CN105001438A - Method for modification of polyurethane film for protective glass - Google Patents

Abstract

The invention relates to material surface modification technology and aims to provide a method for modifying polyurethane film for protective glass. Including: mixing silane coupling agent KH550, deionized water and absolute ethanol to obtain a dilute solution of silane coupling agent KH550; then stirring at 30°C for 8 hours to fully hydrolyze; put the washed and dried polyurethane film into it , ultrasonic treatment at 30° C. for 1 to 10 minutes; take out the polyurethane film, wash and dry it, and obtain a surface-modified polyurethane film. Compared with the original polyurethane film, the light transmittance of the modified polyurethane film is greatly improved, and the contact angle of the film surface is significantly reduced, that is, the surface tension is increased and the surface wetting ability is enhanced. The bonding strength is improved, and the light transmittance of the protective glass compounded with the modified film is improved. The invention has the advantages of simple and practical operation, low cost and easy application in production practice; it can be used to improve the organic-inorganic bonding strength of composite glass.

Description

A kind of modification method of polyurethane film for protective glass

technical field

The invention belongs to the technical field of material surface modification and protective glass, and in particular relates to a modification process of polyurethane (PU) film for protective glass. Polyurethane film.

Background technique

Protective glass refers to a transparent material that has the light transmission properties of glass and has a certain protective ability. The protective principle is that the glass converts the impact kinetic energy into the elastic potential energy of the glass and the broken surface energy, so as to achieve the purpose of protection. It has played an important role in protection, military and police protection, and ensuring the safety of aerospace and financial activities. In addition, with the development of social economy and the continuous improvement of public security awareness, protective glass has begun to penetrate into various industries of social life such as finance and transportation, and the demand for civilian protective glass is also growing.

From a structural point of view, protective glass can be divided into tempered glass, laminated glass, composite glass and film glass. Among them, the composite glass uses inorganic glass (G) as the panel material, polyurethane (PU) as the intermediate buffer and adhesive layer, and polycarbonate (PC) as the back sheet material, that is, Glass/PU/PC protective structure. By comparing the impact resistance, weather resistance, thermal stability and other properties of protective glass with different structures, the comprehensive performance of composite glass is better.

Polyurethane (PU) refers to a macromolecular compound containing urethane group (—NH—COO—) or isocyanate group (—NCO) in its molecular chain, mainly composed of dibasic or polyisocyanate, and containing two or more active hydrogens. Compounds that are polymerized by stepwise polymerization. Polyurethane film has good wear resistance, low temperature resistance and thermal stability, and is the best film choice for organic-inorganic composite protective glass. But on the other hand, the surface activity of the film itself is low, and its adhesive performance needs to be further improved.

For the surface modification of polyurethane, the method can be divided into cross-linking modification, copolymerization modification, blending modification and compound modification four kinds, the present invention uses silane coupling agent solution to modify the surface of polyurethane film, improve the film The bonding strength also improves the performance of the polyurethane film as the intermediate bonding layer of composite glass.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a method for modifying polyurethane film for protective glass. The solution is mainly used to ultrasonically treat the polyurethane film to improve the adhesive performance of the polyurethane film.

For solving technical problem, solution of the present invention is:

A method for modifying a polyurethane film for protective glass is provided, comprising the following steps:

(1) Silane coupling agent KH550, deionized water and dehydrated alcohol are mixed to obtain silane coupling agent KH550 dilute solution; with silane coupling agent KH550 dilute solution being 100 parts by weight, the proportioning relationship of the three materials is :

Silane coupling agent KH550 1.3～1.7 parts by weight

Deionized water 3.3～3.7 parts by weight

Absolute ethanol 95 parts by weight

(2) Stir the dilute solution of silane coupling agent KH550 at 30°C for 8 hours to fully hydrolyze the silane coupling agent KH550;

(3) Put the cleaned and dried polyurethane film into the dilute solution of hydrolyzed silane coupling agent KH550, and ultrasonically treat it at 30°C for 1-10 minutes;

(4) Take out the polyurethane film, wash and dry to obtain a surface-modified polyurethane film.

In the present invention, the stirring in the step (2) is magnetic stirring, and the rotating speed is 500 rpm.

In the present invention, the washing and drying in the step (3) refers to: putting the polyurethane film into absolute ethanol and deionized water for 15 minutes to ultrasonically clean it respectively, and then drying it in an oven at 40°C.

In the present invention, the cleaning and drying in the step (4) refers to: ultrasonically cleaning the modified polyurethane film in deionized water for 30 minutes, and finally drying in an oven at 40°C.

Compared with prior art, the beneficial effect of the present invention is:

(1) Compared with the original polyurethane film, the modified polyurethane film of the present invention has a greatly improved light transmittance, and a significant decrease in the contact angle on the surface of the film, that is, the surface tension increases and the surface wettability increases.

(2) The bonding strength of the modified polyurethane film of the present invention is improved, and the light transmittance of the protective glass obtained by compounding the modified film is improved.

(3) The present invention can be used to improve the organic-inorganic bonding strength of composite glass (Glass/PU/PC), mainly aimed at improving the bonding performance of the polyurethane (PU) film used. Compared with other modification methods, the improved method of the present invention is simple and practical in operation, low in cost and easy to apply in production practice.

Description of drawings

Fig. 1 is the light transmittance of the polyurethane film obtained in Examples 1, 2, and 3 of the present invention and the original polyurethane film.

Fig. 2 is the light transmittance of the composite glass obtained in Examples 1, 2 and 3 of the present invention and the original film composite glass.

