Composite starch glue and preparation method thereof

Abstract

The invention belongs to the technical field of natural polymer materials, and provides a composite starch adhesive and a preparation method thereof, the starch adhesive comprises 50-100 parts of starch, 200-300 parts of water, 5-10 parts of urea resin, 200-250 parts of ethylene-vinyl acetate copolymer emulsion, 200-300 parts of a filler, 1-10 parts of an additive, 1-5 parts of an antifoaming agent, 1-10 parts of a preservative, and 5-10 parts of an initiator. The starch and the ethylene-vinyl acetate copolymer emulsion are used as main raw materials, the urea-formaldehyde resin is introduced as a cross-linking agent to prepare the starch glue, and the adhesive property can be greatly improved through copolymerization mixing of the starch and the ethylene-vinyl acetate copolymer emulsion. The addition of the filler improves the performance of the bonded starch glue, reduces the fluidity and accelerates the drying rate. The use of the additive can effectively provide hydroxyl, promote the copolymerization of starch and ethylene-vinyl acetate copolymer emulsion, and improve the performance of the starch glue.

Description

Technical Field

[0001] The present invention relates to the technical field of natural polymer materials, and particularly relates to a composite starch adhesive and a preparation method thereof. Background Art

[0002] At present, with the booming development of the packaging industry in multiple fields such as food and beverage, daily chemicals, electronics, household appliances, e-commerce and express delivery, corrugated paper packaging materials, as an indispensable part of the packaging industry, have seen a continuous rise in demand and shown a strong growth momentum. According to the latest report released by market research institution Exactitude Consultancy, the compound annual growth rate of the global corrugated box market will reach 4.43% from 2023 to 2033. It is expected that by 2033, the market size will soar from 154.75 billion US dollars in 2024 to 226.45 billion US dollars. This data undoubtedly demonstrates the importance of corrugated paper packaging in daily life and industrial production. How to keep up with the production of corrugated paper to meet this huge demand has become a difficult problem for many enterprises. And the production speed and efficiency of corrugated cardboard are inseparable from this important chemical material, the adhesive. Summary of the Invention

[0003] The purpose of the present invention is to overcome the defects in the prior art and provide a composite starch adhesive and a preparation method thereof.

[0004] In order to achieve the above invention purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a composite starch adhesive, which is prepared from raw materials comprising the following mass parts:

[0006] Starch 50 - 100 parts, water 200 - 300 parts, urea-formaldehyde resin 2 - 10 parts, ethylene-vinyl acetate copolymer emulsion 200 - 250 parts, filler 200 - 300 parts, additive 1 - 10 parts, defoamer 1 - 5 parts, preservative 1 - 10 parts, initiator 5 - 10 parts.

[0007] Preferably, the starch is one or more of corn starch, tapioca starch and glutinous rice flour.

[0008] Preferably, the filler is one or more of calcium carbonate, hydrotalcite and kaolin.

[0009] Preferably, the additive is one or more of caustic soda, polyacrylate, polyvinyl alcohol and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.

[0010] Preferably, the preservative is one or more of MBS fungicide, sorbic acid, potassium sorbate, sodium dehydroacetate, sodium benzoate and tea polyphenols;

[0011] The antifoaming agent is one or more of polydimethylsiloxane, polyoxypropylene glycerol ether, and sodium dioctyl sulfosuccinate;

[0012] The initiator is azobisisobutyronitrile and / or dimethyl azobisisobutyrate.

[0013] The present invention also provides a method for preparing the composite starch adhesive, which comprises the following steps:

[0014] (1) Mix starch, ethylene-vinyl acetate copolymer emulsion, urea-formaldehyde resin, additive, initiator, and the first portion of water for reaction to obtain an intermediate system;

[0015] (2) Mix the intermediate system, filler, antifoaming agent, and the remaining water for reaction to obtain a mixed system;

[0016] (3) Mix the mixed system and the preservative to obtain the composite starch adhesive.

