JPH0518876B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a polyamide that has excellent adhesive performance from low to high temperatures, weather resistant adhesive performance, and water resistant adhesive performance, and particularly excellent heat cycle resistance, weather resistant durability, and water resistant durability at high temperatures. The present invention relates to a polyamide-based hot-melt adhesive composition, particularly a polyamide-based hot-melt adhesive composition that exhibits excellent adhesion performance to metals. In recent years, the demand for adhesives, especially hot-melt adhesives for metals, has been rapidly increasing in fields such as aircraft, automobiles, construction machinery, and machine assembly.However, the performance of hot-melt adhesives used in these technical fields is In addition to excellent adhesive performance such as tensile shear strength and T-peel strength under a wide range of temperature conditions from low to high temperatures, it also has excellent adhesive performance such as water resistance, heat resistance, weather resistance, and durability. High reliability is required in performance such as excellent heat cycle durability, excellent adhesion speed, and excellent workability. Conventionally, many types of adhesives have been known in terms of their composition. In particular, adhesives for metals include acrylic adhesives, cyanoacrylic adhesives, epoxy adhesives, aliphatic polyamide adhesives such as nylon, aliphatic polyamide/epoxy adhesives, vinyl/phenolic adhesives, Nitrile/phenolic adhesives, polyimide adhesives, etc. have traditionally been used. Among these metal adhesives, acrylic adhesives, cyanoacyl adhesives, epoxy adhesives, aliphatic polyamide adhesives such as nylon, and aliphatic polyamide/epoxy adhesives have excellent adhesive performance at high temperatures and It has poor water-resistant adhesive performance and can only be used at temperatures below 100°C. Furthermore, although the adhesive performance of vinyl phenolic adhesives, nitrile phenolic adhesives, and polyimide adhesives has been considerably improved at high temperatures, it is still far from being sufficient, and they are inferior in terms of water-resistant adhesive performance. It's on. None of the adhesives satisfies the performance required of metal adhesives used in the above-mentioned technical fields, and they are only used for limited applications in limited fields. Furthermore, it has been proposed in various prior art documents that polyamides composed of aromatic dicarboxylic acid component units and fatty acid diamine component units can be used as hot melt adhesives. For example, Japanese Patent Publication No. 45-6825, Japanese Patent Publication No. 54-3767, Japanese Patent Application Laid-Open No. 51-41738, Japanese Patent Application Publication No. 1342-1982, and U.S. Patent No. 3790423, etc.
It is described that polyamides comprising various aromatic dicarboxylic acid component units and various fatty acid diamine component units and having various compositions can be used as hot melt adhesives. However, no matter which polyamide described in these prior art documents is used as a hot-melt adhesive, especially a hot-melt adhesive for metal, the adhesive performance at high temperatures, heat resistance durability, weather resistance durability, and heat resistance are insufficient. Poor cycle durability and water resistance,
It does not fully satisfy the adhesive performance required for metal adhesives. As a result of searching for a high-performance adhesive composition for metals, the present inventors found that an adhesive containing a polyamide consisting of an aromatic dicarboxylic acid component unit and a specific diamine component unit was found to be a hot-melt adhesive that satisfies the above objectives. The present invention was achieved based on the discovery that the present invention can be used as a drug composition. The hot melt adhesive composition of the present invention has tensile shear strength, T-peel strength, heat resistance durability, heat cycle resistance, weather resistance durability, water resistance durability, under a wide range of temperature conditions from low to high temperatures. It is characterized by excellent adhesive construction workability, and in particular, it can significantly lower adhesive construction workability, especially the adhesive construction temperature, without significantly reducing heat resistance durability, heat cycle resistance durability, and water resistance durability. It has the characteristic of being able to That is, the present invention provides 60 terephthalic acid component units.
in the range from 100 mol% and isophthalic acid, 2
- Aromatic dicarboxylic acid component unit (a) consisting of 0 to 40 mol% of aromatic dicarboxylic acid component units selected from methyl terephthalic acid and naphthalene dicarboxylic acid and 30 aliphatic alkylene diamine component units having 6 to 12 carbon atoms A hot-melt type polyamide containing a polyamide composed of diamine component units (b) in the range of 95 to 95 mol% and 70 to 5 mol% of alicyclic diamine or aromatic diamine component units having 6 to 20 carbon atoms. It is an adhesive composition. The polyamide used as an adhesive component in the hot melt adhesive composition of the present invention has a polyamide content of 60 to 100%.
