阅读说明：本技术 一种提高包装用胶水黏度及稳定性的方法 (Method for improving viscosity and stability of glue for packaging ) 是由 雷勇 陈士一 于 2019-11-29 设计创作，主要内容包括：本发明公开了一种提高包装用胶水黏度及稳定性的方法,所述胶水是用水、玉米淀粉、烧碱水、稳定剂、硼砂、架桥剂这些原料进行配制的,并控制稳定剂和硼砂的加入时机：必须满足在将水、玉米淀粉及烧碱水三者依次混合均匀后,用涂四杯测定其浓度达到20-22S后才能加入。本发明通过在恰当的时机加入稳定剂及硼砂,能够在将配制的胶水初粘达到7.5N/cm2。(The invention discloses a method for improving the viscosity and stability of glue for packaging, wherein the glue is prepared from the following raw materials of water, corn starch, caustic soda, a stabilizer, borax and a bridging agent, and the adding time of the stabilizer and the borax is controlled as follows: the water, the corn starch and the caustic soda water are mixed evenly in sequence and added after the concentration of the mixture is measured to reach 20-22S by coating four cups. According to the invention, the stabilizer and the borax are added at a proper time, so that the initial adhesion of the prepared glue can reach 7.5N/cm.)

1. The method for improving the viscosity and stability of the glue for packaging is characterized in that the glue is prepared from the following raw materials of water, corn starch, caustic soda, a stabilizer, borax and a bridging agent, and the adding time of the stabilizer and the borax is controlled: the water, the corn starch and the caustic soda water are mixed evenly in sequence and added after the concentration of the mixture is measured to reach 20-22S by coating four cups.

2. The method for improving the viscosity and stability of the glue for packaging according to claim 1, wherein the preparation process comprises heating water to 15-25 ℃, adding corn starch, stirring uniformly, adding the prepared caustic soda, preparing the caustic soda with water according to the weight ratio of 3:1, stirring fully, measuring by coating four cups to reach the target concentration, adding the stabilizer and borax, and stirring uniformly; and finally, adding a bridging agent, stirring for 10min, detecting the gelatinization temperature, and taking the product out of the production line when the gelatinization temperature is 56-58 ℃.

3. The method of claim 1, wherein the corn starch is degraded before the addition of the caustic soda, specifically by adding α -amylase to the corn starch for 0.5-0.8h at 75-85 ℃, wherein the weight ratio of α -amylase to the corn starch as the substrate is 1: 100-150.

4. A method of increasing the viscosity and stability of packaging gums according to claim 3 wherein the corn starch is subjected to a preliminary gelatinization after degradation and before addition of caustic soda, in particular in hot water, i.e. the temperature is raised instantaneously to 56-58 ℃ and the gelatinization time is 2-4 min.

5. The method for improving viscosity and stability of packaging glue according to claim 1, 2, 3 or 4, wherein the amount of each raw material is controlled according to the standard of 1000-1100 kg water with 350-380 kg corn starch, 36-40 kg caustic soda, 8-10 kg bridging agent, 2-4 kg stabilizer, 6-8 kg borax.

Technical Field

The invention relates to the technical field of glue preparation, in particular to a method for improving viscosity and stability of glue for packaging.

Background

In the field of packaging, the use of glues is very frequent. In recent years, with the enhancement of environmental awareness, starch adhesives are developed and used domestically to replace traditional glues.

CN201810242034X discloses a glue for packaging paperboard production and a production process thereof, wherein the formula of the glue is as follows: corn flour, borax, sodium hydroxide, an adhesive, a stabilizer and water, wherein the water is added into a container through burdening, then the sodium hydroxide is added, the corn flour is added, the sodium hydroxide is added, the stabilizer is added, the borax is added, and the adhesive is added. The scheme can prepare the adhesive with certain permeability and stronger adhesive property. The binder was specifically added to the formulation and the best bond strength was also only 7.5N/cm from the data it provided, and reaching the aforementioned best strength was also based on the premise that glycerol, organobentonite and mastic were added to the formulation, and without the addition of glycerol, organobentonite and mastic, the bond strength was also only 6.8N/cm, which clearly increased the raw material cost and the process cost. If a simple formulation could be found, but a method could be improved in bonding strength from 6.8N/cm to 7.5N/cm and maintaining the bonding strength stable would have a significant pushing effect on the development of corn starch glue for packaging.

In addition, the existing corn adhesive has the defects of unstable quality, short storage period, easy intermolecular association during storage, poor fluidity, deep color and the like.

Disclosure of Invention

In view of the above-mentioned shortcomings of the prior art, the present invention aims to provide a method for improving the viscosity and stability of a glue for packaging.

In order to achieve the purpose, the invention adopts the technical scheme that: the method for improving the viscosity and stability of the glue for packaging is characterized in that the glue is prepared from the following raw materials of water, corn starch, caustic soda, a stabilizer, borax and a bridging agent, and the adding time of the stabilizer and the borax is controlled: the water, the corn starch and the caustic soda water are mixed evenly in sequence and added after the concentration of the mixture is measured to reach 20-22S by coating four cups.

Preferably, the preparation process comprises the steps of heating water to 15-25 ℃, adding corn starch, stirring uniformly, adding prepared caustic soda water, fully stirring, measuring by coating four cups to reach the target concentration, adding the stabilizer and borax, and stirring uniformly; and finally, adding a bridging agent, stirring for 10min, detecting the gelatinization temperature, and taking the product out of the production line when the gelatinization temperature is 56-58 ℃.

Preferably, the corn starch needs to be degraded before adding the caustic soda water, specifically, α -amylase is added into the corn starch for enzymolysis for 0.5-0.8h at 75-85 ℃, wherein the weight ratio of α -amylase to the corn starch as a substrate is 1:100-150, and the stability of the glue is improved by incomplete enzymolysis.

Preferably, the corn starch is subjected to primary gelatinization after the degradation of the corn starch and before the addition of caustic soda water, wherein the primary gelatinization is carried out in hot water, namely, the temperature is instantaneously raised to 56-58 ℃, and the gelatinization time is 2-4 min. The stability of the glue is further improved through the design of primary pasting.

Preferably, in the invention, the dosage of each raw material is controlled according to the standards of 1000-1100 kg of water matched with 350-380 kg of corn starch, 36-40 kg of caustic soda water, 8-10 kg of bridging agent, 2-4 kg of stabilizing agent and 6-8 kg of borax.

Compared with the prior art, the invention has the beneficial effects that:

1. according to the invention, the stabilizer and the borax are added at a proper time, so that the initial adhesion of the prepared glue can reach 7.5N/cm;

2. according to the invention, the corn starch is subjected to partial incomplete degradation (the addition amount and degradation time of α -amylase are controlled), and then gelatinization is carried out, so that the fluidity of the glue is effectively improved, more importantly, the glue is placed for 7 days after being prepared, the viscosity of the glue is measured to be about 7.3N/cm, and the stability of the glue is effectively improved;

the invention is suitable for paper with weight of 60-230 g.

Detailed Description

The invention will now be further elucidated with reference to specific embodiments. The following are only preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Any equivalent or similar substitutes should fall within the scope of protection of the invention without departing from the inventive concept.