CN112695410B

CN112695410B - Fixed island type sea-island fiber, and preparation method and application thereof

Info

Publication number: CN112695410B
Application number: CN202011490712.8A
Authority: CN
Inventors: 彭超豪; 张初银; 张兵; 杨信实; 彭峰; 林上河
Original assignee: Zhejiang Huafon Synthetic Resin Co ltd
Current assignee: Zhejiang Huafon Synthetic Resin Co ltd
Priority date: 2020-12-16
Filing date: 2020-12-16
Publication date: 2023-05-23
Anticipated expiration: 2040-12-16
Also published as: CN112695410A

Abstract

The invention relates to a fixed island type sea-island fiber and a preparation method and application thereof, wherein the fixed island type sea-island fiber comprises polyurethane and water-soluble polyester in a mass ratio of (5-7) (5-3), the polyurethane is an island phase, and the water-soluble polyester is a sea phase. The fixed island fiber has excellent heat resistance and elasticity, and the polyurethane loss is small during the reduction. The island-shaped sea-island fiber is applied to the field of clothing or shoes requiring high elasticity.

Description

Fixed island type sea-island fiber, and preparation method and application thereof

Technical Field

The invention relates to the technical field of fibers, in particular to a fixed island type sea-island fiber, and a preparation method and application thereof.

Background

With the development of technology, microfiber products are increasingly used, such as clothing and lady long booties, which require some base fabrics with higher elasticity requirements, and some base fabrics even have four-sided stretch requirements, so that the requirements on the microfiber products are increasing. However, since it is difficult to achieve such elasticity by polyurethane resin alone, the fiber itself needs to have high elasticity, and thus, development of a fiber having high elasticity is desired to be suitable for the market.

At present, two raw materials of nylon and terylene are mainly applied to sea-island fibers, but the two raw materials are limited to the structure of the materials, and the elasticity of the spun fibers is limited and can not be improved in a quality, so that the spandex island fiber with high elasticity needs to be developed, and the microfiber base cloth with high elasticity can be manufactured.

CN110952335a discloses a weather-resistant fixed island sea-island fiber base cloth, a preparation method and application thereof, the disclosed weather-resistant fixed island sea-island fiber base cloth is prepared from the following components in parts by weight: 90-60 parts of terylene and 10-40 parts of weather-resistant polyurethane resin. The weather-resistant island-fixed sea-island fiber base cloth disclosed by the invention has a very good release structure, so that the microfiber base cloth has very excellent velvet feeling and meat feeling. Meanwhile, due to the introduction of ureido and aliphatic structures, the weather resistance of the product is greatly improved compared with that of a conventional product, and the color fastness of the base fabric is high. However, the weather-resistant islands-in-sea fiber base disclosed by the method cannot reduce the exercise of molecular chains in the polyurethane processing process, and the obtained fiber has poor elasticity.

CN103788636a discloses a polymer blend system for manufacturing high-fineness high-strength non-fixed island type PA6 superfine fiber, wherein the disclosed superfine fiber uses nylon 6 (PA 6) and low-density polyethylene as main polymers of the blend system, uses maleic anhydride modified linear low-density polyethylene as a compatilizer, and uses maleic anhydride modified ethylene propylene diene monomer as a toughening agent to jointly form the polymer blend system. The blending system can be used for preparing PA6/LDPE sea-island fiber, and the fineness of the finally dissolved PA6 superfine fiber can reach 0.0001dtex, has quasi-nanoscale size, and has better uniformity and strength. The non-woven fabric manufactured by the island fiber can obtain the non-island type PA6 superfine fiber synthetic leather base fabric through dipping wet polyurethane and methylbenzene deweighting, and then the superfine fiber synthetic leather with better hand feeling and higher strength can be obtained through post-finishing. However, when the base cloth is reduced, the sea-phase polyethylene needs to be removed through the reduction of a high-temperature toluene tank, and the polyurethane fiber is relatively thin, so that the polyurethane fiber is very easy to dissolve or swell in the toluene tank during the reduction, and the physical properties of the polyurethane fiber are seriously damaged.

