阅读说明：本技术 一种聚甲醛纤维整理剂、自修复超疏水织物及制备方法 (Polyformaldehyde fiber finishing agent, self-repairing super-hydrophobic fabric and preparation method ) 是由 王亚涛 金旺 赵涛 李洪娟 刘保江 刘莉莉 马小丰 郭学华 于 2021-08-26 设计创作，主要内容包括：本发明涉及聚甲醛功能面料技术领域,具体提供一种聚甲醛纤维整理剂、自修复超疏水织物及制备方法。所述聚甲醛纤维整理剂为星形聚合物,结构式如式(Ⅰ)所示。本发明提供的聚甲醛纤维整理剂,可在聚甲醛纤维织物中引入室温下既稳定又高度可逆的N配位硼氧六环动态共价键,能够在很大程度上弥补高强度聚合物材料链段运动能力低造成的修复和循环性能较差的问题,且结构中含有三重交联,交联密度高,可提高织物的耐久性,在制备自修复超疏水织物领域具有较高的应用推广价值。(The invention relates to the technical field of polyformaldehyde functional fabrics, and particularly provides a polyformaldehyde fiber finishing agent and a self-repairing super-hydrophobic fabricA water fabric and a preparation method thereof. The polyformaldehyde fiber finishing agent is a star polymer, and the structural formula is shown as a formula (I). The polyformaldehyde fiber finishing agent provided by the invention can introduce a stable and highly reversible N-coordinated boron-oxygen hexacyclic dynamic covalent bond at room temperature into a polyformaldehyde fiber fabric, can make up for the problem of poor repairing and circulating performance caused by low motion capability of a chain segment of a high-strength polymer material to a great extent, has a triple cross-linking structure, is high in cross-linking density, can improve the durability of the fabric, and has high application and popularization values in the field of preparing self-repairing super-hydrophobic fabrics.)

1. A polyformaldehyde fiber finishing agent is characterized in that the structure of the polyformaldehyde fiber finishing agent is a star polymer, and the structural formula is shown as a formula (I):

wherein R is n-octadecylsilyl, and n is 6-15.

2. The process for preparing a polyoxymethylene fiber finish of claim 1, comprising the steps of:

dissolving o-aldehyde phenylboronic acid, amino-terminated polypropylene glycol and octadecylsilane in an alcohol solvent, uniformly mixing, cooling to 0-4 ℃, adding an initiator, reacting for 2-4 days under a heat preservation condition, extracting, and drying to obtain the polyformaldehyde fiber finishing agent.

3. The method for producing a polyoxymethylene fiber finish of claim 2, wherein the molar ratio of the orthoformylphenylboronic acid, the amino-terminated polypropylene glycol, and the octadecylsilane is 1.5-2.5:1.5-2.5: 0.3-0.5.

4. The method for preparing a polyoxymethylene fiber finish of claim 2, wherein the initiator is at least one of sodium borohydride, potassium borohydride or ascorbic acid.

5. The method for producing a polyoxymethylene fiber finish according to claim 2 or 4, wherein the molar ratio of the initiator to the orthoformylphenylboronic acid is 1.5 to 3.5:1.5 to 2.5.

6. A method for finishing polyformaldehyde fibers is characterized by at least comprising the following steps:

step a, adding polyformaldehyde fibers into a first finishing liquid, heating, dipping and drying to obtain pretreated polyformaldehyde fibers;

the first finishing liquid comprises the following components in percentage by mass: 5-10% of polycarboxylic acid, 15001.0-1.5% of polyethylene glycol, 0.5-1.0% of sodium hypophosphite, 1.0-2.0% of metal ion complexing agent and the balance of water;

b, adding the polyformaldehyde fiber finishing agent and the nano-silica into an alcohol solvent, and uniformly dispersing to obtain a second finishing liquid;

and c, finishing the second finishing liquid on the pretreated polyformaldehyde fibers to obtain the repaired super-hydrophobic fabric.

7. The method for finishing polyoxymethylene fibers according to claim 6, wherein in the step a, the temperature of the temperature-raising impregnation is 60 ℃ to 80 ℃ and the time is 3min to 6 min; and/or

In the step a, the volume-to-mass ratio of the polyformaldehyde fiber finishing liquid to the polyformaldehyde fibers is 10-30:1, wherein the mass unit is gram, and the volume unit is milliliter.

