JPH04293988A - Adhesive composition - Google Patents

Abstract

PURPOSE:To provide an adhesive composition which makes it possible to bond a polyolefinic material, which is difficult to bond, with high bonding strength without pretreatment. CONSTITUTION:An adhesive composition which consists of a polyester urethane having isocyanate groups, a chloroprene rubber, a polyisocyanate, a halogenating agent, and morpholine. This composition makes it possible to firmly bond a polyolefinic material with excellent moisture-resistant peel strength without pretreatment such as primer treatment or corona discharge treatment.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is applicable to, for example, adhesion of difficult-to-adhesion polyolefin materials used as automobile parts, adhesion of materials for electrostatic flocking, and adhesion of rubber products and synthetic resin products. The present invention relates to an adhesive composition.

0002

[Prior Art] Conventionally, methods for adhering polyolefin-based materials such as polypropylene, which are difficult to adhere to, include applying adhesive after surface treatment with a primer such as chloroprene rubber, or applying adhesive after corona discharge treatment. There are known methods to do this.

0003

[Problems to be Solved by the Invention] 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 degrades workability. Moreover, the adhesive strength was also low.

An object of the present invention is to solve the above-mentioned conventional problems and provide an adhesive composition that can be bonded to polyolefin materials that are difficult to bond without pretreatment and that has high adhesive strength. It's about doing.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an adhesive composition composed of polyester urethane having an isocyanate group (-NCO), chloroprene rubber, polyisocyanate, a halogenating agent, and morpholines. 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 (
TDI), 65/35 (ratio of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, hereinafter the same) 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, hydrogenated xylene diisocyanate, hydrogenated 2, 4-Tolylene diisocyanate, hydrogenated 65/35 tolylene diisocyanate, hydrogenated 80/2
0-tolylene diisocyanate, isophorone diisocyanate (IPDI), etc. can be used.

In addition to the above-mentioned polyisocyanates, the polyisocyanates to be blended include 4,4',4''-triphenylmethane triisocyanate (TPMT), which is a trifunctional isocyanate, and tris(P-isocyanate phenyl) thiophos. Fate (TIPP) etc. can be used. The blending ratio of this polyisocyanate 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 blending ratio is less than 0.1 parts by weight, the improvement in adhesive strength will be small, and if it exceeds 30 parts by weight, no improvement in adhesive strength can be expected.

[0008] Polyester polyols include polybutylene adipate (PBT), polyethylene butylene adipate (PEBA), and polyethylene adipate (PE
T), polyethylene sebacate (PESE) T, etc. can be used.

In addition, examples of halogenating agents include t-butylhypochloride (t-BHC) as an alkyl hypohalide, sodium hypochlorite and potassium hypochlorite as hypohalites, and sodium hypochlorite and potassium hypochlorite as hypohalites. -CON
As a compound having an X-bond, N-bromosuccinimide (NBSI), trichloroisocyanuric acid (TCIA),
Isocyanuric acid dichloride (DiCIA), antimony pentafluoride, a mixed solution consisting of sulfur fluoride and bromine, etc. can be used, but among these, alkyl hypohalides, hypohalites or -CONX in the molecule can be used. - Compounds having a bond 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 halogenation is small, so the improvement in adhesive strength is small;
This is because if the amount exceeds parts by weight, the stability of the adhesive composition deteriorates.

Examples of morpholines include those shown in Chemical Formula 1 and Table 1. Further, the blending ratio of chloroprene rubber can be arbitrarily set in terms of weight ratio, such as polyester urethane/chloroprene rubber = 2 to 98/98 to 2. Incidentally, a chain extender, a solvent and a phenol resin may be used as desired, and as the chain extender,
Butylene glycol (BG), 1,6-hexanediol (1,6HD), ethylene glycol (EG), propylene glycol, 1,4-butanediol, 1,3-
One or two of butanediol, 2,3-butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, etc.
Mixtures of more than one species can be used.