In view of the above, it is important to develop an island-in-sea fiber having high elasticity and less polyurethane loss when it is reduced.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a fixed island type sea-island fiber, a preparation method and application thereof, wherein the fixed island type sea-island fiber has excellent heat resistance and elasticity, and the loss of polyurethane is small during the reduction.

To achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the present invention provides an islands-in-sea fiber comprising polyurethane and water-soluble polyester in a mass ratio of (5-7) (5-3), wherein 5-7 may be 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, etc., and 2-5 may be 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.2, 4.4, 4.6, 4.8, etc.;

the polyurethane is an island phase;

the water-soluble terylene is sea phase.

The island-fixing sea-island fiber takes polyurethane as island phase and water-soluble terylene as sea phase. When water-soluble polyester (COPET) is used as sea phase, hot water or low-concentration sodium hydroxide alkali solution can be used for replacing toluene to reduce the weight, so that the physical property loss degree of polyurethane in the fixed island fiber is reduced to the minimum. The mass ratio of the polyurethane to the water-soluble polyester is controlled within the range of (5-7) (5-3), so that the obtained fixed island type sea-island fiber has better elasticity and heat resistance, the polyurethane is excessively heavy, the water-soluble polyester cannot form sea phase, and part of the polyurethane is lost during the decrement; the water-soluble terylene has excessively heavy proportion, and the obtained fixed island type sea-island fiber has insufficient elasticity.

Preferably, the polyurethane is comprised in a polyester polyurethane and/or a polyether polyurethane.

Preferably, the polyurethane has a number average molecular weight of 80000 to 300000g/mol, e.g., 90000g/mol, 100000g/mol, 150000g/mol, 200000g/mol, 250000g/mol, etc.

Preferably, the number average molecular weight of the water-soluble polyester is 5000-80000g/mol, such as 10000g/mol, 20000g/mol, 30000g/mol, 40000g/mol, 50000g/mol, 60000g/mol, 70000g/mol, etc.

Preferably, the titer of the island fiber is 3 to 8dtex, for example, 4dtex, 5dtex, 6dtex, 7dtex, etc.

In a second aspect, the present invention provides a method for preparing the fixed island sea-island fiber according to the first aspect, the method comprising the steps of:

(1) Melting polyurethane raw materials, and then carrying out melt polycondensation reaction with polyurethane prepolymer to obtain polyurethane after chain extension;

(2) And spinning and pulling the chain-extended polyurethane and the melted water-soluble polyester to obtain the island-fixed sea-island fiber.

Preferably, the polyurethane raw material of step (1) further comprises a drying step before melting.

Preferably, the polyurethane raw material is dried to a mass concentration of 200ppm or less, for example, 180ppm, 150ppm, 120ppm, etc.

Preferably, the step (1) specifically includes: and drying the polyurethane raw material, melting in a first screw extruder, transferring to a second screw extruder, adding polyurethane prepolymer for melt polycondensation reaction, and obtaining the polyurethane after chain extension.

Preferably, the screw temperature of the first screw extruder is 150-200 ℃, e.g. 155 ℃, 160 ℃, 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃, etc.

Preferably, the screw temperature of the second screw extruder is 200-250 ℃, e.g. 205 ℃, 210 ℃, 215 ℃, 220 ℃, 225 ℃, 230 ℃, 235 ℃, 240 ℃, 245 ℃, etc.

Preferably, the temperature of the box of the second screw extruder is 220-260 ℃, for example 225 ℃, 230 ℃, 235 ℃, 240 ℃, 245 ℃, 250 ℃, 255 ℃, 260 ℃, etc. The box temperature refers to the temperature of a pipeline behind a melt spinning outflow screw and a region where a control spinneret plate is located.

Preferably, the addition amount of the polyurethane prepolymer in the step (1) is 1-10% of the total mass of the polyurethane raw material and the water-soluble terylene.

Preferably, the polyurethane prepolymer is prepared from a raw material comprising a combination of a polyester polyol and diphenylmethane diisocyanate (MDI).

Preferably, the molar ratio of the polyester polyol to the diphenylmethane diisocyanate is (1:1.5) - (1:3), such as 1:1.6, 1:1.8, 1:2, 1:2.2, 1:2.4, 1:2.6, 1:2.8, etc.

