CN104404774B - The synthesis of a kind of microcapsule multifunction finishing agent based on layer upon layer electrostatic self assembly and technique for applying - Google Patents

Abstract

A synthesis and application process of a microcapsule multifunctional finishing agent based on layer-by-layer electrostatic self-assembly, which belongs to the application technology field of dyeing and finishing in the cotton and wool textile industry, and aims to use the layer-by-layer electrostatic self-assembly technology to prepare nano-TiO ₂ as the center. Microcapsule composite finishing agent, and finish it on cotton and wool fabrics through electrostatic self-assembly, so as to improve the anti-ultraviolet and antibacterial properties of the fabrics. Using the present invention can avoid the cumbersome steps of single anti-ultraviolet finishing and single antibacterial finishing, shorten the technological process, save costs, improve the action efficiency of nano- _TiO2 , and greatly improve the anti-ultraviolet performance of cotton and wool fabrics. antibacterial effect.

Description

Synthesis and application process of a microcapsule multifunctional finishing agent based on layer-by-layer electrostatic self-assembly

technical field

The invention discloses a synthesis and application process of a microcapsule multifunctional finishing agent based on layer-by-layer electrostatic self-assembly, which belongs to the application technical field of dyeing and finishing in the cotton and wool textile industries.

Background technique

The principle of preparing microcapsules based on Layer-by-Layer Self-assembly Technique (LBL) is to use the electrostatic attraction between specific polymer compounds to spontaneously separate positively and negatively charged substances through electrostatic attraction. A technique in which layers are alternately deposited on the surface of a template material and associate to form molecular aggregates with complete structure and stable performance. The technical process of this kind of microcapsule construction is simple, no complicated equipment is required, and the composition thickness of the capsule wall can be adjusted. Latex particles, inorganic particles, organic particles, enzymes and red blood cells are often used as template materials, and the capsule wall is generally a polymer compound. .

Microencapsulation technology is an important means of multifunctional finishing in the textile industry. The reason why it is widely used as a means of preparing intelligent and functional textiles is that microencapsulation of specific substances can achieve many purposes, such as active ingredients Controlled release, so that the drug has a targeted function, releases the drug and fragrance regularly; adjusts the microclimate in the human clothing through the heat absorption and release of the phase change material to maintain a comfortable feeling; the heat-sensitive or photosensitive discoloration of the color-changing material provides decorative or protective colors , Correspondingly produce slow-release smart textiles, smart temperature-regulating textiles and smart color-changing textiles. At present, the application of microcapsule technology in textiles mainly focuses on printing, dyeing and functional finishing, including electrostatic dyeing, transfer printing, three-dimensional foam printing, heat-sensitive color-changing printing, aromatic finishing, flame-retardant finishing, antibacterial and deodorant finishing, etc. . For example, microencapsulation of essence can improve the quality of aroma finishing and prolong the release time of fragrance; using antibacterial microcapsules in textile finishing can obtain highly efficient, washable and safe antibacterial textiles; finishing insect repellent microcapsules into fabrics In addition, it can effectively solve the problem of insect bites, and the insect repellent effect lasts for a long time.

Finishing textiles with microcapsule technology can improve the comfort and functionality of textiles, but there are not many examples of commercial success. Since the fabric must be wash-resistant, the microencapsulated finish needs to form a strong bond with the treated fibers. At present, adhesives and coating agents are mostly used for mechanical fixation, which has the disadvantages of poor fabric hand feeling and decreased functional effect.

