Modified beta-CD microcapsule as well as preparation method and application thereof

Abstract

The invention discloses a modified beta-CD (cyclodextrin) microcapsule as well as a preparation method and application thereof. S-triazine is used for modifying beta-cyclodextrin. The preparation method comprises the following steps: firstly, adding DMSO and beta-cyclodextrin into a glass reaction container, dissolving a certain amount of trichlorotriazine into acetone, then adding into the glass reaction container, reacting at 60 DEG C for 8 hours, and washing and drying to obtain a product. Secondly, completely dissolving the wall material powder in deionized water at the temperature of 70 DEG C, and dropwise adding an auxiliary agent needing to be embedded into the solution; and putting the stirred emulsion into a homogenizer, and standing for 20 minutes at the pressure of 500 bar. And finally, microencapsulating the emulsion by using a spray dryer to obtain a target product. The invention aims to provide a carrier for adding the functional additive into the stock solution, the functional additive is safely added into the lyocell fiber, and the influence of the functional additive on an NMMO recovery system is greatly reduced or even eliminated.

Description

Technical Field

[0001] The invention relates to the technical field of chemical product preparation, in particular to a modified beta-CD microcapsule and a preparation method and application thereof. Background Art

[0002] Lyocell fiber is a cellulose fiber made from natural cellulose, which is directly dissolved in organic solvent NMMO and then prepared by spinning. The supramolecular structure of Lyocell fiber shows obvious fibrils, and its crystallinity is as high as 53.26%, which is higher than ordinary viscose fiber (crystallinity of about 30%) and high wet modulus viscose fiber (crystallinity of about 44%). The high degree of polymerization and high crystallinity of Lyocell fiber give it better physical and mechanical properties than other regenerated cellulose fibers, such as high dry and wet strength, high wet modulus, and small dry and wet strength difference.

[0003] Lyocell fabric is made of natural plant fibers and has environmental protection functions that viscose fibers do not have. The traditional viscose fiber remanufacturing process will release harmful gases such as sulfur dioxide and hydrogen sulfide, which are harmful to the human body and pollute the environment. Lyocell fabric not only has the comfort, good feel, and easy dyeing characteristics of cotton, but also has the luxury of wool fabric and the drape of modal. The bright surface is very suitable for making high-end clothing.

[0004] At present, due to the key cost issue of solvent recovery in the production process, it is difficult to directly add functional additives during the preparation of Lyocell fiber stock solution, and post-treatment processes are mostly used for functional surface modification. Although the post-treatment process avoids contamination of the NMMO system, it will have a significant impact on the surface of the Lyocell yarn, making the fiber surface rough and stiff, losing the physical performance advantages of Lyocell itself, and seriously reducing its market competitiveness; and the post-treatment process can only perform surface modification, and the performance of the additives will be significantly reduced by the number of times the fabric is washed, while there is no such problem in the addition of stock solution.

[0005] Therefore, it becomes crucial to provide a carrier for adding functional additives to the stock solution, safely add the functional additives to Lyocell fibers, and significantly reduce or even eliminate the impact of the functional additives on the NMMO recovery system. Summary of the invention

[0006] The purpose of the present invention is to provide a modified β-CD microcapsule and a preparation method and application thereof, aiming to provide a carrier for adding functional additives to the stock solution, and safely add the functional additives to lyocell fibers.

[0007] In order to solve the above technical problems, the present invention provides the following technical solution, a method for preparing modified β-CD microcapsules, the steps of which include:

[0008] The trichloro-s-triazine was fully dissolved in acetone and then added to a glass reaction vessel containing DMSO and β-cyclodextrin, and then stirred at 60°C to 105°C for 8 to 10 hours, and then filtered, washed with deionized water, and freeze-dried to obtain a microcapsule wall material;

[0009] A solution in which the microcapsule wall material is completely dissolved in deionized water and a solution of the functional additive dissolved in anhydrous ethanol are added into a homogenizer and treated at a pressure of 500 bar for 20 minutes to obtain a homogenous emulsion;

[0010] The homogeneous emulsion was microencapsulated by a spray dryer to obtain modified β-CD microcapsules.

[0011] Preferably, the mass ratio of the DMSO to the β-cyclodextrin is 6-8:15-20.

[0012] Preferably, the mass ratio of the acetone to the trichloro-s-triazine is 3-5:1-2.

[0013] Preferably, the microcapsule wall material is obtained after freeze-drying for 6 to 8 hours.

[0014] Preferably, the microcapsule wall material is completely dissolved in deionized water at 70°C.

[0015] Preferably, the mass ratio of the microcapsule wall material to the functional additive is 5:2.

[0016] Preferably, the homogenized emulsion is added into a spray dryer and subjected to liquid microencapsulation treatment at an air volume of 80% and an inlet air temperature of 180° C. to obtain the modified β-CD microcapsules.

[0017] In a second aspect, the present invention provides a modified β-CD microcapsule prepared by the modified β-CD microcapsule preparation method.

[0018] In the third aspect, the modified β-CD microcapsules prepared by the preparation method are used to prepare lyocell fibers.

