CN115477905B - Polyolefin hot melt adhesive with rapid surface drying and preparation method thereof - Google Patents

Abstract

The application provides a quick-surface-drying polyolefin hot melt adhesive which comprises the following raw materials in parts by weight: 30-60 parts of polyolefin; 5-20 parts of crystallization auxiliary agent; 20-50 parts of tackifying resin; 1-15 parts of viscosity modifier; 0.1-1 part of antioxidant. The application also provides a preparation method of the polyolefin hot melt adhesive with quick surface drying. A crystallization aid is added into the raw materials of the polyolefin hot melt adhesive to accelerate the surface drying speed; meanwhile, a large amount of low-viscosity wax is avoided, and the influence on the mechanical strength and flexibility of the hot melt adhesive is avoided.

Description

Polyolefin hot melt adhesive with rapid surface drying and preparation method thereof

Technical Field

The application relates to the technical field of glue, in particular to a polyolefin hot melt adhesive with a quick surface drying function and a preparation method thereof.

Background

A hot melt adhesive is a thermoplastic polymer that does not require solvents, 100% solids. The hot melt adhesive melts and rapidly solidifies during cooling, resulting in excellent mechanical strength. Compared with other adhesives, the hot melt adhesive has the advantages of no solvent, convenient synthesis, short curing time, wide bonding range, convenient storage and transportation and no environmental pollution, accords with the dominant direction of green chemistry, and belongs to an environment-friendly chemical product. Because the product is solid, the packaging, the transportation, the storage, the solvent and the pollution are convenient, and the product is nontoxic; the method has the advantages of simple production process, high added value, high adhesive strength, high speed and the like, and is favored. With the development of petrochemical industry, various thermoplastic materials such as ethylene-vinyl acetate copolymer (EVA), polyamide (PA), polyolefin, etc. are used as a base material of hot melt adhesives, and have been widely used in the fields of wood, shoemaking, clothing, automobiles, packaging, etc.

The quick operation is a great characteristic of the hot melt adhesive. The operation time of the hot melt adhesive is generally about 15 seconds, and along with the wide application of modern production lines, the operation time requirement on the hot melt adhesive is shorter and shorter, for example, the operation time requirement on the hot melt adhesive for packaging and sticking tubes, book binding and loudspeaker box manufacturing reaches about 5 seconds. There is a need for a hot melt adhesive that wets the substrate quickly and sufficiently while possessing a fast cure rate to provide a certain bond strength. Generally, the use of low viscosity waxes, such as Fischer-Tropsch, polyolefin, paraffin, microcrystalline waxes, etc., in hot melt adhesive formulations can significantly accelerate the cure rate, but have some effect on the adhesive properties of the hot melt adhesive material and are less flexible.

Disclosure of Invention

In order to achieve the above object, the present application is achieved by the following technical solutions.

The application provides a quick-surface-drying polyolefin hot melt adhesive which comprises the following raw materials in parts by weight:

preferably, the polyolefin is selected from at least one of polyethylene, polypropylene, polybutylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, amorphous polyalphaolefin.

Preferably, the crystallization aid comprises the following raw materials in parts by weight:

4.9-18 parts of high-crystallinity polyolefin;

0.1-2 parts of nucleating agent.

Preferably, the high crystalline polyolefin is at least one selected from the group consisting of linear low density polyethylene, high density polyethylene, isotactic polypropylene, and isotactic polybutylene.

Preferably, the nucleating agent is at least one selected from sorbitol derivatives, organic carboxylic acids, organic carboxylic acid metal salts, organic phosphates, talc, calcium carbonate, mica.

Preferably, the tackifying resin is selected from at least one of rosin, rosin derivatives, terpene resins, petroleum resins, thermoplastic phenolic resins, low molecular weight polystyrene.

Preferably, the viscosity modifier is selected from at least one of naphthenic mineral oil, hydrogenated polybutadiene, paraffin wax, microcrystalline wax, fischer-Tropsch wax, polyethylene wax, oxidized polyethylene wax, polypropylene wax, sand rope wax.

Preferably, the antioxidant is at least one selected from the group consisting of antioxidant B215, antioxidant 1010, antioxidant 168, antioxidant 1076 and antioxidant 3114.

