KR20200126749A - Biodegradable Flame Retardant Heat-bonding Composite Binder Fiber - Google Patents

Abstract

The present invention relates to a biodegradable flame-retardant heat-bonding composite binder fiber comprising a sheath part and a core part, which simultaneously provides biodegradable flame-retardant properties. According to the present invention, the core part is made of a general polyester resin and the sheath part is made of a low-melting point polyester resin comprising an acid component formed of terephthalic acid or an ester-forming derivative ester thereof and a diol component formed of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol. A biodegradable agent is included in the sheath part and the core part and is made of at least one from aliphatic esters, aromatic esters, and polylactide. 0.3 to 0.5 wt% of a phosphorus flame retardant is added with respect to the composite fiber during polymerization of the sheath part and the core part and a content ratio of the phosphorus flame retardant of the sheath part and the core part is 1 : 3 to 3 : 1.

Description

Biodegradable Flame Retardant Heat-bonding Composite Binder Fiber}

The present invention relates to a biodegradable flame-retardant heat-adhesive composite binder fiber. Specifically, the heat-adhesive composite binder fiber formed of two types of resins has biodegradability and flame retardancy.

Synthetic fibers widely used until now include polyester, polyolefin, and polyamide fibers. These fibers not only have high strength and high elasticity, but also can be manufactured by melt spinning, so they have the advantage of imparting new properties to fibers through changes in cross-sectional shape during spinning.

Synthetic fibers as described above cannot be buried because they are non-degradable materials that do not decompose naturally, and are often processed by incineration, but when such synthetic fibers are incinerated, many harmful substances are released and harmful gases are generated to destroy the natural environment. In this regard, regulatory measures have been implemented or are in the stage of introduction, and many countries legally mandate the use of these environmentally degradable polymers.

Therefore, in recent years, as the problem of environmental pollution caused by waste synthetic fibers has emerged as a major social problem, studies on biodegradable polymer resins capable of completely degrading have been actively conducted, and a lot of interest has been aroused worldwide. In particular, as the limitations of the use of landfills and the problem of recycling have emerged seriously, the development of degradable resins that decompose by themselves when discarded after a certain period of use is being actively developed.

As a result of active research on biodegradable polymers, biodegradable polymers such as starch-based polymer, cellulose acetate, polyhydroxy butyrate, polylactide, polycaprolactone, and polybutylene succinate have been commercialized and marketed, but biodegradable. Since the physical properties that can produce films or fibers have not been secured yet, polyesters are being manufactured only for injection molding products.

Synthetic polymers used for biodegradability include aliphatic polyester (AP) and polyglycolic acid (PGA) represented by poly carprolacton (PCL) and polylactic acid (PLA). And they have relatively excellent physical properties.

Among them, aliphatic polyester polymers (PLA, PCL, PBS / PBSA / PBAT, etc.) are the most studied because of their excellent processability and easy control of decomposition properties. In particular, polylactic acid (PLA) is 15 It is forming a market of 10,000 tons, and its application range is expanding to areas where general plastics such as food packaging materials and containers, and electronic product cases have been used. Until now, the main uses of PLA resin are disposable products, such as food containers, wraps, films, etc., using the biodegradable properties of PLA. PLA is currently being produced by Natureworks of the United States and Toyota of Japan.

In Korean Patent Laid-Open No. 1996-3672, an antimicrobial non-porous inorganic ceramic containing a silver compound and a zirconium compound and a far-infrared radiation oxide ceramic are added to a polypropylene resin, and a batch of polypropylene masters and a polypropylene resin for general non-woven fabrics are mixed and melt-spun. A method for producing a polypropylene long fiber nonwoven fabric having excellent antibacterial deodorant and spinnability, characterized by forming a web and thermally bonding, has been proposed.

However, the inorganic ceramic applied in the above patent is difficult to control the dispersibility of the particles, and when fine denier spinning of 2 denier or less, there is a problem such as trimming due to an increase in pressure due to the fine particles.

