CN114702666A - A kind of poly-m-phenylene isophthalamide fiber spinning raw material and preparation method and application thereof - Google Patents

Abstract

The invention provides a poly-m-phenylene isophthalamide fiber spinning raw material, a preparation method and application thereof, and belongs to the technical field of textile materials. A poly-m-phenylene isophthalamide fiber spinning raw material, the spinning raw material has a structure shown in the following formula, wherein R is an isocyanate intramolecular group. The preparation method is prepared by crosslinking the linear poly-m-phenylene isophthalamide containing phenolic hydroxyl group with diisocyanate. The preparation method of the poly-m-phenylene isophthalamide fiber spinning raw material of the invention is simple and feasible, the raw materials are cheap, and the obtained dynamic cross-linked high-performance poly-m-phenylene isophthalamide fiber spinning raw material has excellent performance. Through the high temperature reversible reaction between the phenolic hydroxyl group and the isocyanate, the crosslinking of the material can be achieved, and its performance can be improved.

Description

A kind of poly-m-phenylene isophthalamide fiber spinning raw material and preparation method and application thereof

technical field

The invention relates to the technical field of textile materials, in particular to a spinning raw material of poly-m-phenylene isophthalamide fiber and a preparation method and application thereof.

Background technique

Polyamide is a general term for polymers containing amide groups in the repeating units of the macromolecular main chain. With toughness, wear resistance, self-lubrication, and wide temperature range, it has become an engineering plastic that is widely used in the industry. Polyamide fiber has good comprehensive properties, including mechanical properties, heat resistance, wear resistance, chemical resistance and self-lubrication, and has a low coefficient of friction, a certain flame retardancy, easy processing, suitable for glass Fibers and other fillers are filled and enhanced to improve performance and expand application range. Among them, meta-aramid fiber is a kind of high-temperature resistant fiber with early development, wide application, large output and rapid development, and its total amount ranks second in special fibers. It has excellent high temperature resistance, good dimensional stability, excellent spinnability, fire resistance and corrosion resistance. On this basis, the introduction of some functional groups can improve some properties of composite materials, and some researches are currently exploring this aspect.

SUMMARY OF THE INVENTION

The purpose of the present invention is to propose a polym-phenylene isophthalamide fiber spinning raw material and its preparation method and application. The preparation method is simple and feasible, the raw material is cheap, and the performance is excellent. The reversible reaction can realize recycling and reduce environmental pollution and waste of resources.

The technical scheme of the present invention is realized as follows:

The present invention provides a kind of poly-m-phenylene isophthalamide fiber spinning raw material, and the spinning raw material has the structure shown in formula I:

Wherein, R is an isocyanate intramolecular group.

The present invention further protects a method for preparing the above-mentioned poly-m-phenylene isophthalamide fiber spinning raw material, which comprises cross-linking the linear poly-m-phenylene isophthalamide isophthalamide containing phenolic hydroxyl groups with diisocyanate to construct a dynamic cross-linking method. Linked polyamide material. Through the high-temperature reversible reaction between the phenolic hydroxyl group and the isocyanate, recycling can be realized, which reduces environmental pollution and resource waste.

Preferably, it is prepared from the following components in parts by weight: 1-20 parts of linear polymetaphenylene isophthalamide containing phenolic hydroxyl groups, 1-5 parts of diisocyanate, and 10-100 parts of solvent.

The solvent is one or a mixture of N-methylpyrrolidone, dimethyl sulfoxide, N,N'-dimethylacetamide, and N,N'-dimethylformamide.

As a further improvement of the present invention, the preparation method of the phenolic hydroxyl group-containing linear polymetaphenylene isophthalamide is as follows: uniformly mixing 5-hydroxyisophthalic acid and 1,3-phthalic acid in a solvent Then, polycondensation reaction is performed with m-phenylenediamine to obtain linear poly-m-phenylene isophthalamide containing phenolic hydroxyl groups.

As a further improvement of the present invention, the mass ratio of the 5-hydroxyisophthalic acid to 1,3-phthalic acid is (0.01-100):(0-99.9).

As a further improvement of the present invention, the solvent is one or a mixture of N-methylpyrrolidone, dimethyl sulfoxide, N,N'-dimethylacetamide, and N,N'-dimethylformamide .

As a further improvement of the present invention, the phenolic hydroxyl group-containing linear polymetaphenylene isophthalamide is prepared by precipitation with deionized water, repeated water washing and drying after the polycondensation reaction.

As a further improvement of the present invention, the diisocyanate is selected from at least one of aliphatic or alicyclic diisocyanates, aromatic diisocyanates, and molecules containing two isocyanate groups in the molecule.

As a further improvement of the present invention, the ratio of isocyanate groups to phenolic hydroxyl groups in the crosslinking reaction system is (0.01-1):1.

The present invention further protects an aromatic polyamide polymer fiber, which is characterized in that the above-mentioned poly-m-phenylene isophthalamide fiber spinning raw material is prepared by spinning, washing with water, drying and hot drawing. .

The present invention further protects the application of the above-mentioned aromatic polyamide-based high polymer fiber in the fields of preparing protective clothing, high-temperature filter material, electrical industry and composite materials.