A second object of the present application is to provide a process for preparing a polyolefin hot melt adhesive having a rapid tack free as described above comprising the steps of:

s1, heating the inside of a reaction container to a temperature exceeding 100 ℃;

s2, adding polyolefin, a crystallization aid, tackifying resin, a viscosity modifier and an antioxidant into the reaction container according to the measurement, vacuumizing, and stirring to react to obtain the polyolefin hot melt adhesive.

Preferably, the reaction temperature is 180℃to 220 ℃.

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

the application provides a quick surface drying polyolefin hot melt adhesive, which is prepared by adding a crystallization aid into raw materials of the polyolefin hot melt adhesive so as to accelerate the surface drying speed; meanwhile, a large amount of low-viscosity wax is avoided, and the high-viscosity wax has high mechanical strength and flexibility.

The foregoing description is only an overview of the present application, and is intended to provide a better understanding of the technical means of the present application, and is to be implemented in accordance with the contents of the specification, as follows, in accordance with the preferred embodiments of the present application, as hereinafter described in detail with reference to the accompanying drawings. Specific embodiments of the present application are given in detail by the following examples and the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute a limitation on the application. In the drawings:

FIG. 1 is a flow chart of the steps of the preparation method of the present application.

Detailed Description

The foregoing and other objects, features, aspects and advantages of the present application will become more apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a device for practicing the application. In the drawings, the shape and size may be exaggerated for clarity, and the same reference numerals will be used throughout the drawings to designate the same or similar components. In the following description, terms such as center, thickness, height, length, front, back, rear, left, right, top, bottom, upper, lower, etc. are based on the orientation or positional relationship shown in the drawings. In particular, "height" corresponds to the top-to-bottom dimension, "width" corresponds to the left-to-right dimension, and "depth" corresponds to the front-to-back dimension. These relative terms are for convenience of description and are not generally intended to require a particular orientation. Terms (e.g., "connected" and "attached") referring to an attachment, coupling, etc., refer to a relationship wherein these structures are directly or indirectly secured or attached to one another through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise.

The present application will be further described with reference to the accompanying drawings and detailed description, wherein it is to be understood that, on the premise of no conflict, the following embodiments or technical features may be arbitrarily combined to form new embodiments.

The application provides a quick-surface-drying polyolefin hot melt adhesive which comprises the following raw materials in parts by weight:

in the embodiment, a crystallization aid is added into the raw materials of the polyolefin hot melt adhesive to accelerate the surface drying speed; meanwhile, the scheme of accelerating the curing rate by adding low-viscosity wax in the traditional hot melt adhesive formula is replaced, so that a large amount of low-viscosity wax is avoided, and the influence on the mechanical strength and flexibility of the hot melt adhesive is avoided. Namely, by adopting the technical scheme of adding the crystallization auxiliary agent, the surface drying speed of the hot melt adhesive can be increased, and meanwhile, the hot melt adhesive can have higher mechanical strength and flexibility.

In one embodiment, the polyolefin is selected from at least one of Polyethylene (PE), polypropylene (PP), polybutylene (PB), ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), amorphous Polyalphaolefin (APAO). Specifically, polyolefin is used as a matrix resin to form a polyolefin hot melt adhesive system having a necessary adhesive strength and cohesive force.

In one embodiment, the crystallization aid comprises the following raw materials in parts by weight:

4.9-18 parts of high-crystallinity polyolefin;

0.1-2 parts of nucleating agent.

Further, the high crystalline polyolefin is at least one selected from the group consisting of Linear Low Density Polyethylene (LLDPE), high Density Polyethylene (HDPE), isotactic polypropylene (iPP), and Isotactic Polybutylene (iPB). Specifically, the high-crystallinity polyolefin has higher molecular chain regularity, compact arrangement, higher crystallinity, stronger crystallization capability after melting and cooling, faster crystallization rate and shorter surface drying time. The high crystalline polyolefin is preferably isotactic polypropylene (iPP) _。

Further, the nucleating agent is at least one selected from sorbitol derivatives, organic carboxylic acids, organic carboxylic acid metal salts, organic phosphates, talcum powder, calcium carbonate and mica. Specifically, the addition of the nucleating agent can obviously improve the crystallization peak temperature of the high-crystallinity polyolefin, quicken the crystallization rate and shorten the crystallization time, thereby shortening the surface drying time. The nucleating agent is preferably a sorbitol derivative.