In addition, in Korean Patent Invention No. 536004, a processing bath liquid obtained by mixing 10 to 20 parts by weight of chitosan, 2.0 to 4.0 parts by weight of chitosan reaction catalyst, 0.5 to 1 part by weight of an absorbent (Pepol), and 75 to 85 parts by weight of loess holding water is used as polyamide or A method of producing a spunbond nonwoven fabric having a combination function of far-infrared radiation and antibacterial deodorization, characterized by coating and drying a polyolefin-based long fiber spunbond nonwoven fabric by a kiss roll and spray dispersion method, has been proposed.

When the kiss roll and spray are applied, it may be difficult to uniformly disperse the contained material, and the above-described complex functional effect may be expressed, but there is a disadvantage in that thermal stability or adhesion may be deteriorated.

Therefore, it is urgent to develop synthetic fibers capable of biodegradation while maintaining the intrinsic physical properties of heat-adhesive binder fibers.

The present invention was developed to solve the problems of the prior art as described above, and it is an object of the present invention to provide a flame-retardant heat-adhesive composite binder fiber having biodegradability by using two types of synthetic resins and including a biodegradable agent in the two types of synthetic resins. To do.

In addition, the present invention aims to provide a flame-retardant heat-adhesive composite binder fiber by adding a phosphorus-based flame retardant to the sheath part in the polymerization process to the sheath part by a composite spinning technology and adding a phosphor-based flame retardant in the polymerization process to the core part. do.

In order to solve the above problems, the present invention is a biodegradable heat-adhesive composite binder fiber formed of a sheath portion and a core portion, wherein the core portion is formed of a general polyester resin, and the sheath portion is formed of terephthalic acid or an ester-forming derivative thereof. It is formed of a low melting point polyester resin formed of an acidic component consisting of, and a diol component consisting of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol, and the sheath portion and A biodegradant is included in the core part, and the biodegradable agent is at least one of aliphatic ester-based, aromatic ester-based, and polylactide, and a phosphorus-based flame retardant in the polymerization reaction of the sheath part and the core part is 0.3 to 0.5% by weight compared to the composite fiber. And, it provides a biodegradable flame-retardant heat-adhesive composite binder fiber characterized in that the content ratio of the phosphorus-based flame retardant in the sheath portion to the core portion is 1:3 ~ 3:1.

In addition, the present invention comprises a biodegradable heat-adhesive composite binder fiber characterized in that the sheath part and the core part are in a weight ratio of 30:70 to 70:30, and the biodegradable agent is contained in 0.5 to 3.0% by weight, respectively, in the sheath part and the core part. to provide.

In addition, the present invention provides a biodegradable heat-adhesive flame-retardant composite binder fiber characterized in that the flame retardant comprises the following [Chemical Formula 1] as a phosphorus-based flame retardant.

[Formula 1]

Provided that R1, R2 are methyl, phenyl, halophenyl, alkyl, haloalkyl, or haloaryl

In addition, the present invention provides a biodegradable heat-adhesive composite binder fiber characterized in that the composite binder fiber is a core-sheath eccentric form or a core-sheath eccentric form or a side-by-side form.

In addition, the present invention provides a biodegradable heat-adhesive composite binder fiber characterized in that the 2-methyl-1,3-pentanediol of the low melting point polyester resin contains 0.01 to 5 mol% of the diol component.

In addition, the present invention provides a biodegradable heat-adhesive composite binder fiber characterized in that the 2-methyl-1,3-pentanediol of the low melting point polyester resin contains 0.05 to 2 mol% of the diol component.

In addition, the present invention provides a biodegradable heat-adhesive composite binder fiber characterized in that the difference between the melt viscosity of 220°C and the melt viscosity of 260°C is 600 poise or less in the low melting point polyester resin.

In addition, the present invention is characterized in that the general polyester resin of the core part has a melt viscosity of 2,000-2,500 poise at 280°C, and the polyester resin of the sheath part has a melt viscosity of 600-1,500 poise at 260°C. It provides a biodegradable heat-adhesive composite binder fiber.

In addition, the present invention provides a non-woven fabric comprising a biodegradable heat-adhesive composite binder fiber.