[0019] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention provides a carrier for adding functional additives to the stock solution, safely adding the functional additives to the lyocell fiber, greatly reducing or even eliminating the impact of the functional additives on the NMMO recovery system. The β-CD microcapsules themselves are non-toxic and harmless, and the production process is green and environmentally friendly without causing environmental pollution. After modification, they can adapt to the temperature and pressure environment of the lyocell fiber production system, ensure that the core material is not damaged, avoid affecting the physical and chemical properties of the lyocell stock solution, and can be directly used for stock solution addition. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 It is a flow chart of the steps of a method for preparing modified β-CD microcapsules of the present invention;

[0022] Figure 2 It is a comparison chart of TG curves of modified β-CD wall material and unmodified β-CD wall material. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Example 1

[0025] In a 200mL three-necked flask, add 19.5g of β-cyclodextrin and 45g of DMSO. Dissolve 3g of trichloro-s-triazine in 8g of acetone and put it into the three-necked flask. Set up a reflux device. Heat and stir in a 105℃ oil bath under a nitrogen atmosphere for 8.5 hours. After cooling, filter under reduced pressure and wash with 200mL of deionized water. After freeze drying for 8 hours, obtain 18.4g of light yellow powdery microcapsule wall material.

[0026] Take 15 g of microcapsule wall material and completely dissolve it in deionized water, dissolve 4 g of lavender essential oil in 4 ml of anhydrous ethanol, add the mixture into a small homogenizer and homogenize at a pressure of 500 bar for 20 minutes to obtain a homogenous emulsion.

[0027] The homogenized emulsion was added into a spray dryer and subjected to microencapsulation treatment at an air volume of 80% and an inlet air temperature of 180° C. to obtain 18.8 g of finished microcapsules.

[0028] Example 2

[0029] In a 2L glass reactor, add 193.2g of β-cyclodextrin and 550g of DMSO, dissolve 30g of trichloro-s-triazine in 85g of acetone and put into a three-necked flask, set up a reflux device, and heat and stir in an oil bath at 105°C for 8 hours under a nitrogen atmosphere. After cooling, filter under reduced pressure and wash with 2L of deionized water. After freeze drying for 8 hours, 219.3g of microcapsule wall material in a light yellow powder form was obtained.

[0030] 150 g of microcapsule wall material was completely dissolved in deionized water, 40 g of lavender essential oil was dissolved in 40 ml of anhydrous ethanol, and the mixture was added to a homogenizer and homogenized at a pressure of 500 bar for 20 minutes to obtain a homogenous emulsion.

[0031] The homogenized emulsion was added into a spray dryer and subjected to microencapsulation treatment at an air volume of 80% and an inlet air temperature of 180° C. to obtain 184.5 g of finished microcapsules.

[0032] Comparative Example 1

[0033] The modified β-CD wall material prepared by the method of Example 1 and the unmodified β-CD wall material were subjected to thermogravimetric analysis (TG) to obtain a comparison chart of the TG curves of the modified β-CD wall material and the unmodified β-CD wall material ( Figure 2 ).

[0034] from Figure 2 It can be seen that the modified β-CD wall material has better thermal stability than the unmodified β-CD wall material.

[0035] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing modified β-CD microcapsules, characterized in that: The modified β-CD microcapsule preparation method comprises the following steps: The trichloro-s-triazine was fully dissolved in acetone and then added to a glass reaction vessel containing DMSO and β-cyclodextrin, and then stirred at 60°C to 105°C for 8 to 10 hours, and then filtered, washed with deionized water, and freeze-dried to obtain a microcapsule wall material; A solution in which the microcapsule wall material is completely dissolved in deionized water and a solution of the functional additive dissolved in anhydrous ethanol are added into a homogenizer and treated at a pressure of 500 bar for 20 minutes to obtain a homogenous emulsion; The homogeneous emulsion was microencapsulated by a spray dryer to obtain modified β-CD microcapsules.

2. The method for preparing modified β-CD microcapsules according to claim 1, characterized in that: The mass ratio of the DMSO to the β-cyclodextrin is 6-8:15-20.

3. The method for preparing modified β-CD microcapsules according to claim 1, characterized in that: The mass ratio of the acetone to the trichloro-s-triazine is 3-5:1-2.

4. The method for preparing modified β-CD microcapsules according to claim 1, characterized in that: The microcapsule wall material needs to be freeze-dried for 6 to 8 hours before it can be obtained.

5. The method for preparing modified β-CD microcapsules according to claim 1, characterized in that: The microcapsule wall material is completely dissolved in deionized water at 70°C.

6. The method for preparing modified β-CD microcapsules according to claim 1, characterized in that: The mass ratio of the microcapsule wall material to the functional additive is 5:

2.

7. The method for preparing modified β-CD microcapsules according to claim 1, characterized in that: The homogenized emulsion is added into a spray dryer, and subjected to liquid microencapsulation treatment at an air volume of 80% and an inlet air temperature of 180° C. to obtain the modified β-CD microcapsules.

8. A modified β-CD microcapsule, characterized in that: The modified β-CD microcapsules are prepared according to the method for preparing the modified β-CD microcapsules according to any one of claims 1 to 7.

9. A modified β-CD microcapsule according to any one of claims 1 to 7, characterized in that: Used in the preparation of lyocell fibers.

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