Range of mol% and aromatic dicarboxylic acid component units selected from isophthalic acid, 2-methylterephthalic acid, naphthalene dicarboxylic acid 0 to 40 mol%
Aromatic dicarboxylic acid component unit (a) consisting of the range of
and 30 to 95 mol% of aliphatic alkylene diamine component units having 6 to 12 carbon atoms and 6 carbon atoms.
The polyamide is composed of diamine component units (b) comprising 70 to 5 mol % of alicyclic diamine or aromatic diamine component units. The intrinsic viscosity [η] of the polyamide measured in concentrated sulfuric acid at 30° C. is usually in the range of 0.3 to 2.5 dl/g, preferably 0.5 to 2.0 dl/g, particularly preferably 0.6 to 1.8 dl/g. The aromatic dicarboxylic acid component units other than the terephthalic acid component units constituting the polyamide for the hot melt adhesive composition of the present invention include isophthalic acid, 2-methylterephthalic acid, and naphthalene dicarboxylic acid component units. The composition of the aromatic dicarboxylic acid component unit (a) may be a single terephthalic acid component unit, but it may be a mixture of a terephthalic acid component unit and the above-mentioned aromatic dicarboxylic acid component units other than the terephthalic acid component unit. It's okay. In either case, the aromatic dicarboxylic acid component units (a) constituting the polyamide range from 60 to 100 mol% of terephthalic acid component units and from 0 to 40 mol% of aromatic dicarboxylic acid component units other than terephthalic acid component units.
It is necessary that the amount be within the range of mol%. Furthermore, the composition of the aromatic dicarboxylic acid component unit (a) is 60 to 85 mol% of the terephthalic acid component unit when the aliphatic alkylene diamine component unit constituting the polyamide is an aliphatic alkylene diamine having 6 carbon atoms.
and aromatic dicarboxylic acid component units selected from isophthalic acid, 2-methylterephthalic acid, and naphthalene dicarboxylic acid are in the range of 15 to 40 mol %, adhesiveness under high temperature conditions ranging from low to high temperatures is achieved. This is particularly preferred since performance, heat resistance durability and water resistance durability are improved. In addition, when the aliphatic alkylene diamine component unit (b) constituting the polyamide is an aliphatic alkylene diamine having 8 carbon atoms, 65 to 65 terephthalic acid component units
If it is in the range of 100 mol% and in the range of 0 to 35 mol% of aromatic dicarboxylic acid component units other than terephthalic acid component units, adhesive performance, heat resistance durability, and water resistance under a wide range of temperature conditions from low to high temperatures will be improved. This is particularly preferred since durability is improved. In addition, when the aliphatic alkylene diamine component unit constituting the polyamide is an aliphatic alkylene diamine having 10 to 12 carbon atoms, the terephthalic acid component unit is in the range of 75 to 100 mol% and isophthalic acid,
When the aromatic dicarboxylic acid component unit selected from 2-methylterephthalic acid is in the range of 0 to 25 mol%, adhesive performance, heat resistance durability, and water resistance durability under a wide range of temperature conditions from low to high temperatures are improved. This is particularly preferable. The composition of the aromatic dicarboxylic acid component unit (a) is such that the terephthalic acid component unit is less than 60 mol% and the aromatic dicarboxylic acid component unit other than the terephthalic acid component unit is 40%.
