JPH05140529A - Adhesive composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition having high bond strength, capable of bonding a polyolefin-based material, which is difficult to stick, without pretreating the material by blending a polyester-based urethane with a chloroprene rubber, a polyisocyanate, etc. CONSTITUTION:(A) An isocyanate-containing polyester-based urethane is blended with (B) a chloroprene rubber, (C) a polyisocyanate (0.1-30 pts.wt. component C is blended based on 100 pts.wt. components A and B), (D) a halogenating agent (preferably alkyl hypohalide etc., and 0.002-20 pts.wt. component D is blended based on 100 pts.wt. solid content of the component A) and (E) 2-ethyl hexoate (e.g. dibutyltin-2-ethylhexoate) to give the objective composition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is used for bonding polyolefin materials, which are difficult to bond, used for automobile parts, bonding materials for electrostatic flocking, and bonding rubber products and synthetic resin products. The present invention relates to an adhesive composition.

[0002]

2. Description of the Related Art Conventionally, as a method for adhering a polyolefin material such as polypropylene which is difficult to adhere to, a method of applying an adhesive after surface treatment with a primer such as chloroprene rubber or an adhesive after performing corona discharge treatment It is known how to apply.

[0003]

However, these adhesion methods require a pretreatment such as a primer treatment or a corona discharge treatment in advance for adhering the polyolefin-based material, so that the number of steps is increased and the workability is poor. Moreover, the adhesive strength was low. An object of the present invention is to solve the above-mentioned conventional problems and to provide an adhesive composition capable of adhering to a polyolefin-based material which is difficult to adhere without pretreatment, and which has high adhesive strength. is there.

[0004]

[Means for Solving the Problems]

In order to achieve the above object, the present invention employs means for forming an adhesive composition from polyester urethane having an isocyanate group, chloroprene rubber, polyisocyanate, a halogenating agent, and 2-ethylhexoates. did.

Polyester urethane is composed of polyisocyanate and polyester polyol, and polyisocyanate is a compound having a plurality of isocyanate groups, such as 2,4-tolylene diisocyanate (TDI) and 65/35 (2,2). The ratio of 4-tolylene diisocyanate to 2,6-tolylene diisocyanate,
The same shall apply hereinafter) Tolylene diisocyanate, 80/20 tolylene diisocyanate, 1,5-naphthalene diisocyanate (NDI), 4,4'-diphenylmethane diisocyanate (MDI), dianisidine diisocyanate, tridene diisocyanate, hexamethylene diisocyanate, xylene diisocyanate ( XDI), meta-xylene diisocyanate, 1,6-hexamethylene diisocyanate (1,6HMDI), hydrogenated 4,4'-
Diphenylmethane diisocyanate, hydrogenated xylene diisocyanate, hydrogenated 2,4-tolylene diisocyanate, hydrogenated 65/35 tolylene diisocyanate, hydrogenated 8
0/20 tolylene diisocyanate, isophorone diisocyanate (IPDI) or the like can be used.

As the polyisocyanate to be blended, in addition to the above polyisocyanates, trifunctional isocyanates 4,4 ', 4''-triphenylmethane triisocyanate (TPMT) and tris (P-isocyanatophenyl) thiophos are used. Fate (TIPP) or the like can be used. The polyisocyanate content is preferably in the range of 0.1 to 30 parts by weight based on 100 parts by weight of the solid content of the polyester urethane and chloroprene rubber. This is because if the compounding ratio is less than 0.1 parts by weight, the improvement in the adhesive strength is small, and if it exceeds 30 parts by weight, the improvement in the adhesive strength cannot be expected.

As the polyester polyol, polybutylene adipate (PBA), polyethylene butylene adipate (PEBA), polyethylene adipate (PE
T), polyethylene sebacate (PESE) T, etc. can be used.

As the halogenating agent, for example, t-butyl hypochloride (t-BHC) as an alkyl hypohalide, and sodium hypochlorite, potassium hypochlorite, in the molecule as a hypohalogen acid salt. -CON
As the compound having an X-bond, N-bromosuccinimide (NBSI), isocyanuric trichloride (TCIA),
Isocyanuric dichloride (DiCIA), other, antimony pentafluoride, a mixed solution of sulfur fluoride and bromine, and the like can be used. Among them, alkyl hypohalide, hypohalite, or -CONX in the molecule is used. Compounds having a bond are preferred. The mixing ratio of the halogenating agent is preferably 0.002 to 20 parts by weight with respect to 100 parts by weight of the solid content of the polyester urethane. This is because when the blending ratio is less than 0.002 parts by weight, the degree of halogenation is small and the improvement in adhesive strength is small.
This is because the stability of the adhesive composition deteriorates if it exceeds the weight part.

Examples of 2-ethylhexoates include (1) dibutyltin di-2-ethylhexoate (2) red, 2-ethylenehexoate (Pb 24
%) (3) Tetra (2-ethylhexyl) titanate (4) Secondary 2-ethylhedisoate iron (Fe 6%) (5) Cobalt 2-ethylhexoate (Co 6%) etc. were used (( The numbers in parentheses correspond to the numbers of 2-ethylhexoates in the examples).

The mixing ratio of the chloroprene rubber is a weight ratio of polyester type urethane / chloroprene rubber =
It can be arbitrarily set as 2 to 98/98 to 2.

If desired, a chain extender, a solvent and a phenol resin may be used. As the chain extender, butylene glycol (BG), 1,6-hexanediol (1,6HD), ethylene glycol ( EG), propylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol. , Neopentyl glycol, etc., or a mixture of two or more thereof can be used. As a solvent,
For example, n-hexane, n-heptane, n-octane as an aliphatic hydrocarbon, cyclohexane, cyclooctane as an alicyclic hydrocarbon, benzene, ethylbenzene, toluene, xylene, an acetone as an aromatic hydrocarbon, and acetone , Methyl ethyl ketone, ethyl propyl ketone, methyl butyl ketone, tetrahydrofuran as ethers, methyl acetate as acetic ester,
Ethyl acetate, isopropyl acetate, halogenated hydrocarbons such as methylene chloride, 1,1,1-trichloroethane, trichloroethylene, other dimethyl sulfoxide (DMSO), dimethylformamide (DM
F), etc. And these solvents are used individually or as a mixed solvent of 2 or more types, and the compounding ratio of an adhesive composition and these solvents is also set arbitrarily. Examples of the phenolic resin include novolac type alkylphenols such as Tamanor 510 (trade name, manufactured by Arakawa Chemical Co., Ltd.).
As Tamanor 515, Tamanor 803, Tamanor 526, Tamanor 528, Resol type alkylphenol,
Tamanoru 520S, Tamanoru 521, Tamanoru 573,
As a Tamanor 577, Tamanor 586, and Tamernor 803 can be used as a terpene type alkylphenol.

[0013]

According to the above-mentioned constitution, even if the adhesive composition is directly applied between the two polyolefin materials which are difficult to adhere to each other without pretreatment, these polyolefin materials are firmly adhered.

[0014]

EXAMPLES Examples using the adhesive composition of the present invention will be described below in comparison with comparative examples. First, a polyester-based urethane having an isocyanate group was synthesized in the following blending ratio. Polyester-based urethane PBA (number average molecular weight 50 to 100 parts by weight of MDI)
0) 66.56 parts by weight were mixed in trichloroethylene and reacted at 80 ^O C for 3 hours in a dry nitrogen gas atmosphere to synthesize a polyester urethane prepolymer. Then, 20.40 parts by weight of BG was added to this polyester-based urethane prepolymer and reacted at 80 ^O C for 20 minutes to synthesize a polyester-based urethane. The polyester-based urethane obtained had a solid content of 25% and trichloroethylene of 75%. Polyester urethane PEBA (number average molecular weight 2
000) 266.31 parts by weight were mixed in trichloroethylene and reacted at 80 ^O C for 3 hours in a dry nitrogen gas atmosphere to synthesize a polyester urethane prepolymer. Then, 26.76 parts by weight of 1,6HD was added to the polyester-based urethane prepolymer and reacted at 80 ^O C for 20 minutes to synthesize a polyester-based urethane.
The polyester-based urethane obtained had a solid content of 25% and trichloroethylene of 75%. Polyester urethane PEA (number average molecular weight 10
(00) 191.94 parts by weight was mixed in trichloroethylene and reacted at 80 ^O C for 3 hours in a dry nitrogen gas atmosphere to synthesize a polyester urethane prepolymer. After that, 44.09 parts by weight of EG was added to this polyester-based urethane prepolymer and reacted at 80 ^O C for 20 minutes to synthesize a polyester-based urethane. The polyester-based urethane obtained had a solid content of 25% and trichloroethylene of 75%. Polyester urethane 1,6 HMDI 100 parts by weight, PESe (number average molecular weight 1000) 99.10 parts by weight is mixed in trichloroethylene, and the mixture is heated to 80 ^O C in a dry nitrogen gas atmosphere.
Were reacted for 3 hours to synthesize a polyester-based urethane prepolymer. Then, 28.92 parts by weight of EG was added to this polyester urethane prepolymer and reacted at 80 ^O C for 20 minutes to synthesize a polyester urethane.
The polyester-based urethane obtained had a solid content of 25% and trichloroethylene of 75%. Polyester urethane PEA (number average molecular weight 10
00) 266.31 parts by weight was mixed in trichloroethylene and reacted at 80 ^O C for 3 hours in a dry nitrogen gas atmosphere to synthesize a polyester urethane prepolymer. Then, 5.79 parts by weight of EG was added to this polyester-based urethane prepolymer and reacted at 80 ^O C for 20 minutes to synthesize a polyester-based urethane. The polyester-based urethane obtained had a solid content of 25% and trichloroethylene of 75%. Next, with respect to the solid content of the polyester-based urethane shown in these ~, chloroprene rubber,
An adhesive composition was obtained by blending polyisocyanate, a halogenating agent and 2-ethylhexoates in a predetermined ratio.

2 parts by weight of chloroprene rubber (CR), 0.1 part by weight of MDI, 2-ethylhexoate (1) based on 98 parts by weight of the polyester urethane of (Example 1).
An adhesive composition was obtained by blending 0.05 part by weight and 0.002 part by weight of t-BHC. 20 parts by weight of chloroprene rubber (CR), 80 parts by weight of polyester-based urethane of (Example 2), MDI3
An adhesive composition was obtained by blending 0 parts by weight, 0.01 parts by weight of 2-ethylhexoate (1), and 1 part by weight of t-BHC. 40 parts by weight of chloroprene rubber (CR), 60 parts by weight of XDI1 with respect to 60 parts by weight of the polyester-based urethane of (Example 3)
0 parts by weight, 2-ethylhexoate (1) 0.1 parts by weight,
And 1 part by weight of NBSI were blended to obtain an adhesive composition. To 40 parts by weight of the polyester-based urethane of (Example 4), 60 parts by weight of chloroprene rubber (CR), TDI1
0 part by weight, 2-ethylhexoate (1) 0.5 part by weight,
And 1 part by weight of TCIA were blended to obtain an adhesive composition. Chloroprene rubber (CR) 80 parts by weight, IPDI to 20 parts by weight of the polyester-based urethane of (Example 5)
An adhesive composition was obtained by blending 10 parts by weight, 0.05 parts by weight of 2-ethylhexoate (2), and 20 parts by weight of TCIA. 98 parts by weight of chloroprene rubber (CR), TPMT1 against 2 parts by weight of the polyester-based urethane of (Example 6)
An adhesive composition was obtained by blending 0 parts by weight, 0.05 parts by weight of 2-ethylhexoate (3), and 1 part by weight of TCIA. To 60 parts by weight of the polyester-based urethane of (Example 7), 40 parts by weight of chloroprene rubber (CR), TPMT
An adhesive composition was obtained by blending 10 parts by weight, 0.05 parts by weight of 2-ethylhexoate (4), and 1 part by weight of TCIA. To 60 parts by weight of the polyester-based urethane of (Example 8), 40 parts by weight of chloroprene rubber (CR), TIPP
An adhesive composition was obtained by blending 10 parts by weight, 0.05 parts by weight of 2-ethylhexoate (5), 1 part by weight of TCIA, and 20 parts by weight of Tamanol 803. To 60 parts by weight of the polyester-based urethane of (Example 9), 40 parts by weight of chloroprene rubber (CR), TIPP
An adhesive composition was obtained by blending 10 parts by weight, 0.05 parts by weight of 2-ethylhexoate (1), 1 part by weight of TCIA, and 10 parts by weight of Tamanol 340.

Next, in order to examine the adhesive strength of the adhesive composition thus obtained, the following moisture-resistant peeling test was conducted. The number of test pieces used for this moisture-resistant peeling test is 2
The adhesive composition was applied to a 25 × 25 mm bonding area on a piece of polyethylene 5 × foam test piece, and 100 ^O C was applied.
After heating for 2 minutes to evaporate the solvent, a load of 5 kg / cm ² is applied for adjustment, and the obtained test piece is allowed to stand at 50 ^O C in 98% relative humidity for 200 hours. It was pulled at a pulling speed of 50 mm / min to measure the moisture-resistant peel strength. The results are shown in Table-1. (Below margin)

[0017]

[Table 1]

Further, Comparative Examples 1 to 3 are obtained by the following formulations. An adhesive composition obtained only with the polyester-based urethane of (Comparative Example 1). Comparative Example 2 An adhesive composition obtained by mixing 50 parts by weight of MDI and 1 part by weight of TCIA with 100 parts by weight of chloroprene rubber (CR). 40 parts by weight of chloroprene rubber (CR), 60 parts by weight of polyester-based urethane of (Comparative Example 3), MDI1
An adhesive composition obtained by blending 0 part by weight.

As is clear from Table 1, isocyanate
The adhesive composition in which the polyester urethane having a group, chloroprene rubber, polyisocyanate, a halogenating agent, and 2-ethylhexoate is mixed is such that the foam that is five times as large as the adherend polyethylene bursts. It can be seen that the peel strength is high.

The reason why the adhesive composition of the present invention exhibits such an excellent adhesive strength is that the halogen in the halogenating agent halogenates the polyolefin having no polarity of the adherend, and By increasing the intermolecular force of both by halogenating the polyester-based urethane of, the peel strength is improved by the flexible and elastic chloroprene rubber, further, the isocyanate group of the polyester urethane and the isocyanate of polyisocyanate It is considered that the synergistic action with the base further improves the adhesive strength. On the other hand, as shown in Comparative Examples 1 to 3, when any of the above-mentioned polyester-based urethane, chloroprene rubber, polyisocyanate, and halogenating agent is not blended, the stability of the adhesive composition is It can be seen that the adhesive strength is poor or the adhesive strength is extremely low. In this embodiment, not only the conventionally used primer can be easily bonded to each other, which is difficult to bond, but also the bonding strength is extremely high.
Therefore, the adhesive composition of this example is suitably used, for example, in automobile moldings in which polyolefin-based materials are used, substrates for electrostatic flocking, interior parts, rubber products, and the like.

[0021]

As described in detail above, the adhesive composition of the present invention is not only capable of adhering to a polyolefin-based material which is particularly difficult to adhere without pretreatment, but also has an adhesive strength. It has an excellent effect of being extremely high.

Claims (1)

[Claims] 1. A polyester-based urethane having an isocyanate group, chloroprene rubber, polyisocyanate,
An adhesive composition comprising a halogenating agent and 2-ethylhexoates.