Preferably, the polyester polyol is prepared from a raw material comprising a combination of 1, 8-octylene glycol (MOD), 1, 9-nonylene glycol (ND) and Adipic Acid (AA).

The polyester polyol is prepared by polycondensation of MOD, ND and AA, wherein the MOD and the ND have side methyl groups and low crystallinity at a certain ambient temperature, and the formed polyester polyol and the polyurethane prepolymer synthesized by the MDI have high microphase separation tendency, so that the thermal stability and the elasticity are better.

Preferably, the total molar amount of MOD and ND is equal to the molar amount of AA.

Preferably, the molar ratio of MOD to ND is (1:1) - (1:4), e.g., 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, etc.

The prepolymer is prepared by reacting polyester polyol and MDI (methylene diphenyl diisocyanate) serving as raw materials in a certain proportion at the melting point temperature of the prepolymer.

Preferably, the step (1) further comprises adding a triol simultaneously with the polyurethane prepolymer.

Preferably, the amount of the triol added accounts for 1% -4% of the total mass of the polyurethane raw material and the water-soluble terylene, such as 1.5%, 2%, 2.5%, 3%, 3.5% and the like.

Preferably, the triol comprises glycerol.

Preferably, the water-soluble polyester fiber in the step (2) further comprises a pre-crystallization and drying operation before melting.

Preferably, the water-soluble polyester is pre-crystallized and then dried to less than 100ppm, for example, 90ppm, 80ppm, 70ppm, etc.

Preferably, the step (2) specifically includes: and (3) after pre-crystallizing and drying the water-soluble terylene, melting the terylene in a third screw extruder, spinning the terylene with the polyurethane after chain extension, and drawing to obtain the fixed island sea-island fiber.

Preferably, the screw temperature of the third screw extruder is 260-290 ℃, e.g., 265 ℃, 270 ℃, 275 ℃, 280 ℃, 285 ℃, 290 ℃, 295 ℃, etc.

Preferably, the box temperature of the third screw extruder is 270-300 ℃, for example 275 ℃, 280 ℃, 285 ℃, 290 ℃, 295 ℃ and the like.

Preferably, the spinning is performed at a rate of 300-800m/min, such as 400m/min, 500m/min, 600m/min, 700m/min, etc.

As a preferable technical scheme, the preparation method comprises the following steps:

(1) Drying polyurethane raw materials to a mass concentration below 200ppm, melting the dried polyurethane raw materials in a first screw extruder with a screw temperature of 150-200 ℃, transferring the melted polyurethane raw materials to a second screw extruder with a screw temperature of 200-250 ℃ and a box temperature of 220-260 ℃, and adding prepolymer and triol to perform melt polycondensation reaction to obtain polyurethane after chain extension;

(2) And (3) pre-crystallizing the water-soluble terylene, drying until the mass concentration is less than 100ppm, melting the terylene in a third screw extruder with the screw temperature of 260-290 ℃ and the box temperature of 270-300 ℃, spinning the terylene with the polyurethane after chain extension at the speed of 300-800m/min, and drawing to obtain the island-fixed sea-island fiber.

In a third aspect, the invention provides the use of the island-in-sea fiber of the first aspect in apparel or footwear.

Compared with the prior art, the invention has the following beneficial effects:

the island-fixing sea-island fiber takes polyurethane as island phase and water-soluble terylene as sea phase. When water-soluble terylene is used as sea phase, hot water or low-concentration sodium hydroxide alkali solution can be used for replacing toluene to reduce the weight, and the physical property loss degree of polyurethane in the island fiber can be reduced to the minimum. The invention can control the mass ratio of polyurethane and water-soluble terylene, so that the obtained fixed island type sea-island fiber has better elasticity and heat resistance. The fixed island sea-island fiber has an elongation of 173% or more, a loss rate of 2.9% or less, and good heat resistance.

Drawings

FIG. 1 is an island-type cross-sectional view of the island-shaped sea-island fiber obtained in example 1.

