Application of the hottest alcohol soluble two-com

Application of alcohol soluble two-component polyurethane adhesive in composite film

summary: alcohol soluble two-component polyurethane adhesive is a new adhesive product for composite film independently developed by our unit in recent years. It has outstanding characteristics such as good adaptability to alcohol soluble ink, low residual solvent in laminating products, good performance of anti slippery agent, normal temperature curing, insensitive to humidity, and beneficial to environmental protection. Combined with the research progress of our unit, the development and future development trend of alcohol soluble two-component polyurethane adhesive are put forward

key words: alcohol soluble polyurethane adhesive two-component

I. preface [1, 2]

alcohol soluble two-component polyurethane adhesive is a new adhesive in the domestic composite film market in recent years. Its main features are:

1, good adaptability to alcohol soluble ink

2. The residual solvent of composite membrane products is low

3. The skid resistance agent has good performance, and the increase of friction coefficient after compounding is less. For films with high skid content, the adhesive strength attenuation after compounding is small

4. No need to heat and ripen to reduce energy consumption

5. Alcohol solvents are cheaper than ethyl acetate, reducing the use cost

6. It does not contain free isocyanate units, which improves the operating environment

7. It is insensitive to humidity, which improves the stability and adaptability of the adhesive

alcohol soluble two-component polyurethane adhesive can be used for composite bonding of plastic film/plastic film, plastic film/aluminized film, paper/plastic film and other material structures. Now domestic manufacturers mostly use it for light packaging of light flavor food. Due to the fierce social and economic market competition in China, alcohol soluble two-component polyurethane adhesive has gradually gained market attention because of its application characteristics and advantages in energy consumption and environmental protection

II. Product overview [1,2]

alcohol soluble two-component polyurethane adhesive is an environmental friendly composite film bonding material, which can be widely used in the composite and bonding process of plastic film, aluminized film, paper and other film products. It is mainly used in the food composite film packaging industry. It has excellent machine operability, and has good coating dispersion for a variety of materials. It can be used for bonding and compounding polyethylene, polypropylene, aluminized film, polyester, nylon and other film materials

at present, in order to meet the processability of the composite film and the openness of the finished product, many p determine whether the product reaches the strength grade by testing the strength. The production standard e film uses a smoothing agent. After multiple processes such as compounding and printing, the lubricant is often eroded to reduce its smoothness or even lose its smoothness. Alcohol soluble two-component polyurethane adhesive is specially designed to maintain high smoothness of the film and minimize the loss of smoothness agent. It is worth mentioning that in the case of composite films, the increase of temperature will improve the mobility of the lubricant in the film, and the lubricant must be on the surface of the film to play its role. The improvement of mobility will make the lubricant no longer stay on the surface of the film, but migrate to the bonding layer, which will cause the increase of friction coefficient and the decrease of bonding strength. Therefore, the minimum temperature at which the solvent can be completely removed should be maintained during the drying of the film

alcohol soluble two-component polyurethane adhesive should be added with curing agent in use. The proportion and dosage of the two components can be adjusted within a certain range. The stability of the two components is good, and they will not deteriorate under the influence of humidity in the air. They can be stored for a long time without changing the bonding performance of the adhesive. Compared with general polyurethane adhesives, alcohol soluble two-component polyurethane adhesives can be cured at room temperature, have ideal initial adhesion, and the later bonding strength is higher

alcohol soluble two-component polyurethane adhesive can be mixed with a variety of solvents including methanol, n-propanol, isopropanol, etc. in addition to being diluted with ethanol. At the same time, it can not be affected by the high humidity of the environment. The addition ratio of different solvents can also be adjusted according to the compounding needs to adapt to the compounding of the composite membrane. It is worth noting that ketones or solvents containing ketones are considered impure in the alcohol sol, because ketones such as MEK, etc. will cause odor to remain in the composite membrane. Therefore, ketones or solvents containing ketones cannot be used in composite food packaging

using ethanol as solvent has several outstanding advantages. First, its low price can greatly reduce the use cost; Second, it can optimize the working environment and reduce the damage to operators. Since ethanol is used as the solvent for the two-component soluble polyurethane adhesive, high temperature storage should be avoided, especially direct sunlight

