CN114957763B - A kind of superhydrophobic wear-resistant polypropylene coating and preparation method thereof - Google Patents

Abstract

The invention belongs to the technical field of polypropylene materials, and particularly relates to a super-hydrophobic wear-resistant polypropylene coating and a preparation method thereof. The preparation method comprises the following steps: 1) Dissolving a silane coupling agent containing a hydrophobic group in an ethanol solution, adding inorganic nanoparticles, stirring at the temperature of 20-70 ℃ for reaction, cleaning, and drying to obtain pretreated inorganic nanoparticles; 2) Dispersing the pretreated inorganic nanoparticles in xylene, heating, immersing a polypropylene test piece in the mixed solution for 10s-5min, and quickly pulling to obtain a polypropylene surface pre-modified sample; 3) And (3) immersing the polypropylene surface pre-modified sample into a toluene solution of a chlorosilane coupling agent containing hydrophobic groups, reacting at the temperature of 20-100 ℃, taking out and airing to obtain the super-hydrophobic wear-resistant polypropylene coating. The method can form a firm hydrophobic coating, and has good super-hydrophobicity and wear resistance.

Description

A kind of superhydrophobic wear-resistant polypropylene coating and preparation method thereof

technical field

The invention belongs to the technical field of polypropylene materials, and in particular relates to a superhydrophobic wear-resistant polypropylene coating and a preparation method thereof.

Background technique

Polypropylene (PP) is a semi-crystalline general-purpose plastic with excellent mechanical properties and chemical stability, excellent comprehensive properties, and a wide range of applications. The surface contact angle of ordinary polypropylene is about 100°, which is a general hydrophobic material. Its superhydrophobicity can improve its functionality and further expand its application field.

Chinese patent CN105860120A discloses a superhydrophobic polypropylene film and its preparation method. The isotactic polypropylene-b-polyethylene glycol block polymer solution is spin-coated on the polypropylene film and dried to obtain a superhydrophobic film.

Qiao Yanfang et al. used sandpaper to polish the surface of polypropylene in the same direction to obtain a oriented microstructure. The structure was subjected to UV/ozone treatment, chemical deposition of 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane, and perfluoropolyether perfusion. A lubricated surface was prepared with a water contact angle of 141° (Fine Chemical Industry, 2019, 36(10): 2023-2051); Ji Haiyan et al. prepared a superhydrophobic polypropylene film by a simple solvent/non-solvent method. The contact angle of water is 160°, and the rolling angle is less than 4° (Polymer Materials Science and Engineering, 2011, 27(8): 154-156). These technologies all graft low-surface-energy substances on the surface of polypropylene to achieve super-hydrophobic effects. However, in practical applications, low-surface-energy substances are easily decomposed by temperature, light, etc., and are more prone to mechanical friction or wear. It is damaged under the action, which affects the adhesion and wettability of the coating, resulting in the decrease or loss of superhydrophobic properties, which limits its application. Therefore, there is an urgent need to prepare a wear-resistant, hydrophobic and stable polypropylene surface coating.

In view of this, the present invention is proposed.

Contents of the invention

In order to solve the disadvantages of using low surface energy substances to improve the surface hydrophobicity of polypropylene in the prior art, such as easy decomposition and damage, the present invention provides a superhydrophobic wear-resistant polypropylene coating and its preparation method. Polypropylene is immersed in In the xylene solution containing the pretreated inorganic nanoparticles, the inorganic nanoparticles are embedded in the surface of the polypropylene matrix, and then further post-treated by a chlorosilane coupling agent containing hydrophobic groups to form a firm hydrophobic coating, which has Good superhydrophobicity and abrasion resistance.