8. The method for finishing polyoxymethylene fibers according to claim 6, wherein in step a, the metal ion complexing agent is one or two of ferric nitrate, ferric trichloride, bismuth nitrate and bismuth chloride.

9. The method for finishing polyoxymethylene fibers according to claim 6, wherein in step b, the mass ratio of the polyoxymethylene fiber finish to the nano-silica is 1:1.0 to 1.5; and/or

The particle size of the nano silicon dioxide is 5nm-10 nm.

10. A self-repairing super-hydrophobic fabric, which is obtained by the finishing method of the polyformaldehyde fibers as defined in any one of claims 6-9.

Technical Field

The invention relates to the technical field of polyformaldehyde functional fabrics, and particularly relates to a polyformaldehyde fiber finishing agent, a self-repairing super-hydrophobic fabric and a preparation method thereof.

Background

Polyoxymethylene Fiber (Polyoxymethylene Fiber) is a synthetic Fiber prepared by spinning Polyoxymethylene (POM). At present, the most common preparation method of polyoxymethylene fibers at home and abroad is a melt spinning method, and the polyoxymethylene fibers prepared by the method have the advantages of good size stability, wear resistance, solvent resistance and seawater invasion resistance, and also have excellent quick-drying and cool feeling properties.

With the improvement of living standard of people, the demand of the polyformaldehyde functional fabric with waterproof performance is increasing day by day. In the hydrophobic finishing process, the fluorine hydrophobic finishing agent has incomparable advantages in the aspects of waterproofness, oil repellency, antifouling property, rubbing resistance, washing resistance and the like, and is a main variety applied in the current market. However, the mainstream product of the fluorine-based hydrophobic finishing agent, class C8, is a fluorine-based hydrophobic finishing agent which generates two chemical substances of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid ammonium (PFOA) during synthesis and use, has high chemical stability, is difficult to degrade under natural conditions, generates biological accumulation in plants and human bodies, and threatens human health. Moreover, during the use of the superhydrophobic fabric, sunlight irradiation, air oxidation, acid rain corrosion or physical damage can cause the decomposition or consumption of the hydrophobic substance, resulting in irreversible loss of the superhydrophobic function. The self-repairing super-hydrophobic fabric can obviously improve the stability of the super-hydrophobic function of the fabric and prolong the service life of the fabric. Therefore, in recent years, the repair of superhydrophobic fabrics has become a focus of research. However, the polyformaldehyde fiber has a regular molecular structure, high cohesive energy density, high crystallinity of more than 70%, a low amorphous region proportion, no branched chain structure and a lack of active groups on the surface, so that the polyformaldehyde fiber has low chemical reactivity, the finishing agent is not easy to finish on the polyformaldehyde fiber, and the conventional fluorine hydrophobic finishing agent has the defects of potential harm to human health and easy yellowing of the finished fabric. Therefore, the novel polyformaldehyde fiber hydrophobic finishing agent is developed to construct a stable fluorine-free super-hydrophobic surface on the surface of polyformaldehyde fibers, and has very important significance for expanding the market of polyformaldehyde fibers and green clean production of textile hydrophobic finishing.

Disclosure of Invention

The invention provides a polyformaldehyde fiber finishing agent, a self-repairing super-hydrophobic fabric and a preparation method thereof, aiming at the defects that the conventional finishing agent is not easy to finish polyformaldehyde fibers, and the conventional fluorine hydrophobic finishing agent not only has the defect of potential harm to human health, but also has the problem that the finished fabric is easy to yellow.

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

a polyformaldehyde fiber finishing agent is a star polymer and has a structural formula shown as a formula (I):

wherein R is n-octadecylsilyl; n is the polymerization degree of the amino-terminated polypropylene glycol, and n is 6-15.