According to the characteristic that the surface of wool fiber and cotton fiber has a certain charge under specific pH conditions, the invention establishes a microcapsule multifunctional finishing agent synthesis technology and a fabric finishing technology based on an electrostatic self-assembly method. Firstly, nano-TiO ₂ particles are used as the core material, and polystyrene sulfonate sodium (PSS) and polycationic polyhexamethylene biguanide hydrochloride (PHMB) are used as the wall materials to make microcapsules through layer-by-layer electrostatic assembly; then The fabric with the opposite charge on the surface is immersed in the treatment bath of microcapsule finishing agent, under the action of electrostatic driving force, the microcapsules with charge on the surface can be adsorbed to the surface of the fabric with opposite charge on the surface, so that the assembled microcapsules can be finished to on the fabric. Based on the antibacterial and anti-ultraviolet effects of nano- _TiO2 and the excellent antibacterial properties of PHMB, the microcapsules made by assembling PHMB on the surface of nano- _TiO2 not only have anti-ultraviolet function, but also have greatly improved antibacterial properties. By combining the surface-charged microcapsules on cotton and wool fabrics through electrostatic self-assembly, not only can endow the fabrics with anti-ultraviolet function, but also achieve an ideal double antibacterial effect.

Contents of the invention

The purpose of the present invention is to utilize the layer-by-layer electrostatic self-assembly technology to prepare the microcapsule composite finishing agent centered on nano- _TiO2 , and to arrange it on cotton and wool fabrics through electrostatic self-assembly, so as to improve the anti-ultraviolet and antibacterial properties of the fabrics . Compared with the mechanical fixation method of adhesives and coating agents, the combination of microcapsules with cotton and wool fabrics through electrostatic force is more conducive to exerting their functional properties and minimizing the impact on the physical and mechanical properties of the fabrics. Using the present invention can also overcome the shortcomings of anti-ultraviolet finishing agent and antibacterial finishing agent in the one-bath finishing of the finishing agent compatibility requirements, and the finishing effect is not as good as single finishing, shorten the technological process, save costs, and improve the effect of nano- _TiO Efficiency, while improving the anti-ultraviolet properties of cotton and wool fabrics, it also greatly improves the antibacterial effect of the fabrics.

Technical scheme of the present invention: a kind of synthesis and application process of microcapsule multifunctional finishing agent based on layer-by-layer electrostatic self-assembly, characterized in that excessive polyhexamethylene biguanide hydrochloride (PHMB) is added to the _TiO2 particle suspension ) solution, using electrostatic mutual attraction to make the surface of _TiO2 particles adsorb a layer of polyelectrolyte layer with opposite charges, centrifuging and washing to remove excess PHMB to obtain two-layer microcapsules (TiO2 is the first layer). Then excessive polystyrene sulfonate sodium (PSS) solution is added in the above-mentioned microcapsule solution, due to electrostatic adsorption, PSS is adsorbed on the surface of the positively charged microcapsules, and the excessive PSS is removed by repeated centrifugation and washing to obtain the assembled three layer of microcapsules. Repeat the above process to alternately adsorb polyelectrolytes on the surface of _TiO2 particles to form a multilayer film. Microcapsules with different charges can be obtained by controlling the types of the outermost assembly motifs of the microcapsules. Finally, the microcapsule finishing agent is finished on the pre-treated cotton or wool fabric with the opposite charge to the microcapsule finishing agent by electrostatic adsorption, so as to endow the fabric with antibacterial and anti-ultraviolet functions.

Its technological process is:

Microcapsule preparation process: prepare _TiO2 solution→add polyhexamethylene biguanide hydrochloride→centrifuge→dissolve the precipitate and pulverize→add sodium polystyrene sulfonate→centrifuge→dissolve the precipitate and pulverize→repeatedly add polyhexamethylene Biguanide Hydrochloride and Sodium Polystyrene Sulfonate.

Fabric finishing process: cotton and wool fabric pretreatment → impregnated with microcapsule finishing agent → drying

(1) Preparation of TiO ₂ microcapsule self-assembly layer: Prepare 1-2.50g/mL TiO ₂ solution, adjust the pH to 9.0, add a dispersant with a TiO ₂ mass fraction of 5-25%, and pulverize in an ultrasonic cell pulverizer 5min. Add 100mL of 10-35g/L polyhexamethylene biguanide hydrochloride solution to the above _TiO2 solution, mix and react for 2min, centrifuge, dissolve the precipitate in deionized water, pulverize in an ultrasonic cell pulverizer, and the microcapsules The surface is positively charged. Add 15 mL of 10-35 g/L sodium polystyrene sulfonate solution to the above solution, mix and react for 2 minutes, centrifuge, take the precipitate, dissolve it in deionized water, and pulverize it in an ultrasonic cell pulverizer. At this time, the surface of the microcapsules is negatively charged. Repeat the above process in turn until microcapsules with a certain size are obtained. The surface of the microcapsules prepared by this method can be positively charged (the outermost layer is PHMB) or negatively charged (PSS).