The present invention is achieved through the following technical solutions:

The invention provides a method for preparing a superhydrophobic wear-resistant polypropylene coating, which specifically comprises the following steps:

(1) Pretreatment: Dissolve the silane coupling agent containing hydrophobic groups in ethanol solution, then add inorganic nanoparticles to obtain mixed solution A, stir and react at 20-70°C for 10-600min, and wash to remove residual Silane coupling agent and drying to obtain pretreated inorganic nanoparticles;

(2) Embedding treatment: disperse the pretreated inorganic nanoparticles in xylene, heat-treat it to obtain a mixed solution B, then immerse the polypropylene test piece in the above mixed solution B for 10s-5min, and pull it quickly, Obtain the polypropylene surface pre-modification sample;

(3) Post-treatment: immerse the polypropylene surface pre-modified sample in the toluene solution of the chlorosilane coupling agent containing hydrophobic groups, react at 20-100°C for 10min-500min, take it out and dry it to obtain Superhydrophobic and abrasion-resistant polypropylene coating.

Preferably, the ethanol solution described in step (1) is a 95wt% ethanol aqueous solution; the mass fraction of the silane coupling agent containing hydrophobic groups in the mixed solution A is 0.1-20 wt%, and the mass fraction of the inorganic nanoparticles is 1-20wt%.

Preferably, the silane coupling agent containing hydrophobic groups is dodecyltrimethoxysilane, tetradecyltrimethoxysilane, hexadecyltrimethoxysilane, cetyltriethoxy Silane, Heptadecylfluorodecyltrimethoxysilane, Perfluorodecyltriethoxysilane, Dodecyltrichlorosilane, Hexadecylmethyldichlorosilane, Octadecyltrichlorosilane, Perfluorinated Any one or more of octyltrichlorosilane and perfluorododecyltrichlorosilane.

Preferably, the mass fraction of pretreated inorganic nanoparticles in the mixed liquid B in step (2) is 0.1-50 wt %; the temperature of the heat treatment is 50-135° C.

The present invention utilizes the hydrophobic inorganic nanoparticles treated with the silane coupling agent containing hydrophobic groups, disperses them in xylene, and heats them to 50-135° C., so that the polypropylene test piece is immersed in the above solution, and the The swelling of the surface is favorable for the embedding of the hydrophobic inorganic nanoparticles into the surface of the polypropylene matrix, thereby obtaining a firm inorganic nanoparticle-embedded polypropylene pre-modified surface coating.

Preferably, the mass fraction of the hydrophobic group-containing chlorosilane coupling agent in the toluene solution of the hydrophobic group-containing chlorosilane coupling agent in step (3) is 0.1-20 wt%.

More preferably, the chlorosilane coupling agent containing hydrophobic groups is dodecyltrichlorosilane, hexadecylmethyldichlorosilane, octadecyltrichlorosilane, perfluorooctyltrichlorosilane , any one or more of perfluorododecyltrichlorosilane.

The present invention immerses the polypropylene surface pre-modified sample prepared in step (2) into the toluene solution of the chlorosilane coupling agent containing hydrophobic groups, utilizes the high reactivity of the chlorosilane coupling agent and its interaction with the pretreated The reaction between silane coupling agents on the surface of inorganic nanoparticles further introduces hydrophobic groups on the surface of polypropylene, and finally obtains a superhydrophobic and wear-resistant polypropylene coating. This post-treatment step also strengthens the firmness of inorganic nanoparticles and abrasion resistance.

Preferably, the inorganic nanoparticles are nano silicon dioxide or nano titanium dioxide.

The invention also provides a super-hydrophobic wear-resistant polypropylene coating prepared by the method.

Compared with the prior art, the present invention has the following effects:

1. The present invention uses a silane coupling agent containing hydrophobic groups to pretreat inorganic nanoparticles, and disperses them in xylene, and then immerses the polypropylene test piece in the above solution to make the surface of the polypropylene matrix swell, which is conducive to pretreatment The final hydrophobic inorganic nanoparticles are embedded in the surface of the polypropylene matrix to obtain a firm inorganic nanoparticle-embedded polypropylene pre-modified surface coating; and then immersed in the toluene solution of the chlorosilane coupling agent containing hydrophobic groups. reaction, further introducing hydrophobic groups on the surface of polypropylene, and finally obtaining a superhydrophobic and wear-resistant polypropylene coating. This post-treatment step also strengthens the firmness and wear resistance of inorganic nanoparticles.

