KR101740247B1 - Hot melt adhesive with low temperature stability - Google Patents

Abstract

The present invention provides a hot melt adhesive produced as a composition including a copolymer of starch and a first thermoplastic polymer, a second thermoplastic polymer, a plasticizer, a wax, and an adhesion imparting agent. Since a part of a thermoplastic polymer of the hot melt adhesive according to the present invention is replaced by starch which is an environmentally-friendly material, the generation amount of volatile organic compounds (VOC) is low in a production step or a usage step. Moreover, even when the hot melt adhesive according to the present invention is used for a long time, phase stability is excellent. Even when the hot melt adhesive is used at a low temperature, dissolving time is short, and operation properties are excellent. Even when being applied to a cooled or frozen product, the hot melt adhesive has excellent hardness stability, adhesive force, and heat resistance maintaining force. Moreover, the hot melt adhesive according to the present invention has quality which is similar to or more excellent than that of an industrial low temperature-type hot melt adhesive which does not contain starch.

Description

[0001] Hot melt adhesive having low temperature stability [0002]

The present invention relates to a hot-melt adhesive, and more particularly, to a hot-melt adhesive which is excellent in workability and low in volatile organic compound (VOC) generation including starch and excellent in adhesion and hardness stability A hot melt adhesive, and a method for manufacturing the same.

Adhesion refers to a state in which two surfaces are attached by the attraction force between molecules, atoms and ions. Adhesion phenomenon is widely applied in daily life to everyday life products such as tapes and bonds as well as automobiles and cutting-edge semiconductor devices Recently, the demand for adhesives for various fields has been diversified according to remarkable industrial development.

Polymer adhesives can be classified into chemical reaction type, solvent type, and hot melt type depending on the solidification process. Among them, hot-melt adhesives are easy to use and are a good example of meeting the requirements of the emerging environment.

Hot-melt adhesives (hot-melt adhesive) are solid-state materials at room temperature. They are used to make only 100% solids in heat without melting or dispersing them in a solvent. Due to DuPont's first development of ethylene-vinyl acetate resin (EVA) in the 1960s, hot-melt adhesives have advantages such as high productivity through process automation, environment-friendly characteristics, wide applicability, Showing a high growth rate. The hot melt adhesive is applied to the adherend surface in a molten state and then cooled and solidified by radiating heat on and around the adherend surface. The hot-melt adhesive does not require a drying process compared to other solvent-based adhesives and water-dispersed adhesives, and thus has a low work space and fast bonding speed. High-speed bonding enables the automation and productivity increase of the production line, which has considerable economical efficiency such as improvement of productivity, reduction of labor cost, and reduction of the amount of raw material by controlling the amount of coating. Hot melt adhesives have been applied in many fields such as packaging, bookbinding, construction, woodworking, automobiles, textiles, and electrical / electronics.

Conventional commercial hot-melt adhesives generally include ethylene-vinyl acetate nyl, polyolefin, styrene block copolymer, polyamide, polyester, and urethane (reactive hot melt) And the cohesive force is the most important among the physical properties of the resin. In the conventional commercial hot-melt adhesive, since the base resin is mainly composed of petroleum-based materials, there is a lack of environment-friendly characteristics such as a large amount of volatile organic compound (VOC) generated during the manufacturing process or use, There is a problem that the manufacturing cost may be increased due to external factors such as anxiety of supply and demand of the material and exhaustion of the petroleum-based material. In addition, conventional commercial hot melt adhesives have been problematic in workability such as occurrence of threading during use. Therefore, in consideration of environmental friendliness, stable supply of water, and cost reduction, it is necessary to replace all or a part of the base resin, which is a main component of the hot-melt adhesive, with renewable biomass, especially starch.

On the other hand, the conventional starch-based hot-melt adhesive has a problem that the compatibility between the starch and the thermoplastic polymer is insufficient, so that there is a problem that the starch-based hot-melt adhesive is melted or the precipitate is generated or separated during use, As the viscosity is changed, the viscosity change is serious, which may adversely affect the quality. In addition, since the conventional commercial hot melt adhesive is used at a high temperature of about 150 캜, it consumes a large amount of energy in the bonding operation and is limited in application to the heat-sensitive adherend. To solve this problem, research and development on a low-temperature type hot-melt adhesive have been conducted. For example, Korean Patent Registration No. 10-1089110 discloses a resin composition comprising an ethylene-2-ethylhexyl acrylate copolymer, maleic acid-modified polyethylene, a hydrogenated aliphatic hydrocarbon tackifier, and a polyethylene wax, A hot melt adhesive for packaging is disclosed. Also, Korean Patent Publication No. 10-1214557 discloses that 20 to 30% by weight of an ethylene n-butyl acrylate copolymer containing 30 to 40% by weight of n-butyl acrylate, 20 to 35% by weight 20% to 40% by weight of a Fischer-Tropsch wax having a melting point of 60 ° C to 80 ° C, and a maleic anhydride modification having a softening point of 110 ° C A hot melt adhesive containing 20 to 45% by weight of a gum rosin ester and having a low application temperature and a high heat resistance. Also, Korean Patent Registration No. 10-1507211 discloses a low-temperature applied hot-melt adhesive comprising a polyolefin copolymer component and a maleated polyethylene wax component, wherein the polyolefin copolymer component comprises two different polyolefin copolymers, Wherein the polyolefin copolymer is a metallocene-catalyzed ethylene /? - olefin copolymer made from ethylene and 1-octene monomer, the copolymer has a melt index of greater than 400 g / 10 min at 190 ° C, , Wherein the polyolefin copolymer component is present in an amount of 25 to 30 wt%, the maleated polyethylene wax component is present in an amount of 5 to 10 wt%, and the adhesive is present in an amount of 3000 centipoise Of the total weight of the low-temperature applied hot-melt adhesive. However, the ethylene-2-ethylhexyl acrylate copolymer, the ethylene n-butyl acrylate copolymer, the ethylene vinyl acetate copolymer, and the ethylene / alpha -olefin copolymer, which are used as the base resin in the conventional low temperature type hot melt adhesive, It is not environmentally friendly and is not compatible with starch, so that when it is simply mixed with starch, precipitation occurs or there is a limit to use due to a large viscosity variation depending on the use temperature. When the starch is physically mixed with a conventional low-temperature type hot-melt adhesive, the melting time is too long and workability is deteriorated. When the starch is used in a low-temperature environment such as a winter season, the hardness of the adhesive layer is too high, And the like.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and an object of the present invention is to provide a starch-containing starch which is eco-friendly containing starch, has excellent stability even when used over a long period of time, A hot melt adhesive having excellent hardness stability, adhesive strength and heat resistance even when it is applied to a product which is refrigerated or frozen, and a method for producing the same.

In order to solve the above-mentioned object, the present invention provides a hot-melt adhesive in the form of a composition comprising a copolymer of a starch and a first thermoplastic polymer, a second thermoplastic polymer, a plasticizer, a wax and a tackifier. At this time, the copolymer of the starch and the first thermoplastic polymer is obtained by grafting a copolymer of the first thermoplastic polymer to starch by ester bonding between a hydroxyl group present in the starch and a carboxyl group present in the first thermoplastic polymer, Wherein the weight ratio of the starch to the first thermoplastic polymer is from 1: 0.1 to 1: 0.42, the weight ratio of the starch to the second thermoplastic polymer is from 1: 2.4 to 1.75 and the second thermoplastic polymer is an ethylene- , Ethylene / methacrylic acid copolymer, ethylene / butyl acrylate copolymer, ethylene / ethylhexyl acrylate copolymer, and ethylene / methyl acrylate copolymer.

