JPH01278591A - Adhesive composition - Google Patents

Abstract

PURPOSE:To obtain the title composition capable of firmly bonding a polyolefin based material without requiring any pretreatment by blending an urethane polymer with a polyol having low molecular weight, halogenating agent and solvent at a specific ratio. CONSTITUTION:The aimed composition obtained by blending (A) 100pts.wt. urethane prepolymer having terminal isocyanate group and obtained from polyol and polyisocyanate with (B) low-molecular weight polyol used at an amount satisfying 0.6-1.4:1 molar ratio of hydroxyl group (-OH) thereof: isocyanate group (-NCO) of prepolymer, (C) 0.002-20pts.wt. halogenating agent, preferably consisting of alkylhypohalite, hypohalogenous acid salt or a compound having -CONX- bond in a molecule and (D) a solvent such as n-hexane, toluene, acetone, tetrahydrofuran or ethyl acetate.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an adhesive composition used for difficult-to-adhere polyolefin materials, rubber products, and synthetic resin products used as automobile parts, for example. .

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

In addition, polyolefin materials such as ethylene-propylene-diene copolymer (EPDM), ethylene-propylene copolymer (EPT), polypropylene (PP), polyethylene (PE), or combinations of these with other synthetic resins and rubbers are also available. Gluing is being done.

[Problem to be Solved by the Invention 1] In the conventional bonding method described above, pretreatment such as primer treatment or corona discharge treatment is required in advance when bonding polyolefin materials, and the bonding strength of the obtained bonded body is also low. there were.

Another problem is that the adhesive strength between polyolefin materials or between them and other synthetic resins or rubbers is low.

Furthermore, there was a problem in that the coating film of the adhesive composition had poor abrasion resistance.

The purpose of the present invention is to solve the above-mentioned conventional problems and to provide an adhesive composition that can be pretreated (adhered to polyolefin feed that is difficult to adhere to) and has a high adhesive strength. The purpose of the present invention is to provide an adhesive composition having excellent abrasion resistance in one coat.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the adhesive composition has a low molecular weight based on 100 parts by weight of a urethane prepolymer having one or more terminal isocyanate groups consisting of a polyol and a polyisocyanate. The polyol has a hydro-1-syl group (-〇to■) = an isocyanate group of the prepolymer (-
The molar ratio of NCO) is O16~], 4; 1,
One step was adopted in which 0.002 to 20 parts by weight of a halosaponizing agent and a solvent were blended.

In addition, urethane prepolymer 1 having terminal isocyanate 1-groups consisting of polyol and polyisocyanate 1-
00 parts by weight, the low molecular weight polyol is added to its hydroxyl group (-01-1): isocyanate I of the prepolymer.
・The molar ratio of groups (-NCO) is 0°6 to 1. ．． 11, an adhesive composition containing 0.002 to 20 parts by weight of a halosaponizing agent, 10 parts by weight or more of silicone oil, and a solvent is also suitable.

[Detailed explanation of the means] First, the above urethane prepolymer will be described.

The above-mentioned polyols include polyoxypropylene glycol, a compound obtained by adding propylene oxide to glycerin, a compound obtained by adding propylene oxide to sucrose, a compound obtained by adding propylene oxide of trimethylolpropane, and a compound obtained by adding propylene oxide of trimethylolpropane, propylene of pentaerythrol. Compounds containing (d) oxide are examples.

1) A compound having a plurality of isocyanate groups, such as aromatic polyisocyanate such as tolylene diisocyanate (TDI), 1.5-
Naphthalene diisocyanate (NDI), xylylene diisocyanate (XDl), 4.4'-diphenylmethane diisocyanate (MDI), 4.4', 4''-
1-Riphenylmectun triisocyanate (TPMI)
, isophoronecyisocyanate 1-(IPDI), etc., 4,4'-methylenebis(
Examples include cyclohexyl isocyanate) (H-MDI) hexahydroxylylene diisocyanate, aliphatic polyisocyanate-1, and 136-hexamethylene diisocyanate.