Detailed Description

To facilitate understanding of the present invention, examples are set forth below. It will be apparent to those skilled in the art that the examples are merely to aid in understanding the invention and are not to be construed as a specific limitation thereof.

Example 1

The present example provides a fixed island type sea-island fiber composed of an island phase polyurethane (polyester type polyurethane, number average molecular weight of 100000 g/mol) and a sea phase water-soluble polyester (number average molecular weight of 8000g/mol, available from various fiber materials research Inc. in Yangzhou, trade name AS 200) in a mass ratio of 6:4.

The microstructure of the fixed island type sea-island fiber is shown in figure 1, and analysis of figure 1 shows that the fixed island type sea-island fiber has uniform island type distribution, and the fiber diameter is about 4.5 mu m.

The preparation method of the fixed island type sea-island fiber comprises the following steps:

(1) Synthesizing polyester polyol by MOD, ND and AA in a molar ratio of 1:1.3:2.3, and synthesizing a prepolymer by the polyester polyol and MDI in a molar ratio of 1:2, wherein the total mass of the prepolymer is 5% of the total mass of the polyurethane raw material and the water-soluble terylene;

(2) Drying polyurethane raw material (purchased from Shenyang good luck plastic manufacturing Co., ltd., brand name is E-8968) until the mass concentration is 190ppm, melting the dried polyurethane raw material in a first screw extruder with the screw temperature of 180 ℃, transferring to a second screw extruder with the screw temperature of 225 ℃ and the box temperature of 220 ℃, adding prepolymer and glycerin (accounting for 2% of the total mass of the polyurethane raw material and water-soluble terylene) for melt polycondensation reaction, and obtaining polyurethane after chain extension;

(3) And (3) pre-crystallizing the water-soluble terylene, drying to the mass concentration of 90ppm, melting the terylene in a third screw extruder with the screw temperature of 275 ℃ and the box temperature of 290 ℃, spinning the terylene with the polyurethane after chain extension at the speed of 500m/min, and drawing to obtain the island-in-sea fiber (the fineness is 6 dtex).

Example 2

The present example provides a fixed island type sea-island fiber composed of an island phase polyurethane (a polyester type polyurethane of the kind having a number average molecular weight of 100000 g/mol) and a sea phase water-soluble polyester (a number average molecular weight of 8000 g/mol) in a mass ratio of 7:3.

(1) Synthesizing polyester polyol by MOD, ND and AA in a molar ratio of 1:2.8:3.8, and synthesizing a prepolymer by the polyester polyol and MDI in a molar ratio of 1:2.5, wherein the total mass of the prepolymer is 4% of the total mass of the polyurethane raw material and the water-soluble terylene;

(2) Drying polyurethane raw materials (purchased from Shenyang good luck plastic manufacturing Co., ltd., brand name is E-8968) until the mass concentration is 180ppm, melting the dried polyurethane raw materials in a first screw extruder with the screw temperature of 150 ℃, transferring the melted polyurethane raw materials to a second screw extruder with the screw temperature of 200 ℃ and the box temperature of 220 ℃, adding prepolymer and glycerin (accounting for 1 percent of the total mass of the polyurethane raw materials and water-soluble terylene) for melt polycondensation reaction, and obtaining polyurethane after chain extension;

(3) And (3) pre-crystallizing the water-soluble terylene, drying to the mass concentration of 75ppm, melting the terylene in a third screw extruder with the screw temperature of 290 ℃ and the box temperature of 270 ℃, spinning the terylene with the polyurethane after chain extension at the speed of 800m/min, and drawing to obtain the island-in-sea fiber (the fineness is 3 dtex).

Example 3

The present example provides a fixed island type sea-island fiber composed of polyurethane (polyether type polyurethane, number average molecular weight 120000 g/mol) of island phase and water-soluble polyester (number average molecular weight 20000 g/mol) of sea phase in a mass ratio of 6.5:3.5.