Since the hot-melt adhesive according to the present invention replaces a part of the thermoplastic polymer with an eco-friendly starch, the amount of volatile organic compounds (VOC) generated during the manufacturing process or use thereof is small. In addition, the hot-melt adhesive according to the present invention has excellent stability even when used for a long period of time, has excellent workability due to a short melting time even when used at a low temperature, and exhibits excellent hardness stability, (Heat Resistance). In addition, the hot melt adhesives according to the present invention have similar or better qualities to commercial low temperature hot melt adhesives that do not contain starch.

As used herein, the term "unsaturated carboxylic acid" is a generic term for organic compounds having at least one ethylenically unsaturated bond and at least one carboxyl group in the molecule.

As used herein, the term "unsaturated dicarboxylic acid" is a generic term of organic compounds having at least one ethylenic unsaturated bond and at least two carboxyl groups in the molecule, and includes an anhydride of an unsaturated dicarboxylic acid.

The present invention relates to a hot-melt adhesive having low-temperature stability, wherein a hot-melt adhesive according to an embodiment of the present invention is a composition comprising a copolymer of a starch and a first thermoplastic polymer, a second thermoplastic polymer, a plasticizer, a wax and a tackifier . Hereinafter, the hot-melt adhesive according to the present invention will be described separately for each constituent component.

Starch and first thermoplastic Of polymer  Copolymer

The copolymer of the starch and the first thermoplastic polymer used in the hot melt adhesive of the present invention is formed by grafting the starch and the first thermoplastic polymer. Specifically, the copolymer of the starch and the first thermoplastic polymer is obtained by grafting a copolymer of the first thermoplastic polymer onto starch by ester bonding between a hydroxyl group present in the starch and a carboxyl group present in the first thermoplastic polymer . The weight ratio of the starch to the first thermoplastic polymer in the copolymer of the starch and the first thermoplastic polymer is 1: 0.1 to 1: 0.42, 1: 0.2 in terms of the phase stability, melt viscosity, hardness stability, To 1: 0.4, more preferably from 1: 0.3 to 1: 0.4. The content of the copolymer of the starch and the first thermoplastic polymer in the hot melt adhesive of the present invention is preferably 5 to 10% by weight based on the total weight of the composition, considering the phase stability, melt viscosity, hardness stability, , More preferably from 6 to 9% by weight.

The starch constituting the copolymer of the starch and the first thermoplastic polymer of the present invention is not limited in its kind, and examples thereof include corn starch, waxy corn starch, tapioca starch, potato starch, sweet potato starch, rice starch, . The starch also includes non-modified starches or certain modified starches. The unmodified starch is a starch obtained from a conventional starch manufacturing process, and includes modified starches (for example, acid-treated starches, enzyme-treated starches, starch-modified starches, and starch-modified starches) whose physical properties (viscosity, thermal stability, Oxidized starch, acetyl adipic acid pre-starch, acetyl phosphate pre-starch, octenyl succinate starch, phosphate pre-phosphate, pre-phosphate phosphate, phosphoric phosphate pre-phosphate, acetic acid starch, hydroxypropyl phosphate pre-min, hydroxypropyl starch and the like. ). The starch constituting the copolymer of starch and thermoplastic polymer in the present invention is a modified starch whose degree of polymerization of starch is reduced by acid treatment or enzyme treatment in consideration of easiness of reaction and melting viscosity range for workability of hot melt adhesive desirable. Modified starches with reduced degree of polymerization of starch usually result in decreased viscosity of the liquor. Examples of such modified starches include acid-treated starches (also called acid-thinned starches or thin boiling starches), enzyme-treated starches ; Dextrin is also included in the enzyme-treated starch). The modified starch having a reduced degree of polymerization of the starch preferably has a viscosity of 20 wt% of the gelatinized solution at 50 ° C in a range of 10 to 100 centipoise (cPs), preferably 20 to 80 centipoise (cPs) Range.

Thermoplastic polymers commonly used in hot melt adhesives are composed of monomers with ethylenically unsaturated bonds, and such thermoplastic polymers are difficult to chemically bond directly with the hydroxyl groups of the starch. The inventors of the present invention introduced a first thermoplastic polymer having a carboxyl group in order to graft the thermoplastic polymer to the starch.

The first thermoplastic polymer according to one embodiment of the present invention comprises a first monomer selected from an unsaturated carboxylic acid or an anhydride thereof; A second monomer selected from olefins; And a ternary copolymer of a third monomer selected from acrylic acid, methacrylic acid, alkyl acrylate or alkyl methacrylate, which can be prepared by a known method and is commercially available. The unsaturated carboxylic acid or its anhydride, which is the first monomer, is not particularly limited as long as it has at least one ethylenic unsaturated bond and at least one carboxyl group in the molecule, and includes maleic acid, fumaric acid, At least one unsaturated dicarboxylic acid selected from the group consisting of glutaconic acid, anhydride, traumatic acid, muconic acid, citraconic acid and anhydrides thereof, When considering reactivity with starch, it is preferable to select maleic acid or its anhydride. The olefin which is the second monomer is preferably at least one selected from ethylene, propylene, butene, pentene, hexene, heptene, octene or ethylhexene, more preferably ethylene or propylene. The third monomer may be at least one monomer selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, Methacrylate, and the like. The first thermoplastic polymer according to an embodiment of the present invention has a carboxyl group by the unsaturated carboxylic acid as the first monomer. Specifically, the unsaturated carboxylic acid, which is the first monomer, forms a chemical bond with other monomers through an ethylenically unsaturated bond, and the carboxyl group existing without forming a chemical bond with other monomers is esterified with the hydroxyl group of the starch . The first thermoplastic polymer according to an exemplary embodiment of the present invention may be selected from the group consisting of maleic anhydride, a random triad of ethylene and n-butyl acrylate, and a mixture of maleic anhydride and n-butyl acrylate, in consideration of improvement in compatibility between the starch and the second thermoplastic polymer and low temperature stability of the hot- Is preferably a copolymer. The maleic anhydride, the ethylene and the n-butyl acrylate random terpolymer preferably have a butyl acrylate content of about 4 to 12 wt% and a maleic anhydride content of about 2 to 6 wt% %.

