阅读说明：本技术 一种双亲两性多肽基聚合物、制备方法及应用 (Amphiphilic amphoteric polypeptide-based polymer, preparation method and application ) 是由 王学川 孙思薇 朱兴 雷萌 黄良莹 李靖 于 2020-05-29 设计创作，主要内容包括：一种双亲两性多肽基聚合物的制备与应用方法,采用制革废皮屑中提取的胶原多肽为原材料,通过长链烷基缩水甘油醚对其接枝改性,合成出具有表面活性的两性多肽基聚合物,之后将其应用于有机无铬生态鞣皮革加脂工序。本发明制得的双亲两性多肽基聚合物,可应用在有机无铬生态鞣制革加脂工序,增加制革化学品的吸收率,成品革的柔软性和丰满性,本发明选用制革废弃皮胶原为原材料,对制革废弃物进行了再利用,变废为宝,同时选用的胶原多肽为生物质再生资源,无刺激性,生物降性优异,符合环保、绿色、可持续发展的理念。(A preparation and application method of an amphiphilic amphoteric polypeptide-based polymer is characterized in that collagen polypeptide extracted from leather waste is used as a raw material, the collagen polypeptide is subjected to graft modification by long-chain alkyl glycidyl ether to synthesize the amphoteric polypeptide-based polymer with surface activity, and then the amphoteric polypeptide-based polymer is applied to an organic chromium-free ecological tanning leather greasing process. The amphiphilic amphoteric polypeptide-based polymer prepared by the method can be applied to an organic chromium-free ecological tanning greasing process, the absorption rate of tanning chemicals is increased, and the softness and fullness of finished leather are improved.)

1. A preparation method of an amphiphilic polypeptide-based polymer is characterized by comprising the following steps:

reacting primary amine groups in the collagen polypeptide containing the primary amine groups and carboxyl groups with epoxy groups in long-chain alkyl glycidyl ether, wherein the molar ratio of the primary amine groups to the epoxy groups is 1: (0.8-1.2) to obtain the amphiphilic amphoteric polypeptidyl polymer.

2. The method of claim 1, wherein the long chain alkyl glycidyl ether is one or more of decyl glycidyl ether, dodecyl glycidyl ether, tetradecyl glycidyl ether, dodecyl to tetradecyl glycidyl ether, hexadecyl glycidyl ether, octadecyl glycidyl ether, and eicosyl glycidyl ether.

3. The method of claim 1, comprising the steps of:

dropwise adding a mixture of long-chain alkyl glycidyl ether and an organic solvent into an aqueous solution of collagen polypeptide, wherein the mass of water is 80-150% of the mass of the collagen polypeptide, the pH range of the system is 8-11, uniformly mixing, stirring at 40-80 ℃ for reacting for 6-16 h, and purifying after the reaction is finished to obtain the amphiphilic amphoteric polypeptide-based polymer.

4. The method of claim 3, wherein the organic solvent is one or more of methanol, isopropanol, n-propanol; the mass ratio of the solvent to the water is 1: 1.

5. The method of claim 3, wherein the purification process performed after completion of the reaction comprises the steps of: after the reaction is finished, removing the reaction solvent by rotary evaporation at 40-80 ℃, washing the product by using a mixed solution of ethanol and dichloromethane, removing unreacted alkyl glycidyl ether and collagen polypeptide, and finally drying in vacuum at 40-60 ℃ to obtain the amphiphilic amphoteric polypeptide-based polymer.

6. An amphiphilic polypeptidyl polymer obtainable by the method of any one of claims 1 to 5.

7. Use of the amphiphilic amphiphatic polypeptidyl polymer according to claim 6 in an organic chrome-free tanning leather fatliquoring process.

8. The use according to claim 7, wherein the amphiphilic polypeptidyl polymer is used in an organic chrome-free tanned leather fatliquoring process after being compounded with a grease.

