Recyclable, super-hydrophobic and antifouling dynamic crosslinking poly (urea-imine) coating for polyester fabric modification

Abstract

The invention discloses a recoverable, super-hydrophobic and antifouling dynamic crosslinking poly (urea-imine) coating material for polyester fabric modification, and the coating modified polyester fabric composite material is composed of a dynamic reversible poly (urea-imine) network and a fabric matrix, wherein the poly (urea-imine) coating is formed by dynamic covalent cross-linking reaction of terephthalaldehyde, a triamine cross-linking agent and an isocyanate monomer according to a specific ratio. The super-hydrophobic characteristic that the contact angle of the surface layer of the fabric is 135.62 + / -4 degrees is achieved, meanwhile, the tensile strength of the fabric is improved to 22.6 MPa (improved by 927%) compared with 2.2 MPa of an original polyester fabric, an interface interpenetrating structure is formed by a cross-linked network and the polyester fabric through molecular design, the flexibility of the fabric is kept while the mechanical property is enhanced, and excellent anti-fouling oil absorbency is achieved. According to the invention, the double-dynamic reversible characteristics of ureido hydrogen bonds and imine bonds are utilized, so that the composite material can be subjected to thermocompression welding or solvent treatment to realize complete recovery of the coating, and the environment-friendly problem that the traditional coating material is difficult to dissolve and recover is solved. In addition, the invention provides a high-performance, sustainable and multifunctional modification scheme for the polyester fabric, and the polyester fabric can be broadened in application in the fields of ocean engineering, outdoor equipment and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of cross-linked dynamic polymer materials, and particularly relates to a recyclable, super-hydrophobic and anti-fouling type dynamic cross-linked poly(urea-imide) coating for polyester fabric modification. BACKGROUND

[0002] Polyester fabric is widely used due to its good comprehensive performance, low cost and high strength. In addition, polyester fabric is a fibrous material with a certain length-diameter ratio prepared from polyester fibers, has the advantages of large surface area, many active groups and easy dispersion, and is easy to be compounded with other materials. However, the polyester fabric has the disadvantages of poor hydrophobicity and poor anti-fouling property due to the existence of polar ester groups. Cross-linked polymer material is an important polymer material in which monomers are linked by covalent bonds and a three-dimensional network structure is formed between molecular chains. However, the traditional cross-linked polymer material is difficult to degrade and recycle due to the permanent covalent cross-linking. In recent years, dynamic covalent cross-linked polymer has become a research hotspot due to its reversible structure. The cross-linking bond is dynamically reversible, and can endow the polymer with self-repairing, shape memory and reprocessing properties under certain conditions. In recent years, many studies have focused on dynamic polyimine polymer. Based on this, a new concept of cross-linked poly(urea-imide) polymer is designed, which has the dynamic characteristics of both imine bond and hydrogen bond, and the bond formation and breakage can be controlled by changing conditions such as temperature, pH value, etc. For example, the imine bond may dissociate when the temperature rises, and re-form when the temperature decreases. This dynamic behavior can form a dynamically controllable network structure in the polymer, but the imine bond also makes the polymer unstable in performance and the mechanical strength is not ideal. In addition, the addition of urea group structure in the polymer can make up for the adhesion, mechanical strength and dynamic characteristics of the imine polymer to a certain extent. In addition, there is no report on the preparation of a recyclable, super-hydrophobic cross-linked dynamic poly(urea-imide) coating for modifying polyester fabric. The application will help to expand the application of dynamic poly(urea-imide) coating modified polyester fabric materials in the fields of environmental remediation and marine engineering. SUMMARY

[0003] The application aims to overcome the performance deficiencies of the coating of the traditional polyester fabric in recycling, hydrophobicity, welding and anti-fouling, and provides a recyclable, super-hydrophobic, weldable and anti-fouling type dynamic cross-linked poly(urea-imide) coating for coating polyester fabric. The prepared poly(urea-imide) resin is first dissolved and recycled into a solution with different concentrations by using a low-boiling-point chloroform recycling method, and then the prepared alkali-treated polyester fabric is immersed in the recycled solution, and a modified polyester fabric is obtained after drying and curing, which is coated with a recyclable, super-hydrophobic, weldable and anti-fouling type dynamic cross-linked poly(urea-imide) coating.