The invention has the following beneficial effects: the invention provides a preparation method of a high-performance poly-m-phenylene isophthalamide fiber spinning raw material. The preparation method of the high-performance poly-m-phenylene isophthalamide fiber spinning raw material with dynamic cross-linking structure is simple and easy, and the raw materials are cheap, and the dynamic cross-linking high-performance poly-m-phenylene isophthalamide is obtained. Diamine fiber spinning raw material has excellent performance. Through the high temperature reversible reaction between the phenolic hydroxyl group and the isocyanate, the crosslinking of the material can be achieved, and its performance can be improved.

Detailed ways

The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Example 1

S1. Preparation of phenolic hydroxyl-containing polymetaphenylene isophthalamide:

Dissolve 10 parts by weight of 5-hydroxyisophthalic acid and isophthalic acid in 200 parts by weight of dimethyl sulfoxide according to a molar ratio of 1:1, add 10 parts by weight of m-phenylenediamine after mixing uniformly, and add 6 parts by weight of pyridine and 18 parts by weight of triphenyl phosphite were used as a catalyst to react at 130° C. for 5 hours to obtain a phenolic hydroxyl group-containing polymetaphenylene isophthalamide. The phenolic hydroxyl-containing poly-m-phenylene isophthalamide prepared in this example is separated out by deionized water, washed repeatedly and dried for many times.

S2. Preparation of poly-m-phenylene isophthalamide fiber spinning raw material:

10 parts by weight of the phenolic hydroxyl-containing polymetaphenylene isophthalamide prepared in Example 1 and 2 parts by weight of diisocyanate were dissolved in 100 parts by weight of N,N'-dimethylacetamide, and mixed uniformly Then, heating at 80 DEG C for 12 hours, a spinning raw material of poly-m-phenylene isophthalamide fiber is obtained.

S3. The poly-m-phenylene isophthalamide fiber obtained in step S2 is subjected to spinning, washing, drying, and thermal stretching (simultaneously thermally cross-linked) to obtain poly-m-phenylene isophthalamide fiber .

Example 2

The technical method and process are the same as in Example 1, and the difference from Example 1 is that the molar ratio of 5-hydroxyisophthalic acid and isophthalic acid is adjusted to be 0.5:1.

Example 3

The difference from Example 1 is that the molar ratio of 5-hydroxyisophthalic acid and isophthalic acid is adjusted to be 1:0.5, and other conditions are not changed.

Test Example 1

The fiber mechanical properties of Examples 1, 2, and 3 were tested, and the results are shown in Table 1. The test method implements the national standard GB/T14337-2008.

Table 1

Breaking Strength (cN) Elongation at break (%) Example 1 Product Fiber 2015 23.6 Example 2 Product Fiber 1960 22.3 Example 3 Product Fiber 2113 24.1

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (10)

1. a polym-phenylene isophthalamide fiber spinning raw material, is characterized in that, described spinning raw material has structure as shown in formula I:

Wherein, R is an isocyanate intramolecular group. 2. a preparation method of polymetaphenylene isophthalamide fiber spinning raw material as claimed in claim 1, is characterized in that, by the linear polymetaphenylene isophthalamide isophthalamide containing phenolic hydroxyl group and diphenylene isophthalamide Isocyanate cross-linked in the system. 3. preparation method according to claim 2, is characterized in that, the preparation method of described linear polymetaphenylene isophthalamide containing phenolic hydroxyl group is: by 5-hydroxyisophthalic acid and 1,3 - After phthalic acid is uniformly mixed in a solvent, polycondensation reaction is carried out with m-phenylenediamine to obtain a linear poly-m-phenylene isophthalamide containing phenolic hydroxyl groups. 4. The preparation method according to claim 3, wherein the mass ratio of the 5-hydroxyisophthalic acid to 1,3-phthalic acid is (0.01-100):(0-99.9). 5. The preparation method according to claim 3, wherein the solvent is N-methylpyrrolidone, dimethyl sulfoxide, N,N'-dimethylacetamide, N,N'-dimethylacetamide One or a mixture of carboxyamides. 6 . The preparation method according to claim 3 , wherein the phenolic hydroxyl group-containing linear polymetaphenylene isophthalamide is obtained by precipitation with deionized water, repeated washing with water and drying after the polycondensation reaction. 7 . 7. preparation method according to claim 2 is characterized in that, described diisocyanate is selected from at least one in aliphatic or alicyclic diisocyanate, aromatic diisocyanate, molecule containing two isocyanate groups in molecule kind. 8 . The preparation method according to claim 2 , wherein the ratio of isocyanate groups to phenolic hydroxyl groups in the cross-linking reaction system is (0.01-1):1. 9 . 9. An aromatic polyamide-based high polymer fiber, characterized in that, after spinning, washing, drying, and hot drawing the poly-m-phenylene isophthalamide fiber spinning raw material according to claim 1 be made of. 10. The application of the aromatic polyamide polymer fiber according to claim 9 in the fields of preparing protective clothing, high temperature filter material, electrical industry and composite materials.