When the amount exceeds mol%, the adhesive performance at high temperatures, heat resistance durability, and water resistance durability of the hot melt adhesive will decrease. The aromatic dicarboxylic acid component unit (a) constituting the polyamide is mainly composed of the terephthalic acid component unit and the aromatic dicarboxylic acid component unit other than the terephthalic acid component unit. In addition, it may contain a small amount of tribasic or higher polyhydric carboxylic acid component units such as trimellitic acid and pyromellitic acid. The diamine component unit (b) constituting the polyamide for the hot melt adhesive composition of the present invention has 6 carbon atoms.
to 12 aliphatic alkylene diamine component units in the range of 30 to 95 mol% and alicyclic diamine or aromatic diamine component units having 6 to 20 carbon atoms
It is necessary that the diamine component unit is comprised in the range of 70 to 5 mol%. The diamine component unit
When the content of the aliphatic alkylene diamine component units constituting (b) is greater than 95 mol% and the content of the alicyclic diamine or aromatic diamine component units is less than 5 mol%, the hot melt type The bonding temperature of the adhesive becomes high and the workability decreases, and the content of the aliphatic alkylene diamine component unit becomes less than 30 mol%, and the content of the aliphatic alkylene diamine component unit becomes less than 70 mol%. If it becomes larger, the tensile shear strength from low to high temperatures, boiling water resistance, etc. of the hot melt adhesive will decrease. When the diamine component unit (b) constituting the polyamide for hot-melt adhesives of the present invention is composed of an aliphatic alkylene diamine component unit and an alicyclic diamine component unit, the preferred composition ratio of both diamines is The aliphatic alkylene diamine component unit is in the range of 35 to 85 mol% and the alicyclic diamine component unit is in the range of 35 to 85 mol%.
Preferably, it is in the range of 65 to 15 mol%.
When the diamine component unit (b) constituting the polyamide is composed of an aliphatic alkylene diamine component unit and an aromatic diamine component unit, the preferred composition ratio of both diamines is the aliphatic alkylene diamine component. The unit is in the range of 60 to 95 mol% and the aromatic diamine component unit is in the range of 40 to 5
It is preferable that the aliphatic alkylenediamine component unit is in the range of 70 to 95 mol%.
It is preferred that the mole % range and the aromatic diamine component unit be in the range of 30 to 5 mole %. Among the diamine component units (b) constituting the polyamide for the hot melt adhesive composition of the present invention, the aliphatic alkylene diamine component unit has 6 carbon atoms.
to 12 aliphatic alkylene diamines, specifically 1,6-diaminohexane, 1,7-
Diaminoheptane, 1,8-diaminooctane,
Examples of the component units include 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane. Among these aliphatic alkylene diamine component units, 1,6-diaminohexane,
1,8-diaminooctane, 1,10-diaminodecane, 1,12-diaminododecane or a mixed component unit thereof is preferable, particularly 1,
Preferably it is 10-diaminodecane. The alicyclic diamine component units of the diamine component units (b) constituting the polyamide for the hot melt adhesive composition of the present invention are alicyclic diamine component units having 6 to 20 carbon atoms, and are specifically Diaminocyclohexane, cyclohexane bis(methylamine), diaminodicyclohexylmethane,
Isophoronediamine, piperazine, 2,5-dimethylpiperazine, N-aminoethylpiperazine,
Examples include each component such as mensendiamine. Among these alicyclic diamine component units, 1,3-diaminocyclohexane, 1,4
-diaminocyclohexane, 1,3-cyclohexanebis(methylamine), 1,4-cyclohexanebis(methylamine), isophoronediamine,
Piperazine and 2,5-dimethylpiperazine are preferred. Further, the aromatic diamine component unit of the diamine component unit (b) constituting the polyamide for the hot melt adhesive composition of the present invention is an aromatic diamine having 6 to 20 carbon atoms, and specifically Examples of the components include phenylene diamine, xylylene diamine, diaminodiphenylmethane, and diaminodiphenyl ether. Among these aromatic diamine component units, m-phenylene diamine or m-xylylene diamine is preferred. The polyamide used in the hot melt adhesive composition of the present invention can be produced by various conventionally known methods. For example, the polyamide may be described by Paul W. Morgan, Interscience