9. Use according to claim 8, wherein the organic chrome-free tanning leather fatliquoring process comprises the following steps: uniformly shaving and weighing the wet white leather, and neutralizing until the pH value is 5.5-6.0 after retanning in a rotary drum; and then adding a compound of amphiphilic amphoteric polypeptidyl polymer and grease with the mass fraction of wet white leather being 10-20%, wherein the liquid ratio is 1:1, transferring the mixture in a rotary drum for 2-4 hours at 50-60 ℃, and then adjusting the pH value to 3.5-4.5.

10. A composition for use in an organic chrome-free tanning leather fatliquoring process, comprising a grease and the amphiphilic amphoteric polypeptidyl polymer of claim 7; the oil is one or more of castor oil, neatsfoot oil, lanolin, and lecithin.

Technical Field

The invention belongs to the technical field of modified collagen polypeptide and chrome-free tanning leather, and particularly relates to preparation and application of an amphiphilic amphoteric polypeptide-based polymer.

Background

In recent years, the trend of chrome-free eco-tanning to replace chrome tanning has been gradually emerging. The production of the chromium-free ecological tanning mainly comprises the production process of wet white leather, retanning, fatliquoring and dyeing matched chemicals and process and the readjustment of a finishing process by utilizing the ecological organic tanning agent. The organic chromium-free tanning method can reduce the positive charge of a leather blank, and the isoelectric point of the leather blank is lower than that of chromium-tanned leather, so that most anionic compounds matched in the traditional chromium-tanned leather-making system have reduced binding fastness and low absorption rate, the quality of finished leather is influenced, and the development requirement of the organic chromium-free tanning system cannot be met. Compared with anionic compounds, the amphoteric compounds contain anions and cations simultaneously, can regulate and control the surface charge of crust leather, and are beneficial to the reaction matching property of the whole wet finishing material of the chrome-free tanned leather, so that the amphoteric compounds become the main structure of the matched chemicals of an organic chrome-free tanned system. Among them, the amino acid type amphoteric compound has been a hot point of research on tanning chemicals due to its wide source, low irritation and good biodegradability.

Disclosure of Invention

In order to solve the problems in the prior art, the invention aims to provide a preparation method of an amphiphilic amphoteric polypeptide-based polymer and an application method of the amphiphilic amphoteric polypeptide-based polymer in an organic chrome-free tanning and fat-liquoring process, the method is simple to operate and high in yield, the synthesized amphiphilic amphoteric polypeptide-based polymer has excellent surface activity and proper isoelectric point, the variety of chemicals matched with chrome-free tanning leather can be increased, the softness and fullness of the chrome-free tanning leather are improved, and the amphiphilic polypeptide-based polymer is firmly combined with chrome-free tanning collagen fibers.

In order to achieve the purpose, the invention adopts the technical scheme that:

the method comprises the following steps: according to the molar ratio of primary amino groups in the collagen polypeptide to epoxy groups in the long-chain alkyl glycidyl ether of 1: (0.8-1.2) weighing a certain amount of collagen polypeptide and long-chain alkyl glycidyl ether, dissolving the collagen polypeptide in water, mixing the long-chain alkyl glycidyl ether with an organic solvent, dropwise adding the mixture into a collagen polypeptide aqueous solution, uniformly mixing, heating, continuously stirring, and purifying after the reaction is finished to obtain the amphiphilic amphoteric polypeptide-based polymer.

Step two: the synthesized amphiphilic amphoteric polypeptidyl polymer is compounded with different types of grease and then applied to the greasing procedure of organic chrome-free tanned leather.

The collagen polypeptide added in the step one is extracted from leather making waste leather scraps, and the weight average molecular weight range of the collagen polypeptide is 500-5000.

The long-chain alkyl glycidyl ether added in the first step is one of decyl glycidyl ether, dodecyl glycidyl ether, tetradecyl glycidyl ether, dodecyl-tetradecyl glycidyl ether, hexadecyl glycidyl ether, octadecyl glycidyl ether and eicosyl glycidyl ether.