[0004] In order to achieve the above-mentioned purpose, the technical scheme adopted by the application is as follows:

[0005] A recyclable, super-hydrophobic and anti-fouling dynamic cross-linking poly (urea-imide) coating for polyester fabric modification, comprising a dynamic cross-linking poly (urea-imide) film and a poly (urea-imide) coating for polyester fabric modification, the preparation steps are as follows:

[0006] Step one: preparation of poly (urea-imide) film. Mix and stir the three commercially available monomers TA, IPDI, T-403 and solvent (DMF) according to certain proportion and sequence, and dry to form a film.

[0007] Preferably, the molar ratio of the three monomers in step one is n TA :n IPDI :n T-403 = 6.6:0.6:4.8, because its performance retention rate is still high after multiple recycling, and it also has excellent hydrophobic, adhesion and anti-fouling properties.

[0008] Step two: completely dissolve the poly (urea-imide) film with an organic solvent, completely immerse the alkali-treated polyester fabric, rinse, dry, and obtain a recyclable, super-hydrophobic, cross-linking dynamic poly (urea-imide) coating modified polyester fabric.

[0009] Preferably, the dynamic cross-linking poly (urea-imide) coating solution is obtained by dissolving the dynamic cross-linking poly (urea-imide) resin with an organic solvent, and the organic solvent is chloroform with low boiling point, which is beneficial to its volatilization and removal. The solid content of poly (urea-imide) in the coating solution is 0.01wt%-5wt%, and the coating coverage of 1wt% polyester fabric can reach 6.03wt%, while the coating coverage of 0.5wt% polyester fabric is only 1.52wt%. Here, too much dynamic coating content of polyester fabric will affect the flexibility of the fabric, and too little dynamic coating content of polyester fabric will reduce the surface hydrophobic effect, which is not conducive to the welding effect of the fabric.

[0010] Preferably, the polyester fabric is treated with alkali, because the rough surface of the treated polyester fabric can enhance the adhesion of the coating. At the same time, there are still a large number of -OH groups on the surface of the polyester fabric.

[0011] Preferably, the poly (urea-imide) coating coated in the polyester fabric has both polyurea and imine structure and composition, in which the polyurea groups form a hydrogen bond network with the -OH groups remaining on the polyester fabric after alkali treatment, significantly improving the strength of the polyester fabric, as well as the adhesion and hydrophobic properties of the coating.

[0012] The above technical solution can achieve the following beneficial effects:

[0013] The composite material obtained by the above preparation method is a recyclable, super-hydrophobic cross-linked dynamic poly(urea-imide) coating modified polyester fabric. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a poly(urea-imide) resin film synthesis solution diagram prepared in Example 1.

[0015] Figure 2 is a physical diagram of the poly(urea-imide) resin film prepared in Example 1.

[0016] Figure 3 is an infrared characteristic peak spectrum diagram of the poly(urea-imide) resin film prepared in Examples 1-4.

[0017] Figure 4 is a normal stress-strain performance comparison diagram of the poly(urea-imide) resin film prepared in Examples 1-4.

[0018] Figure 5 is a stress-strain performance comparison diagram of the poly(urea-imide) resin film prepared in Examples 1-4 after heat recovery.

[0019] Figure 6 is a stress-strain performance comparison diagram of the cross-linked dynamic poly(urea-imide) coating modified polyester fabric prepared in Example 5 after amino degradation recovery.

[0020] Figure 7 is a stress-strain performance comparison diagram of the cross-linked dynamic poly(urea-imide) coating modified polyester fabric prepared in Example 5 and the polyester fabric material.

[0021] Figure 8 is a physical diagram of the cross-linked dynamic poly(urea-imide) coating modified polyester fabric prepared in Example 5 and the polyester fabric material after stress-strain stretching.

[0022] Figure 9This is a comparison chart of the hydrophobic properties of the cross-linked dynamic poly(urea-imine) coating modified polyester fabric prepared in Example 5 and the polyester fabric material.

[0023] Figure 10 This is a comparison chart of the oil absorption before and after the cross-linked dynamic poly(urea-imine) coating modified polyester fabric prepared in Example 5 and the polyester fabric material.

[0024] Figure 11 This is a picture of the effect of the cross-linked dynamic poly(urea-imine) coating modified polyester fabric prepared in Example 5 hanging a heavy object, and its own mass is only 1.6283g.

