The effect of seasonal changes on the use of adhesive tape
(Popularity:2041)
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times：2019-02-13
The pressure-sensitive adhesive has special viscoelasticity and produces viscosity under the action of external force, thereby achieving close contact with the object to be adhered, and moisturizing and penetrating the surface of the object to be adhered, and the adhesive molecules and the adherend molecules are close to 5×10. Within -10m, Van der Waals forces are generated to form a paste. From this we can see that the adhesive exerts two elements of its adhesive force: the viscoelasticity of the adhesive and the external force. The viscoelasticity of the adhesive is mainly related to the variety of the adhesive elastomer and its formulation. It is the main and intrinsic element. The external force includes the use environment of the tape (temperature, humidity), the pasting method and the pasting size, the material of the adherent object and Surface cleanliness, surface shape, etc. are external factors. Only the effects of temperature and humidity on the use of pressure-sensitive adhesive tapes are discussed here.
1. the impact of temperature
The viscosity of the pressure-sensitive adhesive tape is mainly produced by an adhesive. Adhesive (refers to the adhesive that has been made into tape, the same below) is a semi-fluid, there is irregular molecular motion (ie Brownian motion) inside, the temperature rises, the intermolecular force decreases, the Brownian motion strengthens, the pair is The wetting and permeation of the sticky object is easy, and the viscosity is good. At the same time, the temperature increases, the energy of the surface of the adherent object is active, and the binding force with the adhesive molecules is strengthened, and the sticking is firm, which is when our common temperature is high. The reason why the tape is sticky. However, when the temperature is higher than a certain limit, the force between the molecules of the adhesive is greatly reduced, and the molecules are liable to lose the "binding", which will result in the phenomenon of "high temperature flow glue". On the contrary, when the temperature is lowered, the energy of the adhesive molecules is reduced, the Brownian motion of the adhesive molecules is weakened, the "introtropy" of the adhesive is enhanced, and the molecular activity of the adherent object is decreased when the temperature is lowered, and between the adhesive molecules and the molecules to be adhered. The van der Waals force is reduced and the tape viscosity is reduced; when the temperature is lowered to the glass transition temperature of the adhesive, the tape loses its viscosity, which is the phenomenon of "low temperature loss of stickiness".
In addition, as the temperature rises and the thermal creep of the adhesive rises, it can be broadly understood that the glue melts, and the temperature rise accelerates the aging of the adhesive and reduces the viscosity of the adhesive.
2. the impact of humidity
The suitable humidity for pressure-sensitive adhesive tape is about 55%~80% RH. When it is more than 80% (such as the rainy season), the tape (especially water gel) contains a small amount of solvent or moisture, which is not easy to disperse, and covers part of the adhesive tape. Viscous, the surface of the object to be adhered also adsorbs moisture to form a weak interface, which reduces the viscosity of the tape. When the relative humidity is lower than 55% (such as dry and cold in winter), the adhesive and the object to be adhered are too dry, which hinders the wetting and infiltration process of the adhesive; when the humidity is lowered, the dust concentration in the air will rise, and the weak interface is easily generated when pasting. , affecting the adhesive to exert its viscosity. Therefore, whether the humidity is too high or too low, the adhesive will be reduced in viscosity.
After mid-September, most of China will enter the autumn and winter seasons. The main features of the autumn and winter weather are air drying and a significant drop in temperature. From the above analysis, we know that the use of pressure-sensitive adhesive tapes this season will make the tape less sticky and difficult to paste, and it is necessary to produce and sell at the same time to overcome the adverse effects of seasonal changes on the use of the tape.
1. The factory should adjust the formulation of the adhesive according to the seasonal changes. This is a proactive measure.
2. the sales staff should understand the adverse effects of seasonal changes on the use of tape, promptly explain to customers, and assist customers to improve the environmental conditions of production, storage, etc., such as heating and humidification, to facilitate the tape Normally play its performance.
1. the impact of temperature
The viscosity of the pressure-sensitive adhesive tape is mainly produced by an adhesive. Adhesive (refers to the adhesive that has been made into tape, the same below) is a semi-fluid, there is irregular molecular motion (ie Brownian motion) inside, the temperature rises, the intermolecular force decreases, the Brownian motion strengthens, the pair is The wetting and permeation of the sticky object is easy, and the viscosity is good. At the same time, the temperature increases, the energy of the surface of the adherent object is active, and the binding force with the adhesive molecules is strengthened, and the sticking is firm, which is when our common temperature is high. The reason why the tape is sticky. However, when the temperature is higher than a certain limit, the force between the molecules of the adhesive is greatly reduced, and the molecules are liable to lose the "binding", which will result in the phenomenon of "high temperature flow glue". On the contrary, when the temperature is lowered, the energy of the adhesive molecules is reduced, the Brownian motion of the adhesive molecules is weakened, the "introtropy" of the adhesive is enhanced, and the molecular activity of the adherent object is decreased when the temperature is lowered, and between the adhesive molecules and the molecules to be adhered. The van der Waals force is reduced and the tape viscosity is reduced; when the temperature is lowered to the glass transition temperature of the adhesive, the tape loses its viscosity, which is the phenomenon of "low temperature loss of stickiness".
In addition, as the temperature rises and the thermal creep of the adhesive rises, it can be broadly understood that the glue melts, and the temperature rise accelerates the aging of the adhesive and reduces the viscosity of the adhesive.
2. the impact of humidity
The suitable humidity for pressure-sensitive adhesive tape is about 55%~80% RH. When it is more than 80% (such as the rainy season), the tape (especially water gel) contains a small amount of solvent or moisture, which is not easy to disperse, and covers part of the adhesive tape. Viscous, the surface of the object to be adhered also adsorbs moisture to form a weak interface, which reduces the viscosity of the tape. When the relative humidity is lower than 55% (such as dry and cold in winter), the adhesive and the object to be adhered are too dry, which hinders the wetting and infiltration process of the adhesive; when the humidity is lowered, the dust concentration in the air will rise, and the weak interface is easily generated when pasting. , affecting the adhesive to exert its viscosity. Therefore, whether the humidity is too high or too low, the adhesive will be reduced in viscosity.
After mid-September, most of China will enter the autumn and winter seasons. The main features of the autumn and winter weather are air drying and a significant drop in temperature. From the above analysis, we know that the use of pressure-sensitive adhesive tapes this season will make the tape less sticky and difficult to paste, and it is necessary to produce and sell at the same time to overcome the adverse effects of seasonal changes on the use of the tape.
1. The factory should adjust the formulation of the adhesive according to the seasonal changes. This is a proactive measure.
2. the sales staff should understand the adverse effects of seasonal changes on the use of tape, promptly explain to customers, and assist customers to improve the environmental conditions of production, storage, etc., such as heating and humidification, to facilitate the tape Normally play its performance.