JP2017179061A - Easy-disassembly hot-melt composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easy-disassembly hot-melt composition which has good adhesion and easy disassembly to a polypropylene resin, has excellent elasticity of the composition itself, has a small rate of change in reduction of the viscosity even when left at high temperature at 220°C, and has sufficient heat resistance.SOLUTION: An easy-disassembly hot-melt composition contains an SEEPS block copolymer (A) having a weight average molecular weight of 150,000 or more, paraffin oil (B) having kinetic viscosity (40°C) of 100-1,000 mm/s, an aromatic petroleum resin (C) having a softening point of 100°C or higher and a nonpolar tackifier (D), and contains no polypropylene wax.SELECTED DRAWING: None

Description

  The present invention relates to an easily dismantleable hot melt composition.

  Conventionally, as a hot melt composition excellent in sealing property and dismantling property for polyolefin resin, 100 parts by mass of SEEPS (polystyrene-poly (ethylene-ethylene / propylene) -polystyrene block copolymer) having a weight average molecular weight of 250,000 or more. On the other hand, an easily dismantable hot melt composition containing 5 to 500 parts by mass of a terpene phenol resin having a hydroxyl value of 20 to 200 (mgKOH / g) and 350 to 2000 parts by mass of a hydrocarbon-based plasticizer has been proposed. (Patent Document 1).

Japanese Patent No. 4918845

  However, the easy-to-disassemble hot melt composition disclosed in Patent Document 1 is sufficiently easy to peel from general polypropylene resins even though it has excellent sealing properties and dismantling properties for polyolefin resins. There was a tendency not to. In addition, when left at a high temperature of 220 ° C., the rate of change in viscosity drop is large, and heat resistance may be insufficient.

  The problem to be solved by the present invention is that the polypropylene resin has good adhesion and easy peelability, is excellent in elasticity of the composition itself, and has a viscosity even when left at a high temperature of 220 ° C. An object of the present invention is to provide an easily dismantleable hot melt composition having a small rate of change of decrease and sufficient heat resistance.

The present invention includes a SEEPS block copolymer (A) having a weight average molecular weight of 150,000 or more, a paraffin oil (B) having a kinematic viscosity (40 ° C.) of 100 to 1000 mm ² / s, and an aromatic having a softening point of 100 ° C. or more. An easily dismantleable hot melt composition comprising a petroleum petroleum resin (C) and a nonpolar tackifier (D) and not containing polypropylene wax is provided.

  The composition according to the present invention has good adhesion and easy peelability with respect to the polypropylene resin, and is excellent in elasticity of the composition itself, and changes in viscosity decrease even when left at a high temperature of 220 ° C. The rate is small and it has the effect of having sufficient heat resistance.

The composition according to the present invention comprises a SEEPS block copolymer (A) having a weight average molecular weight of 150,000 or more, a paraffin oil (B) having a kinematic viscosity (40 ° C.) of 100 to 1000 mm ² / s, and a softening point of 100 ° C. It contains the above aromatic petroleum resin (C) and a non-polar tackifier (D), and does not contain polypropylene wax. In addition to this, an anti-aging agent, filler, coloring An agent, polyethylene wax, reinforcing material and the like can be blended.

<SEEPS block copolymer>
The SEEPS block copolymer (A) having a weight average molecular weight of 150,000 or more is used as a base polymer of the composition according to the present invention. The weight average molecular weight of the component (A) needs to be 150,000 or more, preferably 150,000 or more and less than 400,000, and preferably 150,000 or more and less than 300,000 as measured by the GPC method. More preferably, it is more preferably 200,000 or more and less than 250,000. Moreover, as a compounding quantity of the said (A) component, it is preferable to mix | blend 1-50 weight% with respect to the whole composition, It is more preferable to mix | blend 3-30 weight%, 5-5 weight% is mix | blended. It is particularly preferred. By being within this range, it is possible to improve the adhesion to the adherend while maintaining the elasticity of the composition itself.

  As styrene content of the said (A) component, it is preferable that it is 10 to 70 weight%, and it is especially preferable that it is 20 to 40 weight%. By being in this range, workability at the time of applying the composition tends to be good, and easy disassembly after application tends to be improved.

<Paraffin oil>
Paraffin oil (B) having a kinematic viscosity (40 ° C.) of 100 to 1000 mm ² / s is intended to suppress the rate of change in viscosity when the composition according to the present invention is left at a high temperature of about 220 ° C. Used. The component (B) is a relatively high molecular weight aliphatic saturated hydrocarbon compound, and its kinematic viscosity needs to be 100 to 1000 mm ² / s as measured at 40 ° C. according to JIS K2283. There is preferably 200 to 800 mm ² / s, more preferably from 300~600mm ² / s, particularly preferably 350~500mm ² / s. Similarly, in measurements at 100 ° C., it is preferably 15~45mm ² / s, more preferably from 20 to 40 mm ² / s, particularly preferably 25 to 35 mm ² / s . By being in this range, workability at the time of applying the composition is improved, and the rate of change in viscosity reduction can be suppressed, so that heat resistance tends to be improved. Examples of commercially available products suitable as the component (B) include Diana Process Oil PW-380 (Idemitsu Kosan Co., Ltd., trade name, kinematic viscosity (40 ° C.): 409 mm ² / s, kinematic viscosity (100 ° C.): 31 mm ² / s. )

  As a compounding quantity of the said (B) component, it is preferable to mix | blend 300-2000 weight part with respect to 100 weight part of said (A) component, It is more preferable to mix | blend 400-1500 weight part, 500-1000 weight Part blending is particularly preferred. By blending within this range, workability at the time of applying the composition is improved, and the rate of change in viscosity reduction can be suppressed, so that the heat resistance tends to be improved.

In addition to the component (B), a paraffin oil having a kinematic viscosity of less than 100 mm ² / s can be blended at a measured value at 40 ° C. according to the above standard within a range not impairing the coating workability and heat resistance. it can. A commercially available product suitable as this component is Diana Process Oil PW-90 (Idemitsu Kosan Co., Ltd., trade name, kinematic viscosity (40 ° C.): 91 mm ² / s, kinematic viscosity (100 ° C.): 11 mm ² / s). .

<Aromatic petroleum resin>
The aromatic petroleum resin (C) having a softening point of 100 ° C. or higher is used for imparting heat resistance to the composition according to the present invention. As a softening point, in the numerical value measured with the thermomechanical analysis method (TMA), it is necessary to be 100 degreeC or more, It is preferable that it is 100 degreeC-250 degreeC, It is more preferable that it is 120 degreeC-200 degreeC, It is especially preferable that it is 140 to 180 degreeC. By being in this range, sufficient heat resistance can be imparted and the elasticity of the composition itself tends to be improved. A commercially available product suitable as the component (C) is Endex 155 (Eastman Chemical Japan, trade name, α-methylstyrene copolymer, softening point: 155 ° C.).

  As a compounding quantity of the said (C) component, it is preferable to mix | blend 30-500 weight part with respect to 100 weight part of said (A) component, It is more preferable to mix | blend 50-400 weight part, 70-300 weight Part blending is particularly preferred. When blended within this range, the elasticity of the composition itself is improved, and the rate of change in viscosity decrease at high temperatures can be suppressed, so that heat resistance tends to be improved.

<Tackifier>
The non-polar tackifiers (D), hydrogenated terpene resins, C ₅ -C ₉ water添脂alicyclic hydrocarbon resin, C ₅ -C ₉ hydrogenated modified alicyclic hydrocarbon resins, cyclopentadiene Based petroleum resins. As a compounding quantity of the said (D) component, it is preferable to mix | blend 10-600 weight part with respect to 100 weight part of said (A) component, It is more preferable to mix | blend 30-400 weight part, 50-200 weight Part blending is particularly preferred. By blending within this range, sufficient tackiness can be imparted to the composition, and the rate of change in viscosity decrease at high temperatures tends to be suppressed.

  In the composition concerning this invention, although said (A)-(D) component is essential, in order to reduce surface tack property, you may mix | blend polyethylene wax further. The component is a chemical substance that is solid at room temperature, and the blending amount thereof is preferably 1 to 100 parts by weight, and 3 to 50 parts by weight based on 100 parts by weight of the component (A). Is more preferable, and 5 to 30 parts by weight is particularly preferable. By blending within this range, the surface tackiness can be sufficiently lowered, and the easy disassembly property to the polypropylene resin tends to be good.

  On the other hand, the composition according to the present invention needs to contain no polypropylene wax. When the said component is mix | blended, when an adherend is a polypropylene, although affinity will become favorable, there exists a tendency for easy disassembly property to deteriorate.

  As other components, an anti-aging agent can be blended to prevent deterioration due to heat. Examples of the component include compounds such as phosphite, naphthylamine, p-phenylenediamine, quinoline, hydroquinone, bis-tris-polyphenol, thiobisphenol, and hindered phenol. Alternatively, two or more kinds can be used in combination. Among these, what used the hindered phenol type of primary antioxidant, and the phosphite type of secondary antioxidant together is preferable. Examples of commercially available products suitable for this component include Nocrack TD (Ouchi Shinsei Chemical Co., Ltd., trade name), Nonflex RD (Seiko Chemical Co., Ltd., trade name), and AL-122 (Kyodo Pharmaceutical Co., Ltd., trade name). Can be mentioned. As a compounding quantity of the said component, it is preferable to mix | blend 0.1-20 weight part with respect to 100 weight part of said (A) component. If it is less than 0.1 part by weight, the effect of preventing thermal deterioration is not sufficient, and even if it exceeds 20 parts by weight, no further effect can be obtained.

Moreover, in addition to filling property, weight reduction, fluidity adjustment, etc., a hollow filler can also be mix | blended for sedimentation prevention. The component should be a glass microballoon, pearlite, silica balloon, alumina balloon, carbon balloon, aluminosilicate balloon having an average particle size (cumulative 50% D ₅₀ by weight) of 100 μm or less and an apparent specific gravity of 1.0 or less. Is preferred. By blending within this range, it is possible to suppress the occurrence of poor appearance or the sedimentation of the filler when the composition according to the present invention melts.

<Examples and Comparative Examples>
In the formulation shown in Table 1, the mixture was sufficiently kneaded at 220 ° C. with a biaxial extruder to obtain easily dismantable hot melt compositions of Examples and Comparative Examples. The raw materials used are shown below.
SEEPS block copolymer: Septon 4055 (Kuraray Co., Ltd., trade name, weight average molecular weight: 230,000, Mw / Mn: 1.3)
Paraffin oil 1: Diana process oil PW-380 (Idemitsu Kosan Co., Ltd., trade name, kinematic viscosity (40 ° C.): 409 mm ² / s, kinematic viscosity (100 ° C.): 31 mm ² / s)
Paraffin oil 2: Diana process oil PW-90 (Idemitsu Kosan Co., Ltd., trade name, kinematic viscosity (40 ° C.): 91 mm ² / s, kinematic viscosity (100 ° C.): 11 mm ² / s)
Aromatic petroleum resin: Endex 155 (Eastman Chemical Japan, trade name, α-methylstyrene copolymer, softening point: 155 ° C.)
Tackifier: Escorez 5320 (ExxonMobil, trade name, hydrogenated alicyclic hydrocarbon resin, softening point 120 ° C. to 130 ° C.)
Polyethylene wax: Sun wax LEL250 (Sanyo Chemical Industries, Ltd., trade name, softening point (JIS K2207): 124 ° C.)
Polypropylene wax: AC-1089 (Honeywell, trade name, dropping point (ASTM D-3954): 146 ° C.)
Anti-aging agent: AL-122 (Kyodo Pharmaceutical Co., Ltd., trade name)
Filler: Scotch K37 (Sumitomo 3M Limited, trade name, hollow glass balloon, average particle size D ₅₀ (50% integrated value by weight): 40 μm)
Colorant: Asahi Thermal Carbon (Asahi Carbon Corporation, trade name, carbon black)

  Moreover, the following physical-property evaluation was performed about the easily decomposable hot-melt composition obtained in the Example and the comparative example. The results are shown in Table 2.

<Viscosity change rate>
13 ml of the easily dismantleable hot melt composition of the example or the comparative example was placed in a cell heated to 220 ° C. with a Brookfield BH viscometer, and after 20 minutes, No. 29 spindles were inserted, the spindle was rotated at 5 rpm, and the value after 20 minutes was taken as the measured value (viscosity A).
Next, 100 g of the easily dismantleable hot melt composition was put into a round can with the lid open, and allowed to stand at 220 ° C. for 24 hours, and the viscosity was measured in the same manner as the measured value (viscosity B).
And the change rate of the viscosity B with respect to the viscosity A was computed. A value within ± 25% was evaluated as ○, and a value exceeding this value was evaluated as ×.

<PP dismantling>
The easily dismantleable hot melt composition of the example or the comparative example was heated to 220 ° C., applied to a polypropylene plate in a bead shape with φ10 mm, and cooled to 20 ° C. Thereafter, the bead-shaped composition was immediately peeled off by hand, and the interface peeling was evaluated as “◯”, and the composition was evaluated as “×”.

<Compression set>
The easily dismantleable hot melt composition of the example or the comparative example was formed to have a diameter of 27 mm and a height of 20 mm, and was sandwiched between two aluminum metal plates having a thickness of 3 mm in the height direction. And it compressed to 10 mm in height, and left still at 80 degreeC for 24 hours. Thereafter, the aluminum metal plate was removed at 20 ° C. to release the compression, and the height for 24 hours after opening (height after opening) was measured with calipers. The compression set (%) was calculated by the following formula, and 50% or less was evaluated as ◯, and more than 50% was evaluated as ×.
Compression set (%) = ((20−height after opening) / 10) × 100

Claims (3)

SEEPS block copolymer (A) having a weight average molecular weight of 150,000 or more;
Paraffin oil (B) having a kinematic viscosity (40 ° C.) of 100 to 1000 mm ² / s;
An aromatic petroleum resin (C) having a softening point of 100 ° C. or higher;
A nonpolar tackifier (D),
An easily dismantleable hot melt composition characterized by not containing polypropylene wax.   Furthermore, polyethylene wax is included, The easily disassembleable hot-melt composition of Claim 1 characterized by the above-mentioned.   The easily dismantable hot melt composition according to claim 1 or 2, wherein the aromatic petroleum resin (C) is an α-methylstyrene copolymer.