Further, the highly crystalline polyolefin is preferably 8 to 12 parts, and the nucleating agent is preferably 0.2 to 0.8 parts.

In one embodiment, the tackifying resin is selected from at least one of rosin, rosin derivatives, terpene resins, petroleum resins, thermoplastic phenolic resins, low molecular weight polystyrene. Specifically, the tackifying resin can have excellent compatibility with the polyolefin host resin described above, and can improve wettability and initial adhesion. Further, terpene resins include modified terpene resins. Further, the petroleum resin includes hydrogenated petroleum resin.

In one embodiment, the viscosity modifier is selected from at least one of naphthenic mineral oil, hydrogenated polybutadiene, paraffin wax, microcrystalline wax, fischer-Tropsch wax, polyethylene wax, oxidized polyethylene wax, polypropylene wax, sand rope wax. Specifically, the viscosity regulator is used for reducing the viscosity of the prepared polyolefin hot melt adhesive, reducing the softening point and further improving the low temperature resistance of the polyolefin hot melt adhesive.

In one embodiment, the antioxidant is selected from at least one of antioxidant B215, antioxidant 1010, antioxidant 168, antioxidant 1076, antioxidant 3114. Specifically, the antioxidant is used for improving the thermal stability of the polyolefin hot melt adhesive, preventing the physical properties of the polyolefin hot melt adhesive from aging, and reducing the color change of the polyolefin hot melt adhesive.

The application also provides a preparation method of the polyolefin hot melt adhesive with the rapid surface drying function, which is shown in figure 1 and comprises the following steps:

s1, heating the inside of a reaction container to a temperature exceeding 100 ℃;

s2, adding polyolefin, a crystallization aid, tackifying resin, a viscosity modifier and an antioxidant into the reaction container according to the measurement, vacuumizing, and stirring to react to obtain the polyolefin hot melt adhesive.

The preparation method is simple and has mild process conditions.

Further, the reaction temperature is greater than 130 ℃. Preferably, the reaction temperature is 180℃to 220 ℃. The reaction temperature may be heated in place in step S1 or in place in step S2.

Further, step S2 further includes the steps of: after the reaction is completed, clear liquid is obtained, and the polyolefin hot melt adhesive is obtained after filtration.

The process of the present application is illustrated by the following specific examples, it being understood that these examples are illustrative of the basic principles, main features and advantages of the present application, and the present application is not limited by the scope of the following examples; the implementation conditions employed in the examples may be further adjusted according to specific requirements, and the implementation conditions not specified are generally those in routine experiments.

In the examples and comparative examples below, the polyolefin was designated as Affinity GA1900, available from Dow Corp. The tackifying resin was available under the trade designation Wingtack 98 from Cray Valley; the viscosity modifier is available from Honeywell under the trade designation A-C1660. Antioxidants were available from Tianjin An Long under the designations 1010 and 168; the weight ratio of antioxidant 1010 to antioxidant 168 is 1:1.

Example 1

The preparation of the polyolefin hot melt adhesive with quick surface drying comprises the following steps:

(1) Heating to 120 ℃ in a reaction kettle;

(2) Adding 50 parts by weight of polyolefin, 4.9 parts by weight of high-crystallinity polyolefin, 0.1 part by weight of nucleating agent, 40 parts by weight of tackifying resin, 10 parts by weight of viscosity modifier and 0.5 part by weight of antioxidant into a reaction kettle, vacuumizing to-0.9 MPa, stirring, reacting at 180 ℃ for 4 hours, reacting completely to form clear liquid, and filtering to obtain polyolefin hot melt adhesive;

wherein, the liquid crystal display device comprises a liquid crystal display device,

the high crystalline polyolefin is linear low density polyethylene, with the trade mark of M500026, and is purchased from Sabic company;

the nucleating agent is talcum powder, the brand is SG-2000, and the nucleating agent is purchased from Nippon Talc company.

