosed in Japanese Patent Laid-Open No. 2005-171204. Although a blend with (polymethylmethacrylate) is disclosed, the patented method has limitations in improving compatibility with polylactic acid and incompatible polypropylene.

In addition, in the case of blending and spinning polylactic acid and general-purpose resin, problems such as severe pressure rise of the die and thread breaking occurred due to the manufacturing process, which could not be practically used, even though the compatibility between polylactic acid and general-purpose resin was good. If the spinning manufacturing process is not supported, it means that nonwovens cannot be produced.

Meanwhile, in the case of the polypropylene / polyethylene nonwoven fabric which is conventionally used as a nonwoven fabric for sanitary backsheets such as infant diapers and adult incontinence diapers, nonwoven fabrics are manufactured using only petroleum-derived polyolefin-based resins to reduce carbon emissions. There was a limit in the manufacturing process.

Patent Document 1: Japanese Unexamined Patent Publication No. 2005-171204

Accordingly, the present invention has been made in view of the above-mentioned conventional technical problems. The main object of the present invention is a plant-derived polypropylene / polylactic acid blend having excellent compatibility between polylactic acid and polypropylene as a core layer. Since the non-woven fabric is produced by the composite spinning of polyethylene into the sheath layer, it is to provide an eco-friendly spunbond nonwoven fabric through the composite spinning of polylactic acid, while reducing carbon dioxide emissions while having excellent biodegradability and mechanical properties.

Another object of the present invention is to provide a method for producing a nonwoven fabric having the above characteristics more easily.

The present invention may also be aimed at achieving, in addition to the above-mentioned specific objects, other objects which can be easily derived by those skilled in the art from this and the overall description of the present specification.

Eco-friendly spanbond nonwoven fabric through the composite spinning of the polylactic acid of the present invention for achieving the above object;

In nonwoven fabrics made through polylactic acid and polypropylene blend spinning,

The nonwoven fabric is a polypropylene / polypropylene / consisting of 10 to 25% by weight of the total weight of the polymer mixture for blending, 65 to 89% by weight of polypropylene, and 1 to 10% by weight of the dispersant It is composed of a sheath-core filament formed of a polylactic acid blend resin to form a core layer of 50 to 80% by weight of the total weight and 20 to 50% by weight of plant-derived polyethylene resin as an outer layer. It features.

According to another configuration of the present invention, the nonwoven fabric may be composed of multiple layers in the form of a spanbond nonwoven fabric / meltblown nonwoven fabric / spanbond nonwoven fabric. Here, the spanbonded nonwoven fabric layer forming the outer layer may be composed of one or more layers, and the inner meltblown layer may also be composed of one or more layers, and the number of layers to be formed is not limited.

According to another configuration of the present invention, the dispersant is characterized in that it comprises a hydrophilic portion that is miscible with the polylactic acid polymer and a hydrophobic portion that is miscible with the polypropylene polymer.

According to another configuration of the present invention, the component of the dispersant is characterized in that the styrene- ethylene- butylene- styrene block copolymer component.

According to another configuration of the present invention, the plant-derived polyethylene resin is characterized in that the polyethylene polymerized with ethanol obtained from sugar cane.

Method for producing an environmentally friendly spanbond nonwoven fabric through the composite spinning of the polylactic acid of the present invention for achieving the above another object;

In the process for producing a nonwoven fabric by polylactic acid and polypropylene blend spinning,

The preparation method comprises 10 to 25% by weight of polylactic acid, 65 to 89% by weight of polypropylene, and 1 to 10% by weight of the dispersant in the total weight of the polymer mixture for blending. Dispersing the polylactic acid and the polypropylene as a phase by uniformly dry mixing the polylactic acid in the polypropylene resin through a dispersant to form a thermoplastic composition dry mixture;

Advantageously stirring, stirring or otherwise blending the thermoplastic composition dry mixture to effectively and uniformly mix the polylactic acid polymer, polypropylene polymer and dispersant to form a homogeneous dry mixture; And

By varying the polypropylene / polylactic acid dry mixture and the extruder for melting the plant-derived polyethylene, a distribution plate for inducing each molten polymer is present on the nozzle so that the polypropylene / polylactic acid molten polymer is formed inside the filament. The plant-derived polyethylene is characterized in that consisting of the step of forming a spunbond nonwoven fabric by forming the web by spinning the filament in the form of a sheath-core filament to the outside.

The eco-friendly spunbond nonwoven fabric and the manufacturing method thereof through the composite spinning of the polylactic acid of the present invention configured as described above to produce a nonwoven fabric by blending polypropylene and polylactic acid as a core layer and composite spinning of plant-derived polyethylene as a sheath layer Therefore, to solve the above problems by providing an eco-friendly spunbond nonwoven fabric with excellent productivity and mechanical properties while significantly reducing carbon dioxide emissions.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail by preferable embodiment.

