Preparation and application principle II of the ho

Preparation and use principle of carton starch adhesive II

II. Use

(I) several factors affecting the quality of adhesive

1. The viscosity

is also the performance of the initial viscosity of the adhesive. The initial viscosity directly affects the adhesion of corrugated board. Therefore, the quality control of the adhesive can be reflected in "viscosity"

(1) viscosity and temperature

temperature (℃) 556065

viscosity (initial) 5065140

a certain temperature is required for the full swelling of starch granules. The proportion of exports to emerging countries will also be greatly increased, which is mainly provided by heating and caustic soda solution. Therefore, in order to make the viscosity of adhesives appropriate, attention must be paid to the control of water temperature and the amount of caustic soda added

(2) borax and viscosity

borax (kg) 1.8 2

viscosity (SEC) 60 100

the amount of borax is also a factor affecting viscosity. In practical application, it must be appropriate and small, so that the adhesive is too thin and easy to penetrate into the paper, causing corrugated board to run off and collapse; Large dosage will make the adhesive become rubber like and lose adhesion

viscosity adjustment method:

when the viscosity is high, the starch content in the carrier can be appropriately reduced

2. Ripening temperature

the temperature at which the starch adhesive begins to thicken and shows its adhesive properties due to the gradual ripening of raw starch in the adhesive raw materials

due to different starch or different starch quality, the ripening temperature is different. Therefore, it is necessary to adjust the heating temperature in actual operation, mainly by increasing or decreasing the amount of caustic soda

3. Solid content in starch adhesive

measuring the solid content in adhesive is a method to judge the adhesive ability

common formula: g3-g1

solid content = one by one × 100%

g2 - g1

g1 - mass of aluminum weighing dish kg

g2 - mass of wet adhesive plus weighing dish, which is the most common equipment in the plastic mixing laboratory kg

g3 - mass of adhesive plus weighing dish after drying kg

4, pH value (acid, alkaline)

we know that starch granules contain certain fatty acids, which neutralize with caustic soda solution to form a weakly alkaline adhesive, Therefore, measuring the pH value of adhesive 1 is to promote the development and utilization of new materials in the plastic industry. We can know whether the reaction in the preparation process of adhesive is complete and how the quality of adhesive is

1 generally, it will not affect the experiment, and the pH value should be between

5. Equipment performance and other factors

during the preparation of adhesive, the influence of equipment performance, instruments, meters and other factors can not be ignored

(to be continued)