As described above, the heat-adhesive composite binder fiber having biodegradability and flame retardancy according to the present invention contains a biodegradable agent in a polyester resin and a low melting point copolymerized polyester resin, and also contains a phosphorus-based flame retardant in the polymerization process of the sheath and core resin. By adding it to a composite binder fiber, it has the effect of having biodegradability and flame retardancy at the same time.

Hereinafter, a preferred embodiment of the present invention will be described in detail. First, in describing the present invention, detailed descriptions of related known functions or configurations are omitted so as not to obscure the subject matter of the present invention.

The terms'about','substantially', etc. of the degree used in the present specification are used at or close to the numerical value when manufacturing and material tolerances specific to the stated meaning are presented, and are used in the sense of the present invention. To assist, accurate or absolute figures are used to prevent unfair use of the stated disclosure by unscrupulous infringers.

The present invention relates to a biodegradable heat-adhesive composite binder fiber formed of a sheath portion and a core portion, wherein the core portion is formed of a general polyester resin, and the sheath portion relates to a polyester fiber formed of a low-melting point polyester resin.

Here, a biodegradant is included in the cis portion and the core portion, and the biodegradable agent is at least one of an aliphatic ester-based, aromatic ester-based, and polylactide, and a phosphorus-based flame retardant may be added during the polymerization reaction of the cis portion and the core portion. I can.

In addition, the sheath part and the core part are in a weight ratio of 30:70 to 70:30, and the biodegradant is characterized in that 0.5 to 3.0% by weight of each of the sheath part and the core part is included.

Aliphatic polyester is known to be the most biodegradable polymer. In particular, it is said that polyesters derived from diacids of medium-sized monomers (C6-C12) are easily biodegraded by fungi such as Aspergillus niger or flavus or elastase. Structurally, an appropriate balance between hydrophobicity (simple polarity) and hydrophilicity (polarity) must be properly established for biodegradation to occur, and active sites for decomposition by enzymes must be provided in the molecular chain.

Considering the flexibility, the flexible aliphatic polyester is more prone to biodegradation than the rigid aromatic polyester. That is, as the stiffness increases, the susceptibility to hydrolysis by enzymes significantly decreases, so the biodegradability tends to decrease.

Polyester resin is hardly decomposed by fungi or enzymes, but the mixture with aliphatic polyester polylactic acid shows biodegradability.

Among the aromatic polyester resins, polylactone is also excellent in biodegradability. In addition, monosaccharides alginate and hyaluronic acid are also excellent in biodegradability.

Any general polyester resin forming the core portion may be used, but it would be preferable to use a polyethylene terephthalate (PET) resin made of terephthalic acid and ethylene glycol.

The low melting point polyester resin forming the cis portion is an acidic component composed of terephthalic acid or an ester-forming derivative thereof, and 2-methyl-1,3-propanediol (2-Methyl 1,3 Prorpanediol), 2-methyl-1, It is a polyester resin formed of a diol component consisting of 3-pentanediol (2-Methyl 1,3 Pentanediol) and ethylene glycol (EG).

The 2-methyl-1,3-propanediol used in the present invention facilitates rotation of the polymer main chain by bonding a methyl group to the second carbon, and acts as if it is an end of the polymer to widen the free space between the main chains, Increase the liquidity of This makes the polymer amorphous and has the same thermal properties as isophthalic acid. Due to the flexible molecular chains present in the polymer main chain, it improves the elasticity and thus improves the tear property when binding the nonwoven fabric.

That is, 2-methyl-1,3-propanediol contains a methyl group (-CH ₃ ) in the ethylene chain bonded to terephthalate as a side chain, thereby securing a space so that the main chain of the polymerized resin can rotate. It is possible to control the softening point (Ts) and/or the glass transition temperature (Tg) by inducing an increase and decrease in crystallinity of the resin. This may exhibit the same effect as in the case of using isophthalic acid (IPA) containing an asymmetric aromatic ring in order to lower the crystallinity of the conventional crystalline polyester resin.

The 2-methyl-1,3-pentanediol has a methyl group bonded to the second carbon like the 2-methyl-1,3-propanediol to facilitate rotation of the polymer main chain and impart low melting point properties to the polyester resin. It has the property of increasing the melt viscosity of the polyester resin with a longer molecular chain than 2-methyl-1,3-propanediol, and prevents the melt viscosity from rapidly decreasing at high temperatures.