Published by Publishers (1965), “Polymer
Reviews10, Condensation Polymers, By
Interfacial and Solution Methods” and Von
H. Hopff and A. Krieger, Makromol. Chem.
47, 93-113 (1961), a diacid halide of an aromatic dicarboxylic acid corresponding to the aromatic dicarboxylic acid component unit (a) of the constituent unit of the polyamide and the diamine component unit. It can be produced by polycondensing an aliphatic alkylene diamine and an alicyclic diamine or an aromatic diamine corresponding to (b) by a solution method, or by polycondensing by an interfacial method. You can also do it. Further, the aromatic dicarboxylic acid corresponding to the aromatic dicarboxylic acid component unit (a) of the constituent component units of the polyamide and the diamine component unit (b)
It can also be produced by polycondensing a nylon salt corresponding to 1 by a melt method, or in the case of crystalline polyamide, it can be produced by solid phase polymerization of the oligomer. Polyamide produced by any method can be used in the hot melt adhesive of the present invention. In addition to the above-mentioned essential component polyamide, other components may be added to the hot-melt adhesive composition of the present invention as required. For example, when a powdered inorganic filler is blended, the heat resistance and heat cycle durability of the hot melt adhesive composition improves.
This is preferable because it improves weather resistance and water resistance at high temperatures. Specific examples of the powdered inorganic filler include silica, alumina, silica-alumina, glass powder, quartz powder, red iron powder, titania, zinc oxide, carbon black, iron powder, aluminum powder, stainless steel powder, etc. can. These inorganic fillers can be suitably used unmodified, but those modified with a coupling agent such as silane or titanate can also be suitably used. These powdered inorganic fillers can also be used as a mixture of two or more. The powdered inorganic filler usually has an average particle size of
0.1mμ to 150μ, preferably 1mμ to 150μ
It is in the range of 100μ. Among these powdered inorganic fillers, silica, alumina, silica-alumina, or their titanate coupling modified products improve the heat resistance, heat cycle resistance, weather resistance, and high temperature durability of the adhesive composition. This is particularly suitable since it provides an adhesive with excellent adhesive properties such as water resistance and durability. The blending ratio of the powdered inorganic filler is as follows:
The amount is usually 3 to 150 parts by weight, preferably 5 to 120 parts by weight, and particularly preferably 10 to 100 parts by weight. The hot melt adhesive composition of the present invention contains the polyamide as an essential component,
The composition may include the polyamide and the powdered inorganic filler. Components other than the above-mentioned components that may be added to the hot melt adhesive of the present invention as needed include conventionally known metal adhesives, fillers, lubricants, stabilizers, and the like. Specific examples of conventionally known metal adhesives include the above-mentioned acrylic adhesives, cyanoacrylic adhesives, aliphatic polyamide adhesives such as nylon, aliphatic polyamide/epoxy adhesives, and epoxy adhesives. Examples of adhesives include vinyl phenolic adhesives, nitrile phenolic adhesives, and polyamide adhesives. As for the usage form of the hot melt adhesive of the present invention, as described above, a composition consisting of the polyamide or the powdered inorganic filler blended with the polyamide as required can also be used in a melt-kneaded state. However, it is also possible to adopt a method in which a film, sheet, filament, granule, or powder made of the above-mentioned composition is placed between objects to be adhered, and then heated and compressed using a press. The hot melt adhesive of the present invention can be used to bond adherends such as fibers, stone, porcelain, and glass in addition to metals. Among these adherends, the hot melt adhesive of the present invention is particularly excellent as an adhesive for metals, such as adhesion between metals or adhesion between metals and other adherends. Examples of the metal of the adherend include iron, aluminum, copper, chromium, nickel, titanium, zirconium, tin, zinc, gold, silver, and various alloys containing the above metals. When the hot melt adhesive of the present invention is used to bond metal among the adherends, it is preferable to subject the metal to a surface treatment. As the surface treatment method, various methods are employed depending on the purpose, such as mechanical polishing, chemical treatment, and surface cleaning with a solvent such as trichlorethylene or acetone. When bonding is performed using the hot melt adhesive of the present invention by a thermocompression bonding method, the heat treatment conditions vary depending on the melting point (softening point) of the resin composition containing the polyamide used, but usually the melting point (softening point)