[0025] Figure 12 This is one of the diagrams showing the preparation process of the cross-linked dynamic poly(urea-imine) coating modified polyester fabric prepared in Example 5. The poly(urea-imine) film was placed in a chloroform solution and completely dissolved at room temperature for 24 hours. DETAILED DESCRIPTION

[0026] The following is combined with Figures 1-12 The present invention will be further described:

[0027] A recyclable, super-hydrophobic, and antifouling dynamically cross-linked poly(urea-imide) coating for polyester fabric modification is prepared by adjusting the molar ratio of terephthalaldehyde (TA), isophorone diisocyanate (IPDI), and amino-terminated trimethylolpropane tripropylene glycol ether (T-403) to form a dual dynamic poly(urea-imide) coating. The chemical structures of the coating and the monomers are as follows:

[0028]

[0029]

[0030] The coating is a micro-nanoscale encapsulated dual dynamic coating formed by completely impregnating polyester fabric with a dynamic cross-linked poly(urea-imine) solution and curing it by heating.

[0031] Poly(urea-imide) coating is a type of dual dynamic cross-linked structure, the sum of the amount of aldehyde and isocyanate functional groups is equal to the total amount of amino groups, and the molar ratio of the reactive monomers is n TA :n IPDI :n T-403 =6.6:0.6:4.8.

[0032] The dynamically cross-linked poly(urea-imine) coating liquid is obtained by dissolving a dynamically cross-linked poly(urea-imine) resin in an organic solvent. The solid content of poly(urea-imine) in the coating liquid is between 0.01 wt% and 5 wt%. The coating coverage of 1 wt% polyester fabric can reach 6.03 wt%, while the coating coverage of 0.5 wt% polyester fabric is only 1.52 wt%.

[0033] The coating modified polyester fabric can be hot press welded, wherein the double dynamic coating can be solvent dissolved and recycled.

[0034] Application of a recyclable, super-hydrophobic and anti-fouling type dynamic crosslinking poly(urea-imide) coating for polyester fabric modification, adding graphene, carbon nanotubes, boron nitride or composite fillers as heat-conducting fillers or as a recyclable heat-dissipating coating.

[0035] Comparative Example 1 Figure 8 The stress-strain tensile comparison of polyester fabric and crosslinking type dynamic poly(urea-imide) coating modified polyester fabric is shown in the figure. After the polyester fabric is stretched to a certain strength, the shape is severely damaged. The crosslinking type dynamic poly(urea-imide) coating modified polyester fabric still maintains the basic shape and is not damaged.

[0036] Comparative Example 1 Figure 9 The hydrophobic property comparison of polyester fabric and crosslinking type dynamic poly(urea-imide) coating modified polyester fabric. The polyester fabric is instantly water-absorbed, while the crosslinking type dynamic poly(urea-imide) coating modified polyester fabric has super-hydrophobicity. The greater the mass fraction of poly(urea-imide) film, the stronger the hydrophobicity.

[0037] Comparative Example 1 Figure 10 The oil absorption comparison of polyester fabric and crosslinking type dynamic poly(urea-imide) coating modified polyester fabric is shown in the figure. Red is an organic solvent simulating heavy oil. The poly(urea-imide) coating modified polyester fabric can instantly absorb and completely absorb heavy oil, while the polyester fabric cannot achieve this excellent effect.

[0038] Comparative Example 1

[0039] In a 2L beaker, 800mL of deionized water was added, 10g of NaOH was weighed and poured into the beaker, and the beaker was placed in a 75℃ water bath to heat until the NaOH was completely dissolved. A certain amount of polyester fabric was cut and placed in the beaker, and stirred for 2hrs to allow the polyester fabric to be treated with alkali. The alkali-treated polyester fabric was taken out, rinsed with deionized water for 3-6 times, and the rinsed polyester fabric was placed in an 80℃ air oven to dry for 12hrs until it was completely dried.

[0040] Example 1

[0041] Mix 0.886g of terephthalaldehyde (TA) powder with 24.2g of N,N-dimethylacetamide (DMF) and stir for 10 minutes until the TA is completely dissolved. Next, add 2.112g of trimethylolpropane tripropylene glycol ether (amino-terminated) (T-403) and 1g of DMF to the solution and stir for 10 minutes. Then, add 0.134g of isophorone diisocyanate (IPDI) and 1g of DMF to a beaker and stir for 2 minutes. Pour the stirred solution into a PTFE mold and dry it in a forced-air oven at 60°C for 18 hours. Remove the dried poly(urea-imide) film with tweezers and place it in a vacuum oven at 150°C for 1 hour.

[0042] Example 2

[0043] Mix 0.804g of terephthalaldehyde (TA) powder with 26.6g of N,N-dimethylacetamide (DMF) and stir for 10 minutes until the TA is completely dissolved. Next, add 2.112g of amino-terminated trimethylolpropane tripropylene glycol ether (T-403) and 1g of DMF to the solution and stir for 10 minutes. Then, add 0.266g of isophorone diisocyanate (IPDI) and 1g of DMF to a beaker and stir for 2 minutes. Pour the stirred solution into a PTFE mold and dry it in a forced-air oven at 60°C for 18 hours. Remove the dried poly(urea-imide) film with tweezers and place it in a vacuum oven at 150°C for 1 hour.