Compared with the prior art, the polyformaldehyde fiber finishing agent provided by the invention contains an N-coordinated boron-oxygen-hexacyclic structure, and the N-coordinated boron-oxygen-hexacyclic dynamic covalent bond can be reversibly opened and reestablished at room temperature and has high reversibility; in addition, the coordination N connected with the boron-oxygen hexacyclic structure can be bonded with other groups based on hydrogen bond action, so that the self-repairing function is improved; meanwhile, N connected with Si on a benzene ring in the polyformaldehyde fiber finishing agent structure can form a metal coordination bond with metal ions, and the N coordinated boron-oxygen hexacyclic dynamic covalent bond is crosslinked with the metal coordination bond, so that a hydrophobic chain segment (namely octadecyl silane group) has good chain migration capacity, and after the abrasion, when a low surface energy substance on the surface of a fabric is damaged, the hydrophobic chain segment can realize the rapid repair of a superhydrophobic function at room temperature through the migration of the crosslinking bond.

The polyformaldehyde fiber finishing agent provided by the invention can introduce a dynamic covalent bond which is stable and highly reversible at room temperature into a polyformaldehyde fabric, can make up for the problem of poor repairing and circulating performance caused by low motion capability of a chain segment of a high-strength polymer material to a great extent, has triple cross-linking in the structure, has high cross-linking density, can improve the durability of the fabric, and has high application and popularization values in the field of preparing self-repairing super-hydrophobic fabrics.

The invention also provides a preparation method of the polyformaldehyde fiber finishing agent, which comprises the following steps:

dissolving o-aldehyde phenylboronic acid, amino-terminated polypropylene glycol and octadecylsilane in an alcohol solvent, uniformly mixing, cooling to 0-4 ℃, adding an initiator, reacting for 2-4 days under a heat preservation condition, extracting, and drying to obtain the polyformaldehyde fiber finishing agent.

Firstly, o-aldehyde phenylboronic acid and amino-terminated polypropylene glycol are subjected to reductive amination reaction to obtain an intermediate 1; the intermediate 1 is subjected to dehydration condensation reaction to obtain an intermediate 2; and hydrolyzing the octadecylchlorosilane, and then carrying out substitution reaction with the intermediate 2 to obtain the polyformaldehyde fiber finishing agent. The specific reaction process is schematically shown as follows:

the curved part in the above schematic representation

Preferably, the molar ratio of the o-aldenylbenzoic acid to the amino-terminated polypropylene glycol to the octadecylsilane is 1.5-2.5:1.5-2.5: 0.3-0.5.

Preferably, the alcohol solvent is absolute ethyl alcohol.

Further preferably, the volume molar ratio of the alcohol solvent to the o-aldehyde phenylboronic acid is 5-10: 1.5-2.5, wherein the volume unit is milliliter.

Preferably, the initiator is at least one of sodium borohydride, potassium borohydride or ascorbic acid.

Preferably, the molar ratio of the initiator to the o-aldehyde phenylboronic acid is 1.5-3.5: 1.5-2.5.

Preferably, the reaction conditions are favorable for improving the yield and the purity of the polyformaldehyde fiber finishing agent with the structure shown in the formula (I).

The invention also provides a finishing method of the polyformaldehyde fibers, which at least comprises the following steps:

step a, adding polyformaldehyde fibers into a first finishing liquid, heating, dipping and drying to obtain pretreated polyformaldehyde fibers;

the first finishing liquid comprises the following components in percentage by mass: 5-10% of polycarboxylic acid, 15001.0-1.5% of polyethylene glycol, 0.5-1.0% of sodium hypophosphite, 1.0-2.0% of metal ion complexing agent and the balance of water;

b, adding the polyformaldehyde fiber finishing agent and the nano-silica into an alcohol solvent, and uniformly dispersing to obtain a second finishing liquid;

and c, finishing the second finishing liquid on the pretreated polyformaldehyde fibers to obtain the repaired super-hydrophobic fabric.

