TWI843691B - Dyeable fiber and preparation method thereof - Google Patents

Abstract

A dyeable fiber and a preparation method thereof are provided. The dyeable fiber includes polypropylene and polyolefin modified copolymers. The polyolefin modified copolymer has at least one amide group, selected from the following structures of Formula (I) to Formula (IV):

Description

Dyeable fiber and preparation method thereof

The present disclosure relates to a fiber and a method for preparing the same, and in particular to a dyeable fiber and a method for preparing the same.

Polypropylene (PP) fiber is currently the only material that is synthesized from the byproduct of oil refining. Its spinning and dyeing temperatures are low, and compared with the current mainstream polyester and nylon fiber raw materials, it has lower carbon emissions and energy consumption. However, polypropylene fiber is not polar and can only be dope-dyed. Although the obtained fiber has advantages such as water resistance, low cost, and low environmental pollution, it is only suitable for mass production and still has disadvantages such as dull color and large color change loss. Due to the lack of breakthroughs in dyeing technology and poor color fastness to washing, polypropylene fiber has difficulty entering the market of popular clothing textiles with high color characteristics, and it is also difficult to adapt to the fashion industry where clothing colors change rapidly.

In the traditional polyester blending grafting modification technology, polypropylene-g-Maleic Anhydride (PP-g-MA) is added to melt-blend polyester fiber (PET) and PP, and then dyed with disperse dyes. This traditional technology has performance defects to varying degrees, such as low color fastness, poor spinnability, poor fiber strength, inability to spin fine yarns, and inability to achieve industrialization.

Therefore, developing a dyeable polypropylene fiber and a preparation method thereof to improve dyeability and enhance color fastness to washing, thereby meeting the market demand for high-color fashionable clothing textiles, is an important topic in the current industry.

The present invention discloses a dyeable fiber and a preparation method thereof. By blending a modified polyolefin copolymer with polypropylene, the polypropylene fiber is endowed with low-temperature dyeability in combination with acid dyes, thereby improving the color fastness to washing to reach the commercial grade 3 to 4 standard.

The dyeable fiber disclosed herein comprises polypropylene and a polyolefin modified copolymer. The polyolefin modified copolymer has at least one amide group selected from the following structures of formula (I) to formula (IV): In the structures of Formula (I) to Formula (IV), R is independently H or C2 to C16 alkyl, n is independently an integer from 2 to 5, p is independently an integer from 23 to 224, and q is independently an integer from 19 to 210.

Based on the above, the present disclosure provides a dyeable fiber and a preparation method thereof, wherein a polyolefin maleic anhydride copolymer is subjected to amination modification, an amide group is reacted to the polyolefin polymer side chain, and then melt blended with PP, and then dyed with an acid dye. The amide group introduced into the side chain can be chemically ionically bonded with the acid dye, and the color fastness is high, and the compatibility and spinnability of the blended copolymer are good.

The following will describe the embodiments of the present disclosure in detail. However, these embodiments are exemplary and the present disclosure is not limited thereto.

In this article, the range expressed by "a value to another value" is a summary expression method to avoid listing all the values in the range one by one in the specification. Therefore, the description of a specific numerical range covers any numerical value in the numerical range and the smaller numerical range defined by any numerical value in the numerical range, just as the arbitrary numerical value and the smaller numerical range are written in the description text in the specification.

The dyeable fiber disclosed herein comprises polypropylene and a polyolefin modified copolymer. The polyolefin modified copolymer has at least one amide group selected from the following structures of formula (I) to formula (IV): In the structures of Formula (I) to Formula (IV), R is independently H or C2 to C16 alkyl, n is independently an integer from 2 to 5, p is independently an integer from 23 to 224, and q is independently an integer from 19 to 210.