[0044] Example 3

[0045] Mix 0.643g of terephthalaldehyde (TA) powder with 28.1g of N,N-dimethylacetamide (DMF) and stir for 10 minutes until the TA is completely dissolved. Next, add 2.112g of amino-terminated trimethylolpropane tripropylene glycol ether (T-403) and 1g of DMF to the solution and stir for 10 minutes. Then, add 0.533g of isophorone diisocyanate (IPDI) and 1g of DMF to a beaker and stir for 2 minutes. Pour the stirred solution into a PTFE mold and dry it in a forced-air oven at 60°C for 18 hours. Remove the dried poly(urea-imide) film with tweezers and place it in a vacuum oven at 150°C for 1 hour.

[0046] Example 4

[0047] A solution of 0.402 g of terephthaldehyde (TA) powder was mixed with 24.4 g of N,N-dimethylacetamide (DMF) and stirred for 10 min until the TA was completely dissolved. Then 1.760 g of trihydroxymethylpropane trimeric propylene glycol ether (amino-terminated) (T-403) and 1 g of DMF were added to the solution and stirred for 10 min. Then 0.666 g of isophorone diisocyanate (IPDI) and 1 g of DMF were added to the solution and stirred for 2 min. The stirred solution was poured into a Teflon mold. The mold was placed in a forced air oven at 60 °C for 18 hrs. The dried poly(urea-imine) film was removed with tweezers and placed in a vacuum oven at 150 °C for 1 hr.

[0048] Figure 1 A solution of the poly(urea-imine) film prepared in Example 1 was mixed with three monomers and poured into a Teflon mold to obtain a poly(urea-imine) film.

[0049] Figure 2 A physical sample of the poly(urea-imine) film material prepared in Example 1.

[0050] Figure 3 The infrared spectra of the poly(urea-imine) films prepared in Examples 1-4. -1 The characteristic peaks of the imine bond at 1639 cm -1 and the aldehyde group at 1690 cm

[0051] Figure 4 The normal stress-strain properties of the poly(urea-imine) films prepared in Examples 1-4. Figure 5 The stress-strain properties of the poly(urea-imine) films prepared in Examples 3 and 4 after heat recovery.

[0052] Example 5

[0053] A solution of 0.402 g of terephthaldehyde (TA) powder was mixed with 24.4 g of N,N-dimethylacetamide (DMF) and stirred for 10 min until the TA was completely dissolved. Then 1.760 g of trihydroxymethylpropane trimeric propylene glycol ether (amino-terminated) (T-403) and 1 g of DMF were added to the solution and stirred for 10 min. Then 0.666 g of isophorone diisocyanate (IPDI) and 1 g of DMF were added to the solution and stirred for 2 min. The stirred solution was poured into a Teflon mold. The mold was placed in a forced air oven at 60 °C for 18 hrs. The dried poly(urea-imine) film was removed with tweezers and placed in a vacuum oven at 150 °C for 1 hr.

[0054] At room temperature, 1 g and 0.5 g of CPUI-1 poly(urea-imine) film were weighed and added to 100 g of chloroform solution, respectively, and stirred for 12-18 hrs until the CPUI-1 film was completely dissolved and recovered, obtaining CPUI-1 recovery liquid with a mass fraction of 0.05% and 0.1%, respectively. Then 800 mL of deionized water was added to a 2 L beaker, 10 g of NaOH was weighed and poured into the beaker, and the beaker was placed in a 75°C water bath and heated until the NaOH was completely dissolved. A certain amount of polyester fabric was cut and placed in the beaker, and stirred for 2 hrs to allow the polyester fabric to be treated with alkali. The alkali-treated polyester fabric was removed, rinsed with deionized water for 3-6 times, and the rinsed polyester fabric was placed in an 80°C air oven and dried for 12 hrs to completely dry. The dried alkali-treated polyester fabric was completely immersed in the CPUI-1 recovery liquid and immersed for 18-24 hrs. It was rinsed with deionized water for 3-6 times and placed in an 80°C air oven and dried for 12 hrs to completely dry, and finally obtained a CPUI-1 polyimine coating modified polyester fabric.