[0017] Preferably, in step (1), the mass of the first portion of water is 85-90% of the total mass of water.

[0018] Preferably, in step (1), the temperature of the reaction is 80-90 °C, and the time is 30-60 min.

[0019] Preferably, in step (2), the temperature of the reaction is 80-90 °C, and the time is 2-3 h.

[0020] Preferably, in step (3), the temperature of the mixing is 35-45 °C.

[0021] The present invention provides a composite starch adhesive, which is prepared from the following raw materials in parts by mass: 50-100 parts of starch, 200-300 parts of water, 5-10 parts of urea-formaldehyde resin, 200-250 parts of ethylene-vinyl acetate copolymer emulsion, 200-300 parts of filler, 1-10 parts of additive, 1-5 parts of antifoaming agent, 1-10 parts of preservative, and 5-10 parts of initiator. The present invention uses starch and ethylene-vinyl acetate copolymer emulsion as the main raw materials, and introduces urea-formaldehyde resin as a cross-linking agent to prepare the starch adhesive. The copolymerization and mixing of starch and ethylene-vinyl acetate copolymer emulsion can greatly improve the adhesion performance. The addition of the filler improves the performance of the starch adhesive after adhesion, reduces the fluidity, and accelerates the drying rate. The use of the additive can effectively provide hydroxyl groups, promote the copolymerization of starch and ethylene-vinyl acetate copolymer emulsion, and improve the performance of the starch adhesive.

[0022] The starch adhesive provided by the present invention has great universality, can be used as an offline single-sheet mounting agent for corrugated board, and can also be applied to high-speed online mounting; it can be used for traditional low-value-added products such as cartons, and can also be applied to high-value-added fine corrugated products. Detailed implementation mode

[0023] The present invention provides a composite starch glue, which is prepared from raw materials comprising the following parts by mass:

[0024] 50-100 parts of starch, 200-300 parts of water, 2-10 parts of urea-formaldehyde resin, 200-250 parts of ethylene-vinyl acetate copolymer emulsion, 200-300 parts of filler, 1-10 parts of additive, 1-5 parts of defoaming agent, 1-10 parts of preservative, 5-10 parts of initiator.

[0025] In the present invention, the parts by mass of the starch are preferably 60-90 parts, more preferably 65-85 parts, and still more preferably 70-80 parts.

[0026] In the present invention, the parts by mass of the water are preferably 220-280 parts, more preferably 230-270 parts, and still more preferably 240-260 parts.

[0027] In the present invention, the parts by mass of the urea-formaldehyde resin are preferably 3-9 parts, more preferably 4-8 parts, and still more preferably 5-6 parts.

[0028] In the present invention, the parts by mass of the ethylene-vinyl acetate copolymer emulsion are preferably 205-245 parts, more preferably 210-240 parts, and still more preferably 220-230 parts.

[0029] In the present invention, the parts by mass of the filler are preferably 210-290 parts, more preferably 220-280 parts, and still more preferably 240-260 parts.

[0030] In the present invention, the parts by mass of the additive are preferably 2-9 parts, more preferably 3-8 parts, and still more preferably 4-7 parts.

[0031] In the present invention, the parts by mass of the defoaming agent are preferably 1.5-4.5 parts, more preferably 2-4 parts, and still more preferably 2.5-3 parts.

[0032] In the present invention, the parts by mass of the preservative are preferably 2-8 parts, more preferably 3-7 parts, and still more preferably 4-6 parts.

[0033] In the present invention, the parts by mass of the initiator are preferably 6-9 parts, more preferably 7-8 parts, and still more preferably 7.4-7.8 parts.

[0034] In the present invention, the starch is one or more of corn starch, tapioca starch and glutinous rice flour.

[0035] In the present invention, the filler is one or more of calcium carbonate, hydrotalcite and kaolin.

[0036] In the present invention, the additive is one or more of caustic soda, polyacrylate, polyvinyl alcohol, and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.