(1) Synthesizing polyester polyol by MOD, ND and AA in a molar ratio of 1:2:3, and synthesizing a prepolymer by the polyester polyol and the MDI in a molar ratio of 1:1.5, wherein the total mass of the prepolymer accounts for 8% of the total mass of the polyurethane raw material and the water-soluble polyester;

(2) Drying polyurethane raw materials (purchased from NOVEON and having the brand Estane 58280) until the mass concentration is 170ppm, melting the dried polyurethane raw materials in a first screw extruder with the screw temperature of 200 ℃, transferring the melted polyurethane raw materials to a second screw extruder with the screw temperature of 250 ℃ and the box temperature of 260 ℃, adding prepolymer and glycerol (accounting for 1.2 percent of the total mass of the polyurethane raw materials and the water-soluble terylene) for melt polycondensation reaction, and obtaining the polyurethane after chain extension;

(3) And (3) pre-crystallizing the water-soluble terylene, drying to the mass concentration of 80ppm, melting the terylene in a third screw extruder with the screw temperature of 270 ℃ and the box temperature of 300 ℃, spinning the terylene with the polyurethane after chain extension at the speed of 300m/min, and drawing to obtain the island-in-sea fiber (the fineness is 8 dtex).

Example 4

The difference between this example and example 1 is that the mass ratio of polyurethane to water-soluble polyester is 5.5:4.5, and the preparation method in this example is the same as that in example 1.

Example 5

The difference between this example and example 1 is that the mass ratio of polyurethane to water-soluble polyester is 7:3, and the preparation method in this example is the same as that in example 1.

Example 6

This example differs from example 1 in that no glycerol was added during the preparation.

Comparative example 1

This comparative example is different from example 1 in that the water-soluble polyester was replaced with low density polyethylene of equal quality (purchased from korean LG MB 9500), and the preparation method in this comparative example is the same as example 1.

Comparative example 2

The comparative example is different from example 1 in that the water-soluble polyester is replaced with a conventional polyester of equal quality, which is a non-water-soluble polyester (available from Zhejiang chemical fiber Co., ltd., brand SY 103), and the preparation method in the comparative example is the same as that of example 1.

Comparative example 3

The comparative example differs from example 1 in the mass ratio of polyurethane to water-soluble polyester 7.5:2.5, and the preparation method in the comparative example is the same as example 1.

Comparative example 4

The comparative example differs from example 1 in that the mass ratio of polyurethane to water-soluble polyester is 4:6, and the preparation method in the comparative example is the same as that of example 1.

Performance testing

Examples 1-6 and comparative examples 1-4 were tested as follows:

(1) Elongation rate: the test was performed as FZ/T50006.

(2) Loss rate of polyurethane after decrement: 10g of the fiber was put into the solution to be dissolved and reduced for 1 hour, and the reduced fiber was dried to obtain a weight a, a loss ratio x= (7-a)/7, wherein comparative examples 1-2 were subjected to benzene reduction, examples 1-6 and comparative examples 3-4 were subjected to water reduction (in alkali solution).

(3) Heat resistance (1-5 grades, 1 grade worst, 5 grades best): the fibers were placed in an oven at 160℃for 10min and rated 1-5 for color change and elastic decay rate, with 1 being the worst and 5 being the best.

TABLE 1

As can be seen from the analysis of the data in table 1, the island-in-sea fiber of the present invention has both good heat resistance and elasticity and less loss of polyurethane after reduction, and the island-in-sea fiber has an elongation of 173% or more and a loss of 2.9% or less, compared with the polyurethane fiber prepared by reduction of benzene.

Analysis of comparative examples 1-2 and example 1 revealed that comparative examples 1-2 did not perform as well as example 1, demonstrating that the island-in-sea fibers formed by selecting water-soluble polyester as the sea phase performed better.

Analysis of examples 4-5, comparative examples 3-4 and example 1 revealed that comparative examples 3-4 did not perform as well as examples 1 and examples 4-5, demonstrating that the polyurethane and water-soluble polyester had better properties than the island-in-sea fibers obtained in the (7-5): (3-5) range.

Analysis of example 6 and example 1 shows that example 6 has inferior performance to example 1, and that the island-in-sea fiber obtained by adding triol such as glycerin during the preparation process has better performance.