A first thermoplastic polymer according to another embodiment of the present invention is a copolymer of a first monomer selected from olefins and a second monomer selected from acrylic acid, methacrylic acid, alkyl acrylate or alkyl methacrylate, Which is modified by bonding with an anhydride, can be produced by a known method, and is commercially available. For example, an ethylene / n-butyl acrylate copolymer modified with maleic acid may be an ethylene / n-butyl acrylate copolymer (ethylene / n-butyl acrylate copolymer) (Maleic anhydride) or maleic acid (maleic acid) graft-bonded to one carboxyl group of two carboxyl groups present in the backbone of the maleic anhydride or maleic acid. A method for producing an ethylene / n-butyl acrylate copolymer in which maleic anhydride or maleic acid is graft bonded is disclosed in U.S. Patent No. 5300580 And commercially available from Arkema (France). The present invention relates to an ethylene / n-butyl acrylate copolymer having graft-bonded maleic anhydride or maleic acid as disclosed in U.S. Patent No. 5300580 See all references. The unsaturated carboxylic acid or its anhydride constituting the first thermoplastic polymer according to another example of the present invention is not limited in its kind insofar as it has at least one ethylenic unsaturated bond and at least one carboxyl group in the molecule, selected from the group consisting of acid, fumaric acid, glutaconic acid, anhydride, traumatic acid, muconic acid, citraconic acid and anhydrides thereof. And it is preferable that the unsaturated dicarboxylic acid is selected from maleic acid or an anhydride thereof in consideration of the graft-linking ability between the first monomer and the copolymer composed of the second monomer and the reactivity with the starch. The first monomer constituting the first thermoplastic polymer according to another embodiment of the present invention is preferably at least one selected from ethylene, propylene, butene, pentene, hexene, heptene, octene or ethylhexene, Is more preferable. The second monomer constituting the first thermoplastic polymer according to another embodiment of the present invention may be at least one selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, ethylhexyl acrylate, methyl methacrylate, It is preferably at least one selected from the group consisting of methyl methacrylate, ethyl methacrylate, butyl methacrylate, propyl methacrylate and ethylhexyl methacrylate. The first thermoplastic polymer according to another embodiment of the present invention has a carboxyl group by a graft-bonded unsaturated carboxylic acid of a copolymer comprising a first monomer and a second monomer. Specifically, the unsaturated carboxylic acid forms a graft bond with a copolymer composed of a first monomer and a second monomer via an ethylenically unsaturated bond, and forms a chemical bond with a copolymer composed of the first monomer and the second monomer The remaining carboxyl group forms an ester bond with the hydroxyl group of the starch. The first thermoplastic polymer according to another embodiment of the present invention may be selected from the group consisting of maleic anhydride or maleic acid in which the maleic anhydride or the maleic acid is grafted in consideration of the improvement of the compatibility between the starch and the second thermoplastic polymer and the low temperature stability of the hot- (Ethylene / n-butyl acrylate copolymer).

Second thermoplastic Polymer

The second thermoplastic polymer used in the hot-melt adhesive of the present invention is preferably an ethylene-acrylic acid copolymer, an ethylene-acrylic acid copolymer, an ethylene-acrylic acid copolymer or a methacrylic acid copolymer, in consideration of the compatibility of the above-mentioned starch with the copolymer of the first thermoplastic polymer and the low- Ethylene / butyl acrylate copolymer, an ethylene / ethylhexyl acrylate copolymer, and an ethylene / methyl acrylate copolymer. In consideration of the low-temperature stability of the hot-melt adhesive, ethylene / butyl acrylate Lt; / RTI > copolymer. The ethylene / n-butyl acrylate copolymer preferably has a butyl acrylate content of 20 to 40% by weight, more preferably 25 to 38% by weight. The ethylene / n-butyl acrylate copolymer has a melt flow index of 100 to 400 g / 10 min (190 ° C under a load of 2.16 kg, ASTM More preferably 150 to 350 g / 10 min (at 190 占 폚 under a load of 2.16 kg; test method: ASTM D1238), more preferably 150 to 400 g / method: ASTM D1238).

The weight ratio of the starch to the second thermoplastic polymer in the hot melt adhesive of the present invention is in the range of 1: 2.4 to 1: 3.75, 1: 2.5 to 1: 3.6 , More preferably from 1: 2.6 to 1: 3.5. The weight ratio of the copolymer of the starch and the first thermoplastic polymer to the second thermoplastic polymer in the hot-melt adhesive of the present invention is preferably 1: 1.5 to 1: 2.6 in consideration of the phase stability, melt viscosity, hardness stability, , More preferably from 1: 1.8 to 1: 2.5. The content of the second thermoplastic polymer in the hot melt adhesive of the present invention is preferably 160 to 260 parts by weight based on 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer.

Plasticizer

In the hot-melt adhesive of the present invention, the plasticizer is used for imparting flexibility and adhesion to the polar polymer, and the type thereof is not particularly limited. For example, the plasticizer may be selected from conventional surfactants, urea, and the like. When considering the plasticizing ability of starch when preparing the copolymer of starch and the first thermoplastic polymer, sorbitol, ethylene glycol, glycerin, glycerin diacetate glycerin diacetate and pentaerythritol, and more preferably at least one selected from the group consisting of sorbitol and ethylene glycol. In the hot-melt adhesive of the present invention, the content of the plasticizer is not particularly limited, but is preferably 90 to 110 parts by weight relative to 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer in consideration of harmony with other components, More preferably by weight.

Wax

In the hot-melt adhesive of the present invention, the wax has a function of improving the fluidity of the hot-melt adhesive or increasing the thermal stability, and the type thereof is not limited to a great extent. For example, the wax may be at least one selected from the group consisting of paraffin wax, microcrystalline wax, polyethylene wax, polypropylene wax, amide wax and Fischer-Tropsch wax, In consideration of the phase stability of the hot melt adhesive, the melt viscosity, the hardness stability, and the low temperature adhesive force, it is preferable that the hot melt adhesive is at least one selected from the group consisting of paraffin wax, polyethylene wax and Fischer-Tropsch wax.

The Fischer-Tropsch wax may also be classified as paraffin wax. Commercially available products of paraffin waxes that can be used in the present invention include Okerin 236 TP, available from Astor Wax Corporation (Doraville, GA); Penreco 4913, available from Pennzoil Products Co. (Houston, Tex.); R-7152 paraffin wax sold by Moore & Munger (Shelton, Conn.); Paraffin wax 1297 available from International Waxes, Ltd. (Ontario, Canada); Pacemaker marketed by Citgo; And R-2540 available from Moore and Munger; And other paraffin waxes such as 1230, 1236, 1240, 1245, 1246, 1255, 1260, and 1262, paraffin waxes available from CP Hall. The microcrystalline wax comprises at least 50% by weight of a cyclic alkane or a branched alkane containing a chain having from 30 to 100 carbon atoms. In general, microcrystalline wax has a lower crystallinity than paraffin wax and polyethylene wax, and has a melting point higher than about 70 캜. Commercial products of microcrystalline waxes that can be used in the present invention include Victory Amber Wax, available from Petrolite Corp. of Tulsa, Okla., USA, having a melting point of 70 占 폚; Bareco ES-796, available from Bareco (Chicago, Ill., USA), having a melting point of 70 캜; Okerin 177 sold by Astor Wax Corp. with a melting point of 80 ° C; Besquare 175 and 195 Amber Waxes available from Petrolite Corp. (Tulsa, Oklahoma) having melting points of 80 ° C and 90 ° C, respectively; Indramic 91 having a melting point of 90 ° C and commercially available from Industrial Raw Materials (Smesport, Pa.); But are not limited to, Petrowax 9508 Light sold by Petrowax PA, Inc. of New York, NY, with a melting point of 90 ° C. Commercial products of polyethylene waxes that may be used in the present invention include, but are not limited to, Polywax 500, Polywax 1500, and Polywax 2000 available from Petrolite, Inc. of Tulsa, Okla. In addition, the amide wax which can be used in the present invention may be selected from the compounds represented by the following general formula (1).