2. The operation steps of the present invention are simple. It only needs to immerse the polypropylene test piece into the corresponding solution to obtain a super-hydrophobic and wear-resistant polypropylene coating, instead of using sandpaper on the surface of polypropylene as in the prior art. Complicated operations such as grinding to obtain the microstructure, and then performing UV/ozone treatment on the microstructure also avoid problems such as easy decomposition and non-wear resistance when using low surface energy.

3. The contact angle of water on the surface of the superhydrophobic wear-resistant polypropylene coating obtained in the present invention can reach 130-140°, the rolling angle is lower than 10°, and after the friction resistance test, the contact angle remains above 130°, which has Good wear stability.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Apparently, the described embodiments are only some of the embodiments of the present invention, not all of them. The following description of at least one exemplary embodiment is merely illustrative in nature and in no way taken as limiting the invention, its application or uses. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The numerical values set forth in these examples do not limit the scope of the invention unless specifically stated otherwise. Techniques and methods known to those of ordinary skill in the related art may not be discussed in detail, but under appropriate circumstances, the techniques and methods should be regarded as a part of the specification. In all examples shown and discussed herein, any specific values should be construed as illustrative only, and not as limiting. Therefore, other examples of the exemplary embodiment may have different values.

Example 1

A preparation method for a superhydrophobic wear-resistant polypropylene coating, comprising the steps of:

(1) Pretreatment: Dissolve dodecyltrimethoxysilane (silane coupling agent containing hydrophobic groups) in 95wt% ethanol solution, then add nano silicon dioxide to obtain mixed solution A, at 40°C Stir and react for 30 minutes, wash with water to remove residual silane coupling agent, and dry to obtain pretreated nano-silica particles;

Wherein, the mass fraction of dodecyltrimethoxysilane in the mixed solution A is 1 wt%, and the mass fraction of nano silicon dioxide is 5 wt%.

(2) Embedding treatment: disperse the pretreated nano-silica particles in xylene, heat it to 120°C to obtain a mixed solution B, and then immerse the surface-cleaned polypropylene test piece into the above mixed solution B Middle 3min, rapid pulling, to obtain the polypropylene surface pre-modified sample;

The mass fraction of the pretreated nano silicon dioxide particles in the mixed solution B is 10wt%.

(3) Post-treatment: immerse the polypropylene surface pre-modified sample in a toluene solution with a mass fraction of 1% of dodecyltrichlorosilane (chlorosilane coupling agent containing hydrophobic groups), and react at a temperature of 30°C After 30 minutes, take it out and let it dry to obtain a super-hydrophobic and wear-resistant polypropylene coating.

Example 2

A preparation method for a superhydrophobic wear-resistant polypropylene coating, comprising the steps of:

(1) Pretreatment: Dissolve hexadecyltriethoxysilane (silane coupling agent containing hydrophobic groups) in 95wt% ethanol solution, then add nano-titanium dioxide to obtain mixed solution A, at a temperature of 60°C Stirring and reacting for 60 minutes, washing with water to remove residual silane coupling agent, and drying to obtain pretreated nano-titanium dioxide particles;

Wherein, the mass fraction of hexadecyltriethoxysilane in the mixed liquid A is 6 wt%, and the mass fraction of nano-titanium dioxide is 10 wt%.

(2) Embedding treatment: disperse the pretreated nano-titanium dioxide particles in xylene, heat it to 130°C to obtain a mixed solution B, and then immerse the surface-cleaned polypropylene test piece in the above mixed solution B for 1 min , quickly pulled to obtain the polypropylene surface pre-modified sample;

The mass fraction of pretreated nano-titanium dioxide particles in the mixed solution B is 15 wt%.

