A method for surface modification and electromagnetic shielding functionalization of UHMWPE fibers and fabrics

Abstract

The invention discloses a method for surface modification and electromagnetic shielding functionalization of UHMWPE fiber and fabric, S1: immersing UHMWPE fiber and fabric in anhydrous ethanol for ultrasonic cleaning, taking out and drying; S2: preparing an ethanol solution containing dopamine hydrochloride and trishydroxymethylaminomethane, adding zinc acetate dihydrate and sodium hydroxide, immersing the fiber and fabric in the solution, placing them in a shaker at 40-60°C for reaction for 12-24h, and the shaking rate is 60-120 r / min; S3: washing and oven annealing for standby use; S4: preparing ZnO growth solution; immersing the obtained fiber and fabric in the growth solution, keeping it at 90-98°C for a period of time, washing the product with deionized water and drying it in an oven, and obtaining modified UHMWPE fiber and fabric. The interface adhesion performance between UHMWPE fiber or fabric and resin matrix is ​​improved, and the UHMWPE fiber or fabric has certain electromagnetic shielding performance; the method of co-deposition of dopamine and ZnO is adopted to shorten the preparation process of ZnO Nps prepared by sol-gel method.

Description

Technical Field

[0001] The invention relates to the field of fiber and fabric surface modification, and in particular to a method for surface modification and electromagnetic shielding functionalization of UHMWPE fibers and fabrics. Background Art

[0002] Ultra-high molecular weight polyethylene (UHMWPE) fiber and fabric composite materials have excellent energy absorption characteristics and anti-ballistic performance, and are widely used in military defense fields such as impact resistance and bulletproof. However, due to the lack of polar groups on the surface of UHMWPE fibers and fabrics, the adhesion between them and the matrix is ​​poor, and the interface bonding force is low, which restricts the further improvement of the comprehensive performance of UHMWPE fiber and fabric composite materials and limits the application of UHMWPE fiber and fabric composite materials.

[0003] Surface modification of UHMWPE fibers and fabrics can improve their interfacial bonding properties. The main methods include plasma modification, irradiation grafting modification, chemical reagent modification, corona discharge modification and coating modification. Other methods include alkali treatment and introduction of nanoparticles. Among them, the coating method is a relatively simple and efficient method among many methods for optimizing the interface, and it will not damage the original mechanical properties of the fibers and fabrics.

[0004] Chu Yanyan and others from Zhongyuan University of Technology used the sol-gel method to grow nano zinc oxide on the surface of aramid fabric, carbon fiber fabric, and ultra-high performance polyethylene fabric to prepare a high-performance flexible bulletproof material with both electromagnetic shielding and UV resistance (CN110846894 A). This method has a long preparation process and the surface of the UHMWPE fabric is inert, and the binding force with the zinc oxide nanowires is not strong enough. Therefore, a method for surface modification and electromagnetic shielding functionalization of UHMWPE fibers and fabrics is provided. Summary of the invention

[0005] The purpose of the present invention is to provide a method for surface modification and electromagnetic shielding functionalization of UHMWPE fibers and fabrics in view of the defects of the prior art, so as to solve the problems raised by the above-mentioned background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for surface modification and electromagnetic shielding functionalization of UHMWPE fibers and fabrics, comprising the following steps:

[0007] S1: soak the UHMWPE fiber and fabric in anhydrous ethanol for ultrasonic cleaning, and then take them out and dry them;

[0008] S2: Prepare an ethanol solution containing dopamine hydrochloride and tris(hydroxymethylaminomethane), add zinc acetate dihydrate and sodium hydroxide, immerse the fiber and fabric obtained in S1 in the solution, place in a shaker at 40-60°C for 12-24 hours, and shake at a rate of 60-120 r / min;

[0009] S3: The fibers and fabrics obtained in S2 are washed with deionized water, and then placed in an oven at 90-100° C. for annealing for later use;

[0010] S4: uniformly mix zinc nitrate hexahydrate and hexamethylenetetramine to prepare a ZnO growth solution; immerse the obtained fiber and fabric in the growth solution, keep it at 90-98° C. for a period of time, wash the product with deionized water and dry it in an oven to obtain modified UHMWPE fiber and fabric.

