阅读说明：本技术 一种基于酶促转化和催化氧化的导电真丝制备方法 (Preparation method of conductive real silk based on enzymatic conversion and catalytic oxidation ) 是由 王平 周舟 农叶琳 张恒玮 倪叶舟 余圆圆 于 2019-09-17 设计创作，主要内容包括：本发明公开了一种基于酶促转化和催化氧化的导电真丝制备方法,利用酪氨酸酚裂解酶催化真丝纤维中的丝氨酸转化成酪氨酸；再借助漆酶催化氧化真丝纤维中酪氨酸与苯胺自由基反应,通过酶促真丝纤维大分子与苯胺接枝聚合,形成与纤维结合的聚苯胺大分子,实现导电真丝的制备。具体包括以下步骤：(1)酶催化丝氨酸转化；(2)酶促真丝与苯胺接枝聚合。与传统通过金属喷涂法、涂层法和浸轧焙烘法制备导电真丝相比,本发明述及的方法具有生产能耗较低,导电效果改善,且真丝纤维强力增加的优点。(The invention discloses a method for preparing conductive real silk based on enzymatic conversion and catalytic oxidation, which uses tyrosine phenol lyase to catalyze and convert serine in real silk fiber into tyrosine; and then, the laccase is used for catalyzing and oxidizing tyrosine in the real silk fiber to react with aniline free radicals, and the enzymatic real silk fiber macromolecules and aniline are subjected to graft polymerization to form polyaniline macromolecules combined with the fibers, so that the preparation of the conductive real silk is realized. The method specifically comprises the following steps: (1) enzyme-catalyzed serine conversion; (2) enzymatic real silk and aniline graft polymerization. Compared with the traditional method for preparing the conductive real silk by a metal spraying method, a coating method and a padding and baking method, the method has the advantages of lower production energy consumption, improved conductive effect and increased strength of real silk fiber.)

1. a method for preparing conductive real silk based on enzymatic conversion and catalytic oxidation, which utilizes tyrosine phenol lyase to catalyze serine in real silk fiber to be converted into tyrosine; and then, laccase is used for catalyzing and oxidizing tyrosine in the real silk fibers to react with aniline free radicals, and the real silk and the aniline are subjected to graft polymerization to form polyaniline macromolecules, so that the conductive real silk is prepared.

2. the method for preparing the conductive real silk based on the enzymatic conversion and the catalytic oxidation as claimed in claim 1, which is characterized by comprising the following steps:

(1) enzymatic serine conversion: soaking real silk fiber in a tyrosine phenol lyase and a phenol solution to catalyze the conversion of serine in the real silk fiber into tyrosine; washing with water; drying;

(2) enzymatic real silk and aniline graft polymerization: dipping the real silk fabric treated in the step (1) in an aniline monomer solution, adding laccase, and catalyzing the reaction of the leucine and aniline free radicals in the real silk fiber; washing with water; and (5) drying.

3. The method for preparing conductive silk thread based on enzymatic conversion and catalytic oxidation according to claim 2, wherein in the step (1), the formulation of the tyrosine phenol lyase and the phenol solution is as follows: 10-100U/mL of tyrosine phenol lyase, 1-10 g/L of phenol, 0.5-5 g/L of pyridoxal phosphate, 0.5-2 g/L of ammonium chloride and pH of 6-8.

4. the method for preparing the conductive silk based on the enzymatic conversion and the catalytic oxidation as claimed in claim 2, wherein in the step (1), the reaction conditions are as follows: the temperature is 30-50 ℃, the time is 12-24 hours, and the bath ratio is 1: 40.

5. The method for preparing the conductive real silk based on the enzymatic conversion and the catalytic oxidation as claimed in claim 2, wherein in the step (1), the washing is carried out in deionized water at 40-50 ℃ for 5-10 minutes, and the drying is carried out at 50-60 ℃.

6. the method for preparing conductive real silk based on enzymatic conversion and catalytic oxidation as claimed in claim 2, wherein in the step (2), the aniline concentration in the aniline monomer solution is: 1-4 g/L, pH 4-5.5 of aniline, and the laccase addition amount is as follows: 0.2 to 1U/mL.