(2) Cotton and wool fabric pretreatment: soak the wool fabric in a hydrochloric acid solution with a pH of 1 for 10-30 minutes, and set aside. The isoelectric point of wool is 4.2-4.8, and the surface of the wool fabric is positively charged at pH=1; soak the cotton fabric in deionized water for 10-30 minutes for later use, because the cellulose macromolecule contains several hydroxyl groups, the cotton fabric is immersed in the aqueous solution The dissociation of hydroxyl groups makes the surface of the fabric negatively charged.

(3) Treatment of microcapsules to fabric: immerse the treated wool fabric with positively charged surface into the microcapsule solution with negatively charged surface, and make the microcapsules adsorb to the surface of the fabric by electrostatic adsorption, and then dry it at 105°C drying in an oven; immersing the treated cotton fabric with a negatively charged surface into a solution of microcapsules with a positively charged surface, drying it in an oven at 105°C after drying.

(4) In the present invention, other antibacterial polycations can also be used instead of PHMB.

Beneficial effects of the present invention: the synthesis and application process of a microcapsule multifunctional finishing agent based on layer-by-layer electrostatic self-assembly of the present invention can avoid the cumbersome steps of single anti-ultraviolet finishing and single antibacterial finishing, and shorten the process flow. It saves cost, improves the action efficiency of nano-TiO ₂ , and greatly improves the antibacterial effect of the fabric while improving the anti-ultraviolet performance of cotton and wool fabrics.

detailed description

Example 1

Sample type: wool fabric

(1) Immerse the woolen fabric in a hydrochloric acid solution with a pH of 1 for 30 minutes, and set aside for later use. At this time, the surface of the woolen fabric is positively charged.

(2) Prepare the microcapsules whose outermost layer is PSS and whose surface is negatively charged. The specific steps are as follows: prepare 1.50 g/mL TiO ₂ solution, adjust the pH to 9.0, add a dispersant with a mass fraction of TiO ₂ of 20%, and pulverize in an ultrasonic cell pulverizer for 5 min. Add 100 mL of polyhexamethylene biguanide hydrochloride (35 g/L) solution to the above _TiO2 solution, mix and react for 2 min, centrifuge, dissolve the precipitate in deionized water, and pulverize in an ultrasonic cell pulverizer (at this time, the microcapsules positively charged surface). Take 15mL of sodium polystyrene sulfonate (35g/L) solution and add it to the above solution, mix and react for 2min, centrifuge, take the precipitate and dissolve it in deionized water, and pulverize it in an ultrasonic cell pulverizer. At this time, the surface of the microcapsules is negatively charged. . Repeat the above process 8 times in turn until microcapsules with a certain size are obtained. Finally, the outermost layer of the microcapsule prepared by this method is controlled to be PSS, that is, the surface of the fiber is negatively charged.

(3) Immerse the woolen fabric in the microcapsule solution for 20 minutes, dry it in an oven at 105°C after drying.

After the above-mentioned finishing of the wool fabric, after testing, its ultraviolet protection factor (UPF) reaches 250, and the antibacterial rate of the wool fabric treated under this condition reaches 98.9%.

Example 2

Sample type: cotton fabric

(1) Soak the cotton fabric in deionized water for 30 minutes, and set it aside, at this time, the surface of the cotton fabric is negatively charged.