In the structures of the above formula (I) to formula (IV) of the present disclosure, R may independently be H, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, C9 alkyl, C10 alkyl, C11 alkyl, C12 alkyl, C13 alkyl, C14 alkyl, C15 alkyl or C16 alkyl, but the present disclosure is not limited thereto. n may independently be 2, 3, 4 or 5, but the present disclosure is not limited thereto. p may independently be an integer from 25 to 220, an integer from 30 to 200, an integer from 40 to 180, an integer from 50 to 150, an integer from 60 to 120, etc., but the present disclosure is not limited thereto. q may independently be an integer from 20 to 200, an integer from 30 to 180, an integer from 40 to 160, an integer from 50 to 150, etc., but the present disclosure is not limited thereto.

In the structures of the above formula (I) to formula (IV) of one embodiment of the present disclosure, R may be independently H, n may be independently 3, p may be independently 23, and q may be independently 19. More specifically, in the structure of formula (I) or formula (II), R may be independently H, n may be independently 3, p may be independently 23, and q may be independently 19, which can be represented by the chemical structures of compound 1 (abbreviated as r-PE-4N) and compound 2 (abbreviated as r-PE-2N) of Preparation Example 1 and Preparation Example 2 below, respectively.

In one embodiment of the present disclosure, the polyolefin modified copolymer can be selected from the following specific structures, but the present disclosure is not limited thereto: .

In one embodiment of the present disclosure, based on the total weight of the dyeable fiber as 100 wt%, the content of polypropylene can be 80 wt% to 95 wt%, and the content of the polyolefin modified copolymer can be 5 wt% to 20 wt%. In the above-mentioned dyeable fiber, based on the total weight of the dyeable fiber as 100 wt%, the content of polypropylene can be, for example, 82 wt%, 85 wt%, 87 wt%, 88 wt%, 90 wt%, 92 wt%, 93 wt%, 94 wt%, etc., but the present disclosure is not limited thereto. In the above-mentioned dyeable fiber, based on the total weight of the dyeable fiber as 100 wt%, the content of the polyolefin modified copolymer can be, for example, 6.5 wt%, 8.5 wt%, 10 wt%, 12.5 wt%, 15 wt%, 17.5 wt%, 19 wt%, etc., but the present disclosure is not limited thereto.

In one embodiment of the present disclosure, the dyeable fiber is suitable for dyeing with an acid dye, and the dyeing temperature can be 70°C to 100°C, for example, 72°C to 98°C, 75°C to 95°C, 80°C to 90°C, etc., but the present disclosure is not limited thereto. The above-mentioned acid dye includes LN-183, LY-181, LR58 or a combination thereof, but the present disclosure is not limited thereto.

In one embodiment of the present disclosure, the preparation method of dyeable fiber is: firstly, polyolefin maleic anhydride copolymer is modified by amination, amide groups are reacted to the side chains of polyolefin polymer, then melt blended with polypropylene, and then dyed with acid dye. Among them, the introduction of amide groups in the side chains can form chemical ion bonds with acid dyes, thereby increasing color fastness. In addition, the compatibility and spinnability of the blended copolymer of polyolefin and polypropylene are good. The principle of acid dyeing is mainly to use cationic groups as binding anchors to establish ionic bonds with negatively charged groups (sulfonic acid groups in acid dyes), as shown in the following chemical formula:

In one embodiment of the present disclosure, a method for preparing dyeable fibers comprises the following steps. First, a polyolefin maleic anhydride copolymer is subjected to amination modification to obtain a polyolefin modified copolymer, wherein the polyolefin modified copolymer has at least one amide group and is selected from the following structures of formula (I) to formula (IV): In the structures of formula (I) to (IV), R is independently H or C2 to C16 alkyl, n is independently an integer from 2 to 5, p is independently an integer from 23 to 224, and q is independently an integer from 19 to 210. Then, the polypropylene and the polyolefin modified copolymer are melt-spun to produce dyeable fibers, and the melt-spinning method includes blending with a single screw, a twin screw or a combination thereof.