The temperature is from the melting point (softening point) to +100°C, preferably from the melting point (softening point) to the melting point (softening point) +50°C. Applying pressure during bonding increases adhesive strength,
It is suitable for uniformity, but usually 0.1Kg/
cm ² or more, preferably in the range of 0.2 to 10 Kg/cm ² . Next, the hot melt adhesive of the present invention will be specifically explained using examples. The following abbreviations used in Tables 1 and 2 showing Reference Examples, Examples, and Comparative Examples below represent the following compounds, respectively. TA: Terephthalic acid IA: Isophthalic acid C ₆ DA: 1,6-diaminohexane C ₁₀ DA: 1,10-diaminodecane DMP: 2,5-dimethylpiperazine CBM: 1,3-cyclohexane bis(methylamine) IPD: Isophoronediamine MPD: m-phenylenediamine [] Reference example for manufacturing polyamide 1 1,6-diaminohexane 4.36g (37.5mM),
2,5-dimethylpiperazine 1.43g (12.5mM),
15.34 ml of triethylamine (110 mM) and 150 ml of methylene chloride were charged into a four-necked 500 ml flask equipped with a stir bar, a thermometer, and a reflux condenser and stirred at 5° C. under an atmosphere of _N2 . ), isophthaloyl chloride 4.06
A solution of g (40 mM) in methylene chloride (85 ml) was added dropwise over 1 minute. After the dropwise addition, the reaction was carried out at 30°C for 1 hour, and then the reaction mixture was poured into acetone 2, and the precipitated polymer was collected by suction filtration using a glass filter. After thoroughly washing the polymer with warm water and then acetone, it was placed in a vacuum oven at 100°C and 100mmHg.
After drying for one day under these conditions, 10.5 g of polymer was obtained. This polymer _conc.H2SO4 in _solvent
According to NMR analysis, the mole percentages of 1,6-diaminohexane component units in the diamine component units and terephthalic acid component units in the dicarboxylic acid component units in the polymer were 77 and 62, respectively. Also conc.
The intrinsic viscosity [η] at 30℃ in H ₂ SO ₄ is 0.89 dl/
g, the softening point was 330°C. Reference example 2 1,10-diaminodecane 6.46g (37.5mM),
2,5-dimethylpiperazine 1.43g (12.5mM),
15.34 ml of triethylamine (110 mM) and 150 ml of methylene chloride were charged into a four-necked 500 ml flask equipped with a stir bar, a thermometer, and a reflux condenser and stirred at 5° C. under an atmosphere of _N2 . ) of methylene chloride (85ml)
The solution was added dropwise over 1 minute. After the dropwise addition, the reaction was carried out at 30° C. for 1 hour, and then the reaction mixture was poured into acetone 2, and the precipitated polymer was collected by suction filtration using a glass filter. After thoroughly washing the polymer with warm water and then acetone, it was incubated at 100°C in a vacuum oven.
After drying for one day under 100 mmHg, 12.3 g of polymer was obtained. Table 1 shows the mole %, [η], and softening point of the 1,10-diaminodecane component unit in the polymer. Reference Examples 3 to 6 Table 1 as the diamine component unit in Reference Example 2
A polymer was obtained in the same manner as in Reference Example 2, except that the diamines listed were used in the amounts listed in Table 1. The results are shown in Table 1. [Table] [] Preparation of test pieces The polyamide described in the reference example was crushed using a cryo-pulverizer, the 125 mesh pass product alone or a powder blend with the powdered inorganic filler described later, and softened in an _N2 atmosphere using a press molding machine. Compression molding was performed at a temperature 30°C higher than the actual temperature to create a 0.2mm thick press sheet. These press sheets are 100mm long,
Stainless steel plate (SUS) with a width of 10 mm and a thickness of 1 mm.
304, 2B finish, acetone degreasing treatment), narrow at the tip (1 cm ² ), apply a splint and heat to 20℃ from the point.
A tensile shear test piece was prepared by pressing at a high temperature for 10 minutes under a pressure of 5 kg/cm ² , and then cooling at a temperature of 30° C. for 10 minutes under a pressure of 5 kg/cm ² to scrape off the protruding portion. [] Performance evaluation method (1) Tensile shear strength The tensile shear strength measurement test piece was held in an air atmosphere at a specified temperature for 10 minutes, and the test piece was tensile sheared at a tensile speed of 50 mm/min at that temperature. Then, the strength at a predetermined temperature was measured. (2) Heat aging resistance (heat resistance durability) A tensile shear test piece was held at a temperature of 200°C in an air atmosphere for 14 days, then cooled, and the tensile shear strength at 24°C was measured. Also,
without causing thermal deterioration using method (1) above.
The retention rate of heat aging resistance was expressed as a percentage of the tensile shear strength of the heat aged test piece relative to the tensile shear strength measured at 24°C. (3) Boiling water resistance A tensile shear test piece was immersed in boiling tap water at 97-100°C for 7 days, then taken out and heated to 24°C.
was held for 10 minutes, and the tensile shear strength at 24°C was measured. The retention rate of boiling water resistance was expressed as the percentage of the tensile shear strength of the boiling water test piece relative to the tensile shear strength measured at 24° C. without causing boiling water deterioration by the method (1) above. (4) Heat cycle resistance The tensile shear test piece was held at RT, 150℃, RT, and -30℃ for 1 hour each for one cycle, and the tensile shear strength at 24℃ after 100 cycles was measured. It was measured. The above method (1) can be used without causing heat cycle deterioration.
The retention rate of heat cycle durability was expressed as a percentage of the tensile shear strength of the heat cycle resistance test piece relative to the tensile shear strength measured at 24°C. (5) Weather resistance The tensile shear test piece was held in a Sunshine Weatherometer for 1000 hours and then taken out.
Tensile shear strength was measured at 24°C. Said (1)
The retention rate of weathering durability was expressed as the percentage of the tensile shear strength of the weathering durability test piece relative to the tensile shear strength measured at 24° C. without causing deterioration using the method described above. Examples 1 to 8, Comparative Examples 1 to 2 The above tests were carried out using the polyamide shown in Table 2 alone or a composition obtained by blending the polyamide shown in Table 2 and the powdered inorganic filler at the blending ratio shown in Table 2. A piece was prepared and the performance was evaluated. The results are shown in Table 2. The powdered inorganic fillers shown in Table 2 in the following Examples and Comparative Examples are as follows. Note 1 Manufactured by Illinois Mineral Co., trade name IMSIL
A-10 Note 2 Manufactured by Illinois Minerals, trade name IMSIL
A-25 Note 3 Manufactured by Illinois Minerals, trade name IMSIL
K Comparative Example 2 In Example 1, instead of using the polyamide described in Reference Example 1, a film-like nitrile phenolic adhesive (manufactured by Sony Chemical KK, trade name D-3032) was used, and an adhesive of 5 kg/cm ² was used. 200℃ under pressure
The same procedure as in Example 1 was carried out except that the pressure bonding was carried out for 20 minutes.
The results are shown in Table 2. Comparative Example 3 In Example 1, instead of using the polyamide described in Reference Example 1, an epoxy adhesive (manufactured by Cemedine KK, trade name EP-106) was used, and this was applied to a stainless steel plate and stacked to 0.5 kg. A test piece was prepared by curing at 150° C. for 20 minutes under a pressure of /cm ² . The adhesion test was conducted in the same manner as in Example 1. The results are shown in Table 2. [Table] [Table] [Table] [Table]

Claims (1)

[Scope of Claims] 1. An aroma comprising 60 to 100 mol% of terephthalic acid component units and 0 to 40 mol% of aromatic dicarboxylic acid component units selected from isophthalic acid, 2-methylterephthalic acid, and naphthalene dicarboxylic acid. Group dicarboxylic acid component unit (a) and aliphatic alkylene diamine component unit having 6 to 12 carbon atoms in the range of 30 to 95 mol% and 6 to 20 carbon atoms
0 to 150 parts by weight of powdered inorganic filler per 100 parts by weight of polyamide composed of diamine component units (b) consisting of 70 to 5 mol% of alicyclic diamine or aromatic diamine component units. A hot melt adhesive composition containing 2 The blending amount of the powdered inorganic filler is 3 or more.
The hot melt adhesive composition according to claim 1, which contains 150 parts by weight and has an average particle size of 0.1 mμ to 150μ.