The low melting point polyester resin of the present invention formed from the diol component as described above is 20 to 50 mol of the diol component of 2-methyl-1,3-propanediol in the low melting point polyester resin in order to improve the low melting point properties and adhesion. It would be desirable to contain %.

When the 2-methyl-1,3-pentanediol is contained in an amount of less than 0.01 mol% of the diol component, the effect of improving the melt viscosity is insignificant, and when it exceeds 5 mol%, the melt viscosity rapidly increases, thereby deteriorating the spinning processability. It will be preferable that 2-methyl-1,3-pentanediol contains 0.01 to 5 mol% of the diol component.

Most preferably, the 2-methyl-1,3-pentanediol contains 0.05-2 mol%.

As described above, the low melting point polyester resin of the sheath portion containing 2-methyl-1,3-pentanediol has a melt viscosity at a high temperature of 600 poise or less between the melt viscosity of 220°C and the melt viscosity of 260°C. Has a specificity that does not deteriorate rapidly.

The difference between the melt viscosity of 220° C. and the melt viscosity of 260° C. of the low melting point polyester resin is the lower, the more preferable it is, and it will be more preferably 500 poise or less.

The biodegradable heat-adhesive composite binder fiber of the present invention is a sheath-core composite fiber, and the general polyester resin of the core part has a melt viscosity of 2,000-2,500 poise at 280°C for spinning of the composite fiber in the spinning process, It will be preferable that the polyester resin of the sheath portion has a melt viscosity of 260° C. of 500 to 1,400 poise.

If the melt viscosity of the general polyester resin of the core portion is too high, the spinning processability may be deteriorated, resulting in a thread trimming phenomenon, and if the melt viscosity of the core portion is lower than that of the polyester resin of the sheath portion, the shape stability of the composite fiber may be reduced. In other words, it is preferable that the fiber cross section of the cis-core type may not be formed, and the general polyester resin of the core portion has a melt viscosity of 2,000 to 4,000 poise at 280°C.

The melt viscosity of the polyester resin of the sheath part is too high and the shape stability of the composite fiber may be reduced, and if the melt viscosity of the sheath part is too low, cross-sectional unevenness, howitzer, and trimming may occur. The resin preferably has a melt viscosity of 600-1,500 poise at 260°C, and more preferably 700 poise or more at 260°C.

The general polyester forming the core part is advantageous for improving the shape stability and spinning processability of the composite fiber in that the melt viscosity of the general polyester resin forming the core part and the melt viscosity of the polyester resin forming the sheath part are different within a certain range. It is preferable that the difference between the melt viscosity of the resin at 280° C. and the melt viscosity at 260° C. of the polyester resin forming the sheath is 700 to 2,500 poise, more preferably 1,000 to 2,000 poise.

As described above, the low melting point polyester resin of the present invention containing 2-methyl-1,3-propanediol and 2-methyl-1,3-pentanediol has a softening temperature of 100°C to 150°C, and a glass transition temperature It has excellent physical properties at 50°C to 90°C and an intrinsic viscosity of 0.50 ㎗/g or more.

The biodegradable heat-adhesive composite binder fiber of the present invention as described above can be thermally bonded at a low temperature in a range similar to the temperature applied to the existing binder fiber, as well as improved fairness, uniform physical properties of the fiber, and improved adhesion, When the glass transition temperature is over 60℃ and durability and shape stability are required in a high-temperature atmosphere such as automobile interior products, the strength is maintained, and even the nonwoven fabric for molding has the advantage of preventing sagging in a high-temperature atmosphere. It could be used for non-woven fabrics.

In addition, in the present invention, in order to impart flame retardancy, a phosphorus-based flame retardant may be added as a flame retardant during the polymerization reaction of the sheath and core portions, and the content ratio of the phosphorus-based flame retardant to the sheath portion to the core portion is 1:3. It is characterized by being ~3:1.

The phosphorus-based flame retardant may include the following [Chemical Formula 1].

[Formula 1]

(However, R1 and R2 are methyl, phenyl, halophenyl, alkyl, haloalkyl, or haloaryl.)