In one embodiment of the present disclosure, polypropylene and polyolefin modified copolymer are melt-spun at a weight percentage of 80 wt% to 95 wt% and 5 wt% to 20 wt%. In the melt spinning method, the spinning temperature can be 220°C to 250°C, for example, 222°C to 248°C, 225°C to 245°C, 230°C to 240°C, etc., but the present disclosure is not limited thereto. The spinning speed can be 800 m/min to 3000 m/min, for example, 900 m/min to 2800 m/min, 1000 m/min to 2600 m/min, etc., but the present disclosure is not limited thereto.

In the above-mentioned method for preparing dyeable fibers, the applicable ranges of R, n, p, q, the applicable weight percentage (wt%) of polypropylene and polyolefin modified copolymer, and the applicable melt spinning temperature and speed are as shown above and will not be elaborated here.

In one embodiment of the present disclosure, the modified copolymer of polypropylene and polyolefin is melt-spun at 85 wt% and 15 wt%, the spinning temperature is 235°C, and the spinning speed is 1000 m/min. For example, in the embodiments of Compound 1 (abbreviated as r-PE-4N) and Compound 2 (abbreviated as r-PE-2N) of Preparation Example 1 and Preparation Example 2 below, the melt-spinning can be performed at 85 wt% and 15 wt%, respectively, the spinning temperature is 235°C, and the spinning speed is 1000 m/min.

In one embodiment of the present disclosure, the polyolefin modified copolymer is obtained by amination modification of a polyolefin maleic anhydride copolymer. More specifically, the present disclosure synthesizes two polyolefin aminated compounds (r-PP-4N, r-PP-2N), introduces amino groups, and increases the number of dyeing functional groups that can be combined with acid dyes. The chemical reaction formula is shown below, but the present disclosure is not limited to this. In reaction formula 1, the condensing agent is, for example, TPP, and the reaction temperature is, for example, 120°C to 180°C. In reaction formula 2, the reaction temperature is, for example, 180°C to 200°C. Reaction 1 Reaction 2

The dyeable fiber and its preparation method disclosed above are described in detail below by means of preparation examples and experimental examples. However, the following experimental examples are not intended to limit the present disclosure.

In order to prove that the dyeable fiber and its preparation method proposed in the present disclosure can improve low-temperature dyeability and enhance water washing color fastness, the relevant preparation process and test are specifically listed below. Preparation Example 1 : Preparation of Compound 1 ( abbreviated as r-PE-4N)

Take 5 g (0.04 mol) of polyethylene-alt-maleic anhydride (Poly(ethylene-alt-maleic anhydride)，PEMA), 6.1 g (0.06 mol) of N,N-dimethyl-1,3-diaminopropane (N,N-Dimethyl-1,3-propanediamine，DMAPA) and 20 ml of toluene and add them to a reaction bottle. Then heat the reaction bottle to 120℃ and react for 18 hours. After cooling to room temperature and solid precipitation, pour the reaction solution into n-hexane and let it stand to continue to precipitate the product. The obtained product is filtered and washed and then dried in an oven at 80℃ to obtain 4.7 g of white solid powder intermediate product.

Take 10.2 g (0.05 mol) of the intermediate product, 51 g (0.5 mol) of N,N-Dimethyl-1,3-propanediamine, 15.51 g (0.05 mol) of TPP (Triphenyl phosphite) and 5 ml of pyridine and add them to a 100 ml reaction bottle. Then heat the reaction bottle to 120°C and react for 18 hours. After cooling to room temperature, pour the reaction solution into n-hexane to precipitate the product. The obtained product is filtered, washed, and dried in an oven at 80°C to obtain 9.6 g of white solid powder compound 1. Preparation Example 2 : Preparation of Compound 2 ( abbreviated as r-PE-2N)