The applicant states that the detailed method of the present invention is illustrated by the above examples, but the present invention is not limited to the detailed method described above, i.e. it does not mean that the present invention must be practiced in dependence upon the detailed method described above. It should be apparent to those skilled in the art that any modification of the present invention, equivalent substitution of raw materials for the product of the present invention, addition of auxiliary components, selection of specific modes, etc., falls within the scope of the present invention and the scope of disclosure.

Claims

1. The fixed island type sea-island fiber with the elongation at break more than 218% and the loss rate within 2.2% is characterized by comprising polyurethane and water-soluble polyester with the mass ratio of (5-7): 5-3;

the polyurethane is an island phase;

the water-soluble terylene is in sea phase;

the number average molecular weight of the water-soluble terylene is 5000-80000g/mol;

the fineness of the fixed island type sea-island fiber is 3-8dtex;

the fixed island type sea-island fiber is obtained by a preparation method, which comprises the following steps:

(2) Spinning and dragging the chain-extended polyurethane and the melted water-soluble terylene to obtain the island-fixed sea-island fiber;

the step (1) further comprises the step of adding a triol while adding the polyurethane prepolymer;

the preparation raw materials of the polyurethane prepolymer comprise a combination of polyester polyol and diphenylmethane diisocyanate;

the preparation raw materials of the polyester polyol comprise a combination of 1, 8-octylene glycol, 1, 9-nonylene glycol and adipic acid;

the total molar amount of the 1, 8-octylene glycol and the 1, 9-nonylene glycol is equal to the molar amount of adipic acid;

the molar ratio of the 1, 8-octylene glycol to the 1, 9-nonylene glycol is 1: (2-4).

2. Island fiber according to claim 1, wherein said polyurethane comprises polyester polyurethane and/or polyether polyurethane.

3. The islands-in-sea fiber of claim 1 wherein the polyurethane has a number average molecular weight of 80000 to 300000g/mol.

4. A method for producing the fixed island fiber according to any one of claims 1 to 3, comprising the steps of:

5. The method of claim 4, wherein the polyurethane raw material of step (1) further comprises a step of drying before melting.

6. The method according to claim 5, wherein the polyurethane raw material is dried to a mass concentration of 200ppm or less.

7. The method according to claim 4, wherein the step (1) specifically comprises: and drying the polyurethane raw material, melting in a first screw extruder, transferring to a second screw extruder, adding polyurethane prepolymer for melt polycondensation reaction, and obtaining the polyurethane after chain extension.

8. The method of claim 7, wherein the first screw extruder has a screw temperature of 150-200 ℃.

9. The process of claim 7, wherein the second screw extruder has a screw temperature of 200-250 ℃.

10. The method of claim 7, wherein the second screw extruder has a box temperature of 220-260 ℃.

11. The preparation method of claim 4, wherein the addition amount of the polyurethane prepolymer in the step (1) is 1% -10% of the total mass of the polyurethane raw material and the water-soluble terylene.

12. The method of claim 1, wherein the molar ratio of the polyester polyol to the diphenylmethane diisocyanate is from (1:1.5) to (1:3).

13. The preparation method of claim 4, wherein the addition amount of the triol is 1-4% of the total mass of the polyurethane raw material and the water-soluble polyester.

14. The method of claim 4, wherein the triol comprises glycerol.

15. The method of claim 4, wherein the water-soluble polyester of step (2) further comprises a pre-crystallization and drying operation before melting.

16. The method of claim 15, wherein the water-soluble polyester is pre-crystallized and dried to less than 100 ppm.

17. The method according to claim 4, wherein the step (2) specifically comprises: and (3) after pre-crystallizing and drying the water-soluble terylene, melting the terylene in a third screw extruder, spinning the terylene with the polyurethane after chain extension, and drawing to obtain the fixed island sea-island fiber.

18. The method of claim 17, wherein the third screw extruder has a screw temperature of 260-290 ℃.

19. The process of claim 17, wherein the third screw extruder has a box temperature of 270-300 ℃.

20. The method of claim 17, wherein the spinning is performed at a rate of 300-800m/min.

21. The preparation method according to claim 4, characterized in that the preparation method comprises the steps of:

22. Use of the islands-in-sea fiber of any one of claims 1 to 3 in apparel or footwear.