In the first step, the addition amount of water is 80-150% of the mass of the collagen polypeptide, the viscosity of a reaction system is mainly adjusted, and the reaction is facilitated, the organic solvent is methanol, isopropanol or n-propanol, the mass ratio of the use amount of the solvent to water is 1:1, the pH value of the system is 8-11, the reaction temperature is 40-80 ℃, and the reaction time is 6-16 h.

The purification in the first step comprises the following specific steps: after the reaction is finished, removing the reaction solvent by rotary evaporation at 40-80 ℃, washing the product by using a mixed solution of ethanol and dichloromethane, removing unreacted alkyl glycidyl ether and collagen polypeptide, and finally drying in vacuum at 40-60 ℃ to obtain the amphiphilic amphoteric polypeptide-based polymer.

The grease used in the second step is one or a mixture of at least two of castor oil, neatsfoot oil, lanolin and lecithin. The dosage of the grease is determined according to the actual application requirement.

In the second step, the compound of the amphiphilic amphoteric polypeptidyl polymer and the grease can be used as a leather fatting agent in an organic chromium-free ecological tanning leather fatting procedure, and the specific process is as follows: uniformly shaving and weighing wet white leather, neutralizing until the pH value is 5.5-6.0 after retanning in a rotary drum, adding a compound of amphiphilic amphoteric polymer and grease with the mass fraction of 10-20% of the wet white leather, wherein the liquid ratio is 1:1, transferring for 2-4 h in a rotary drum at 50-60 ℃, then adjusting the pH value to 3.5-4.5, and then operating according to the production and processing procedures of common leather products.

Compared with the prior art, the preparation and application method of the amphiphilic amphoteric polypeptide-based polymer provided by the invention adopts the long-chain alkyl glycidyl ether to modify collagen polypeptide extracted from leather-making waste leather scraps to prepare the amphiphilic amphoteric polymer, and applies the amphiphilic amphoteric polymer to the organic chromium-free ecological tanning leather greasing process. The introduced collagen polypeptide molecules contain amino and carboxyl simultaneously, so that the final product has amphoteric property, has different charges under the condition of different pH values, can be matched with organic chromium-free ecological tanning leather, and increases the absorption rate of leather chemicals. Meanwhile, the hydrophobic long chain is grafted to collagen polypeptide molecules, so that the final product has hydrophilic and oleophilic amphiphilic property and excellent surface activity, can be directly applied to a leather making and greasing process, increases the softness and fullness of finished leather and improves the quality of finished leather. And meanwhile, the selected collagen polypeptide is a biomass renewable resource, has no irritation and excellent biodegradability, and meets the requirements of leather-making chemicals on environmental protection, green and sustainable development.

Drawings

FIG. 1 is a scheme for preparing an amphiphilic amphoteric polypeptide-based polymer;

FIG. 2 is an infrared spectrum of the amphiphilic polypeptidyl polymer prepared in example 2. In contrast, in the amphoteric polypeptide-based polymer, 3100-3700 cm is found due to the generation of hydroxyl^-1Peak at 2925 cm^-1(symmetric stretching vibration) and 2856 cm^-1(asymmetric stretching vibration) is-CH₂The stretching vibration peak of C-H in-is enhanced, 911 cm^-1And 846 cm^-1The bending vibration absorption peak of the epoxy group is obviously reduced or disappeared.

FIG. 3 is a graph showing the change of potential with pH of the amphiphilic amphiphatic polypeptidyl polymer and the collagen polypeptide prepared in example 3. With the change of pH, the types and the electric charge quantity of the electric charges of the amphoteric polypeptidyl polymer and the collagen polypeptide also change, in the range of pH 2-10, with the increase of pH, the electric charge type of the tested amphoteric polymer is changed from positive electric charge to negative electric charge, the electric charge quantity is reduced firstly and then is increased, and the isoelectric point of the amphoteric polypeptidyl polymer is 4.27.

Detailed Description

The preparation and application methods of the amphiphilic polypeptidyl polymer provided by the present invention are further described in detail below with reference to examples.