The urethane prepolymer is synthesized by appropriately selecting the above polyol, polyisocyanate, and the solvent described below, and heating them in dry nitrogen gas at 50 to 130°C for 160 to 360 minutes.
11) It is carried out by reacting -U-.

The low molecular weight polyols include diols such as ethylene glycol, propylene glycol, bucundiol, bentanediol, hexanesiol, hepcundiol, octanediol, diethylene glycol, triethylene glycol, dithioglycol, dipropylene glycol, neobutyl glycol, 2-ethyl-2
-n-butyl-1,3-propanediol, 2.2.4
Other examples include triethanolamine, glycerin, and trimethylolpropane.

The blending ratio of this low molecular weight polyol is such that the molar ratio of the hydroxyl group (-OH) of the low molecular weight polyol to the isocyanate group (-NCO) of the urethane prepolymer is from 0.6 to
The amount is 1.4:1.

If the blending ratio deviates from this range, the wear resistance will deteriorate.

Examples of the halogenating agent include L-butylhypochloride (t-BHC) as the alkylhypohalide.
, sodium hypochlorite and potassium hypochlorite as hypohalokenate salts, N-solomosaximide (NBSI), diisocyanuric chloride as a compound having a -CONX- bond (x is a halokene atom) in the molecule Acid (TCI△)
, isocyanuric acid dichloride (DiCIA), antimony pentafluoride, a mixed solution consisting of sulfur fluoride and bromine, etc. Among these, alkyl hypohalide, hypohalous ar:I citrate or molecular Compounds having -CONX- bonds are preferred.

The distribution ratio of this halogenating agent is in the range of 0.002 to 20 parts by weight based on 100 parts by weight of the urethane prepolymer. If the blending ratio is less than 0.002 parts by weight, the degree of haloleanization is small and the strength of the adhesive composition is low, and if it exceeds 20 parts by weight, the stability of the adhesive composition deteriorates.

Examples of the above-mentioned solvents include n-hexane, n-heptane, n-octane as aliphatic hydrocarbons, cyclohexane, cyclooctane as alicyclic hydrocarbons, Hensen, ethyl Hensen, I-luene, and xylene as aromatic hydrocarbons. , acetone, methyl ethyl ketone, ethyl propyl ketone, methyl butyl ketone as ketones, tetrahydrofuran as ethers, methyl acetate, ethyl acetate, isopropyl acetate as acetic esters, methylene chloride, 1,1゜1-trichlor as halolinated hydrocarbons Examples include ethane, trichlorethylene, dimethylsulfogide (IDMsO), dimethylformamide (DMF), and the like.

The blending ratio of this solvent is 1 in 100 parts by weight of the adhesive composition.
The amount may range from 0 to 90 parts by weight. If the same proportion is less than 10 parts by weight, the solid content will be relatively high and the viscosity of the adhesive composition will increase, making application work difficult and, in turn, likely to lead to a decrease in adhesive strength; if it exceeds 90 parts by weight, On the other hand, as the solid content decreases, the film thickness of the adhesive composition becomes thinner (
Examples of the silicone oils that tend to reduce adhesive strength include dimethyl silicone oil, methyl chloride silicone oil, methylhydrogen silicone oil, and methylphenyl silicone oil.

The blending ratio of this silicone oil is 10 parts by weight or more per 100 parts by weight of the urethane prepolymer. If the blending ratio is less than 10 parts by weight, no improvement in wear resistance is observed.

(1) By employing the above-mentioned means, by applying these adhesive compositions to, for example, polyolefin-based materials that are difficult to adhere to, the polyolefin-based materials can be firmly adhesively fixed.

Furthermore, the adhesive composition containing silicone oil lowers the frictional resistance of the coating film surface, thereby increasing the abrasion resistance of the coating film.

[Examples 1 to 6 and Comparative Examples 1 and 2] Examples embodying the present invention will be described below in comparison with comparative examples.