[Chemical Formula 1]

Wherein R ₁ is an alkanediyl group having 2 to 4 carbon atoms, R ₂ is a hydrocarbon group having 15 to 20 carbon atoms or a hydroxy hydrocarbon group having 15 to 20 carbon atoms, R ₃ and / R < ₄ > are independent of each other and represent a hydrocarbon group having 1 to 3 carbon atoms or hydrogen)

In the present invention, the hydrocarbon group is a functional group composed of carbon and hydrogen, and includes an alkyl group, an alkenyl group, and an aryl group. The compound represented by Formula 1 may be obtained by reacting a fatty acid or a hydroxy fatty acid such as oleic acid, linoleic acid, arachidonic acid, palmitic acid, stearic acid, Two amide bonds are formed by the reaction of diamines such as ethylenediamine, 1,4-diaminobutane and 1,3-diaminopropane. And generally has a high melting point of about 135 캜 to 165 캜. In the general formula (1), R ₂ is a hydrocarbon group such as an alkyl group, an alkenyl group or an aryl group, or a hydroxy hydrocarbon group thereof, preferably an alkyl group or a hydroxyalkyl group. In the formula (1), R ₃ and R ₄ are preferably hydrogen or a methyl group. Specific examples of the compound represented by the formula (1) include 1,2-ethylenebis (stearamide); CAS Registry No. 110-30-5], 1,2-Ethylenebis (hydroxystearamide); 1,2-Ethylenebis (hydroxystearamide); CAS Registry No. 38162-95-7 or 123-26-2] and 1,3-propylenebis (palmitamide) [1,3-Propylenebis (palmitamide); CAS Registration No. 54535-68-1], N-N'-ethane-1,2-diylbis (N-ethylstearamide) ; CAS registration number 262-923-7].

Further, the Fischer-Tropsch wax is a synthetic wax produced by the Fischer-Tropsch method, which is commercially available as Sasolwax (R) product (for example, Sasolwax (R) H1) , Paraflint® products, or Polywax® products from Baker Petolite (eg Polywax® C80).

In the hot-melt adhesive of the present invention, the content of the wax is not particularly limited, but is preferably 280 to 400 parts by weight, more preferably 300 to 380 parts by weight per 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer, More preferably by weight.

Tackifier

In the starch-based hot-melt adhesive according to the present invention, the tackifier is a low-molecular-weight resin and when used in combination with a copolymer of a starch and a first thermoplastic polymer as basic components, the melt viscosity is lowered to improve workability, In some cases, a functional group may be imparted to improve the initial wetting property of the adhesive and the adhesion of the starch-based hot-melt adhesive to the surface of the adherend, and to control the solidification time. In the starch-based hot-melt adhesive according to the present invention, the tackiness-imparting agent is not limited in its kind such as a rosin-based resin, a terpene resin, a coumarone-indene resin and a petroleum resin, and the phase stability, melt viscosity, hardness stability, It is preferable that the resin is selected from a rosin-based resin or a petroleum resin, and more preferably at least one selected from the group consisting of a rosin ester, a hydrogenated hydrocarbon resin and an aromatic-modified hydrocarbon resin.

Examples of the rosin-based resin include gum rosin, wood rosin, tall oil rosin, distilled rosin, hydrogenated rosin, dimerized rosin, ), Resinate, and polymerized rosin; and the like; Natural rosins and modified rosins, including pale rosin, glycerol ester of wood rosin, glycerol ester of hydrogenated rosin, glycerol ester of polymerized rosin, pentaerythritol ester of hydrogenated rosin, phenol-modified pentaerythritol ester of rosin Of glycerol esters and pentaerythritol esters. Commercial products of rosin-based resins include Komotac KF382S, Komotac KF392S, Komotac KF452S, Komotac KF462S, Komotac KS-2090, Komotac KS-2100, Komotac KS-2110, Komotac KZ223S and Komotac KZ224S of Komo Chemical. . In the present invention, the rosin ester is obtained by reacting rosin acid with an alcohol such as methanol, triethylene glycol or pentaerythritol to convert the rosin acid into an ester, and includes esters of natural rosin and esters of modified rosin Concept. Commercially available rosin esters include Pinerez 2130, Pinerez 2220, Pinerez 2240, Pinerez 2330, Pinerez 2385 from Akzo Nobel-Eka chemicals; Ester Gum 105 from Arakawa Chemical, Ester Gum 106, Ester Gum A, Ester Gum AAL, Ester Gum AAV; Aquatac E 5375, Aquatac E 6180, Sylvalite RE 10L, Sylvalite RE 80 HP, Sylvalite RE 85L from Arizona Chemical; Pentalyn 710-M, Permalyn 2085, TACOLYN 3100, and TACOLYN 3179 H from Eastman Chemical Company. In the present invention, when the rosin ester is used as the tackifier, the melt viscosity of the hot melt adhesive and the adhesion time indicated by the set time can be maintained at an optimum level, so that the workability can be improved. Among the tackifier resins used in the present invention, terpene resins include natural terpene copolymers and terpolymers including styrene / terpene and alpha methylstyrene / terpene; A polyterpene resin having a softening point measured according to ASTM method E28-58T of about 70 deg. C to about 150 deg. A phenol-modified terpene resin containing a resin product produced by condensation reaction of bicyclic terpene and phenol in an acidic medium, and hydrogenated derivatives thereof. As the petroleum resin among the tackifiers used in the present invention, an aliphatic hydrocarbon resin, a cycloaliphatic hydrocarbon resin, an aromatic hydrocarbon resin, an aromatic-modified aliphatic hydrocarbon Resins, aromatic modified aliphatic hydrocarbon resins, and hydrogenated hydrocarbon resins. Commercial products of aliphatic hydrocarbon resins include Hikorez A-1100, Hikorez A-1100S, Hikorez C-1100, Hikorez R-1100, and Hikorez R-1100S from Kolon Oil Company (Korea). The alicyclic hydrocarbon resin includes a hydrocarbon resin containing dicyclopentadiene (DCPD) as a monomer, and disclosed in Korean Patent Publication No. 1998-013719 and Korean Patent Publication No. 2008-0093733. Commercial products of aromatic hydrocarbon resins include Hikotack P-110S, Hikotack P-120, Hikotack P-120HS, Hikotack P-120S, Hikotack P-140, Hikotack P- 140M, Hikotack P-150, Hikotack P-160, Hikotack P-90, Hikotack P-90S, Hirenol PL-1000 and Hirenol PL-400. Commercial products of aromatic modified aliphatic hydrocarbon resins include Hikorez T-1080 and Hikorez T-1100 from Kolon Chemical Industries, Ltd. (Korea). Hydrogenated hydrocarbon resins may be further classified into hydrogensified aliphatic hydrocarbon resins, hydrogeneated aromatic hydrocarbon resins, etc. Commercially available products include Sukorez D-300, Sukorez D-390 , Sukorez SU-100, Sukorez SU-110, Sukorez SU-120, Sukorez SU-130, Sukorez SU-90, Hikorez H-2100, Hikorez H-2130, Hikorez H-2200 and Hikorez H-2300. In addition, the tackifier used in the present invention may include a hydrocarbon resin having 4 to 10 carbon atoms in the monomer, and more specifically, a C5 aliphatic resin, a C9 aromatic resin, and a C5 / C9 aliphatic / aromatic copolymer resin. In addition, the tackifier used in the present invention may include a hydrogendic hydrocarbon resin containing dicyclopentadiene (DCPD) as a monomer, and may be a commercial product such as Sukorez D-300, Sukorez D-390, Sukorez SU-100, Sukorez SU-110, Sukorez SU-120, Sukorez SU-130 and Sukorez SU-90.

In the hot-melt adhesive of the present invention, the content of the tackifier is not particularly limited, but is preferably 360 to 560 parts by weight based on 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer, More preferably 550 parts by weight.