The method for finishing the polyformaldehyde fibers comprises the steps of firstly finishing the polyformaldehyde fibers through a first finishing liquid, forming a complex through a metal coordination agent and polycarboxylic acid, constructing a rough structure on the surfaces of the polyformaldehyde fibers, and then constructing a low surface energy structure with a room-temperature self-repairing function on the surfaces of the rough structure to synergistically improve a hydrophobic effect, so that the polyformaldehyde fibers have super-hydrophobic performance. Compared with the existing super-hydrophobic coating, the super-hydrophobic coating provided by the invention has the advantages of high self-repairing speed, long-acting stability of mechanical properties, intelligent and quick repairing without external stimulation, excellent antibacterial performance and the like, and the finishing method is simple, green and environment-friendly, low in cost and high in popularization and application value.

According to the invention, polyethylene glycol 1500 with a specific molecular weight is added, so that the mutual binding force between each component in the finishing liquid and the polyformaldehyde fiber can be effectively improved, the binding fastness of the finishing liquid and the polyformaldehyde fiber is improved, and the moisture-conducting effect of the polyformaldehyde fiber is favorably improved; in addition, the polyethylene glycol 1500 can also effectively prevent electrostatic aggregation and improve the antistatic performance of the polyformaldehyde fiber.

Preferably, in step a, the polycarboxylic acid is at least one of butane tetracarboxylic acid, propane tricarboxylic acid, maleic acid, citric acid, succinic acid, trimellitic acid, cyclobutane tetracarboxylic acid or itaconic acid.

Preferably, in the step a, the temperature for heating and dipping is 60-80 ℃ and the time is 3-6 min.

The optimal dipping temperature and time are favorable for maintaining the dimensional stability of the polyformaldehyde fibers, and simultaneously, the finishing liquid is favorably combined to the surfaces of the polyformaldehyde fibers, so that the comfort of the polyformaldehyde fibers is improved.

Preferably, the volume-to-mass ratio (bath ratio) of the polyformaldehyde fiber finishing liquid to the polyformaldehyde fibers is 10-30:1, wherein the mass unit is gram and the volume unit is milliliter.

The preferable proportion of the finishing liquid to the polyformaldehyde fibers can ensure that the finishing liquid uniformly covers the surfaces of the polyformaldehyde fibers and has higher bonding fastness after being dried.

Preferably, in step a, the metal ion complexing agent is one or two of ferric nitrate, ferric trichloride, bismuth nitrate and bismuth chloride.

The optimized metal ion coordination agent can form a metal complex with polycarboxylic acid, a rough structure is constructed on the surface of the polyformaldehyde fiber, the hydrophobic property is improved, a metal dynamic coordination bond can be formed with N connected with Si on a benzene ring in the polyformaldehyde fiber finishing agent, the self-repairing function is improved, and meanwhile, the formed metal complex has the effects of degrading pollutants and dyes and improving the self-cleaning function of the polyformaldehyde fiber.

Preferably, in the step a, the drying temperature is 105-110 ℃ and the drying time is 3-4 min.

Preferably, in the step b, the mass ratio of the polyformaldehyde fiber finishing agent to the nano-silica is 1: 1.0-1.5.

Preferably, in step b, the alcohol solvent is absolute ethanol.

Further preferably, in the step b, the volume-to-mass ratio of the nano silicon dioxide to the absolute ethyl alcohol is 1:18-22, wherein the volume unit is milliliter, and the mass unit is gram.

Preferably, the particle size of the nano silicon dioxide is 5nm-10 nm.

Preferably, in step c, the second finishing liquid is finished on the pretreated polyformaldehyde fibers by adopting a dipping, padding or spraying method.

The second finishing liquor can be repeatedly applied to the pretreated polyoxymethylene fibers by dipping, spraying or spraying to achieve the desired application level. The specific amount can be adjusted by routine.

The invention also provides a self-repairing super-hydrophobic fabric which is obtained by adopting any one of the polyformaldehyde fiber finishing methods.

The self-repairing super-hydrophobic fabric provided by the invention has an excellent super-hydrophobic function, also has a room-temperature intelligent and rapid self-repairing function, the repairing time is about 15min, the recovery period can reach 10 times, and the self-repairing super-hydrophobic fabric also has excellent antibacterial performance and self-cleaning performance, is a multifunctional self-repairing super-hydrophobic fabric, effectively expands the application of polyformaldehyde fibers, and has a wide market prospect.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

The embodiment of the invention provides a polyformaldehyde fiber finishing agent, which comprises the following steps:

dissolving 1.5mmol of o-aldehyde phenylboronic acid, 2.5mmol of amino-terminated polypropylene glycol and 0.3mmol of octadecylsilane in 5mL of anhydrous ethanol, uniformly mixing, cooling to 4 ℃, adding 1.5mmol of potassium borohydride, reacting for 2 days under the condition of heat preservation, extracting, and drying to obtain the polyformaldehyde fiber finishing agent.