First, the following three types (A, B, and C) were prepared as urethane prepolymers in the adhesive composition.

(Urethane prepolymer A) Glycerin propylene oxazine i adduct (approximately 3.000 molecules between molecules) 44. ．． 4 parts, triethanolamine],
, 40 parts of 4,4-diphenylmethane diisocyanate, and 17 parts of trichloroethylene were reacted in dry nitrogen gas at 80°C for 3 hours to obtain urethane prepolymer A.

(Urethane prepolymer B) Propylene oxide adduct of glycerin (approximately 3
．． 000) 44.4 parts, glycerin 0°272 parts, 4,
1.40 parts of 4-diphenylmethane isocyanate and 35 parts of trichlorethylene were mixed at 80°C in dry nitrogen gas.
A time reaction was carried out to obtain urethane prepolymer B.

(Urethane prepolymer C) Propylene oxide adduct of glycerin (approximately 2
,000)4.4. ．． 4 parts, 0 trimethylolpropane
．． Urethane prepolymer C was obtained by reacting 595 parts of 4,4-diphenylmethane diisocyanate, 40 parts of I.lichloroethylene in dry nitrogen gas at 80°C for 30 minutes.

Solid content of these urethane prepolymers (Ul): 100
The adhesive strength was measured using an adhesive composition containing a low molecular weight polyol (β-PO) and a halogenating agent in the types and proportions shown in Table 1 below based on the weight part. This adhesive composition has 20 parts by weight of triethylene as a solvent and 80 parts by weight of solids.

The method for preparing test pieces for measuring tensile shear strength in each Example and Comparative Example is as follows.

(1) Test piece ethylene-propylene-dientor polymer 100 parts by weight, carbon blank 70 parts by weight, mineral oil 35 parts by weight,
7 parts by weight of zinc white, 2 parts by weight of stearic acid, 2 parts by weight of vulcanization accelerator
parts by weight and 1.5 parts by weight of sulfur at 160°C.
Ethylene-propylene rubber vulcanizate cured for 0 minutes.

(2) Preparation method - After cleaning the surface of the test piece, an adhesive composition is applied according to a conventional method and dried at a temperature ranging from room temperature to 180°C. This drying temperature is preferably in the range of 80 to 150°C. If the temperature is less than 80°C, the curing time becomes long, and if it exceeds 150°C, there is a risk that the test piece or the adhesive composition may undergo thermal aging.

The measurement results of tensile shear strength (kg/cnt) are shown in Table-1.

The meanings of the abbreviations in Table-1 are as follows.

HD○: 1,6-hexane → monodiol BDO1,
,4-butanediol t-BHC: t-butylhypochloride NBSI:
N-Bromozacudiimide "1" CIA: Isocyanuric acid trichloride The numbers in parentheses in Table 1 indicate parts by weight based on 100 parts by weight of the solid content of the urethane prepolymer (UP).

As seen from Table 1 above, when the adhesive compositions of Examples 1 to 6 were used, the tensile shear strength was 20 kg/
cJ or higher, whereas in Comparative Examples 1 and 2, where the halogenating agent content exceeded 20 parts by weight, the adhesive compositions gelled.

The reason why the adhesive composition of this example shows such excellent adhesive strength is that the low molecular weight polyol acts as a curing agent, and the halogen in the halosaponizing agent binds to the adherend, which is ethylene-free and has no polar groups. This is thought to be because the intermolecular force between the two is increased by halogenating the propylene rubber vulcanizate and halogenating the urethane prepolymer in the adhesive composition.

As mentioned above, the adhesive composition of this example can easily adhere ethylene-propylene rubber vulcanizate, which is difficult to adhere, without using a primer or the like, and the adhesive strength of the obtained bonded body is Extremely large. Therefore, the adhesive composition of this example is suitable for adhering, for example, moldings and interior parts of automobiles in which polyolefin materials are used.

[Examples 7 to 12 and Comparative Examples 3 and 4] Other Examples embodying the present invention will be described below in comparison with Comparative Examples.