Other ingredients

The hot melt adhesive according to the present invention may further comprise an auxiliary additive in addition to the copolymer of the starch and the first thermoplastic polymer, the second thermoplastic polymer, the plasticizer, the wax and the tackifier. The auxiliary additives change the physical properties of the hot melt adhesive or impart specific functions to the hot melt adhesive. The auxiliary additives which can be used in the hot-melt adhesive according to the present invention may be at least one selected from the group consisting of polybutene, oil, filler and antioxidant. Polybutene is added for improvement of water resistance or imparting flexibility. The oil is added for imparting flexibility, improving the process such as melt kneading, and the like. Filler is a substance that is added to the purpose of anti-aging, reinforcement, and increase in the practical use of rubber or plastic, and is used to control the flowability of the hot-melt adhesive. The type of filler is not critical and may be selected from, for example, one or more of calcium carbonate, clay, bentonite, or calcium stearate. The antioxidant may be added when a material containing a structure that can be easily oxidized due to its low thermal stability is used to improve the viscosity change due to oxidation and decomposition, yellowing, lowering of adhesion and lowering of durability. The kind of the antioxidant is not particularly limited, and examples thereof include phenols, aromatic amines, citric acid, and ascorbic acid. The content of the auxiliary additive in the hot-melt adhesive according to the present invention is preferably 0.1 to 6 parts by weight, more preferably 1 to 5 parts by weight, based on 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer.

The method of manufacturing a hot melt adhesive according to the present invention comprises the steps of: (a) plasticizing starch in the presence of a plasticizer to form a plasticized starch slurry; (b) adding a wax, a first thermoplastic polymer and a second thermoplastic polymer to the plasticized starch slurry and melt-mixing them to form a first composition; (c) adding a radical reaction initiator to the first composition and reacting to form a second composition comprising a copolymer of starch and the first thermoplastic polymer; And (d) adding a tackifier to the second composition and melt mixing to form a third composition. In the method for producing a hot-melt adhesive according to the present invention, the types and blending ratios of the starch, the first thermoplastic polymer, the second thermoplastic polymer, the plasticizer, the wax, and the tackifier are the same as those described above, and thus a detailed description thereof will be omitted.

In the step (a) of the method for producing a hot-melt adhesive of the present invention, the starch is heated at a predetermined temperature range and plasticized by the plasticizer. The temperature range for plasticizing starch in step (a) is preferably 80 to 120 ° C, more preferably 90 to 110 ° C.

In the step (b) of the method for producing a hot-melt adhesive of the present invention, the wax, the first thermoplastic polymer and the second thermoplastic polymer are heated at a predetermined temperature range and melt-mixed with the plasticized starch slurry. In the step (b), the melt mixing temperature is preferably 90 to 150 ° C, more preferably 100 to 140 ° C.

In the step (c) of the method for producing a hot-melt adhesive of the present invention, a radical reaction initiator is used to induce an ester bond reaction between a hydroxyl group present in the starch and a carboxyl group present in the first thermoplastic polymer. The radical reaction initiator may be an organic peroxide, an azo compound (for example, 2,2-azobisbutyronitrile, 2,2'-azobis-2-methylbutyronitrile, etc.), sodium persulfate, But is not limited to the type commonly used for radical reactions such as potassium persulfate and the like, and organic peroxide is preferably used in consideration of the reactivity between the starch and the first thermoplastic polymer. The organic peroxide may be selected from the group consisting of benzoyl peroxide, acetyl peroxide, dilauryl peroxide, di-tert-butyl peroxide, cumyl But are not limited to, cumyl hydroperoxide, di-t-butyl hydroperoxide, dibenzoyl peroxide, succinic peroxide, dilauryl peroxide, Dicumyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane [2,5-dimethyl-2,5- di- (t-butylperoxy) hexane], [alpha] -cumyl peroxy-neodecanoate, 1,1-dimethyl-3-hydroxybutylperoxy-2-ethylhexanoate 1-dimethyl-3-hydroxybutyl peroxy-2-ethyl hexanoate, t-amyl peroxy-benzoate, Selected from t-butyl peroxy-pivalate, 2,5-dihydroperoxy-2,5-dimethylhexane, cumene hydroperoxide and the like. But may not be limited thereto. The reaction temperature in step (c) is preferably 110 to 160 ° C, more preferably 120 to 150 ° C, but is not limited thereto.

In the step (d) of the method for producing a hot-melt adhesive of the present invention, the tackifier is heated and melted and mixed with the second composition at a predetermined temperature range. The melting and mixing temperature in step (d) is preferably 120 to 150 ° C.

Since the hot-melt adhesive according to the present invention replaces a part of the thermoplastic polymer with an eco-friendly starch, the amount of volatile organic compounds (VOC) generated during the manufacturing process or use thereof is small. In addition, the hot-melt adhesive according to the present invention exhibits a melt viscosity which is easy to apply at a low temperature, and the melting time is short and workability is excellent. The hot-melt adhesive according to the present invention is excellent in stability even when used for a long period of time and has high quality reliability. In addition, the hot-melt adhesive according to the present invention is excellent in hardness stability, adhesive strength, and heat resistance even when it is applied to a product to be refrigerated or frozen. The use of the hot-melt adhesive having such properties is not limited in its application and can be applied to many fields such as packaging, bookbinding, construction, woodworking, automobiles, textile, electric / electronic, Can be used as an adhesive.

Hereinafter, the present invention will be described more specifically with reference to Examples. However, the following examples are intended to clearly illustrate the technical features of the present invention, and do not limit the scope of protection of the present invention.

One. Starch-based Hot melt  Manufacture of adhesives

Production Example 1

3.12 parts by weight of ethylene glycol, 6.41 parts by weight of D-sorbitol as a plasticizer, and 0.26 parts by weight of a 50% by weight solution of hypophosphoric acid as a viscosity modifier were mixed, and then the mixture was placed in a reactor maintained at a temperature of 100 ± 5 ° C And the plasticizer was melted by stirring for about 10 minutes. Thereafter, 6.80 parts by weight of acid-treated corn starch (viscosity at 50 ° C: 30 to 50 cPs of a 4 wt% enriched solution: 30-50 cPs; manufactured by Toho Kagaku Co., Ltd.) was added to the reactor while maintaining the temperature of the reactor at 100 ° C ± 5 ° C And the mixture was stirred for about 40 minutes to prepare a plasticized starch slurry. Thereafter, 15.63 parts by weight of polyethylene wax was added to the reactor while maintaining the temperature of the reactor at 100 ° C ± 5 ° C, and the mixture was stirred for about 30 minutes to melt the wax. Then, 5.24 parts by weight of the functional resin was added as a compatibilizing agent to the reactor while maintaining the temperature of the reactor at 100 ° C ± 5 ° C, the temperature of the reactor was raised to 130 ° C ± 5 ° C, Followed by melt mixing. The functional resin is a random terpolymer having a maleic anhydride, ethylene and n-butyl acrylate as monomers and has a butyl acrylate content of about 6.0 wt% And the maleic anhydride content is about 3.1% by weight. The random terpolymer of maleic anhydride, ethylene and n-butyl acrylate is commercially available from Arkema (France) , &Quot; MA / EnBA " in the following description. Thereafter, the reactor had a butyl acrylate content of about 35 wt% and a melt flow index of about 320 g / 10 min (190 캜, 2.16 kg load 13.58 parts by weight of an ethylene / n-butyl acrylate copolymer (hereinafter referred to as "EnBA") as a test method (ASTM D1238) was added and melt-mixed with other components for 30 minutes A first composition was obtained. Thereafter, the temperature of the reactor was raised to 145 ± 5 ° C, and a radical reaction initiator, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane [2,5- 0.14 part by weight of di (tert-butylperoxy) hexane was added thereto, and the mixture was reacted for about 90 minutes to prepare a starch-thermoplastic polymer graft copolymer having a graft-bonded form of MA / EnBA via a carboxyl group present in maleic anhydride Lt; RTI ID = 0.0 > 2 < / RTI > Thereafter, while maintaining the temperature of the reactor at 145 占 占 폚, 39.95 parts by weight of a hydrogenated hydrocarbon resin (trade name: Eastotac (TM) H-100W) as a tackifier and 40.95 parts by weight of tetrakis 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxymethyl] methane (Tetrakis [3- Methane) were added and melted and mixed for about 30 minutes to 1 hour to prepare a starch-based hot-melt adhesive.