Prior to describing the present invention in detail, the polylactic acid is generally defined by the polymerization of lactic acid or lactide, and is thus used in the present invention, as defined above for the polylactic acid used throughout the present specification. The term "polylactic acid" is intended to denote a polymer prepared by the polymerization of lactic acid or lactide. The lactic acid may be polymerized using any known polymerization method such as polycondensation or ring-opening polymerization. In the polycondensation process, for example L-lactic acid, D-lactic acid or mixtures thereof are applied directly to dehydration-polycondensation. In the ring-opening polymerization process, lactide, a cyclic dimer of lactic acid, is subjected to polymerization with the aid of polymerization regulators and catalysts. Lactides may include L-lactide, D-lactide and DL-lactide (also called meso-lactide, condensates of L-lactic acid and D-lactic acid). Each such lactide (ie, L-lactide, D-lactide and DL-lactide) is a dimer. That is, they consist of two lactic acid units. Because of its chiral center, lactic acid has two different stereochemical isomers, namely the R isomer and the S isomer shape. D-lactide comprises two R isomers, L-lactide comprises two S isomers, and meso-lactide includes the R and S isomers. Different isomers can be mixed and polymerized if necessary to obtain polylactic acid having any desired composition and crystallinity as described in more detail below. In addition, small amounts of chain extenders (eg diisocyanate compounds, epoxy compounds or acid anhydrides described below) may be used to increase the molecular weight of polylactic acid. Suitably, the weight average molecular weight of the polylactic acid is from about 60,000 to about 1,000,000.

Suitable polylactic acid polymers that can be used in the present invention include, but are not limited to, one specific example commercially under the name Natureworks (Natureworks®) of Minneapolis, Minn. Available. Other suitable polylactic acid polymers are commercially available from BIOMER ™ L9000 or Mitsui Chemical (LACEA ™) from Biomer, Inc., Cryling, Germany. It is possible. Still other suitable polylactic acids are described in US Pat. Nos. 4,797,468; No. 5,470,944; 5,770,682; No. 5,821,327; 5,880,254; 5,880,254; And 6,326,458 can be used.

In addition, the melt flow index of the polylactic acid can be forced through an extrusion flow meter orifice (0.0825 inches in diameter) when applied to a load of 2160 g in 10 minutes at any temperature (eg 210 ° C.), ASTM test method D1238-. The weight (g) of the polymer measured according to E is shown. Polylactic acid also typically has a melting point of about 100 ° C. to about 240 ° C., in some embodiments from about 120 ° C. to about 220 ° C., and in some embodiments from about 140 ° C. to about 200 ° C. These low melting polylactic acids are useful in that they biodegrade at high speed. The glass transition temperature (“Tg”) of polylactic acid is also relatively low to improve the solubility and processability of the polymer. For example, the Tg may be about 80 ° C. or less, in some embodiments about 70 ° C. or less, and in some embodiments about 65 ° C. or less. As discussed in more detail below, both the melting point and glass transition temperature can be determined using a differential scanning calorimeter (“DSC”) in accordance with ASTM D-3417.

According to the present invention, a nonwoven fabric prepared by forming a web by a cis-core type filament having a polypropylene / polylactic acid blend as a core layer and a plant-derived polyethylene as a cis layer is at least one or more spunbond nonwoven layers as necessary. And / or a polylactic acid meltblown nonwoven layer or a polypropylene meltblown nonwoven layer is additionally laminated. At this time, according to a preferred embodiment of the present invention, the polypropylene / polylactic acid blend contains 1 to 10% by weight of a dispersant which is a styrene-ethylene-butylene-styrene block copolymer component in polypropylene and polylactic acid. It is mixed with addition.

According to a preferred embodiment of the present invention, in the method for producing the nonwoven fabric of the present invention, the weight of the polylactic acid in the total weight of the polymer mixture for blending is 10 to 25% by weight, the weight of the polypropylene is 65 to 89% by weight, dispersant The weight of the composition comprises 1 to 10% by weight of the polylactic acid and the polypropylene as a substantially continuous phase by uniformly dry mixing the polylactic acid in the polypropylene resin through a dispersant to disperse to form a thermoplastic composition dry mixture, and the thermoplastic composition Advantageously stirring, stirring or otherwise blending the dry mixture to effectively and uniformly mix the polylactic acid polymer, the polypropylene polymer and the dispersant to form a homogeneous dry mixture, and the polypropylene / polylactic acid On dry mixtures and plant-derived poly Different extruders for melting the lens have a distribution plate on each nozzle to induce each molten polymer so that the polypropylene / polylactic acid molten polymer is formed inside the filament and the plant-derived polyethylene is formed outside. Spinning the filament in the form of a sheath-core to form a web and thermocompressing to form a nonwoven fabric.

According to a preferred embodiment of the present invention, the web integrated according to the present invention as described above is thermally bonded to impart mechanical properties and morphological stability. At this time, the bonding area is not limited, but the calender roll is configured on the one side of the emboss roll having an adhesive area of 10 to 20% by weight, and the other side is composed of a roll having a smooth surface. Multi-layer integrated webs can be sheeted through the rolls. In this case, the temperature of the emboss roll and the smooth roll is preferably 120 to 150 ° C, more preferably 130 to 140 ° C.

