The degumming and gelatinization temperature of co

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Did the degumming and gelatinization temperature of corrugated board not be adjusted well in winter

in fact, winter is not only the season of cardboard bursting, but also the high incidence period of cardboard degumming. To keep the board from degumming, let's talk about the control of gelatinization temperature when making glue

what is gelatinization and gelatinization temperature

definition of gelatinization: the phenomenon that starch turns into translucent colloid under certain conditions after being heated with water. After the starch is heated, within a certain temperature range, the starch granules begin to destroy, the crystal structure disappears, the volume expands, the viscosity rises sharply, and it becomes a sticky paste, that is, it becomes an amorphous starch

the temperature at which starch gelatinizes is called gelatinization temperature. The gelatinization temperature of starch varies with the type of raw materials and the size of starch granules

take an example, because many factories do not pay enough attention to the gelatinization temperature when making glue. It is a formula all year round, and the gelatinization temperature has not changed

if the gelatinization temperature of a factory is 58 degrees in summer, it is still 58 degrees in winter, and it is still OK in summer, but problems occur in winter. The speed is not fast, the baking time of the cardboard increases, and the moisture loss of the cardboard is large, resulting in the cardboard burst, but as soon as the speed is fast, the cardboard degumms, which means that the gelatinization temperature is too high

expert tips

since the reason for degumming in winter is the problem of gelatinization temperature, then 3. The forced lubrication mechanism of the oil pump of the spring tension and compression fatigue experimental machine: is it possible to work at high frequency, it is the most important to understand the index of gelatinization temperature

in winter, the gelatinization temperature must be low, because the temperature of the equipment and paper is easy to volatilize in winter, and the temperature value of the paper will be reduced when the experiment is not carried out for a long time. Therefore, when making paste, the gelatinization temperature should be low, which is generally recommended, which is conducive to the adhesion of the paste. Thus, the reduction of vehicle speed and the additional occurrence of paperboard bonding and degumming are avoided

in summer, the gelatinization temperature can be a little higher, such as degrees, because the temperature loss of the equipment is relatively small in summer, and secondly, the temperature of the paper is relatively fast, so the gelatinization temperature in summer should not be too low, otherwise there will be false bonding. It means that the paste can't be used for data input and output without a printer

we have learned the control of gelatinization temperature, and we also need to master the detection method of gelatinization temperature

detection of gelatinization temperature

to detect the gelatinization temperature, put the sample into the test tube, put the sample in half of the test tube, invade the test tube into a hot water bath above 77 ℃, stir it with a thermometer, and when the sample is too viscous to stir and the temperature stops rising, record this temperature, which is the gelatinization temperature of the adhesive

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