[0037] In the present invention, the preservative is one or more of MBS fungicide, sorbic acid, potassium sorbate, sodium dehydroacetate, sodium benzoate, and tea polyphenols.

[0038] In the present invention, the defoamer is one or more of polydimethylsiloxane, polyoxypropylene glycerol ether, and sodium dioctyl sulfosuccinate.

[0039] In the present invention, the initiator is azobisisobutyronitrile and / or dimethyl azobisisobutyrate.

[0040] The present invention also provides a method for preparing the composite starch adhesive, which comprises the following steps:

[0041] (1) Mix starch, ethylene-vinyl acetate copolymer emulsion, urea-formaldehyde resin, additive, initiator, and the first portion of water for reaction to obtain an intermediate system;

[0042] (2) Mix the intermediate system, filler, defoamer, and the remaining water for reaction to obtain a mixed system;

[0043] (3) Mix the mixed system and the preservative to obtain the composite starch adhesive.

[0044] In the present invention, the mass of the first portion of water in step (1) is preferably 85-90% of the total mass of water, more preferably 86-89%, and even more preferably 87-88%.

[0045] In the present invention, the temperature of the reaction in step (1) is preferably 80-90 °C, more preferably 82-88 °C, and even more preferably 84-86 °C; the time is preferably 30-60 min, more preferably 35-55 min, and even more preferably 40-50 min.

[0046] In the present invention, the temperature of the reaction in step (2) is preferably 80-90 °C, more preferably 82-88 °C, and even more preferably 84-86 °C; the time is preferably 2-3 h, more preferably 2.2-2.8 h, and even more preferably 2.4-2.6 h.

[0047] In the present invention, the temperature of the mixing in step (3) is preferably 35-45 °C, more preferably 36-44 °C, and even more preferably 38-42 °C.

[0048] The technical solution provided by the present invention will be described in detail below in conjunction with embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0049] Example 1

[0050] Weigh the following raw materials by mass: 244 kg of water, 70 kg of glutinous rice flour, 2.8 kg of urea-formaldehyde resin, 1.4 kg of caustic soda, 240 kg of ethylene-vinyl acetate copolymer emulsion, 240 kg of calcium carbonate, 3.2 kg of polydimethylsiloxane, 3.2 kg of MBS fungicide, and 6 kg of azodiisobutyronitrile.

[0051] Mix glutinous rice flour, ethylene-vinyl acetate copolymer emulsion, urea-formaldehyde resin, caustic soda, azodiisobutyronitrile and the first part of water (accounting for 88% of the total water mass), and react at 85 °C for 40 min; then add calcium carbonate, polydimethylsiloxane and the remaining water, keep the temperature at 85 °C, and continue to react for 2.5 h to obtain a mixed system; fully mix the mixed system and MBS fungicide at 40 °C to obtain the composite starch glue.

[0052] Example 2

[0053] Weigh the following raw materials by mass: 233 kg of water, 86 kg of corn starch, 7.4 kg of urea-formaldehyde resin, 3 kg of polyacrylate, 212 kg of ethylene-vinyl acetate copolymer emulsion, 265 kg of hydrotalcite, 1.6 kg of polyoxypropylene glycerol ether, 8.1 kg of sorbic acid, and 5 kg of dimethyl azodiisobutyrate.

[0054] Mix corn starch, ethylene-vinyl acetate copolymer emulsion, urea-formaldehyde resin, polyacrylate, dimethyl azodiisobutyrate and the first part of water (accounting for 85% of the total water mass), and react at 80 °C for 30 min; then add hydrotalcite, polyoxypropylene glycerol ether and the remaining water, keep the temperature at 86 °C, and continue to react for 3 h to obtain a mixed system; fully mix the mixed system and sorbic acid at 35 °C to obtain the composite starch glue.