[0011] As a preferred technical solution of the present invention, the concentration of zinc acetate dihydrate in S2 is 1.0-1.8 mM.

[0012] As a preferred technical solution of the present invention, the concentration of sodium hydroxide in S2 is 0.5-1.5 mM.

[0013] As a preferred technical solution of the present invention, the concentrations of zinc nitrate hexahydrate and hexamethylenetetramine in S4 are 0.02-0.03 mM.

[0014] The beneficial effects of the present invention are: dopamine and nano zinc oxide (ZnO NPs) are co-deposited on the surface of UHMWPE fiber or fabric to form a coating; the adhesion property of dopamine itself is used to improve the interface property of UHMWPE fiber or fabric, and the excellent dielectric property of ZnO NPs is used to make the UHMWPE fiber or fabric have certain electromagnetic shielding performance.

[0015] The modification method of the invention has mild reaction conditions, cheap and readily available raw materials, and is green, environmentally friendly and sustainable; it does not damage the mechanical properties of the UHMWPE fiber and the fabric itself, and improves the interface properties of the fiber and the fabric while enabling it to have certain electromagnetic shielding performance.

[0016] 1. The present invention improves the interfacial adhesion performance between UHMWPE fiber or fabric and resin matrix while making it have certain electromagnetic shielding performance;

[0017] 2. The present invention adopts the method of co-deposition of dopamine and ZnO, which shortens the preparation process of ZnO Nps by the sol-gel method. DETAILED DESCRIPTION

[0018] The preferred embodiments of the present invention are described in detail below so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0019] Embodiment 1:

[0020] S1: soak the ultra-high molecular weight polyethylene fiber and fabric in anhydrous ethanol for ultrasonic cleaning, and then take them out and dry them;

[0021] S2: Prepare 400 mL of 40% ethanol solution containing 0.8 g dopamine hydrochloride and 0.24 g tris(hydroxymethyl)aminomethane (Tris), add 0.12 g zinc acetate dihydrate, stir evenly, then add 35 mL 1 mM sodium hydroxide, immerse the fibers and fabrics obtained in S1 in the solution, place in a shaker at 50 °C for 24 h, and stir at a rate of 100 r / min.

[0022] S3: The fibers and fabrics obtained in S2 are washed with deionized water, and then placed in a 100°C oven for annealing for later use;

[0023] S4: 0.025 mM zinc nitrate hexahydrate and hexamethylenetetramine were uniformly mixed in a molar ratio of 1:1 to prepare a ZnO growth solution. The obtained fiber and fabric were immersed in the growth solution and kept at 95 °C for a period of time. The product was washed with deionized water and dried in an oven to obtain the modified UHMWPE fiber and fabric.

[0024] Embodiment 2:

[0025] S1: soak the ultra-high molecular weight polyethylene fiber and fabric in anhydrous ethanol for ultrasonic cleaning, and then take them out and dry them;

[0026] S2: Prepare 400 mL of 80% ethanol solution containing 0.8 g dopamine hydrochloride and 0.24 g tris(hydroxymethyl)aminomethane (Tris), add 0.12 g zinc acetate dihydrate and stir evenly, then add 35 mL 1 mM sodium hydroxide, immerse the fiber and fabric obtained in S1 in the solution, place in a shaker at 50 °C for 24 h, and stir at a rate of 100 r / min;

[0027] S3: The fibers and fabrics obtained in S2 are washed with deionized water, and then placed in a 100°C oven for annealing for later use;

[0028] S4: 0.02 mM zinc nitrate hexahydrate and hexamethylenetetramine are uniformly mixed in a molar ratio of 1:1 to prepare a ZnO growth solution; the obtained fiber and fabric are immersed in the growth solution and maintained at 95°C for a period of time; the product is washed with deionized water and dried in an oven to obtain modified UHMWPE fiber and fabric.

[0029] Embodiment 3:

[0030] S1: soak the ultra-high molecular weight polyethylene fiber and fabric in anhydrous ethanol for ultrasonic cleaning, and then take them out and dry them;

[0031] S2: Prepare 400 mL of 20% ethanol solution containing 0.8 g dopamine hydrochloride and 0.24 g tris(hydroxymethyl)aminomethane (Tris), add 0.12 g zinc acetate dihydrate, stir evenly, then add 35 mL 1 mM sodium hydroxide, immerse the fibers and fabrics obtained in S1 in the solution, place in a shaker at 50 °C for 24 h, and stir at a rate of 100 r / min.

[0032] S3: The fibers and fabrics obtained in S2 are washed with deionized water, and then placed in a 100°C oven for annealing for later use;

[0033] S4: 0.03 mM zinc nitrate hexahydrate and hexamethylenetetramine are uniformly mixed in a molar ratio of 1:1 to prepare a ZnO growth solution; the obtained fiber and fabric are immersed in the growth solution and maintained at 95°C for a period of time; the product is washed with deionized water and dried in an oven to obtain modified UHMWPE fiber and fabric.

[0034] Test example:

[0035] (1) Epoxy resin and polyetheramine curing agent were stirred and mixed in a weight ratio of 3:1, and then placed in a vacuum for degassing for 15 min to obtain a bubble-free resin liquid. A small amount of resin droplets were transferred to the surface of the test fiber using a needle tip, and then cured at 80 °C for 2 h to obtain a microsphere debonding sample.

[0036] The change in interfacial strength of the fibers obtained in Examples 1-3 before and after modification was tested by microsphere debonding experiments. The results are shown in Table 1.

[0037]

[0038] (2) The electromagnetic parameters of the fabric in the X-band were tested and its electromagnetic shielding effectiveness was calculated. The results are shown in Table 2.

[0039]

[0040] The present invention uses dopamine and nano zinc oxide (ZnO NPs) to co-deposit on the surface of UHMWPE fiber or fabric to form a coating; the adhesion property of dopamine itself is used to improve the interface performance of the UHMWPE fiber or fabric, and the excellent dielectric properties of ZnO NPs are used to make the UHMWPE fiber or fabric have certain electromagnetic shielding performance.

[0041] The modification method of the invention has mild reaction conditions, cheap and readily available raw materials, and is green, environmentally friendly and sustainable; it does not damage the mechanical properties of the UHMWPE fiber and the fabric itself, and improves the interface properties of the fiber and the fabric while enabling it to have certain electromagnetic shielding performance.

[0042] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention.

Claims

1. A method for surface modification and electromagnetic shielding functionalization of UHMWPE fibers or fabrics, characterized in that: The following steps are involved: S1: soak the UHMWPE fiber or fabric in anhydrous ethanol for ultrasonic cleaning, and then take it out and dry it; S2: prepare an ethanol solution containing dopamine hydrochloride and tris(hydroxymethyl)aminomethane, add zinc acetate dihydrate and sodium hydroxide, and immerse the fiber or fabric obtained in S1 in the solution, place it in a shaker at 40-60°C for 12-24 hours, and the shaking rate is 60-120r / min; the concentration of sodium hydroxide is 0.5-1.5mM; the concentration of zinc acetate dihydrate is 1.0-1.8mM; S3: washing the fiber or fabric obtained in S2 with deionized water, and then annealing in an oven at 90-100° C. for later use; S4: uniformly mix zinc nitrate hexahydrate and hexamethylenetetramine to prepare a ZnO growth solution; immerse the fiber or fabric obtained in S3 into the growth solution, keep it at 90-98°C for a period of time, wash the product with deionized water and dry it in an oven to obtain modified UHMWPE fiber or fabric; the concentration of zinc nitrate hexahydrate and hexamethylenetetramine is 0.02-0.03mM.

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