Application Research of Waterborne Polyurethane Adhesive (I)

Polyurethane adhesives are used more and more widely due to their advantages such as high adhesive strength, low temperature resistance, and good flexibility. However, at present, polyurethane adhesives are still mainly solvent-based, and they have more or less certain toxicity, which has a certain impact on the environment and human health. In recent years, the safety and hygienic nature of packaging, especially food packaging, has attracted more and more attention. At the same time, countries are paying more and more attention to environmental protection, prompting researchers to invest in research and development of environmentally friendly water-based adhesives. Beijing Gaomeng Chemical Co. Before the establishment of scientific research personnel to develop water-based adhesives, the waterborne polyurethane adhesives that have been put on the market include common plastic/plastic composite single-component adhesives (I)620 and boiled plastic/plastic composite two-component adhesives (YH610/YH05). This article will introduce the physical properties of these two adhesives and the use of precautions.

Experimental conditions and results analysis

1. Main raw materials

Adhesive: 1YH6 20 one-component waterborne polyurethane adhesive: 2YH610/Yh05 two-component waterborne polyurethane adhesive, with a ratio of YH610YH05=20:1.

Substrate: Transparent PE60, VMCPP, BOPP, PET, PA25.

2. Experimental equipment and instruments

H1ROSHlMA compounding machine (Japan), compound speed 60-1 20m/min BLD-200S electronic peeling tester.

3. Performance Testing

According to the GB2790-81 standard, the lower (90) peel strength of the composite film was measured and the peel rate was 300 mm/MIN.

4. Experimental results and analysis

(1) Effect of coating amount on peel strength

The quality of the composite film is closely related to the amount of adhesive applied. YH620 binder composite full-print printing is BOPP film and VMCPP film, the amount of coating on the composite film peel strength in Table 1. It can be seen from Table 1 that the dry base coating amount of YH620 adhesive should be 1.5Q/m2 or more.

The effect of the coating amount on the peel strength of the composite film is shown in Table 2 with YH610/YH05 composite films of PA/PE and PET/PE structures. It can be seen from Table 2 that the dry base coating amount of the YH610/YH05 adhesive should be 2.5-3.0 g/m2, and the dry base coating amount is increased, and the peel strength does not change much.

(2) Boilability of YH610/YH05 Adhesives

With YH610/YH05 composite PA/PA/PE, PET/PE, the dry base coating amount is experimental conditions and the results were analyzed 3.0-3.5g/m2, after 100 °C, 30mim boiling, changes in the composite film peel strength before and after boiling See Table 3 for comparison with solvent-based polyurethane adhesives.

It can be seen from Table 3 that the properties of YH610/YH05 and solvent-based polyurethane adhesives are close to each other and can meet the requirements of boiling water processing.