The phosphorus-based flame retardant may be used in both the sheath portion and the core portion, and it is preferable that the phosphorus-based flame retardant is included in each of 2,000 to 5,000 ppm in the polyester resin.

Hereinafter, an example of a method for manufacturing a polyester fiber for a binder with improved fairness according to the present invention is shown, but the present invention is not limited to the examples.

Example 1 to 3

3,000 ppm of phosphorus-based flame retardant was also added during the polymerization reaction of the core and sheath parts, and polyethylene terephthalate having a melt viscosity of about 2,300 poise at 280° C. was used as the core part, and the sheath part was a low melting point polyester Using a resin, the weight ratio of the sheath part and the core part is 50:50, and 0.5wt%, 1.5wt%, and 3.0wt% of the biodegradant polylactic acid are mixed in each, and the biodegradability of the present invention through a general complex spinning process A heat-adhesive composite binder fiber was prepared.

In the low melting point polyester resin, terephthalic acid (TPA) and ethylene glycol (EG) were added to an ester reaction tank, and a polymerization reaction was carried out at 258°C to prepare a polyethylene terephthalate polymer (PET oligomer) having a reaction rate of about 96%. I did. In the prepared polyethylene terephthalate (PET), 2-methyl-1,3-propanediol contained about 42 mol% of the diol component, and the content ratio of 2-methyl-1,3-pentanediol was shown in Table 1 below. The mixture was mixed with, and a transesterification catalyst was added to perform a transesterification reaction at 250±2°C. Then, a condensation polymerization reaction catalyst was added to the obtained reaction mixture, and a condensation polymerization reaction was carried out while controlling the final temperature and pressure in the reaction tank to be 280±2° C. and 0.1 mmHg, respectively.

Comparative example 1~4

Same as in Example 1, but the content of the biodegradant is shown in Table 1.

* Experiment method

(1) Tensile strength was measured by the evaluation method of ASTM D3822.

(2) Binder performance (adhesion) was confirmed through ASTM 5735, which is 50 GSM nonwoven fabric Tearing strength.

(3) Biodegradability was measured by ASTM 5511.

(4) Softening point (or melting point) and glass transition temperature (Tg) measurement

The glass transition temperature (Tg) of the copolymerized polyester resin was measured using a differential scanning calorimeter (Perkin Elmer, DSC-7), and the softening behavior was measured in TMA mode using a dynamic mechanical analyzer (DMA-7, Perkin Elmer). I did.

(5) Intrinsic viscosity (IV) measurement

The polyester resin was dissolved in a solution in which phenol and tetrachloroethane were mixed at a ratio of 1:1 by weight at a concentration of 0.5% by weight, and the intrinsic viscosity (I.V) was measured at 35°C using an Uberod viscometer.

(6) Melt viscosity measurement

After melting the polyester resin at the measurement temperature, the melt viscosity was measured using RDA-III of Rheometric Scientific. Specifically, when measured by setting from Initial Frequency = 1.0 rad/s to Final Frequency = 500.0 rad/s under Frequency Sweep condition at the set temperature, the value at 100 rad/s was calculated as the melt viscosity.

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Core part PET PET PET PET PET PET PET Biodegradation agent content in the core 0.5wt% 1.5wt% 3wt% 5wt% 0.1wt% 8.5wt% 0wt% Sheath Co-PET Co-PET Co-PET Co-PET Co-PET Co-PET Co-PET Biodegradation agent content in the cis part 0.5wt% 1.5wt% 3wt% 5wt% 0.1wt% 8.5wt% 0wt% Fairness Good Good Good Good Good Bad Good The tensile strength 3.2g/d 3.3g/d 3.0g/d 3.0g/d 3.3g/d 2.0g/d 3.3g/d Adhesiveness 15Kgf/cm2 14Kg/cm2 12Kgf/cm2 3Kgf/cm2 15Kgf/cm2 0.2Kgf/cm2 15Kgf/cm2 Biodegradable/400 days 71wt% 84wt% 86wt% 89wt% 15wt% 90wt% 2wt%