Examples of the solvent include aliphatic hydrocarbons such as n-hexane, n-heptane, and n-octane, and alicyclic hydrocarbons such as cyclohexane, cyclooctane,
Aromatic hydrocarbons: benzene, ethylbenzene, toluene, xylene; ketones: acetone, methyl ethyl ketone, ethyl propyl ketone, methyl butyl ketone; ethers: tetrahydrofuran; acetic acid esters: methyl acetate, ethyl acetate, isopropyl acetate, halogens Examples of carbonized hydrocarbons include methylene chloride, 1,1,1-trichloroethane, trichloroethylene, dimethyl sulfoxide (DMSO), dimethyl formamide (DMF), and the like. 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.

As the phenol resin, as a novolac type alkylphenol, for example, Tamanol 510, Tamanol 515, Tamanol 803 manufactured by Arakawa Chemical Co., Ltd.
, Tamanol 526, Tamanol 528, resol type alkylphenol, Tamanol 520S, Tamanol 52
1, Tamanol 573, Tamanol 577, Tamanol 586
, Tamanol 80 as a terpene type alkylphenol
3 etc. can be used.

[0013]

[Operation] According to the above-described structure, even if the adhesive composition is directly applied between two polyolefin materials that are difficult to bond to each other without any pretreatment, these polyolefin materials can be firmly bonded.

[0014]

[Examples] Hereinafter, examples using the adhesive composition of the present invention will be explained in comparison with comparative examples. First, a polyester urethane having isocyanate groups was synthesized at the following blending ratio. Polyester urethane ■ PBA (number average molecular weight 50 parts by weight) for 100 parts by weight of MDI
0) 66.56 parts by weight were mixed in trichlorethylene and reacted for 3 hours at 80 OC in a dry nitrogen gas atmosphere to synthesize a polyester-based urethane prepolymer. Thereafter, 20.40 parts by weight of BG was added to this polyester urethane prepolymer and reacted at 80 OC 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■ PEBA (number average molecular weight 2
000) were mixed in trichlorethylene and reacted for 3 hours at 80 OC in a dry nitrogen gas atmosphere to synthesize a polyester-based urethane prepolymer. Then, 26.76 parts by weight of 1,6HD was added to this polyester-based urethane prepolymer to give 80%
A polyester urethane was synthesized by reacting with OC for 20 minutes. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%. Polyester urethane■ PEA (number average molecular weight 10
00) 191.94 parts by weight were mixed in trichlorethylene and reacted for 3 hours at 80OC in a dry nitrogen gas atmosphere to synthesize a polyester-based urethane prepolymer. Thereafter, 44.09 parts by weight of EG was added to this polyester-based urethane prepolymer and reacted at 80OC for 20 minutes to synthesize a polyester-based urethane. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%. Polyester urethane ■ 99.10 parts by weight of PESe (number average molecular weight 1000) was mixed with 100 parts by weight of 1,6HMDI in trichlorethylene, and the mixture was heated to 80 O in a dry nitrogen gas atmosphere.
A polyester-based urethane prepolymer was synthesized by reacting at C for 3 hours. Then, 28.92 parts by weight of EG was added to this polyester-based urethane prepolymer to give 80%
A polyester urethane was synthesized by reacting with OC for 20 minutes. The obtained polyester urethane had a solid content of 25% and a trichlorethylene content of 75%. Polyester urethane ■ PEA (number average molecular weight 10 parts by weight) for 100 parts by weight of MDI
00) 266.31 parts by weight were mixed in trichlorethylene and reacted for 3 hours at 80OC 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 OC 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, chloroprene rubber, polyisocyanate, a halogenating agent, and a phenol resin were blended in predetermined proportions to the solid content of the polyester urethanes shown in (1) to (4) to obtain an adhesive composition.

(Example 1) 2 parts by weight of chloroprene rubber (CR), 0.1 part by weight of MDI, and 0.01 part by weight of morpholine (1) (shown in Table 1) were added to 98 parts by weight of the polyester urethane (1). , and 0.002 parts by weight of t-BHC to obtain an adhesive composition.

(Example 2) 20 parts by weight of chloroprene rubber (CR), 30 parts by weight of MDI, 0.1 part by weight of morpholine (2) (shown in Table 1), and 80 parts by weight of polyester urethane (2). An adhesive composition was obtained by blending 1 part by weight of t-BHC.