III. The research results of our unit

alcohol soluble polyurethane adhesive was successfully developed and popularized abroad in the 1980s, while the development and research work in China is currently in its infancy. With the help of our own research and development experience and technical strength of polyurethane adhesive for many years, our unit has continuously tackled key technical problems. After years of efforts, we finally got through the technical route and obtained the target product. The brand of alcohol soluble two-component polyurethane adhesive studied and produced by our company is uf2870/uf9985e, and the corresponding indicators are shown in Table 1. It can be used when the solid content is diluted to 30 ~ 35% during composite processing, and the dry basis coating amount can be selected between 2-3.5g/m2. The composite film products are cured at room temperature, can be cut and bagged in 48 hours, and reach the maximum strength in 5 ~ 7 days. The initial peel strength of uf2870 adhesive for the composite of bopp/cpp, bopp/pe and other plastic films/plastic films can reach 2 ~ 3 N/15 mm, and the final peel strength can reach 4 ~ 5 N/15 mm; The composite of plastic film/plastic aluminum film such as bopp/aluminized film, printing film/aluminized film can also reach 2 n/15 mm. The manufacturer of this medical compound has 13 compound production lines, and the final peel strength reaches 3 N/15 mm. Then the sensor can be calibrated again to work normally, which can meet the relevant requirements. Refer to figure 1

IV. development significance of this product [3]

at present, with the vigorous development of China's economy and the continuous improvement of the quality of national life, the environmental protection problem of the composite film packaging industry has been paid more and more attention. The market needs more environmentally friendly composite adhesives, and alcohol soluble polyurethane adhesive is an environmentally friendly product to meet this demand

in recent years, polyurethane adhesives at home and abroad, like the whole adhesive and coating industry, have developed prominently to meet the requirements of policies and regulations in environmental protection, industrial health, resources and other aspects, adjust the industrial structure, and strive to reduce the proportion of organic solvent-based products. Advanced countries have formulated environmental protection regulations, requiring the development of pollution-free adhesives to minimize the use of solvents and the toxicity of solvents, However, solvent based adhesives have their own uniqueness, which can not be replaced in some occasions, so it is impossible to cancel them all in a short time. The solution is to choose low toxic solvents, improve the solid content of working fluid, operate in closed ventilation, and use solvent recovery devices. In recent years, Europe has put forward the concept of "green" solvents, that is, those solvents that are not toxic, some of which can even be biodegradable, and have been removed from the list of toxic release substances (TRI) and organic volatiles (VO operators only need to click the mouse c) such as ethanol. Polyurethane adhesives with these solvents suffer less environmental pressure

many cities in China now pay more and more attention to environmental protection, and pay more attention to the pollution of the composite film industry. Many composite manufacturers are eager to find less polluting adhesives for production, so as to reduce the pressure of environmental protection. Although the development of adhesives will eventually move towards solventless, because solventless adhesives require special solventless laminating machines and large equipment investment, they cannot be widely promoted in the mainland in the near future. Therefore, at present, alcohol soluble polyurethane adhesives can still become the mainstream products in the market

use alcohol soluble two-component polyurethane adhesive to remove the advantages of environmental protection. Another main feature is that it can reduce the use cost. The current price of ethanol in the domestic market is lower than that of ethyl acetate, and this adhesive can be cured at room temperature to reduce energy consumption, which is conducive to reducing costs

the promotion and marketing of our alcohol soluble two-component polyurethane adhesive has just begun, and the actual application experience is still relatively small. However, we believe that with the cooperation and assistance of the majority of manufacturers, alcohol soluble two-component polyurethane adhesive will be widely used in the composite film industry. The composite membrane industry has entered a new stage of development

Author: Wang Yongjiang, Zhang Jianhua, Li Wei

from: (Beijing Chemical Industry Research Institute branch)