Low molecular weight polyol (a-P○), halogenating agent and silicone oil (SiC ) in the types and proportions shown in Table 2 below was used to evaluate the abrasion resistance. This adhesive composition contains 20 parts by weight of trichlorethylene as a solvent and 80 parts by weight of solids.

The method for preparing the test piece for measuring the amount of wear in each Example and Comparative Example is [Examples 1 to 6 and Comparative Examples 1 and 2]
The method is the same as (1) test piece and (2) preparation method described in .

In addition, the abrasion resistance test was conducted using the following method, and the wear resistance was determined by
Wear resistance was evaluated.

Testing machine: Tipper type rotary abrenosaur (manufactured by Toyo Seiki Seisakusho Co., Ltd.) Test conditions: Wearing wheel: I (-22, load: 1kg, abrasion rotation speed: 60rpm, sample usage: 1100mm x 100* [number of f abrasion dents: 1000 times abrasion) The measurement results of the amount ([/1000 times) are shown in Table 2.

Table-2 *) Example 7 was dried at 80°C for 30 minutes.

The meanings of Ryokan in Table 2 are as follows.

HDO; ], 6-hexanethiol BID0 1. ．． 4-phthanesiol t-B t-
I C: t-funarhaibokushi 1 light NBSI
・N-Promozakunoimi]・TCIΔ Ditrichlorinated isocyanuric acid Psi: Polysimethylsiloxane (viscosity approximately 10,000 C
s t) PS6: Polysimethylsiloxane (viscosity approximately 60,000C
5L) ps+, o+ polycynotylsiloxane (viscosity approximately 100,000C
st) The numbers in parentheses in Table 2 indicate parts by weight based on 100 parts by weight of the solid content of the urethane prepolymer.

As can be seen from Table 2 above, when the adhesive compositions of Examples 7 to 12 were used, the amount of wear was as small as 30 cm/1000 times or less, whereas as in Comparative Examples 3 and 4, the amount of wear was small when the adhesive compositions of Examples 7 to 12 were used. If the blending ratio exceeds 20 parts by weight, the adhesive composition will become slag.

The reason why the adhesive composition of this example shows such excellent abrasion resistance is that [in addition to the reasons described in Examples 1 to 6 and Comparative Examples 1 and 2], silicone in the adhesive composition This is thought to be because oil (S i O) reduces the frictional resistance on the surface of the coating film.

As shown in the above, the adhesive composition of this example can be easily adhered to ethylene-propylene rubber vulcanizate, which is difficult to adhere to, without using a primer or the like, and the abrasion resistance of the coating film is also improved. is extremely large.

[Effects of the Invention] The adhesive composition of the present invention exhibits excellent effects in that it can be bonded to polyolefin materials, which are particularly difficult to bond, without pretreatment and has extremely high adhesive strength.

In addition, the adhesive composition of the present invention containing silicone oil has the effect that, in addition to extremely high adhesive strength, the abrasion resistance of the coating film is extremely excellent.

Patent applicant Toyoda Gosei Co., Ltd. Agent
Patent Attorney On January Hironobu” 8

Claims (1)

[Claims] 1. Low molecular weight polyol is added to 100 parts by weight of a urethane prepolymer having a terminal isocyanate group consisting of a polyol and a polyisocyanate.
An adhesive composition comprising 0.002 to 20 parts by weight of a halogenating agent and a solvent in an amount such that the molar ratio of O) is 0.6 to 1.4:1. 2. To 100 parts by weight of a urethane prepolymer having a terminal isocyanate group consisting of a polyol and a polyisocyanate, add a low molecular weight polyol to its hydroxyl group (-OH): the isocyanate group of the prepolymer (-NC
O) in an amount such that the molar ratio is 0.6 to 1.4:1, 0.002 to 20 parts by weight of halogenating agent, and 1 part of silicone oil.
An adhesive composition containing 0 parts by weight or more and a solvent.