Production Examples 2 to 15.

In Production Examples 2 to 15, starch-based hot-melt adhesives were prepared by changing the kinds and contents of the ingredients while maintaining the same process conditions as used in Production Example 1. Tables 1 to 3 show the types and contents of the components used in Production Examples 1 to 15. The ingredients in the following Tables 1 to 3 are based on 100 parts by weight of the finally obtained starch-based hot-melt adhesive.

division Production Example 1 Production Example 2 Production Example 3 Production Example 4 Production Example 5 Compounding ingredient Starch 6.80 6.23 6.23 6.23 6.00 Plasticizer 1 3.12 2.86 2.86 2.86 - Plasticizer 2 6.41 5.87 5.87 5.87 8.45 Acid 0.26 0.24 0.24 0.24 0.20 MA / Enba 5.24 4.80 4.80 2.40 2.00 EnBA 1 13.58 12.43 14.64 17.04 18.00 EnBA 2 - - - - - EnBA 3 - - - - - Wax 1 15.63 14.31 20.00 - - Wax 2 8.64 7.90 10.00 - - Wax 3 - - - 30.00 30.00 Initiator 0.14 0.13 0.13 0.13 0.12 Tackifier 1 39.95 45.00 35.00 35.00 35.00 Tackifier 2 - - - - - Antioxidant 0.23 0.23 0.23 0.23 0.23

division Production Example 6 Production Example 7 Production Example 8 Production Example 9 Production Example 10 Compounding ingredient Starch 6.23 5.75 5.54 6.00 6.00 Plasticizer 1 2.86 - - - - Plasticizer 2 5.87 8.05 7.80 8.45 8.45 Acid 0.24 0.22 0.18 0.20 0.20 MA- g -EnBA 2.40 2.22 1.85 2.00 2.20 EnBA 1 17.04 15.73 16.61 18.00 19.80 EnBA 2 - - - - - EnBA 3 - - - - - Wax 1 20.00 27.69 27.68 25.00 23.00 Wax 2 10.00 - - - - Wax 3 - - - - - Initiator 0.13 0.12 0.11 0.12 0.12 Tackifier 1 35.00 40.00 - - - Tackifier 2 - - 40.00 40.00 40.00 Antioxidant 0.23 0.23 0.23 0.23 0.23

division Production Example 11 Production Example 12 Production Example 13 Production Example 14 Production Example 15 Compounding ingredient Starch 5.54 5.54 5.54 5.54 6.00 Plasticizer 1 - - - - - Plasticizer 2 7.80 7.80 7.80 7.80 8.45 Acid 0.18 0.18 0.18 0.18 0.20 MA- g -EnBA 2.50 2.80 1.85 1.85 2.00 EnBA 1 21.61 23.61 - - - EnBA 2 - - 16.61 - 18.00 EnBA 3 - - - 16.61 - Wax 1 22.03 19.73 - - - Wax 2 - - - - - Wax 3 - - 27.68 27.68 25.00 Initiator 0.11 0.11 0.11 0.11 0.12 Tackifier 1 - - - - - Tackifier 2 40.00 40.00 40.00 40.00 40.00 Antioxidant 0.23 0.23 0.23 0.23 0.23

The blending components used in Tables 1 to 3 are as follows.

* Starch: Acid-treated corn starch (Viscosity at 50 ° C of 4% by weight of gelatin solution: 30 to 50 cPs;

* Plasticizer 1: Ethylene glycol

* Plasticizer 2: D-sorbitol

Acid: 50% by weight solution of hypophosphoric acid

* MA / EnBA: Maleic anhydride, a random terpolymer of ethylene and n-butyl acrylate having a butyl acrylate content of about 6.0 wt% and a maleic anhydride content of about 3.1 wt% LOTADER® 3210, manufacturer: Arkema, France)

* EnBA 1: an ethylene / n-butyl acrylate copolymer having a butyl acrylate content of about 35% by weight and a melt flow index of about 320 g / 10 min Test method: ASTM D1238) (LOTRYL® 35BA320, manufactured by Arkema, France)

* EnBA 2: an ethylene / n-butyl acrylate copolymer having a butyl acrylate content of about 28% by weight and a melt flow index of about 175 g / 10 min ( Test method: ASTM D1238) (trade name: LOTRYL® 28BA175; manufactured by Arkema, France)

EnBA 3: ethylene / n-butyl acrylate copolymer having a butyl acrylate content of about 35% by weight and a melt flow index of about 40 g / 10 min. Test method: ASTM D1238) (trade name: LOTRYL® 35BA40, manufactured by Arkema, France)

* Wax 1: polyethylene wax

* Wax 2: Fischer-Tropsch wax (product name: Sasolwax H1; manufactured by Sasol wax, South Africa)

* Wax 3: Paraffin wax

* Initiator: 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane [

* Tackifier 1: Hydrogenated hydrocarbon resin (product name: Eastotac ™ H-100W)

Tackifier 2: hydrocarbon resin of C5 monomer modified with C9 aromatic hydrocarbons (product name: Wingtack® ET; manufactured by Cray Valley)

* Antioxidant: Tetrakis [3- (3,5-Di-t-butyl-4-hydroxyphenyl) propionyloxymethyl] Hydroxyphenyl) Propionyl-Oxymethyl] Methane)

Comparative Production Example 1

8.45 parts by weight of D-sorbitol as a plasticizer and 0.20 parts by weight of a 50% by weight solution of hypophosphoric acid as a viscosity modifier were mixed, and the mixture was placed in a reactor maintained at a temperature of 100 ± 5 ° C, And the plasticizer was melted by stirring. Thereafter, 6.00 parts by weight of acid-treated corn starch (viscosity at 50 ° C: 30 to 50 cPs of a 4 wt% enrichment liquid: 30-50 cPs; manufactured by Toho Kagaku Co., Ltd.) was added to the reactor while maintaining the temperature of the reactor at 100 ° C ± 5 ° C And the mixture was stirred for about 40 minutes to prepare a plasticized starch slurry. Then, 25.00 parts by weight of polyethylene wax was added to the reactor while maintaining the temperature of the reactor at 100 占 폚 占 5 占 폚, and the mixture was stirred for about 30 minutes to melt the wax. Thereafter, the temperature of the reactor was raised to 130 ° C ± 5 ° C, and then the reactor had a butyl acrylate content of about 35% by weight and a melt flow index of about 320 g / 10 min (190 ° C, 2.16 kg load 20.00 parts by weight of an ethylene / n-butyl acrylate copolymer (hereinafter abbreviated as "EnBA"), which is a thermoplastic resin (ASTM D1238, Test Method: ASTM D1238), was melted and mixed with the other components for 30 minutes . Thereafter, the temperature of the reactor was raised to 145 +/- 5 DEG C, and 40.12 parts by weight of a hydrocarbon resin of C5 monomer (trade name: Wingtack® ET; manufactured by Cray Valley) modified with a C9 aromatic hydrocarbon as a tackifier for the tackifier and 40.12 parts by weight of tetrakis (3,5-Di-tert-butyl-4-hydroxyphenyl) propionyloxymethyl] methane ] Methane) were added and melt-mixed for about 30 minutes to 1 hour to prepare a starch-based hot-melt adhesive.