The method for finishing the polyformaldehyde fibers by using the polyformaldehyde fiber finishing agent comprises the following steps:

step a, adding polyformaldehyde fibers into a first finishing liquid at a bath ratio of 10:1, heating to 80 ℃, dipping for 3min, and drying at 105 ℃ for 4min to obtain pretreated polyformaldehyde fibers;

the first finishing liquid comprises the following components in percentage by mass: 5% of maleic acid, 15001.0% of polyethylene glycol, 0.8% of sodium hypophosphite, 1.0% of ferric nitrate and the balance of water;

b, weighing the prepared polyformaldehyde fiber finishing agent and nano silicon dioxide according to the mass ratio of 1:1.2, adding the obtained materials into absolute ethyl alcohol, and performing ultrasonic dispersion for 4 hours to obtain a second finishing liquid; wherein, 18mL of absolute ethyl alcohol is added into every 1g of nano silicon dioxide;

and c, spraying the second finishing liquid on the pretreated polyformaldehyde fibers through a spray gun, spraying for 2 times under the pressure of 0.5kg, and drying to obtain the repaired super-hydrophobic fabric.

Example 2

The embodiment of the invention provides a polyformaldehyde fiber finishing agent, which comprises the following steps:

dissolving 2.5mmol of o-aldehyde phenylboronic acid, 1.5mmol of amino-terminated polypropylene glycol and 0.5mmol of octadecylsilane in 8mL of anhydrous ethanol, uniformly mixing, cooling to 0 ℃, adding 3.5mmol of ascorbic acid, reacting for 4 days under the condition of heat preservation, extracting, and drying to obtain the polyformaldehyde fiber finishing agent.

The method for finishing the polyformaldehyde fibers by using the polyformaldehyde fiber finishing agent comprises the following steps:

step a, adding polyformaldehyde fibers into a first finishing liquid at a bath ratio of 30:1, heating to 60 ℃, dipping for 6min, and drying at 110 ℃ for 3min to obtain pretreated polyformaldehyde fibers;

the first finishing liquid comprises the following components in percentage by mass: 10% of propane tricarboxylic acid, 15001.5% of polyethylene glycol, 0.5% of sodium hypophosphite, 2.0% of ferric trichloride and the balance of water;

b, weighing the prepared polyformaldehyde fiber finishing agent and nano silicon dioxide according to the mass ratio of 1:1.0, adding the obtained mixture into absolute ethyl alcohol, and performing ultrasonic dispersion for 5 hours to obtain a second finishing liquid; wherein, 22mL of absolute ethyl alcohol is added into every 1g of nano silicon dioxide;

and c, dipping the pretreated polyformaldehyde fibers into a second finishing liquid at the bath ratio of 10:1 and the dipping temperature of 20-30 ℃ for 30min, repeating dipping for 3 times, and drying to obtain the repaired super-hydrophobic fabric.

Example 3

The embodiment of the invention provides a polyformaldehyde fiber finishing agent, which comprises the following steps:

dissolving 2.0mmol of o-aldehyde phenylboronic acid, 2.0mmol of amino-terminated polypropylene glycol and 0.4mmol of octadecylsilane in 10mL of anhydrous ethanol, uniformly mixing, cooling to 2 ℃, adding 2.5mmol of sodium borohydride, reacting for 3 days under the condition of heat preservation, extracting, and drying to obtain the polyformaldehyde fiber finishing agent.