Detailed ways

Example 1

Polyurethane (PU) films were cut into 30 mm × 10 mm, put into absolute ethanol and deionized water and ultrasonically cleaned for 15 min, respectively, and the films were taken out, placed on petri dishes, and dried in an oven at 40 °C.

Use a balance to weigh the silane coupling agent KH550, absolute ethanol and deionized water according to the proportions of 1.3wt%, 95%, and 3.7wt%, respectively, and seal them in a beaker at a temperature of 30°C. Stir for 8 hours at a speed of 500 rpm to fully hydrolyze the coupling agent.

Put the washed and dried PU film into the dilute solution of hydrolyzed silane coupling agent KH550, and ultrasonically treat it for 1min at a temperature of 30°C. The treated film is ultrasonically cleaned with deionized water for 30min, and placed in an oven at 40°C. Medium dry.

Use the obtained PU film to bond with glass and polycarbonate (PC) to test the sample, place it in a vacuum oven at 120°C and a vacuum of 0.1MPa for 6 hours, and perform a bond strength test on a universal testing machine.

The protective glass (Glass/PU/PC) and the modified PU film were prepared by compounding the obtained PU, and the light transmittance test was carried out.

Example 2

Polyurethane (PU) films were cut into 30 mm × 10 mm, put into absolute ethanol and deionized water and ultrasonically cleaned for 15 min, respectively, and the films were taken out, placed on petri dishes, and dried in an oven at 40 °C.

Use a balance to weigh the silane coupling agent KH550, absolute ethanol and deionized water according to the proportions of 1.5wt%, 95%, and 3.5wt%, respectively, and place them in a sealed beaker at a temperature of 30°C. Stir for 8 hours at a speed of 500 rpm to fully hydrolyze the coupling agent.

Put the washed and dried PU film into the dilute solution of hydrolyzed silane coupling agent KH550, and ultrasonically treat it for 5 minutes at a temperature of 30°C, then ultrasonically clean the treated film with deionized water for 30 minutes, and place it at 40°C Dry in the oven.

Use the obtained PU film to bond with glass and polycarbonate (PC) to test the sample, place it in a vacuum oven at 120°C and a vacuum of 0.1MPa for 6 hours, and perform a bond strength test on a universal testing machine.

The protective glass (Glass/PU/PC) and the modified PU film were prepared by compounding the obtained PU, and the light transmittance test was carried out.

Example 3

Polyurethane (PU) films were cut into 30 mm × 10 mm, put into absolute ethanol and deionized water and ultrasonically cleaned for 15 min, respectively, and the films were taken out, placed on petri dishes, and dried in an oven at 40 °C.

Use a balance to weigh a certain amount of silane coupling agent KH550, absolute ethanol and deionized water according to the weight fraction of 1.7wt%, 95% and 3.3wt%, and place them in a sealed beaker at a temperature of 30°C. Under magnetic stirring for 8 hours, the rotation speed is 500rpm, so that the coupling agent is fully hydrolyzed.

Put the washed and dried PU film into the dilute solution of hydrolyzed silane coupling agent KH550, and ultrasonically treat it for 10 minutes at a temperature of 30°C, then ultrasonically clean the treated film with deionized water for 30 minutes, and place it at 40°C Dry in oven.

Use the obtained PU film to bond with glass and polycarbonate (PC) to test the sample, place it in a vacuum oven at 120°C and a vacuum of 0.1MPa for 6 hours, and perform a bond strength test on a universal testing machine.

The protective glass (Glass/PU/PC) and the modified PU film were prepared by compounding the obtained PU, and the light transmittance test was carried out.

Table 1 shows the bonding strength between the polyurethane film obtained in Examples 1, 2 and 3 of the present invention and the original polyurethane film.

testing sample Adhesive maximum force/N Adhesive strength/MPa Original film 607 2.03 Example 1 1240 4.13 Example 2 1270 4.23 Example 3 900 3.00

It can be seen from the table that the bonding strength of the original polyurethane film is 2.03MPa, while the bonding strength of the modified polyurethane film has increased to 4.23MPa, an increase of nearly 110%. Therefore, it can be concluded that by adopting the method of the present invention to process the polyurethane film, the organic-inorganic bonding strength of the film to glass and PC has been significantly improved.

Claims (4)

1. a modification method of polyurethane film for protective glass, is characterized in that, comprises the following steps: (1) Silane coupling agent KH550, deionized water and dehydrated alcohol are mixed to obtain silane coupling agent KH550 dilute solution; with silane coupling agent KH550 dilute solution being 100 parts by weight, the proportioning relationship of the three materials is : Silane coupling agent KH550 1.3～1.7 parts by weight Deionized water 3.3～3.7 parts by weight Absolute ethanol 95 parts by weight (2) Stir the dilute solution of silane coupling agent KH550 at 30°C for 8 hours to fully hydrolyze the silane coupling agent KH550; (3) Put the cleaned and dried polyurethane film into the dilute solution of hydrolyzed silane coupling agent KH550, and ultrasonically treat it at 30°C for 1-10 minutes; (4) Take out the polyurethane film, wash and dry to obtain a surface-modified polyurethane film. 2. The method according to claim 1, characterized in that, the stirring in the step (2) is magnetic stirring, and the rotating speed is 500rpm. 3. The method according to claim 1, characterized in that, the washing and drying in the step (3) refers to: putting the polyurethane film into absolute ethanol and deionized water for ultrasonic cleaning respectively for 15min, and then placing Dry in an oven at 40°C. 4. The method according to claim 1, characterized in that, the cleaning and drying in the step (4) refers to: placing the modified polyurethane film in deionized water for ultrasonic cleaning for 30min, and finally placing it in Dry in an oven at 40°C.