Comparative Preparation Example 2

3.25 parts by weight of ethylene glycol and 6.55 parts by weight of D-sorbitol were added to the reactor, and the temperature of the reactor was raised to 100 DEG C to melt the plasticizer. Then, while maintaining the temperature of the reactor at 100 ° C., 0.43 part by weight of maleic anhydride, which is a reactive monomer, and 0.26 parts by weight of a 50% by weight solution of a hypophosphoric acid as a viscosity regulator were added to the reactor, Respectively. Thereafter, 6.49 parts by weight of acid-treated corn starch (viscosity at 50 ° C: 30 to 50 cPs of a 4 wt% enrichment liquid: 30 to 50 cPs; manufactured by Toho Kagaku Co., Ltd.) was added to the reactor while the temperature of the reactor was maintained at 100 ° C, And reacted for 50 minutes to obtain a first composition containing a modified starch wherein the hydroxyl value of the starch was replaced with maleic acid. Thereafter, the reactor was charged with a thermoplastic polymer having a vinyl acetate content of about 28 wt% and a melt flow index of about 400 g / 10 min (190 캜, 2.16 kg load; Test method: ASTM D1238) 15.27 parts by weight of a copolymer (Ehtylene Vinyl Acetate Copolymer, EVA), 12.46 parts by weight of polyethylene wax as wax and 5.22 parts by weight of Fischer-Tropsch wax (trade name: Sasolwax H1; manufactured by Sasol wax, South Africa) And mixed with the first composition. Thereafter, the temperature of the reactor was raised to 130 캜, and a radical reaction initiator, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane [2,5- 0.06 part by weight of tert-butylperoxy) hexane was added thereto and the mixture was reacted for about 90 minutes to obtain a starch-thermoplastic polymer graft having an ethylene-vinyl acetate copolymer graft-copolymerized with maleic acid (or maleic anhydride) A second composition comprising a copolymer was obtained. Thereafter, 22.29 parts by weight of rosin ester (product name: Pinerez 2130; supplier: Akzo Nobel-Eka chemicals), 22.29 parts by weight of hydrogenated hydrocarbon resin (trade name: Eastotac ™ H-100W) And 5.21 parts by weight of a hydrocarbon resin of a C5 monomer modified with a C9 aromatic hydrocarbon (trade name: Wingtack® ET; manufactured by Cray Valley) were added and mixed, and then tetrakis [3- (3,5- 0.23 part by weight of t-butyl-4-hydroxyphenyl) propionyloxymethyl] methane (Tetrakis [3- (3,5- Di- Tert-Butyl-4-hydroxyphenyl) propionyloxymethyl] A starch-based hot-melt adhesive in the form of a composition was prepared.

2. Hot melt  How to measure the physical properties of adhesives

In order to evaluate the workability and adhesive force of the starch-based hot-melt adhesive prepared in Production Examples 1 to 15, Comparative Production Examples 1 and 2, the following property measurement tests were carried out. In addition, a property measurement test was also conducted on non-electric hot melt adhesive (product name: COOL 501; manufactured by Henkel), which is commercially available as a control.

(1) Phase stability

Whether or not precipitates were formed in the finally obtained hot-melt-type hot-melt adhesive or the starch-based hot-melt adhesive was stored at 130 ° C for 24 hours, and then the occurrence of gel-type precipitates was observed. When a gel type precipitate was generated, it was evaluated as 'poor', and when gel type precipitate did not occur, it was evaluated as 'good'. For the starch-based hot-melt adhesive evaluated as defective, no further physical property test was conducted.

(2) Melt viscosity

The melt viscosity of the hot melt adhesive was measured using a viscometer (model name: HBDV-11 + P) equipped with a Thermosel system (a constant temperature device) manufactured by Brookfield. Specifically, 13 ml of a hot melt adhesive of pellet type was placed in a sample chamber, melted completely at about 130 캜, and the melt viscosity was measured using a SC4-28 spindle. The melt viscosity was measured by varying the melting temperature.

(3) Softening point

The softening point was measured by the ring and ball method specified in KS M 2250.

(4) Hardness

The hardness (Shore A type) was measured by the method specified in ASTM D2240. The hardness was measured on the uniform surface by keeping the sample at the temperature (20 ° C, 50 ° C) for a certain period of time.

(5) Heat resistance

Heat retention was measured by the method specified in ASTM D3654. The retention force was sampled by unifying the carton box, and the retention time was counted with the same weight (200 g) applied to each sample after setting the temperature of the retention force tester in the laboratory.

(6) Open time

Open time was measured by the method specified in ASTM D4497. A certain amount of the hot melt adhesive melted at the use temperature was applied to the A4 paper and the time was counted, and the corrugated paper cut in the same size was adhered (constant pressure) according to elapsed time (seconds). After the hot melt adhesive was sufficiently cooled, the bonded corrugated board was bonded and broken in order, and the open time was determined according to the destruction mode of the corrugated board. The last time the deposited material was destroyed was defined as open time.

(7) Melt speed

The melting rate was measured using a mobile hot melt applicator provided in the laboratory. The same amount of hot melt adhesive was placed in a 130 캜 applicator and then the time was counted, and the time when the liquid reached the complete liquid phase was regarded as the melting rate.

(8) Low temperature adhesion

The A4 paper was adhered at room temperature using a hot melt adhesive and stored for 24 hours under normal freezing conditions. At this time, not only the failure mode but also the breakage of the hot-melt adhesive were checked at the same time, and the low-temperature adhesive force was evaluated qualitatively as "good", "normal", and "bad".

3. Hot melt  Measurement results of adhesive properties

Table 4 shows the results of measuring the phase stability, the melt viscosity, the hardness and the low temperature adhesion of the starch-based hot-melt adhesive obtained in Production Examples 1 to 15 and Comparative Examples 1 and 2 and the commercial non-conductive hot melt adhesive COOL 501 to be.