The method for finishing the polyformaldehyde fibers by using the polyformaldehyde fiber finishing agent comprises the following steps:

step a, adding polyformaldehyde fibers into a first finishing liquid at a bath ratio of 20:1, heating to 70 ℃, dipping for 5min, and drying at 105 ℃ for 3min to obtain pretreated polyformaldehyde fibers;

the first finishing liquid comprises the following components in percentage by mass: 8% of butane tetracarboxylic acid, 15001.2% of polyethylene glycol, 1.0% of sodium hypophosphite, 1.5% of bismuth nitrate and the balance of water;

b, weighing the prepared polyformaldehyde fiber finishing agent and nano silicon dioxide according to the mass ratio of 1:1.5, adding the obtained materials into absolute ethyl alcohol, and performing ultrasonic dispersion for 4 hours to obtain a second finishing liquid; wherein, 20mL of absolute ethyl alcohol is added into every 1g of nano silicon dioxide;

step c, dipping the pretreated polyformaldehyde fibers into a second finishing liquid, dipping and rolling for 30min at the bath ratio of 10:1 and the dipping temperature of 20-30 ℃ and under the pressure of 2-4kg/cm²Drying at 80 ℃ for 3min and at 110 ℃ for 3min, and obtaining the repair super-hydrophobic fabric.

The nano-silica used in examples 1 to 3 had a particle size of 5nm to 10nm, and the amino-terminated polypropylene glycol used had the following structural formula, wherein the degree of polymerization n was 6 to 15.

The content of the star polymer represented by the formula (I) in the polyoxymethylene fiber finishes prepared in examples 1 to 3 above was about 70 to 80%.

Comparative example 1

The comparative example provides a self-repairing hydrophobic fabric, the specific preparation method is completely the same as that of example 3, and the difference is that octadecylchlorosilane in the preparation process of the polyformaldehyde fiber finishing agent is replaced by equivalent dodecylchlorosilane.

Comparative example 2

The comparative example provides a self-repairing hydrophobic fabric, the specific preparation method is completely the same as that of example 3, and the difference is that octadecylchlorosilane in the preparation process of the polyformaldehyde fiber finishing agent is replaced by equivalent hexadecylchlorosilane.

Comparative example 3

The comparative example provides a self-repairing hydrophobic fabric, the specific preparation method is completely the same as that of example 3, and the difference is that octadecylchlorosilane in the preparation process of the polyformaldehyde fiber finishing agent is replaced by equivalent eicosylchlorosilane.

The fabric samples prepared in examples 1-3 and comparative examples 1-3 were tested.

According to GB/T20944.3-2008, evaluation of antibacterial performance of textiles part 3: and (3) measuring the antibacterial performance of the prepared fabric sample by a vibration method, wherein the strains are selected from escherichia coli and staphylococcus aureus.

Self-repairing test: and (3) irradiating and etching the prepared fabric sample for 15min by adopting a UV irradiation machine, changing the surface of the fabric into super-hydrophilic, putting the super-hydrophilic fabric into a climatic chamber (the temperature is 25 ℃, and the humidity is 99%) for repairing for 15min each time, repeatedly etching and repairing for 6 times, and testing the contact angle of the repaired fabric.

Self-cleaning performance test: 1.0g of the prepared fabric sample is put into 100mL of active blue 19 aqueous solution with the concentration of 50mg/L, then the mixture is placed into a photochemical reactor, a photodegradation test is carried out under the conditions of room temperature, pH 6 and xenon lamp illumination, the degradation is carried out for 120min, and the dye degradation rate is calculated.

And (3) whiteness testing: and respectively placing the polyformaldehyde fiber fabrics before and after finishing under a whiteness tester for whiteness test.

The test results are shown in table 1.

TABLE 1

The fabric samples prepared in examples 1 to 3 were subjected to a washing fastness test using a washing fastness tester at a washing temperature of 60 ℃ for 30min each time, and after 20 washes, the bacteriostatic rate, the contact angle after 6 repairs, and the dye degradation rate were tested according to the above conditions. The test results are shown in table 2.

TABLE 2

The original whiteness of the polyformaldehyde fibers before finishing is 90, and the whiteness of the polyformaldehyde fibers after finishing in examples 1-3 is 88.6-89, and basically, the polyformaldehyde fibers are unchanged, so that the polyformaldehyde fiber finishing agent and the finishing method provided by the invention can effectively solve the problem that the conventional finishing agent is easy to yellow after finishing fabrics.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.