Example 2

The preparation of the polyolefin hot melt adhesive with quick surface drying comprises the following steps:

(1) Heating to 130 ℃ in a reaction kettle;

(2) Adding 40 parts by weight of polyolefin, 15 parts by weight of high-crystallinity polyolefin, 1 part by weight of nucleating agent, 40 parts by weight of tackifying resin, 10 parts by weight of viscosity modifier and 0.5 part by weight of antioxidant into a reaction kettle, vacuumizing to-0.9 MPa, stirring, reacting at 190 ℃ for 4 hours, completely forming clear liquid, and filtering to obtain polyolefin hot melt adhesive;

wherein the high crystalline polyolefin is high density polyethylene, and the brand is Alathon H4250, which is purchased from Lyondell Basell company;

the nucleating agent is an organic phosphate, with the trade name of NA-21, which is purchased from Adeka company.

Example 3

The preparation of the polyolefin hot melt adhesive with quick surface drying comprises the following steps:

(1) Heating to 140 ℃ in a reaction kettle;

(2) Adding 45 parts by weight of polyolefin, 10 parts by weight of high-crystallinity polyolefin, 0.5 part by weight of nucleating agent, 40 parts by weight of tackifying resin, 10 parts by weight of viscosity modifier and 0.5 part by weight of antioxidant into a reaction kettle, vacuumizing to-0.9 MPa, stirring, reacting at 200 ℃ for 4 hours, completely forming clear liquid, and filtering to obtain polyolefin hot melt adhesive;

wherein the high crystalline polyolefin is isotactic polypropylene with the brand of PP7945E1, and is purchased from Exxon Mobil company;

the nucleating agent is a sorbitol derivative, and is available from Milliken company under the trade name Millad 3940.

Example 4

The preparation of the polyolefin hot melt adhesive with quick surface drying comprises the following steps:

(1) Heating to 150 ℃ in a reaction kettle;

(2) Adding 35 parts by weight of polyolefin, 18 parts by weight of high-crystallinity polyolefin, 2 parts by weight of nucleating agent, 40 parts by weight of tackifying resin, 10 parts by weight of viscosity modifier and 0.5 part by weight of antioxidant into a reaction kettle, vacuumizing to-0.9 MPa, stirring, reacting at 210 ℃ for 4 hours, completely forming clear liquid, and filtering to obtain polyolefin hot melt adhesive;

wherein the high crystalline polyolefin is isotactic polybutene, with the brand of Koattro PB M1500M, available from Lyondell Basell;

the nucleating agent is an organic carboxylate, and the brand is SG-2000, which is purchased from Nippon Talc company.

Comparative example 1

The preparation method of the hot melt adhesive comprises the following steps:

(1) Heating to 120 ℃ in a reaction kettle;

(2) 45 parts by weight of polyolefin, 10 parts by weight of polyethylene wax (brand name: epolene N-14, purchased from Westlake company), 40 parts by weight of tackifying resin, 10 parts by weight of viscosity modifier and 0.5 part by weight of antioxidant are added into a reaction kettle, the mixture is vacuumized to-0.9 MPa, stirred, the reaction temperature is 180 ℃, the reaction is carried out for 4 hours, clear liquid is completely formed, and the mixture is filtered to obtain the hot melt adhesive.

Comparative example 2

The preparation method of the hot melt adhesive comprises the following steps:

(1) Heating to 120 ℃ in a reaction kettle;

(2) 50 parts by weight of polyolefin, 40 parts by weight of tackifying resin, 10 parts by weight of viscosity modifier and 0.5 part by weight of antioxidant are added into a reaction kettle, the mixture is vacuumized to-0.9 MPa, stirred, and reacted at 180 ℃ for 4 hours, and clear liquid is completely formed after the reaction, and filtered, so that the hot melt adhesive is obtained.

The hot melt adhesives prepared in examples 1 to 4 and comparative examples 1 and 2 were subjected to performance test.

The softening point test method is carried out according to GB/T15332.

Melt viscosity was measured according to HG/T3660-1999.

180℃peel strength was measured according to GB/T2790.

The method for testing the surface dry time comprises the following steps: 8g of the hot melt adhesive was placed in an aluminum foil cup, melted for 30 minutes at 165℃and taken out after confirming complete melting, and the surface was lightly touched with the tip of a toothpick at 23℃and was regarded as tack free.