Hot-melt adhesive Phase stability Melt viscosity (cPs, @ 130 ° C) Hardness (20 캜 / 50 캜) Low temperature adhesion
(A4 small package) Operating temperature (℃) Production Example 1 Bad - - - - Production Example 2 Bad - - - - Production Example 3 Bad - - - - Production Example 4 Good Unmeasured Unmeasured Unmeasured 130 Production Example 5 Good Unmeasured Unmeasured Unmeasured 130 Production Example 6 Good Unmeasured Unmeasured Unmeasured 130 Production Example 7 Good 720 60/32 Good 130 Production Example 8 Good 720 54/15 Good 130 Production Example 9 Good 960 67/38 Good 130 Production Example 10 Good 1200 62/30 Good 130 Production Example 11 Good 1760 64/30 Bad 130 Production Example 12 Good 2640 61/30 Bad 130 Production Example 13 Good 800 62/31 Good 130 Production Example 14 Good 1280 68/39 Good 130 Production Example 15 Good 1040 76/40 Good 130 Comparative Preparation Example 1 Poor (phase separation and deposit formation during manufacturing process) - - - - Comparative Production Example 2 Good 1440 87/67 usually 130 COOL 501 Good 1520 58/35 Good 130

When the ethylene / n-butyl acrylate copolymer was mechanically mixed with the plasticized starch (Comparative Preparation Example 2) as shown in the above Table 4, phase separation and gel-type starch precipitates were produced during the production process. In addition, when the content of graft-bound MA / EnBA in the starch was relatively high and the content of EnBA physically mixed with the starch was relatively low (Production Example 1, Production Example 2 and Production Example 3) Gelatinous starch precipitates were formed when stored. In addition, when the content of EnBA physically mixed with starch was too high (Production Example 11 and Production Example 12), the melt viscosity was too high, resulting in poor workability and poor low temperature adhesion.

Table 5 shows all the physical properties of the starch-based hot-melt adhesive prepared in Production Example 9 of the present invention, the starch-based hot-melt adhesive prepared in Comparative Production Example 2, and the commercial non-conductive hot melt adhesive COOL 501.

division Production Example 9 Comparative Production Example 2 COOL 501 (Henkel) The melt viscosity (cPs) @ 130 ℃ 960 1440 1520 @ 140 ℃ 800 720 1120 @ 150 ℃ 640 480 720 Softening point (℃) 93 112 114 Hardness (20 캜 / 50 캜) 67/38 87/67 58/35 Heat Retention (@ 50 ℃) 22-92 minutes Unmeasured 1 to 57 minutes Open Time 20 seconds 15 seconds 15 seconds Melt rate (@ 130 ℃) 4 minutes 50 seconds 7 minutes 4 minutes 40 seconds Low temperature adhesion (A4 small package) Good usually Good Phase stability Good Good Good Operating temperature (℃) 130 130 130

As shown in Table 5, the starch-based hot-melt adhesive prepared in Production Example 9 of the present invention exhibited excellent adhesion, retention and hardness at low temperatures, improved melting performance and workability, and a viscosity The change is not large, and the reliability of the quality can be obtained. As a result, the starch-based hot-melt adhesive of the present invention showed equivalent or superior physical properties to commercial non-conductive low-temperature hot-melt adhesives in a low temperature environment.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Therefore, the scope of protection of the present invention should not be limited to the specific embodiments disclosed as the best mode, but should be construed as including all embodiments belonging to the claims attached hereto.

Claims (15)

A composition of a composition comprising a copolymer of a starch and a first thermoplastic polymer, a second thermoplastic polymer, a plasticizer, a wax and a tackifier,
The copolymer of the starch and the first thermoplastic polymer is obtained by grafting a copolymer of the first thermoplastic polymer to starch by ester bonding between a hydroxyl group present in the starch and a carboxyl group present in the first thermoplastic polymer,
Wherein the weight ratio of the starch to the first thermoplastic polymer is from 1: 0.1 to 1: 0.42,
Wherein the second thermoplastic polymer is selected from the group consisting of an ethylene-acrylic acid copolymer, an ethylene / methacrylic acid copolymer, an ethylene / butyl acrylate copolymer, an ethylene / ethylhexyl acrylate copolymer and an ethylene / methyl acrylate copolymer One or more,
The content of the copolymer of the starch and the first thermoplastic polymer is 5 to 10% by weight based on the total weight of the composition,
The content of the second thermoplastic polymer is 160 to 260 parts by weight based on 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer,
The content of the plasticizer is 90 to 110 parts by weight based on 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer,
The content of the wax is 280-400 parts by weight based on 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer,
Wherein the content of the tackifier is 360 to 560 parts by weight based on 100 parts by weight of the copolymer of the starch and the first thermoplastic polymer.
The hot-melt adhesive according to claim 1, wherein the starch is a modified starch having reduced degree of polymerization of starch by acid treatment or enzymatic treatment.
The method of claim 1, wherein the first thermoplastic polymer comprises a first monomer selected from an unsaturated carboxylic acid or an anhydride thereof; A second monomer selected from olefins; And a tertiary copolymer of a third monomer selected from acrylic acid, methacrylic acid, alkyl acrylate or alkyl methacrylate.
The method of claim 3, wherein the first monomer is selected from the group consisting of maleic acid, fumaric acid, glutaconic acid, anhydride, traumatic acid, muconic acid, Wherein the unsaturated dicarboxylic acid is at least one unsaturated dicarboxylic acid selected from the group consisting of citraconic acid and anhydrides thereof.
The hot-melt adhesive according to claim 3, wherein the second monomer is at least one selected from the group consisting of ethylene, propylene, butene, pentene, hexene, heptene, octene and ethylhexene.
4. The composition of claim 3, wherein the third monomer is selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, Methyl methacrylate, propyl methacrylate, propyl methacrylate, propyl methacrylate, propyl methacrylate, propyl methacrylate, butyl methacrylate, and ethylhexyl methacrylate.
The method of claim 1, wherein the first thermoplastic polymer comprises a copolymer of a first monomer selected from olefins and a second monomer selected from acrylic acid, methacrylic acid, alkyl acrylate or alkyl methacrylate, Wherein the hot-melt adhesive is modified by bonding with an anhydride.
The method of claim 7, wherein the unsaturated carboxylic acid is selected from the group consisting of maleic acid, fumaric acid, glutaconic acid, anhydride, traumatic acid, muconic acid, Wherein the unsaturated dicarboxylic acid is at least one unsaturated dicarboxylic acid selected from the group consisting of citraconic acid and anhydrides thereof.
The hot-melt adhesive according to claim 7, wherein the first monomer is at least one selected from the group consisting of ethylene, propylene, butene, pentene, hexene, heptene, octene and ethylhexene.
The composition of claim 7, wherein the second monomer is selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, Methyl methacrylate, propyl methacrylate, propyl methacrylate, propyl methacrylate, propyl methacrylate, propyl methacrylate, butyl methacrylate, and ethylhexyl methacrylate.
The hot-melt adhesive according to claim 1, wherein the weight ratio of the copolymer of the starch and the first thermoplastic polymer to the second thermoplastic polymer is from 1: 1.5 to 1: 2.6.
The hot-melt adhesive according to claim 1, wherein the plasticizer is at least one selected from the group consisting of sorbitol, ethylene glycol, glycerin, glycerin diacetate and pentaerythritol.
The wax according to claim 1, wherein the wax is at least one selected from the group consisting of paraffin wax, microcrystalline wax, polyethylene wax, polypropylene wax, amide wax and Fischer-Tropsch wax Wherein the hot melt adhesive is a hot melt adhesive.
The tackifier of claim 1, wherein the tackifier is selected from the group consisting of rosin ester, an aliphatic hydrocarbon resin, a cycloaliphatic hydrocarbon resin, an aromatic hydrocarbon resin, an aromatic modified aliphatic hydrocarbon resin An aromatic modified aliphatic hydrocarbon resin, and a hydrogenated hydrocarbon resin.
The hotmelt adhesive of claim 1, wherein the weight ratio of the starch to the second thermoplastic polymer is from 1: 2.4 to 1: 3.75.