[0055] Example 3

[0056] Weigh the following raw materials by mass: 285 kg of water, 95 kg of tapioca starch, 6 kg of urea-formaldehyde resin, 6 kg of 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, 230 kg of ethylene-vinyl acetate copolymer emulsion, 286 kg of kaolin, 4 kg of sodium dioctyl sulfosuccinate, 8 kg of tea polyphenols, and 6 kg of dimethyl azodiisobutyrate.

[0057] Mix tapioca starch, ethylene-vinyl acetate copolymer emulsion, urea-formaldehyde resin, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, dimethyl 2,2'-azobis(2-methylpropionate) and the first part of water (accounting for 90% of the total water mass), and react at 90 °C for 60 min; then add kaolin, sodium dioctyl sulfosuccinate and the remaining water, keep the temperature at 85 °C, and continue to react for 3 h to obtain a mixed system; fully mix the mixed system and tea polyphenols at 42 °C to obtain the composite starch adhesive.

[0058] Test the wet tack, slipperiness and 180° peel strength of the composite starch adhesives prepared in Examples 1 to 3 according to the JC / T 548-2016 standard, and the results are recorded in Table 1.

[0059] Table 1 Performance test results

[0060] Wet tackiness / mm Sliding property / N 180° peel strength / N / 25mm Example 1 0.38 4.1 16 Example 2 0.41 4.1 17 Example 3 0.39 4.2 14

[0061] As can be seen from the above examples, the composite starch adhesive provided by the present invention has excellent wet tack, slipperiness and 180° peel strength, indicating that the composite starch adhesive provided by the present invention has excellent water resistance, adhesive strength and stability, and can be applied to corrugated paper.

[0062] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A composite starch glue, characterized in that Prepared from the following raw materials in parts by weight: 50-100 parts of starch, 200-300 parts of water, 2-10 parts of urea-formaldehyde resin, 200-250 parts of ethylene-vinyl acetate copolymer emulsion, 200-300 parts of filler, 1-10 parts of additives, 1-5 parts of defoaming agent, 1-10 parts of preservative, and 5-10 parts of initiator.

2. The composite starch glue according to claim 1, characterized in that The starch is one or more of corn starch, tapioca starch and glutinous rice flour.

3. The composite starch glue as claimed in claim 2, characterized in that The filler is one or more of calcium carbonate, hydrotalcite and kaolin.

4. The composite starch glue as claimed in claim 3, characterized in that The additive is one or more of caustic soda, polypropylene, polyvinyl alcohol and 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.

5. The composite starch glue as claimed in claim 4, characterized in that The preservative is one or more of MBS bactericide, sorbic acid, potassium sorbate, sodium dehydroacetate, sodium benzoate and tea polyphenols; The defoaming agent is one or more of polydimethylsiloxane, polyoxypropylene glycerol ether and sodium salt of dioctyl sulfonate succinate; The initiator is azobisisobutyronitrile and / or dimethyl azobisisobutyrate.

6. The method for preparing the composite starch glue according to any one of claims 1 to 5, characterized in that: It includes the following steps: (1) mixing starch, ethylene-vinyl acetate copolymer emulsion, urea-formaldehyde resin, additives, initiator and the first part of water to react and obtain an intermediate system; (2) mixing the intermediate system, the filler, the defoamer and the remaining water to react to obtain a mixed system; (3) The mixed system and the preservative are mixed to obtain the composite starch glue.

7. The method for preparing the composite starch glue according to claim 6, characterized in that: In step (1), the mass of the first part of water is 85-90% of the mass of the total water.

8. The method for preparing the composite starch glue according to claim 7, characterized in that: The reaction temperature in step (1) is 80-90° C. and the reaction time is 30-60 min.

9. The method for preparing the composite starch glue according to claim 8, characterized in that: The reaction temperature in step (2) is 80-90° C. and the reaction time is 2-3 h.

10. The method for preparing the composite starch glue according to claim 9, characterized in that: The mixing temperature in step (3) is 35-45°C.