(3) Post-treatment: immerse the polypropylene surface pre-modified sample in a toluene solution with a mass fraction of 5% perfluorooctyltrichlorosilane (chlorosilane coupling agent containing hydrophobic groups), and react at a temperature of 50°C After 60 minutes, take it out and let it dry to obtain a super-hydrophobic and wear-resistant polypropylene coating.

Example 3

A preparation method for a superhydrophobic wear-resistant polypropylene coating, comprising the steps of:

(1) Pretreatment: Dissolve heptadecafluorodecyltrimethoxysilane (silane coupling agent containing hydrophobic groups) in 95wt% ethanol solution, then add nano-silica to obtain mixed solution A, at 50°C Stir and react at high temperature for 100 minutes, wash with water to remove residual silane coupling agent, and dry to obtain pretreated nano-silica particles;

Wherein, the mass fraction of heptadecafluorodecyltrimethoxysilane in the mixed solution A is 10 wt%, and the mass fraction of nano silicon dioxide is 15 wt%.

(2) Embedding treatment: disperse the pretreated nano-silica particles in xylene, heat it to 125°C to obtain a mixed solution B, and then immerse the surface-cleaned polypropylene test piece into the above mixed solution B Middle 2min, rapid pulling, to obtain the polypropylene surface pre-modified sample;

The mass fraction of pretreated nano silicon dioxide particles in the mixed solution B is 20wt%.

(3) Post-treatment: immerse the polypropylene surface pre-modified sample in a toluene solution with a mass fraction of 10% of hexadecylmethyldichlorosilane (a chlorosilane coupling agent containing hydrophobic groups), at a temperature of 60°C After reacting for 10 minutes, take it out and dry it in the air to obtain a super-hydrophobic and wear-resistant polypropylene coating.

Example 4

A preparation method for a superhydrophobic wear-resistant polypropylene coating, comprising the steps of:

(1) Pretreatment: Dissolve perfluorododecyltrichlorosilane (silane coupling agent containing hydrophobic groups) in 95wt% ethanol solution, then add nano silicon dioxide to obtain mixed solution A, at 70°C Stir and react at high temperature for 10 minutes, wash with water to remove residual silane coupling agent, and dry to obtain pretreated nano-silica particles;

Wherein, the mass fraction of perfluorododecyltrichlorosilane in the mixed solution A is 20 wt%, and the mass fraction of nano silicon dioxide is 20 wt%.

(2) Embedding treatment: disperse the pretreated nano-silica particles in xylene, heat it to 50°C to obtain a mixed solution B, and then immerse the surface-cleaned polypropylene test piece into the above mixed solution B Middle 10s, rapid pulling, to obtain the polypropylene surface pre-modified sample;

The mass fraction of the pretreated nano silicon dioxide particles in the mixed solution B is 40wt%.

(3) Post-treatment: immerse the polypropylene surface pre-modified sample in a toluene solution with a mass fraction of 20% of octadecyltrichlorosilane (chlorosilane coupling agent containing hydrophobic groups), and react at a temperature of 100°C After 200 minutes, take it out and let it dry to obtain a super-hydrophobic and wear-resistant polypropylene coating.

Example 5

A preparation method for a superhydrophobic wear-resistant polypropylene coating, comprising the steps of:

(1) Pretreatment: Dissolve dodecyltrichlorosilane (silane coupling agent containing hydrophobic groups) in 95wt% ethanol solution, then add nano-titanium dioxide to obtain mixed solution A, stir and react at 20°C 300min, wash with water to remove residual silane coupling agent, and dry to obtain pretreated nano-titanium dioxide particles;

Wherein, the mass fraction of dodecyltrichlorosilane in the mixed liquid A is 0.1 wt%, and the mass fraction of nano titanium dioxide is 1 wt%.

(2) Embedding treatment: disperse the pretreated nano-titanium dioxide particles in xylene, heat it to 135°C to obtain a mixed solution B, and then immerse the surface-cleaned polypropylene test piece in the above mixed solution B for 5 minutes , quickly pulled to obtain the polypropylene surface pre-modified sample;

The mass fraction of pretreated nano-titanium dioxide particles in the mixed solution B is 0.1 wt%.