As shown in Table 1, Examples 1 to 3 are good in strength and adhesion, and biodegradability is good at 71 to 86 wt%, but Comparative Example 1 interferes with the adhesion of the sheath portion when an excessive amount of biodegradable components is mixed, and Comparative Example 2 The biodegradability is weak because there are too few biodegradable components, and Comparative Example 3 has a problem in the spinning process when the biodegradable component is 8.0 wt% or more, and Comparative Example 4 shows that when the biodegradable component is not added, the biodegradability rarely occurs at 2 wt%. Able to know.

division Softening point
(℃) Tg
(℃) IV
(dl/g) 2-methyl-1,3-pentanediol (mol%) Melt viscosity 220℃ 240℃ 260℃ Example 1 122 60.9 0.561 0.1 1254 1019 783 Example 2 119 61.8 0.562 0.5 1314 1078 864 Example 3 120 61.9 0.562 1.0 1528 1387 1196

As shown in Table 2, it can be seen that the melt viscosity increases as the content of 2-methyl-1,3-pentanediol increases, and in Examples 1 to 3, the melt viscosity of 260°C is all 700 poise or more, which is high at high temperature. It can be seen that the melt viscosity is maintained. In addition, in Examples 1 to 3 in which 2-methyl-1,3-pentanediol is contained in 0.1 to 1 mol% of the diol component, the difference between the melt viscosity at 220°C and the melt viscosity at 260°C corresponds to 300 to 500 poise. .

Claims (9)

In the biodegradable flame-retardant heat-adhesive composite binder fiber formed of a sheath portion and a core portion,
The core part is formed of a general polyester resin,
The cis portion is formed of an acidic component consisting of terephthalic acid or an ester-forming derivative thereof, and a diol component consisting of 2-methyl-1,3-propanediol, 2-methyl-1,3-pentanediol, and ethylene glycol. It is formed of polyester resin,
A biodegradant is included in the sheath and core parts,
The biodegradable agent is at least any one of aliphatic ester-based, aromatic ester-based, and monosaccharide (Polylactide),
Biodegradable flame-retardant heat-adhesive composite binder characterized in that the content ratio of the phosphorus-based flame retardant to the composite fiber is 0.3 to 0.5% by weight and the content ratio of the phosphorus-based flame retardant to the sheath and core is 1:3 to 3: fiber.
The method of claim 1,
The sheath part and the core part are in a weight ratio of 30:70 to 70:30,
The biodegradable heat-adhesive flame-retardant composite binder fiber, characterized in that 0.5 to 3.0% by weight of the biodegradable agent is included in the sheath portion and the core portion, respectively.
The method of claim 1,
The biodegradable heat-adhesive flame-retardant composite binder fiber characterized in that the flame retardant comprises the following [Chemical Formula 1] as a phosphorus-based flame retardant.
[Formula 1]

However, R1, R2 are methyl, phenyl, halophenyl, alkyl, haloalkyl, or haloaryl
The method of claim 1,
The composite binder fiber is a biodegradable heat-adhesive flame-retardant composite binder fiber characterized in that the core-sheath eccentric form or the core-sheath eccentric form or the side-by-side form.
The method of claim 1,
The biodegradable heat-adhesive flame-retardant composite binder fiber characterized in that the 2-methyl-1,3-pentanediol of the low melting point polyester resin contains 0.01 to 5 mol% of the diol component.
The method of claim 1,
The biodegradable heat-adhesive flame-retardant composite binder fiber, characterized in that the 2-methyl-1,3-pentanediol of the low-melting-point polyester resin contains 0.05-2 mol% of the diol component.
The method of claim 1,
The low melting point polyester resin is a biodegradable heat-adhesive flame-retardant composite binder fiber characterized in that the difference between the melt viscosity of 220°C and the melt viscosity of 260°C is 600 poise or less.
The method of claim 1,
The general polyester resin of the core part has a melt viscosity of 2,000-2,500 poise at 280°C, and the polyester resin of the sheath part has a melt viscosity of 600-1,500 poise at 260°C. Heat-adhesive flame-retardant composite binder fiber.
A nonwoven fabric comprising the biodegradable heat-adhesive flame-retardant composite binder fiber of any one of claims 1 to 8.