[0055] Figure 6 Stress-strain performance comparison chart of amino degradation recovery of cross-linked dynamic poly(urea-imine) coating modified polyester fabric prepared for Examples 2-4. The poly(urea-imine) coating can be recycled into a poly(urea-imine) film, even if the tensile strength and elastic modulus are slightly lower than the original poly(urea-imine) film, but it shows that the cross-linked dynamic poly(urea-imine) coating modified polyester fabric still has good recycling and reprocessing properties.

[0056] Figure 7 Stress-strain performance comparison chart of cross-linked dynamic poly(urea-imine) coating modified polyester fabric prepared for Example 5 and polyester fabric material. Compared with the polyester fabric, the tensile strength is increased from 2.2 MPa to 22.6 MPa, an increase of 927%. It shows that the cross-linked dynamic poly(urea-imine) coating modified polyester fabric greatly improves its mechanical properties.

[0057] The coating modified polyester fabric composite is composed of a dynamic reversible poly(urea-imine) network and a fabric substrate, wherein the poly(urea-imine) coating is formed through a dynamic covalent crosslinking reaction of a specific ratio of terephthaldehyde, a triamine crosslinking agent and an isocyanate monomer. The present application realizes the super-hydrophobic property of the fabric surface layer with a contact angle of 135.62±4°, and the tensile strength of the fabric is increased from 2.2 MPa of the original polyester fabric to 22.6 MPa (an increase of 927%), the interface interpenetrating structure of the crosslinking network and the polyester fabric is formed through molecular design, the mechanical property is enhanced, the fabric flexibility is maintained, and excellent oil-repellent and oil-absorbing properties are also provided. The present application utilizes the double dynamic reversible properties of the urea-based hydrogen bond and the imine bond, so that the composite material can be hot-pressed and welded, or the coating can be completely recycled through solvent treatment, thereby solving the environmental protection problem of the traditional coating material which is difficult to be dissolved and recycled. In addition, the present application provides a high-performance, sustainable and multifunctional modification scheme for polyester fabric, and can widen the application in the fields of marine engineering and outdoor equipment.

[0058] The above are preferred embodiments of the present application, and modifications of various equivalent forms of the present application without departing from the principles of the present application are within the protection scope of the appended claims of the present application.

Claims

1. A recyclable, superhydrophobic and anti-fouling dynamic cross-linked poly(urea-imide) coating for polyester fabric modification, characterized in that: The double dynamic poly (urea-imide) coating is prepared by regulating the monomer molar ratio of terephthaldehyde TA, isophorone diisocyanate IPDI and amino-terminated trimethylolpropane tris (2-oxo-propyl) ether T-403, and the chemical structural formula of the coating and monomers is as follows:

2. A recyclable, superhydrophobic and anti-fouling dynamic cross-linked poly(urea- imide) coating for polyester fabric modification according to claim 1, characterized by: The coating is a micro-nano scale double dynamic coating formed by completely immersing a polyester fabric in a dynamic cross-linking poly (urea-imide) solution, and then curing by temperature rising.

3. A recyclable, superhydrophobic and anti-fouling dynamic cross-linked poly (urea- imide) coating for polyester fabric modification according to claim 1, characterized in that: The poly(urea-imide) coating is a class of dual dynamic cross-linked structure, the sum of the molar amount of aldehyde and isocyanate functional groups is equal to the total molar amount of amino groups, the reaction monomer molar ratio is n TA : 1 IPDI : 1 T-403 = 6.6:0.6:4.

8.

4. A recyclable, superhydrophobic and anti-fouling dynamic cross-linked poly(urea- imide) coating for polyester fabric modification according to claim 1, characterized by: The dynamic cross-linking poly (urea-imide) coating solution is obtained by dissolving a dynamic cross-linking poly (urea-imide) resin in an organic solvent, and the poly (urea-imide) solid content in the coating solution is 0.01wt%-5wt%, wherein the coating covering amount of 1wt% polyester fabric can reach 6.03wt%, and the coating covering amount of 0.5wt% polyester fabric is only 1.52wt%.

5. A recyclable, superhydrophobic and anti-fouling dynamic cross-linked poly(urea- imide) coating for polyester fabric modification according to claim 1, characterized in that: The tensile mechanical properties of the polyester fabric coated by the coating are improved compared with unmodified polyester fabric, and the polyester fabric can be hot pressure welded and solvent-dissolved and recycled.

6. Use of a recyclable, superhydrophobic and antifouling dynamic cross-linked poly(urea-imide) coating for the modification of polyester fabrics, characterized in that: The heat-conducting filler such as graphene, carbon nanotube, boron nitride or composite filler can be added or used as a recyclable heat-dissipating coating.

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