204 g (1 mol) of the intermediate product was placed in a release paper tray and then placed in a reaction bottle. The reaction bottle was then placed in a 180°C heating container and vacuumed for 6 hours. After cooling to room temperature and the powder solidified into a solid, the solid was crushed and the obtained product was dried in an oven at 80°C to obtain 183.6 g of a yellow solid powder compound 2 cyclization product. Experimental Example Experimental Example 1

Take 7.5 g (15 wt%) of the compound 1 obtained in the above-mentioned preparation example 1 and 42.5 g of polypropylene, mix them evenly in advance and put them into a bottle. Then use a small twin-screw to mix (190°C). After washing, the product is dried in a vacuum oven at 80°C to obtain particles, and the obtained particles are analyzed. Experimental Example 2

Take 180 g (15 wt%) of the closed-ring product of compound 2 obtained in the above-mentioned preparation example 2 and mix it evenly with 1020 g of polypropylene in advance and put it into a bottle. Then use a small twin-screw to mix. After washing, the product is dried in a vacuum oven at 80°C to obtain particles, and the obtained particles are analyzed. Experimental Example 3

Take 60 g (5 wt%) of the closed-ring product of compound 2 obtained in the above-mentioned preparation example 2 and mix it evenly with 1140 g of polypropylene in advance and put it into a bottle. Then use a small twin-screw to mix. After washing, the product is dried in a vacuum oven at 80°C to obtain particles, and the obtained particles are analyzed. Comparative Example Comparative Example 1

300 g (25 wt%) of the closed-ring product of compound 2 and 900 g of polypropylene were mixed uniformly in advance and then placed in a bottle. Then, a small twin-screw was used for mixing. The product was washed and dried in a vacuum oven at 80°C to obtain particles, which were then analyzed. Comparative Example 2

1200 g of 100 wt% PP was placed in a bottle and dried in a vacuum oven at 80°C to obtain particles. Spinning step The particles obtained from Experimental Examples 1 to 3 and Comparative Examples 1 and 2 were placed in a vacuum oven at 120°C for 24 hours. The particles were added to a screw extruder and sent to a metering pump after extrusion and melting. The metering pump controls and ensures that the polymer melt flows steadily into the spinning box for spinning. The spinning temperature is 235°C, the spinning speed is 1000 m/min, and the spinning nozzle is 24F 0.5 mm. Experimental Examples 1 to 3 and Comparative Example 2 can be wound for 10 minutes without floating, but Comparative Example 1 cannot be wound for 10 minutes without floating. Tensile Strength Test

Use USTER tensile testing machine to test the tensile strength of fibers (standard method CNS13785L3245). Dyeing strength and K/S improvement multiple

The test is conducted using CIE L*a*b color difference. Washing fastness

Washing fastness test was performed using standard method AATCC61.

Prepare dye solution, the formula of dye solution is as follows: dye 3% owf (On weight of fabric, weight ratio of dye to fabric), auxiliaries (leveling agent, (NH ₄ ) ₂ SO ₄ ). Open the water inlet valve of the dyeing machine, put the water to a certain level, turn on the electric heating switch, temperature control switch and electric stirrer. Suck the prepared dye solution into the dyeing tube and put it in the dyeing machine. When the temperature reaches the dyeing starting temperature of 60℃, put the sample socks to be dyed into the dye solution for 20 minutes, then heat it to 110℃ at a rate of 1℃/min, keep it for 90 minutes to 100 minutes, then stop the machine and stop heating, place it in a water bath for 30 minutes to cool down to 60℃, take it out and cool it naturally to room temperature, and finally rinse and squeeze the socks with a washing bottle.