(Example 3) 40 parts by weight of chloroprene rubber (CR), 10 parts by weight of XDI, 0.5 parts by weight of morpholine (3) (shown in Table 1), and 60 parts by weight of polyester urethane (3) An adhesive composition was obtained by blending 1 part by weight of NBSI.

(Example 4) 60 parts by weight of chloroprene rubber (CR), 10 parts by weight of TDI, 0.05 parts by weight of morpholine (4) (shown in Table 1), and An adhesive composition was obtained by blending 1 part by weight of TCIA.

(Example 5) 80 parts by weight of chloroprene rubber (CR), 10 parts by weight of IPDI, 0.01 parts by weight of morpholine (5) (shown in Table 1), and An adhesive composition was obtained by blending 20 parts by weight of TCIA.

(Example 6) 98 parts by weight of chloroprene rubber (CR), 10 parts by weight of TPMT, 0.01 parts by weight of morpholine (6) (shown in Table 1), and An adhesive composition was obtained by blending 1 part by weight of TCIA.

(Example 7) 40 parts by weight of chloroprene rubber (CR), 10 parts by weight of TPMT, 0.05 parts by weight of morpholine (7) (shown in Table 1), and An adhesive composition was obtained by blending 1 part by weight of TCIA.

(Example 8) 40 parts by weight of chloroprene rubber (CR), 10 parts by weight of TIPP, 0.01 part by weight of morpholine (1), and 0.01 part by weight of morpholine (6) to 60 parts by weight of polyester urethane (2). (shown in Table 1), 1 part by weight of TCIA, and 20 parts by weight of Tamanol 803 to obtain an adhesive composition.

(Example 9) 40 parts by weight of chloroprene rubber (CR), 10 parts by weight of TIPP, 0.01 part by weight of morpholine (2), and 0.01 part by weight of morpholine (7) to 60 parts by weight of polyester urethane (2). (shown in Table 1), 1 part by weight of TCIA, and 10 parts by weight of Tamanol 340 to obtain an adhesive composition.

Next, in order to examine the adhesive strength of the adhesive composition thus obtained, the following moisture peel test was conducted. The test piece used for this moisture peeling test was 2
The adhesive composition was applied to a bonding area of 25 x 25 mm on a test piece of 5x polyethylene foam, and
After heating with OC for 2 minutes to evaporate the solvent, 5 kg/
cm2 load and the resulting test piece was heated at 50 OC in 98% relative humidity for 20 min.
The film was left to stand for 0 hours, and then pulled at a tension speed of 50 mm/min to measure the moisture resistance peel strength. The results are shown in Table-2.

Comparative Examples 1 to 3 were obtained using the following formulations. (Comparative Example 1) Adhesive composition obtained only from the polyester urethane (■).

(Comparative Example 2) Chloroprene rubber (CR) 1
An adhesive composition obtained by blending 00 parts by weight with 50 parts by weight of MDI and 1 part by weight of TCIA.

(Comparative Example 3) An adhesive composition obtained by blending 40 parts by weight of chloroprene rubber (CR) and 10 parts by weight of MDI with 60 parts by weight of polyester urethane.

As is clear from Table 2, isocyanate
It can be seen that an adhesive composition containing a polyester urethane having a group, chloroprene rubber, a polyisocyanate, and a halogenating agent has a peel strength so high that a foam 5 times that of polyethylene as an adherend bursts.

As is clear from Table 2, isocyanate
It can be seen that an adhesive composition containing a polyester urethane having a group, chloroprene rubber, a polyisocyanate, and a halogenating agent has a peel strength so high that a foam 5 times that of polyethylene as an adherend bursts.

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 also By halogenating the polyester-based urethane, the intermolecular force between both is increased, and the peel strength is improved by the flexible and elastic chloroprene rubber. This is thought to be due to the synergistic effect with the base to further improve the adhesive strength.

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

[0034]

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

[0035]

[Chemical formula 1]

[0035]

[0036]

[0037]

[0038]

Claims (1)

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