The light transmittance test method is according to GB/T1038-2000.

Tensile strength and elongation at break test methods were as per GB/T528-2009.

The test results are shown in Table I.

List one

As can be seen from table one, the high crystalline polyolefin and the nucleating agent were added in examples 1 to 4, the polyethylene wax was used for comparative example 1 to adjust the tack-free time of the hot melt adhesive, and the crystallization aid and the polyethylene wax were not used for comparative example 2. The results show that, while examples 1 to 4 can achieve the same level of tack-free time as comparative example 1, the tensile strength and light transmittance thereof are significantly improved relative to comparative example 1. The above shows that the addition of the crystallization aid to the polyolefin hot melt collagen material can enhance the tensile strength and improve the light transmittance.

In the crystallization process of examples 1 to 4, the spherulites were reduced in size and the number of crystal nuclei and crystallites was increased, thereby improving the crystallinity and the tensile strength of the hot melt adhesive. The surface drying time, tensile strength and light transmittance of the example 3 are obviously better than those of the examples 1 to 3, the sorbitol derivative has a similar crystalline structure with isotactic polypropylene, the system compatibility is good, the dispersion is easy, and the effect is more efficient.

In addition, the content of the highly crystalline polyolefin and the nucleating agent should be in a suitable range, i.e., the content of the crystallization aid should be in a suitable range. Excessive crystallization aid content can reduce the high-temperature wettability of the glue, thereby reducing the peel strength; the crystallization aid content is too low, so that the crystallization rate of the whole material is not easy to accelerate, and the surface drying time is not easy to shorten.

The above is only a preferred embodiment of the present application, and is not intended to limit the present application in any way; those skilled in the art can smoothly practice the application as shown in the drawings and described above; however, those skilled in the art will appreciate that many modifications, adaptations, and variations of the present application are possible in light of the above teachings without departing from the scope of the application; meanwhile, any equivalent changes, modifications and evolution of the above embodiments according to the essential technology of the present application still fall within the scope of the present application.

Claims (6)

1. The quick-surface-drying polyolefin hot melt adhesive is characterized by comprising the following raw materials in parts by weight:

30-60 parts of polyolefin;

5-20 parts of crystallization auxiliary agent;

20-50 parts of tackifying resin;

1-15 parts of viscosity modifier;

0.1-1 part of antioxidant;

the polyolefin is selected from at least one of polyethylene, polypropylene, polybutene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer and amorphous poly alpha olefin;

the crystallization aid comprises the following raw materials in parts by weight:

4.9-18 parts of high-crystallinity polyolefin;

0.1-2 parts of nucleating agent;

the high-crystallinity polyolefin is at least one selected from linear low-density polyethylene, high-density polyethylene, isotactic polypropylene and isotactic polybutylene;

the nucleating agent is at least one selected from sorbitol derivatives, organic carboxylic acid metal salts, organic phosphates, talcum powder, calcium carbonate and mica.

2. The quick surface drying polyolefin hot melt adhesive of claim 1, wherein the tackifying resin is selected from at least one of rosin, rosin derivatives, terpene resins, petroleum resins, thermoplastic phenolic resins, low molecular weight polystyrene.

3. The quick surface drying polyolefin hot melt adhesive of claim 1, wherein the viscosity modifier is selected from at least one of a naphthenic mineral oil, hydrogenated polybutadiene, paraffin wax, microcrystalline wax, fischer-tropsch wax, polyethylene wax, oxidized polyethylene wax, polypropylene wax, sand rope wax.

4. The quick surface drying polyolefin hot melt adhesive of claim 1, wherein the antioxidant is selected from at least one of antioxidant B215, antioxidant 1010, antioxidant 168, antioxidant 1076, antioxidant 3114.

5. The method for preparing a polyolefin hot melt adhesive with rapid surface drying as claimed in claim 1, comprising the steps of:

s1, heating the inside of a reaction container to a temperature exceeding 100 ℃;

s2, adding polyolefin, a crystallization aid, tackifying resin, a viscosity modifier and an antioxidant into the reaction container according to the measurement, vacuumizing, and stirring to react to obtain the polyolefin hot melt adhesive.

6. The process of claim 5, wherein the reaction temperature is 180 ℃ to 220 ℃.