(3) Post-treatment: immerse the polypropylene surface pre-modified sample in a toluene solution with a mass fraction of 0.1% of perfluorododecyltrichlorosilane (a chlorosilane coupling agent containing a hydrophobic group) at a temperature of 20 ° C. After reacting for 10 minutes, take it out and dry it in the air to obtain a super-hydrophobic and wear-resistant polypropylene coating.

The contact angle of water on the surface of the superhydrophobic wear-resistant polypropylene coating obtained in the above examples 1-5 can reach 130-140°, the rolling angle is lower than 10°, and after the friction resistance test, the contact angle remains above 130° , has good wear stability.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (8)

1. a preparation method of superhydrophobic wear-resistant polypropylene coating, is characterized in that, comprises the steps: (1) Pretreatment: dissolve the silane coupling agent containing hydrophobic groups in ethanol solution, then add inorganic nanoparticles to obtain mixed solution A, stir and react at 20-70°C for 10-600min, wash and dry, Obtain the pretreated inorganic nanoparticles; (2) Embedding treatment: disperse the pretreated inorganic nanoparticles in xylene, heat-treat it to obtain a mixed solution B, then immerse the polypropylene test piece in the above mixed solution B for 10s-5min, and pull it quickly, Obtain the polypropylene surface pre-modification sample; (3) Post-treatment: immerse the polypropylene surface pre-modified sample in the toluene solution of the chlorosilane coupling agent containing hydrophobic groups, react at 20-100°C for 10min-500min, take it out and dry it to obtain Superhydrophobic and abrasion-resistant polypropylene coating. 2. the preparation method of a kind of superhydrophobic wear-resistant polypropylene coating according to claim 1 is characterized in that, the ethanol solution described in the step (1) is the aqueous ethanol solution of 95wt%; The mass fraction of the hydrophobic group silane coupling agent is 0.1-20 wt%, and the mass fraction of the inorganic nanoparticles is 1-20 wt%. 3. the preparation method of a kind of superhydrophobic wear-resistant polypropylene coating according to claim 1 and 2 is characterized in that, the silane coupling agent containing hydrophobic group is dodecyltrimethoxysilane, Tetradecyltrimethoxysilane, Hexadecyltrimethoxysilane, Hexadecyltriethoxysilane, Heptadecyltrimethoxysilane, Perfluorodecyltriethoxysilane, Dodecyltriethoxysilane Any one or more of alkyltrichlorosilane, hexadecylmethyldichlorosilane, octadecyltrichlorosilane, perfluorooctyltrichlorosilane, perfluorododecyltrichlorosilane. 4. the preparation method of a kind of superhydrophobic wear-resistant polypropylene coating according to claim 1 is characterized in that, the massfraction of the pretreated inorganic nanoparticles in the mixed solution B described in step (2) is 0.1 -50wt%; the temperature of the heat treatment is 50-135°C. 5. the preparation method of a kind of superhydrophobic wear-resistant polypropylene coating according to claim 1 is characterized in that, the toluene solution containing the chlorosilane coupling agent of hydrophobic group described in step (3) contains hydrophobic The mass fraction of the group chlorosilane coupling agent is 0.1-20wt%. 6. according to the preparation method of a kind of superhydrophobic wear-resistant polypropylene coating described in claim 1 or 5, it is characterized in that, the chlorosilane coupling agent containing hydrophobic group is dodecyltrichlorosilane, Any one or more of hexadecylmethyldichlorosilane, octadecyltrichlorosilane, perfluorooctyltrichlorosilane, and perfluorododecyltrichlorosilane. 7. the preparation method of a kind of superhydrophobic wear-resistant polypropylene coating according to claim 1, is characterized in that, described inorganic nano-particle is nano-silica or nano-titanium dioxide. 8. A superhydrophobic wear-resistant polypropylene coating prepared by the method described in any one of claims 1-7.