7. the method for preparing the conductive silk based on the enzymatic conversion and the catalytic oxidation as claimed in claim 2, wherein in the step (2), the reaction conditions are as follows: the temperature is 30-45 ℃, the treatment time is 12-48 hours, and the bath ratio is 1: 40.

8. The method for preparing the conductive real silk based on the enzymatic conversion and the catalytic oxidation as claimed in claim 2, wherein in the step (2), the washing is carried out in deionized water at 40-50 ℃ for 5-10 minutes, and the drying is carried out at 50-60 ℃.

9. real silk fiber prepared by the method for preparing conductive real silk based on enzymatic conversion and catalytic oxidation according to any one of claims 7 to 8.

Technical Field

The invention relates to a preparation method of conductive real silk based on enzymatic conversion and catalytic oxidation, belonging to the technical field of textile biology.

background

the silk fiber consists of sericin and fibroin, wherein in the degumming treatment, the sericin component with a spherical protein structure is dissolved by an alkaline agent or hydrolyzed by protease, and the fibroin with higher chemical stability is reserved. The silk fiber product has silk fibroin as main component and excellent application performance including excellent hand feeling, elegant luster and excellent moisture absorption. On the other hand, as protein fibers, the real silk fabrics have obvious electrostatic phenomena in the production and use processes, the accumulation of electrostatic charges easily causes dust adhesion, and the entangled limbs of the clothes generate uncomfortable adhesion feeling, which affects the wearing comfort degree.

In order to eliminate the static electricity of textile fibers such as real silk and the like and fabrics thereof, researchers have made preparation researches of conductive fibers. The existing methods include metal spraying, coating and post-finishing. The metal spraying method is to deposit metal on the surface of the fiber by vacuum spraying or electrochemical method, so that the fiber has metal-like conductivity, and the defects are that the fiber has poor hand feeling and difficult cohesion, and the use of the fiber is limited to a certain extent. The coating method is to coat carbon black on the surface of common fiber by using an adhesive or directly bond the fiber and the carbon black by hot pressing, and has the defects that the carbon black is easy to fall off and is not good in hand feeling, and the carbon black is not easy to be uniformly distributed on the surface of the fiber. The post-treatment method adopts hydrophilic antistatic finishing agent, and the hydrophilic antistatic finishing agent is applied to the surface of real silk fiber by a dipping, padding and baking method to form a continuous conductive film on the surface of the fiber.

The biological enzyme method has the advantages of safety, high efficiency, specificity, environmental friendliness and the like. Laccase, as a polyphenol oxidase, can catalyze and oxidize aniline to generate free radicals, initiate intermolecular polymerization, and form conductive polyaniline macromolecules. In addition, the silk fibroin contains a certain amount of tyrosine, and laccase can also catalyze and oxidize phenolic hydroxyl on the tyrosine to generate a quinone active group with strong reactivity; the quinone active groups can be subjected to graft polymerization with aniline free radicals to form polyaniline connected with real silk fiber macromolecules, and an idea is provided for preparing real silk fibers with a lasting conductive effect.

on the other hand, the tyrosine in the silk fiber macromolecules is limited and mostly distributed in the macromolecular chains consisting of alanine and glycine with strong hydrophobicity, so that the accessibility of laccase to the tyrosine is influenced to different degrees, and the effect of the laccase in catalyzing the graft polymerization of the silk and aniline is reduced. In order to solve the problem, the tyrosine phenol lyase is used for catalyzing and converting the serine with high content in the real silk fiber into the tyrosine according to the characteristic that the tyrosine phenol lyase can catalyze the reaction of the serine and the phenol to convert the serine into the tyrosine, so that the number of the tyrosine in the real silk fiber is increased, and the reactivity of the real silk fiber in the laccase catalytic oxidation is improved. On the basis, on one hand, the laccase can catalyze and oxidize tyrosine in the real silk fibers to initiate cross-linking between silk fibroin molecules, so that the strength of the real silk fibers is increased; on the other hand, laccase can also catalyze the reaction of oxidized tyrosine and aniline free radicals, and the preparation of the conductive real silk is realized through the graft polymerization of enzymatic real silk and aniline.

Disclosure of Invention

the purpose of the invention is as follows: aiming at the technical problems, the invention aims to provide a method for preparing conductive real silk based on enzymatic conversion and catalytic oxidation, which can increase the tyrosine content in real silk fiber and improve the reactivity of real silk fiber by means of an enzymatic method; laccase is combined to catalyze the free radical graft polymerization of the real silk fiber and aniline, so that the conductivity of the real silk fiber is improved, and the preparation of the conductive real silk fiber based on an enzyme method is realized.

the technical scheme is as follows: in order to solve the technical problems, the invention adopts the following technical scheme:

A method for preparing conductive real silk based on enzymatic conversion and catalytic oxidation, which utilizes tyrosine phenol lyase to catalyze serine in real silk fiber to be converted into tyrosine; and then, laccase is used for catalyzing and oxidizing tyrosine in the real silk fibers to react with aniline free radicals, and the real silk and the aniline are subjected to graft polymerization to form polyaniline macromolecules, so that the conductive real silk is prepared.

the preparation method of the conductive real silk based on enzymatic conversion and catalytic oxidation specifically comprises the following steps:

(1) enzymatic serine conversion: soaking real silk fiber in a tyrosine phenol lyase and a phenol solution to catalyze the conversion of serine in the real silk fiber into tyrosine; washing with water; drying;

(2) Enzymatic real silk and aniline graft polymerization: dipping the real silk fabric treated in the step (1) in an aniline monomer solution, adding laccase, and catalyzing the reaction of the leucine and aniline free radicals in the real silk fiber; washing with water; and (5) drying.

in the step (1), the formula of the tyrosine phenol lyase and the phenol solution is as follows: 10-100U/mL of tyrosine phenol lyase, 1-10 g/L of phenol, 0.5-5 g/L of pyridoxal phosphate, 0.5-2 g/L of ammonium chloride and pH of 6-8.

In the step (1), the reaction conditions are as follows: the temperature is 30-50 ℃, the time is 12-24 hours, and the bath ratio is 1: 40.

in the step (1), the water washing is carried out for 5-10 minutes in deionized water at 40-50 ℃, and the drying is carried out at 50-60 ℃.

in the step (2), the aniline concentration in the aniline monomer-containing solution is as follows: 1-4 g/L, pH 4-5.5 of aniline, and the laccase addition amount is as follows: 0.2 to 1U/mL.

in the step (2), the reaction conditions are as follows: the temperature is 30-45 ℃, the treatment time is 12-48 hours, and the bath ratio is 1: 40.

in the step (2), the water washing is carried out for 5-10 minutes in deionized water at 40-50 ℃, and the drying is carried out at 50-60 ℃.

the silk fiber prepared by the preparation method of the conductive silk based on enzymatic conversion and catalytic oxidation is within the protection scope of the invention.

Has the advantages that:

Compared with the traditional method for preparing the conductive real silk by a metal spraying method, a coating method and a padding and baking method, the method has the following advantages:

(1) The production energy consumption is low, the serine in the enzymatic real silk fiber macromolecules is converted, the enzymatic oxidation real silk and the aniline are subjected to graft polymerization, the reaction is carried out under the low-temperature mild condition, and the production energy consumption is low;

(2) The conductive effect is improved, after the enzymatic real silk fibers and aniline are subjected to free radical graft polymerization, formed polyaniline macromolecules are connected with the real silk fibers through covalent bonds, the real silk resistance is obviously reduced, and the conductive effect is durable;

(3) The strength of the fiber is increased, the conditions of enzymatic conversion and catalytic oxidation treatment are mild, the fiber damage easily generated in the traditional processing is avoided, and the laccase catalytic oxidation of tyrosine can initiate the intermolecular crosslinking of silk fibroin to promote the strength increase of the silk fiber.

Detailed Description

The technical solutions of the present invention are further described in detail by the following specific examples, but it should be noted that the following examples are only used for describing the content of the present invention and should not be construed as limiting the scope of the present invention.

A method for preparing conductive real silk based on enzymatic conversion and catalytic oxidation is characterized in that serine in real silk fibers is converted into tyrosine by using a tyrosine phenol lyase, the tyrosine in the real silk fibers is catalyzed by laccase to react with free radicals of aniline, and polyaniline macromolecules are formed by graft polymerization of the real silk and the aniline, so that the method for preparing the conductive real silk is realized. The specific embodiment is as follows: