阅读说明：本技术 一种高分子/改性有机蒙脱土激光标记材料及其制备方法和抗菌应用 (Polymer/modified organic montmorillonite laser marking material and preparation method and antibacterial application thereof ) 是由 曹峥 卢光威 王凯伦 高洪鑫 罗可铭 常嫄 王倩 杨雅雯 成骏峰 吴盾 刘春林 于 2020-07-03 设计创作，主要内容包括：本发明公开了高分子/改性有机蒙脱土激光标记材料及其制备方法和抗菌应用,先制备得到层间距增加以及表面修饰有机化官能团的改性蒙脱土；将有机改性蒙脱土、聚苯乙烯熔融共混,制备激光标记母粒,为了进一步提高其抗菌性和标记效果,还加入纳米氧化锌；按一定比例与高分子共混。通过激光打标机对复合材料进行表面激光处理,本发明利用有机蒙脱土的近红外吸收特性以及层间聚苯乙烯高温易碳化特性,诱导高分子基体表面形成黑色碳化以及多孔疏水的表面结构,得到清晰的激光标记图案；表面激光处理后,纳米抗菌的氧化锌颗粒暴露于材料表面,利用纳米氧化锌的抗菌特性以及激光处理后的多孔疏水结构使材料表面具有优异的抗菌性能。(The invention discloses a macromolecule/modified organic montmorillonite laser marking material and a preparation method and antibacterial application thereof, wherein modified montmorillonite with increased interlayer spacing and surface modified organic functional groups is prepared; the method comprises the following steps of (1) melting and blending organic modified montmorillonite and polystyrene to prepare a laser marking master batch, and adding nano zinc oxide in order to further improve the antibacterial property and the marking effect of the laser marking master batch; blending with polymer according to a certain proportion. The method comprises the following steps of carrying out surface laser treatment on a composite material by a laser marking machine, and inducing the surface of a high polymer matrix to form a black carbonized and porous hydrophobic surface structure by utilizing the near infrared absorption characteristic of organic montmorillonite and the high-temperature easy carbonization characteristic of interlayer polystyrene so as to obtain a clear laser marking pattern; after the surface is treated by laser, the nano antibacterial zinc oxide particles are exposed on the surface of the material, and the surface of the material has excellent antibacterial performance by utilizing the antibacterial property of the nano zinc oxide and the porous hydrophobic structure after the surface is treated by the laser.)

1. A high molecular/modified organic montmorillonite laser marking material is characterized in that: the laser marking material comprises, by weight, 100 parts of a polymer, 1-8 parts of a laser marking master batch containing montmorillonite, and 0.1-2 parts of an antioxidant.

2. The polymer/modified organo montmorillonite laser marking material as claimed in claim 1, wherein: the polymer is one or a mixture of acrylonitrile-butadiene-styrene terpolymer, polyethylene, polypropylene and thermoplastic polyurethane.

3. The polymer/modified organo montmorillonite laser marking material as claimed in claim 2, wherein: the laser marking master batch comprises organic modified montmorillonite and polymer material which are blended according to the mass ratio of 7: 9.

4. The polymer/modified organo montmorillonite laser marking material as claimed in claim 3, wherein: the laser marking master batch also comprises nano zinc oxide, and the addition amount of the nano zinc oxide is 50-60% of that of the organic modified montmorillonite.

5. A method for preparing the polymer/modified organic montmorillonite laser marking material as claimed in any one of claims 1-4, which is characterized in that:

(1) modifying montmorillonite with a coupling agent, and then modifying with a surfactant to obtain organic modified montmorillonite;

(2) adopting a melt blending method to melt and blend the organic modified montmorillonite or the mixed particles of the organic modified montmorillonite and the nano zinc oxide, the polystyrene and the antioxidant to prepare a laser marking master batch (polystyrene/OMMT or polystyrene/OMMT/zinc oxide) containing montmorillonite;

(3) melting and blending the montmorillonite-containing laser marking master batch, a polymer base material and an antioxidant to prepare a polymer composite material laser material (polymer/OMMT or polymer/OMMT/zinc oxide);

(4) and (4) carrying out laser marking on the laser material prepared in the step (3).

6. The method for preparing the polymer/modified organic montmorillonite laser marking material as claimed in claim 5, wherein the method comprises the following steps: the coupling agent in the step (1) is silane coupling agent KH550, KH-560, KH570 or titanate coupling agent tetrabutyl titanate; the surfactant is cetyl trimethyl ammonium bromide CTAB.

7. The method for preparing the polymer/modified organic montmorillonite laser marking material as claimed in claim 5, wherein the step (2) uses a torque rheometer to perform blending operation, the temperature is set to be 200-210 ℃, the rotation speed is 30-45r/min, the blending time is 5-6 min, so that the raw materials are fully and uniformly melted, and then tabletting and granulating are performed.

8. The method for preparing the polymer/modified organic montmorillonite laser marking material as claimed in claim 5, wherein the method comprises the following steps: the processing method in the step (4) comprises the following steps: carrying out surface laser marking treatment on the prepared laser material by using yttrium aluminum garnet crystal pulse laser, wherein the laser current intensity is set to be 7-11A, and the pulse laser wavelength is as follows: 1064 nm.

9. Use of the polymeric/OMMT/ZnO laser marking material prepared according to the method of claim 5 as an antimicrobial laser product.

Technical Field

The invention belongs to the field of new polymer materials, and particularly relates to surface laser treatment and antibacterial application of a polymer/modified organic montmorillonite/zinc oxide composite material.

Background

The laser marking technology is widely applied to character and pattern marking on the surfaces of plastics, metals and ceramics, and part of high polymer materials such as polyolefin, thermoplastic polyurethane, high polymer and the like have poor laser sensitivity and are difficult to absorb laser energy, so that the marking application of the laser marking technology on the surfaces of high polymer products is limited. In order to solve such problems, inorganic laser sensitive particles are usually required to be introduced into a polymer matrix to prepare a material capable of being marked by laser, and the inorganic laser sensitive particles are used for absorbing laser energy to realize photothermal conversion, so that polymer chains are carbonized and blackened to form a marked pattern.

The current patent reports the application of many inorganic laser-sensitive oxide particles in high-molecular laser marking, but still has many problems. The graphene oxide and the carbon nano tube are used as laser sensitive particles, so that the preparation is relatively complex, the cost is high, and the large-scale industrial application is influenced; the laser sensitive particles such as bismuth oxide and antimony trioxide contain metal elements such as bismuth and antimony, which are easily leaked from the polymer matrix. Therefore, there is a need to develop a laser-sensitive particle with wide source, low cost, environmental protection and easy application, and to develop laser marking application in polymer materials.

In the art, the use of mica, TiO₂Inorganic compounds such as these have also been used as laser marking additives, but they are often difficult to use alone, and the color contrast after marking is not clear, making it difficult to obtain good marking effects. Therefore, mica and TiO are generally used₂Such inorganic compounds are often used in combination with other color-changing salts (e.g., metal salts such as Cu, Fe, Sn, Sb, etc.), thereby providing a high-contrast marking effect. How to obtain the inorganic mineral material laser marking additive which can still obtain good marking effect without compounding metal salt is the technical problem to be solved by the invention.

In the process of solving the technical problems, the inventor firstly finds that the nano montmorillonite has a remarkable application effect in the aspect of laser marking. The nano montmorillonite belongs to an inorganic clay material, and has unique layered one-dimensional nano structure characteristics, designable reactivity, ultra-large specific surface area and good cation exchange capacity among layers. Has been widely used in textile, adsorption material, coating, medicine and other industries. The patent is supposed to find that the modified montmorillonite has excellent sensitivity under laser irradiation, introduces a high-molecular matrix material as a laser sensitive additive and researches the laser marking performance, and finds that the montmorillonite only adopts the organically modified montmorillonite as the laser marking additive, does not need to be compounded with other traditional laser marking additives for compounding use, and can also achieve remarkable laser effect.

The invention also introduces organic modified montmorillonite and nano-antibacterial zinc oxide into the polymer material, which not only improves the mechanical property of the polymer, but also opens up a new way for the laser marking of the polymer and the improvement of the antibacterial property. After the surface of the composite material is subjected to laser treatment, compared with the situation that nano antibacterial zinc oxide particles are exposed on the surface of the material before laser treatment, the antibacterial effect is achieved, and at present, reports that the surface of the material has excellent antibacterial performance by utilizing the antibacterial property of nano zinc oxide and a porous hydrophobic structure after laser treatment are not found.

Disclosure of Invention

The invention provides a surface laser treatment and antibacterial application of a polymer/modified organic montmorillonite/zinc oxide composite material, belonging to the field of new polymer materials. The invention firstly discovers that the modified organic montmorillonite has excellent laser sensitivity and can achieve obvious laser effect after application, and secondly after the organic montmorillonite and the zinc oxide are compounded for use, the nano zinc oxide antibacterial particles embedded in the matrix can be exposed out of the surface of the matrix after laser treatment, and meanwhile, the material has more excellent antibacterial performance after the cooperation of the porous and hydrophobic structures marked by the laser.

The polymer/modified organic montmorillonite composite material comprises, by weight, 100 parts of a polymer, 1-8 parts of a laser marking master batch and 0.1-2 parts of an antioxidant.

The polymer is acrylonitrile-butadiene-styrene terpolymer, polyethylene (processing temperature is 120-130 ℃), polypropylene (processing temperature is 170-180 ℃), thermoplastic polyurethane (processing temperature is 200-210 ℃) and the like.

The preparation method of the polymer/modified organic montmorillonite composite material comprises the following steps:

(1) modifying montmorillonite with silane coupling agent or/and titanate coupling agent: uniformly stirring methanol and water (volume ratio is 9:1), adding a coupling agent into the mixed solution, adjusting the pH value to 5.5 by using glacial acetic acid, heating in an oil bath at 56 ℃, reacting at constant temperature for 1.5h, heating to 85 ℃, adding montmorillonite, stirring at constant temperature for reacting for 2h, washing by using methanol, filtering, and drying at 60 ℃ to obtain the coupling agent modified montmorillonite.

Furthermore, the montmorillonite is sodium montmorillonite with the particle size range of 10-200 nm.

Further, the coupling agent in the step (1) is one of silane coupling agents KH550, KH-560 and KH570, the titanate coupling agent is tetrabutyl titanate, and the concentration of the coupling agent in the mixed solution is 1-4 vol.%. The concentration of the montmorillonite in the mixed solution is 1-3 g/100 mL.

Modifying montmorillonite with surfactant, adding coupling agent modified montmorillonite into water, stirring and dispersing uniformly, slowly dropwise adding surfactant aqueous solution at 70 ℃ for reacting for 6h, washing with ethanol and water until no bromide ion exists, and drying at 60 ℃ to obtain the organic montmorillonite.

Further, the surfactant in the step (1) is cetyl trimethyl ammonium bromide CTAB, and the concentration of the aqueous solution is 6-10 mg/mL. The addition amount of the coupling agent modified montmorillonite is 3-5 g/100 mL.

(2) Blending the organic modified montmorillonite and polystyrene high polymer material by adopting a melt blending method to prepare master batch (PS/OMMT) with laser marks;

the preparation method comprises the following steps of carrying out blending operation on 35 parts of organic modified montmorillonite, 45 parts of polystyrene and an antioxidant by using a torque rheometer, setting the temperature to be 200-210 ℃, the rotating speed to be 30-45r/min and the blending time to be 5-6 min, fully and uniformly melting the modified montmorillonite, the antioxidant and the polystyrene, and then crushing and granulating to obtain the laser marked master batch. Wherein the antioxidant accounts for 1-3% of the mass of the polystyrene.

The compatibility of the inorganic material and the matrix material can be better increased by preparing the master batch firstly, and the dosage of the additive can be better controlled.

(3) And melting, blending and molding the laser marking master batch, the polymer and the antioxidant to obtain the polymer composite material laser base material.

And (3) performing blending operation by using a torque rheometer, wherein the temperature of each zone of the torque rheometer is set to be 180-210 ℃, the rotating speed is 45-50 r/min, and the blending time is 8-10 min, so that the laser marked master batch, the antioxidant and the polymer matrix are fully and uniformly melted and then placed into a tablet press, the temperature is set to be 180-210 ℃, preheating is performed for 1min, tabletting is performed for 3min, and cold pressing is performed for 2min, so that a sample tablet of the polymer/modified organic montmorillonite composite material is prepared.

(4) And (4) carrying out laser marking on the polymer composite material laser base material formed in the step (3).

In order to further enable the laser marked master batch to have antibacterial performance, nano zinc oxide can be added into the laser marked master batch, and the polymer/modified organic montmorillonite/zinc oxide composite material is prepared by adopting the method.

The addition amount of the nano zinc oxide is 50-60% of that of the organic modified montmorillonite.

The laser marking method comprises the following steps: carrying out surface laser marking treatment on the polymer/modified organic montmorillonite or the polymer/modified organic montmorillonite/zinc oxide composite material by using yttrium aluminum garnet crystal pulse laser, wherein the laser current intensity is respectively set to be 7A, 8A, 9A, 10A and 11A, and the wavelength of the pulse laser 9 is as follows: 1064 nm.

The polymer/modified organic montmorillonite/zinc oxide composite material prepared by the method can be characterized by means of a scanning electron microscope, color difference analysis, antibacterial test and the like, after surface laser treatment, nano antibacterial zinc oxide particles are exposed on the surface of the material, and the antibacterial property of the nano zinc oxide and the porous hydrophobic structure after the laser treatment are utilized to ensure that the surface of the material has excellent antibacterial performance.

The invention firstly carries out pretreatment on the surface of the organic montmorillonite, which is a very important step. Alkyl ammonium ions on CTAB molecules can enter a montmorillonite layer through ion exchange reaction, and the surface of the montmorillonite layer is covered by alkyl long chains, so that the surface is changed from hydrophilicity to lipophilicity, and the affinity of montmorillonite and an organic phase is increased. Long carbon chain based quaternary ammonium salts (e.g., octadecyl or hexadecylammonium chloride, etc.) are the most used modifiers for montmorillonite. The silane coupling agent is chemically adsorbed or chemically reacted with the surface of the montmorillonite under proper conditions, so that the silane coupling agent is covered on the surface of the particles to achieve the aim of modification, promote the compatibility between the montmorillonite and the polymer matrix and ensure good mechanical property. Meanwhile, the montmorillonite after the modification is irradiated by near-infrared laser (with the wavelength of 1064 nm), compared with the montmorillonite before the modification, the montmorillonite after the modification can absorb the near-infrared laser energy more easily to generate photo-thermal conversion and cause local high heat, and meanwhile, the polystyrene in the master batch has the characteristic of high temperature and easy carbonization, so that black carbonization and a porous hydrophobic surface structure are formed on the surface of a polymer matrix to obtain a clear laser marking pattern. Therefore, the invention can still obtain obvious laser marking effect only by adopting the modified montmorillonite as the laser sensitive particles, and has obvious application prospect in the field of laser marking.

In addition, the nano zinc oxide is added into the polymer base material, nano antibacterial zinc oxide particles are exposed on the surface of the material after surface laser treatment, and the antibacterial property of the nano zinc oxide and the porous hydrophobic structure after laser treatment are utilized to enable the surface of the material to have excellent antibacterial performance, so that the nano zinc oxide can be used for preparing products such as antibacterial polymers.

Compared with other traditional high molecular material marks and antibacterial materials, the organic modified montmorillonite adopted by the invention has the advantages of wide sources, low cost, environmental protection and easy application. The surface after laser treatment presents a porous structure and hydrophobic performance, nano zinc oxide embedded in the matrix is exposed, and the surface with excellent laser marking and antibacterial performance is prepared through the antibacterial action of the nano zinc oxide.

Drawings

FIG. 1 is a photograph of the polymer/modified organic montmorillonite composite and the polymer after laser irradiation.

FIG. 2 is the scanning electron microscope photographs of the polymer/modified organic montmorillonite/zinc oxide composite material before and after marking.

FIG. 3 shows the surface contact angle of the polymer/modified organic montmorillonite/zinc oxide composite material after laser treatment.

FIG. 4 is a schematic diagram of the laser marking and antibacterial surface preparation of the polymer/modified organic montmorillonite/zinc oxide composite material.

Detailed Description

The invention is described in more detail below with reference to the following examples: