JPH04164986A - Adhesive composition - Google Patents

Abstract

PURPOSE:To provide an adhesive composition capable of firmly bonding a polyolefinic material without pretreating by mixing an isocyanate-containing polyester-based urethane, a chloroprene rubber, an alcoholate and a halogenating agent. CONSTITUTION:An isocyanate-containing polyester-based urethane is prepared by reacting a polyisocyanate such as 2,4-tolylene diisocyanate with a polyesterpolyol such as polybutylene adipate. An adhesive composition is prepared by mixing this urethane with a chloroprene rubber, a polyisocyanate, an alcoholate such as sodium methylate, and a halogenating agent such as sodium hypochlorite. This adhesive composition is suitably used for bonding a difficult-to-bond polyolefinic material which is used as the parts of an automobile.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to adhesion of polyolefin materials that are difficult to adhere to, such as those used as automobile parts, adhesion of materials for electrostatic flocking, rubber products, and synthetic resins. The present invention relates to an adhesive composition used for adhering products.

<Prior art> Conventional methods for bonding polyolefin materials such as polypropylene, which are difficult to bond, include applying adhesive after surface treatment with a primer such as chloroprene rubber, or applying adhesive after corona discharge treatment. Is there any known way to do this?

However, these bonding methods require pretreatment such as primer treatment and corona discharge treatment before bonding polyolefin materials, which increases the number of steps and results in poor workability. Not only that, but the adhesive strength was also low.

The purpose of the present invention is to solve the above-mentioned conventional problems, and to provide an adhesive composition that can be bonded to polyolefin materials that are difficult to bond without pretreatment and that has high adhesive strength. be.

Means for Solving the Problems To achieve the above objects, the present invention provides an adhesive composition comprising a polyester urethane having an isocyanate group (-NCO), chloroprene rubber, polyisocyanate, alcoholade, and a halogenating agent. The method of doing so was adopted.

Polyester urethane is composed of polyisocyanate and polyester polyol, and polyisocyanate is a compound having multiple isocyanate groups, such as 2,4-tolylene diisocyanate (TD I).
, 65/35 (ratio of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, the same applies 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), metaxylene diisocyanate, 1,6-hexamethylene diisocyanate (1°6HMDI), hydrogenated 4,4°-diphenylmethane diisocyanate, water Added xylene diisocyanate, hydrogenated 2,4-tolylene diisocyanate, hydrogenated 65/35 tolylene diisocyanate, hydrogenated 80/
20 tolylene diisocyanate, inphorone diisocyanate (IPDI), etc. can be used.

In addition to the above-mentioned polyisocyanates, the polyisocyanates to be blended include trifunctional isocyanate 4
, 4', 4''-triphenylmethane triincyanate (TPMT), tris(P-isocyanate phenyl) thiophosphate (TIPP), etc. can be used.The blending ratio of this polyisocyanate is Based on 100 parts by weight of the solid content of the urethane and chloroprene rubber, the range is preferably from 0.1 to 30 parts by weight.This is because if the blending ratio is less than 0.1 parts by weight, there will be little improvement in adhesive strength; This is because if the adhesive strength exceeds this value, a factory with high adhesion strength cannot be expected.

Polyester polyols include polybutylene adipate (PBA) and polyethylene butylene adipate (P
EBA), polyethylene adipate (PEA), polyethylene sebacate (PESe), etc. can be used.

Further, as a halogenating agent, for example, as an alkyl hypohalide, t-butyl hypochloride (t-BH
C), sodium hypochlorite and potassium hypochlorite as hypohalites; N-bromosuccinimide (NBS) as a compound having -CONX- bond in the molecule;
I), isocyanuric acid trichloride (TCA), isocyanuric acid dichloride (DiCIA), antimony pentafluoride, a mixed solution of sulfur fluoride and bromine, etc. can be used, but among these, alkyl hypo Halides, hypohalites, or compounds having a -CONX- bond in the molecule are preferred. The blending ratio of the halogenating agent is preferably in the range of 0.002 to 20 parts by weight based on 100 parts by weight of the solid content of the polyester urethane. This is because if the blending ratio is less than 0.002 parts by weight, the degree of chlorination will be small, resulting in little improvement in adhesive strength, and if it exceeds 20 parts by weight, the stability of the adhesive composition will deteriorate.

Alcoholades include sodium methylate, potassium methylate, lithium methylate, sodium ethylate, potassium ethylate, lithium ethylate, sodium propinate, potassium propinate, lithium propinate, and the like.

In addition, the blending ratio of chloroprene rubber is polyester urethane/chloroprene rubber = 2 to 98/9 by weight.
It can be set arbitrarily, such as from 8 to 2.

In addition, a chain extender, a solvent, and a phenol resin may be used if desired, and examples of the chain extender include butylene glycol (BG), 1,6-hexanediol (1,6HD)
, ethylene glycol (EG), propylene glycol, butanediol 1.4, butanediol 1,3, butanediol 2.3, diethylene glycol, dipropylene glycol, triethylene glycol, bentanediol 1,5, hexanediol 1,6, One or a mixture of two or more of neopentyl glycol and the like can be used.

Examples of solvents include aliphatic hydrocarbons such as n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclohexane and cyclooctane; and aromatic hydrocarbons such as benzene, ethylbenzene, toluene, xylene, and ketone. Examples include acetone, methyl ethyl ketone, ethyl propyl ketone, methyl butyl ketone, ethers, tetrahydrofuran, acetic acid esters, methyl acetate, ethyl acetate, isopropyl acetate, halogenated hydrocarbons, methylene fluoroid, 1.1.
Examples include 1-trichloroethane, trichloroethylene, dimethyl sulfoxide (DMSO), and dimethylformamide. These solvents may be used alone or as a mixed solvent of two or more, and the blending ratio of the adhesive composition and these solvents may also be set arbitrarily.

Examples of phenolic resins include novolak-type alkylphenols such as Tamanol 510, Tamanol 515, Tamanol 803, and Tamanol 5 manufactured by Arakawa Chemical Co., Ltd.
26, Tamanol 528, resol type alkylphenol such as Damanol 520S1 Tamanol 5211 Tamanol 573, Tamanol 577, Tamanol 586, and terpene type alkylphenol such as Tumanol 803 can be used.

Effect> According to the above-described configuration, even if the adhesive composition is directly applied between two polyolefin materials that are difficult to adhere to without pretreatment, these polyolefin materials are firmly adhered.

<Examples> Examples using the adhesive composition of the present invention will be described below in comparison with comparative examples.

First, a polyester urethane having isocyanate groups was synthesized at the following blending ratio.

66.56 parts by weight of PBA (number average molecular weight 500) was mixed with 1100 parts by weight of polyester urethane ■ ~ ID in trichlorethylene, and the mixture was reacted at 80°C for 3 hours in a dry nitrogen gas atmosphere to form a polyester urethane preform. The polymer was synthesized. Thereafter, 20.40 parts by weight of BG was added to this polyester urethane prepolymer and reacted at 80° C. for 20 minutes to synthesize a polyester urethane. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%.

Polyester urethane ■ 100 parts by weight of MDI and 266.31 parts by weight of PEBA (number average molecular weight 2000) were mixed in trichlorethylene and reacted at 80°C for 3 hours in a dry nitrogen gas atmosphere to form a polyester urethane prepolymer. Synthesized. Thereafter, 26.76 parts by weight of 1,6HD was added to this polyester-based urethane prepolymer, and the mixture was heated to 80°C.
The reaction was carried out for 0 minutes to synthesize polyester urethane. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%.

Polyester urethane■ PEA (number average molecular weight 1
000) were mixed in trichlorethylene and reacted at 80° C. for 3 hours in a dry nitrogen gas atmosphere to synthesize a polyester-based urethane prepolymer. Thereafter, 44.09 parts by weight of EG44.0 was added to this polyester urethane prepolymer and reacted at 80°C for 20 minutes to synthesize a polyester urethane. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%.

Polyester urethane■ 1.6HMD 1100 parts by weight and PE5e (number average molecular weight 1000) 99.10 parts by weight were mixed in trichlorethylene and heated at 80°C in a dry nitrogen gas atmosphere.
The mixture was reacted for 3 hours to synthesize a polyester urethane prepolymer. Then, 28.92 parts by weight of EG was added to this polyester-based urethane prepolymer and
The reaction was carried out for 0 minutes to synthesize polyester urethane. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%.

Polyester urethane■ PEA (number average molecular weight 1
000) were mixed in trichlorethylene and reacted at 80° C. for 3 hours in a dry nitrogen gas atmosphere to synthesize a polyester-based urethane prepolymer. Thereafter, 5.79 parts by weight of EG was added to this polyester urethane prepolymer and reacted at 80° C. for 20 minutes to synthesize a polyester urethane. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%.

Next, for the solid content of polyester urethane shown in these ■～■, chloroprene rubber, polyisocyanate,
An adhesive composition was obtained by blending a halogenating agent and a phenol resin in predetermined proportions.

(Example 1) To 98 parts by weight of polyester urethane (2), 2 parts by weight of chloroprene rubber (CR), 1 part by weight of MDIo, 0.01 part by weight of sodium methylate) and t-BHCo,
002 parts by weight was blended to obtain an adhesive composition.

(Example 2) CR2 for 80 parts by weight of polyester urethane
0 parts by weight, 30 parts by weight of MD I, 0.1 parts by weight of sodium methylate, and 1 part by weight of t-BHC to obtain an adhesive composition.

(Example 3) CR4
0 parts by weight of XD I, 1-0.01 parts by weight of sodium ethyl, and 1-0.01 parts by weight of NBSII to obtain an adhesive composition.

(Example 4) CR6 to 40 parts by weight of polyester urethane
0 parts by weight, TDIIO parts by weight, sodium ethylate 0
．． An adhesive composition was obtained by blending 1 part by weight and 1 part by weight of TCIAI.

(Example 5) CR8 for 20 parts by weight of polyester urethane (1)
0 parts by weight, IPDIIO parts by weight, potassium methylate 0
．． An adhesive composition was obtained by blending 1 part by weight and 20 parts by weight of TCIA.

(Example 6) CR98 to 2 parts by weight of polyester urethane (2)
Parts by weight, parts by weight of TPMTIO, 0.0 parts by weight of potassium ethylate.
An adhesive composition was obtained by blending 1 part by weight and 1 part by weight of TCIAI.

(Example 7) CR4 for 60 parts by weight of polyester urethane
0 parts by weight, 10 parts by weight of TPMT, 1 part by weight of TCIA,
0.1 parts by weight of lithium ethylate and Tamanol 520S
An adhesive composition was obtained by blending 1 part by weight of the following.

(Example 8) CR4 for 60 parts by weight of polyester urethane (1)
0 parts by weight, 0 parts by weight of TlPPl, 1 part by weight of TCIA, 0.01 parts by weight of sodium propine) and Tamanol 80
An adhesive composition was obtained by blending 20 parts by weight of No. 3.

(Example 9) CR4 for 60 parts by weight of polyester urethane
0 parts by weight, 0 parts by weight of TlPPl, 1 part by weight of TCIA, 0.01 parts by weight of potassium propinate, and Tamanol 340
An adhesive composition was obtained by blending 10 parts by weight of the following.

Next, in order to examine the adhesive strength of the adhesive composition thus obtained, the following moisture peel test was conducted.

The test pieces used for this moisture peel test were made by applying the adhesive composition to an adhesion area of 25 x 25 mm on two test pieces made of 5x polyethylene foam, and heating the adhesive composition at 100°C for 2 minutes to evaporate the solvent. , pasted together 5 kg/
The cvl was left at 50° C. and 98% relative humidity for 200 hours, and then pulled at a pulling speed of 50 mm/min to measure the moisture peel strength. The results are shown in Table-1.

(The following is a blank space) Table 1 Comparative Examples 1 to 3 were obtained using the following formulations.

(Comparative Example 1) Adhesive composition obtained only from polyester urethane (1).

(Comparative Example 2) For 100 parts by weight of CR, 50 parts by weight of MDI, TCIA
An adhesive composition obtained by blending 1 part by weight.

(Comparative Example 3) CR4 for 60 parts by weight of polyester urethane
An adhesive composition obtained by blending 0 parts by weight and MDIIO parts by weight.

As is clear from Table 1, the adhesive composition containing isocyanate group-containing polyester urethane, chloroprene rubber, polyisocyanate, and a halogenating agent causes the foam to rupture five times as much as the polyethylene adherend. It can be seen that the higher the peel strength, the greater the peel strength.

The reason why the adhesive composition of the present invention exhibits such excellent adhesive strength is that the halogen in the halogenating agent halogenates the non-polar polyolefin of the adherend, and the polyester base in the adhesive composition By halogenating the urethane, the intermolecular force between both sides is increased, and the peel strength is improved by using flexible and elastic chloroprene rubber.Furthermore, the isocyanate group of the polyester urethane is replaced with the inocyanate group of the polyisocyanate. This is thought to be due to the synergistic effect of the two to further improve the adhesive strength.

On the other hand, as shown in Comparative Examples 1 to 3, when any of the aforementioned polyester urethane, chloroprene rubber, polyisocyanate, and halogenating agent is not blended, the stability of the adhesive composition is poor. It can be seen that the adhesive strength is extremely low.

Now, in this example, not only can polyethylenes, which are difficult to adhere to each other, be easily adhered to each other without using a conventionally used primer, but also the adhesive strength is extremely high. Therefore, the adhesive composition of this example is suitably used for, for example, automobile moldings, base materials for electrostatic flocking, interior parts, rubber products, etc. in which polyolefin materials are used.

<Effects of the Invention> As detailed above, the adhesive composition of the present invention is not only capable of adhering to polyolefin materials that are particularly difficult to adhere to without pretreatment, but also has excellent adhesive strength. It has an excellent effect of being extremely high.

Claims (1)

[Claims] 1. An adhesive composition comprising a polyester urethane having an isocyanate group (-NCO), chloroprene rubber, polyisocyanate, Alcolade, and a halogenating agent.