(2) Prepare microcapsules whose outermost layer is PHMB and whose surface is positively charged. The specific steps are as follows: prepare 2.50 g/mL TiO ₂ solution, adjust the pH to 9.0, add a dispersant with a mass fraction of TiO ₂ of 25%, and pulverize in an ultrasonic cell pulverizer for 5 min. Add 100 mL of polyhexamethylene biguanide hydrochloride (35 g/L) solution to the above _TiO2 solution, mix and react for 2 min, centrifuge, dissolve the precipitate in deionized water, and pulverize in an ultrasonic cell pulverizer (at this time, the microcapsules positively charged surface). Take 15mL of sodium polystyrene sulfonate (35g/L) solution and add it to the above solution, mix and react for 2min, centrifuge, take the precipitate and dissolve it in deionized water, and pulverize it in an ultrasonic cell pulverizer. At this time, the surface of the microcapsules is negatively charged. . Repeat the above process 10 times in turn until microcapsules with a certain size are obtained. Finally, the outermost layer of the microcapsule prepared by this method is controlled to be PHMB, that is, the surface of the fiber is positively charged.

(3) Immerse the cotton fabric in the microcapsule solution for 10 minutes, dry it in an oven at 105°C after airing.

After testing, the cotton fabric treated above has an ultraviolet protection factor (UPF) of 64.55 and a bacteriostasis rate of 98.1%.

Claims (3)

1. microcapsule multifunction finishing agent based on a layer upon layer electrostatic self assembly synthesis and application Technique, is characterized in that at TiO₂Particle suspension liquid adds the cosmocil stearate of excess Acid salt solution, utilizes electrostatic adelphotaxy, makes TiO₂Microparticle surfaces one layer of band phase of absorption The polyelectrolyte layer of counter charges；Again the kayexalate solution of excess is added above-mentioned micro-glue In capsule solution, due to electrostatic adsorption, PSS is adsorbed onto the surface of microcapsule of positively charged；Weight Multiple said process, makes polyelectrolyte at TiO₂Microparticle surfaces alternating sorbent, forms multilayer film, Prepare microcapsule dressing agent；Finally, by Electrostatic Absorption, microcapsule dressing agent is arranged respectively On cotton that anticipated, oppositely charged, wool fabric；

(1)TiO₂The preparation of microcapsule Iy self-assembled layer: preparation 1-2.50g/mL TiO₂Solution, Regulation pH is 9.0, adds TiO₂Mass fraction is the dispersant of 5-25%, thin at ultrasound wave Born of the same parents' pulverizer is pulverized 5min；To above-mentioned TiO₂Solution adds poly-six methylenes of 10-35g/L Base biguanide hydrochloride solution 100mL, hybrid reaction 2min, centrifugal, precipitation is dissolved in from In sub-water, pulverize in ultrasonic cell disruptor, now surface of microcapsule positively charged；Take again 15mL10-35g/L kayexalate solution joins in above-mentioned solution, hybrid reaction 2 Min, centrifugal, take precipitation and be dissolved in deionized water, pulverize in ultrasonic cell disruptor； It is repeated in said process 5-20 time, obtains the microcapsule with certain size；

(2) pretreatment cotton, woolen: by wool fabric in the hydrochloric acid solution that pH is 1 Dipping 10-30min, standby；Bafta is soaked 10-30min in deionized water, standby；

(3) microcapsule process to fabric: the wool fabric of surface positively charged that will process It is immersed in the electronegative microcapsule solution in surface, makes microcapsule adsorb by Electrostatic Absorption mode To fabric face, dry in 105 DEG C of baking ovens after drying；By electronegative for the surface that processed Bafta be immersed in the microcapsule solution of surface positively charged, at 105 DEG C of baking ovens after drying Middle drying.

A kind of microcapsule based on layer upon layer electrostatic self assembly the most according to claim 1 is many Functional finishing agent synthesis and technique for applying, it is adaptable to process bafta and wool fabric；Pilus Caprae seu Ovis is knitted Thing include four kinds of worsted fabrics such as all-wool gabardine, serge, valitin, female's clothing and Various drap-de-berry fabrics.

A kind of microcapsule based on layer upon layer electrostatic self assembly the most according to claim 1 is many Functional finishing agent synthesis and technique for applying, is characterized in that the hexamethylene of application Also can be selected for other polycations having anti-microbial property to substitute.