The following examples and comparative examples are intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples. Various properties and physical properties of the nonwoven fabrics prepared according to the following Examples and Comparative Examples were measured and evaluated by the following method.

(1) Weight: EDANA 40.3-90

(2) Tensile strength and Elongation: EDANA 20.2 -89

(3) Bending Length: EDANA 50.5-99

Examples and Comparative Examples

The fibers were prepared using the following polylactic acid, polypropylene, dispersant and plant derived polyethylene. Polylactic acid polymer (PLA) was obtained from Natureworks, Minneapolis, Minnesota, USA, with a melt flow index (MI: Melt Index) of 15-30 g / 10 min. The polypropylene polymer (PP) obtained the trade name SFR-171H from Honam Petrochemical, had a melt flow index (MI: Melt Index) of 35 g / 10 min, and had a melting temperature of about 160 ° C. The dispersing agent was obtained from JSR Corporation of Tsukiji, Japan, and used the trade name DYNARON 8630P. Plant-derived polyethylene was used under the trade name SHA7260 manufactured by Brasskem of Triunposi, South Rio Grande, Brazil, and supplied by Toyota tsusho.

Example 1

10% by weight of polylactic acid, 3% by weight of dispersant, and 87% by weight of polypropylene resin were melt-spun into the core layer by 50% of the total weight. The plant-derived polyethylene was melt-spun by adding 50% of the total weight to the sheath layer. Fiber to form and stretched on a porous conveyor belt to prepare a polylactic acid / polypropylene / polyethylene nonwoven fabric having a basis weight of 20gsm and measured in the physical properties are shown in Table 1.

Example 2

A nonwoven fabric was prepared in the same manner as in Example 1 except that polylactic acid / polypropylene blend resin was added to the core layer at 60% by weight of the total weight and 40% by weight of the plant-derived polyethylene was added to the sheath layer. Physical properties were measured and listed in Table 1.

Comparative Example 1

A nonwoven fabric was prepared in the same manner as in Example 1, except that 30 wt% of polylactic acid, 5 wt% of a dispersant, and 65 wt% of a polypropylene resin were prepared.

Comparative Example 2

A nonwoven fabric was prepared in the same manner as in Example 1 except that 50 wt% of the polypropylene resin was added to the core layer and 50 wt% of the polyethylene resin was added to the sheath layer. It described in 1.

Claims (7)

In nonwoven fabrics made through polylactic acid and polypropylene blend spinning,
The nonwoven fabric is polypropylene comprising 10 to 25% by weight of polylactic acid, 65 to 89% by weight of polypropylene, and 1 to 10% by weight of the dispersant. It is composed of a sheath-core filament formed of a polylactic acid blend resin to form a core layer of 50 to 80% by weight of the total weight and 20 to 50% by weight of plant-derived polyethylene resin as an outer layer. Eco-friendly spunbond nonwoven fabric with polylactic acid composite spinning.
The method of claim 1, wherein the nonwoven fabric is an eco-friendly spunbond nonwoven fabric through a composite spinning of polylactic acid, characterized in that composed of a multi-layer of a spunbond non-woven fabric, melt blown nonwoven fabric and a spanbond nonwoven fabric.
The method of claim 1, wherein the dispersing agent is an environmentally friendly spunbond nonwoven fabric through a composite spinning of polylactic acid, characterized in that it comprises a hydrophilic portion that is miscible with the polylactic acid polymer and a hydrophobic portion that is miscible with the polypropylene polymer.
4. The eco-friendly spunbond nonwoven fabric according to any one of claims 1 to 3, wherein the component of the dispersant is a styrene-ethylene-butylene-styrene block copolymer component. .
The method of claim 1, wherein the component of the plant-derived polyethylene resin is an eco-friendly spunbond nonwoven fabric through the complex spinning of polylactic acid, characterized in that the polyethylene obtained by polymerizing ethanol obtained from sugar cane.
delete In the process for producing a nonwoven fabric by polylactic acid and polypropylene blend spinning,
The production method is a polylactic acid in the total weight of the polymer mixture for blending is 10 to 25% by weight, the weight of polypropylene is 65 to 89% by weight, the weight of the dispersant is composed of 1 to 10% by weight of the continuous phase Forming a thermoplastic composition dry mixture by dispersing polylactic acid and polypropylene as uniformly dry mixed polylactic acid in the polypropylene resin through a dispersant;
Agitating or stirring the thermoplastic composition dry mixture to effectively and uniformly mix the polylactic acid polymer, the polypropylene polymer and the dispersant to form a homogeneous dry mixture; And
By varying the extruders for melting the dry mixture and the plant-derived polyethylene formed in the above step, a distribution plate for inducing each molten polymer is present on the nozzle so that the polypropylene and the polylactic acid molten polymer are in the filament, Plant-derived polyethylene is made of a step of forming a web by spinning the filament in the form of a cis-core to the outside to form a non-woven fabric by thermocompression manufacturing of eco-friendly spunbond nonwoven fabric through a composite spinning of polylactic acid Way.