The test results of Experimental Examples 1 to 3, Comparative Examples 1 and 2 are shown in Table 1 below. All of them were spun under the same conditions (spinning temperature 225°C, winding speed 1000 m/min) and dyed with the same acid dye (LN-183). It can be seen from Table 1 that compared with Comparative Example 2 with 100 wt% PP, Experimental Examples 1, 2 and 3 all have good fiber properties, are obviously colored after dyeing, and have a water washing fastness that reaches the commercial standard of grade 3.5. Because the addition ratio of the modified copolymer of polyolefin in Comparative Example 1 is too high, which exceeds the addition range disclosed in this disclosure, the spinnability is poor, and the continuous spinning breaks in less than 2 minutes. The dyeing strength of Comparative Example 2 is quite low, and the water washing fastness cannot be measured. Table 1 Experimental Example 1 Experimental Example 2 Experimental Example 3 Comparison Example 1 Comparison Example 2 Winding time @1000 m/min ≥ 10 min ≥ 10 min ≥ 10 min ≤ 2 ≥ 10 min Tensile strength (g/d) 4.56 5.01 4.59 1.02 5.13 Dyeing strength (K/S) 5.03 (600 nm) 3.47 (600 nm) 1.71 (600 nm) - 0.23 (600 nm) K/S improvement multiple 21.9x 15.1x 7.4x - - Washing fastness 3.5 3.5 3.5 - -

In summary, the present disclosure provides a dyeable fiber and a preparation method thereof, wherein polyolefin maleic anhydride copolymer is modified by amination, amide groups are reacted to the side chains of polyolefin polymers, and then melt blended with PP, thereby giving polypropylene fiber low-temperature dyeability combined with acid dyes, and improving water washing color fastness to achieve commercial grade 3 to 4, which meets the market demand for popular clothing textiles with high color and the commercial demand of the fashion industry. The amide groups introduced into the side chains can form chemical ion bonds with acid dyes, have high color fastness, and the blended copolymer is polyolefin and PP, which has good compatibility and good spinnability.

without

without

Claims (10)

A dyeable fiber comprises: polypropylene; and a polyolefin modified copolymer having at least one amide group selected from the following structures of formula (I) to formula (IV): In the structures of Formula (I) to Formula (IV), R is independently H or C2 to C16 alkyl, n is independently an integer from 2 to 5, p is independently an integer from 23 to 224, and q is independently an integer from 19 to 210. The dyeable fiber as described in claim 1, wherein the content of the polypropylene is 80 wt% to 95 wt%, and the content of the polyolefin modified copolymer is 5 wt% to 20 wt%, based on the total weight of the dyeable fiber being 100 wt%. The dyeable fiber as described in claim 1, wherein the dyeable fiber is suitable for dyeing with acid dyes at a dyeing temperature of 70°C to 100°C. The dyeable fiber as described in claim 3, wherein the acid dye comprises LN-183, LY-181, LR58 or a combination thereof. The dyeable fiber as claimed in claim 1, wherein the polyolefin modified copolymer is selected from the following structures: . A method for preparing dyeable fibers comprises: performing amination modification on a polyolefin maleic anhydride copolymer to obtain a polyolefin modified copolymer, wherein the polyolefin modified copolymer has at least one amide group and is selected from the following structures of formula (I) to formula (IV): In the structures of formula (I) to (IV), R is independently H or C2 to C16 alkyl, n is independently an integer from 2 to 5, p is independently an integer from 23 to 224, and q is independently an integer from 19 to 210; and polypropylene and the polyolefin modified copolymer are melt-spun to produce the dyeable fiber. A method for preparing dyeable fibers as described in claim 6, wherein the melt spinning method includes blending with a single screw, a twin screw or a combination thereof. The method for preparing dyeable fibers as described in claim 6, wherein the polypropylene and the polyolefin modified copolymer are melt-spun in weight percentages of 80 wt% to 95 wt% and 5 wt% to 20 wt%. A method for preparing dyeable fibers as described in claim 6, wherein during the melt spinning, the spinning temperature is 220° C. to 250° C., and the spinning speed is 1000 m/min to 3000 m/min. The method for preparing dyeable fibers as described in claim 6, wherein the polyolefin modified copolymer is selected from the following structures: .