Adhesive composition

Abstract

The present invention provides a hot-melt adhesive having a sufficiently long usable time and exhibiting good strength and good heat resistance. The present invention relates to a hot-melt adhesive composition comprising a hydrocarbon cyclic polymer (A), an α-olefin polymer (C), and a tackifying resin (D).

Claims

1. A hot-melt adhesive composition comprising a mixture of a hydrocarbon cyclic polymer (A) with a linear polymer (B) formed from the same monomer as the monomer constituting the hydrocarbon cyclic polymer (A); an α-olefin polymer (C); and a tackifying resin (D), wherein the mixture of the hydrocarbon cyclic polymer (A) and the linear polymer (B) has a melting point of 30 to 160° C, wherein the α-olefin polymer (C) is a mixture of a low melt viscosity α-olefin polymer and a low MFR α-olefin polymer, wherein the low melt viscosity a-olefin polymer has a melt viscosity at 190° C. measured by using a cone-plate rotational viscometer at a shear rate of 4.3 sec.sup.−1 of 150,000 mPa.Math.s or lower, and the low MFR α-olefin polymer has a melt flow rate measured at 230° C. and a load of 2.16 kg according to ASTM D1238 of 20 g/10 minutes or lower.

2. The hot-melt adhesive composition according to claim 1, wherein the hydrocarbon cyclic polymer (A) has a weight-average molecular weight of 200 to 3,000.

3. The hot-melt adhesive composition according to claim 2, wherein the content of the hydrocarbon cyclic polymer (A) is within the range of 0.02 to 5% by weight, based on the total weight of the composition.

4. The hot-melt adhesive composition according to claim 1, wherein the hydrocarbon cyclic polymer (A) is a cyclic trans-polyoctenemer.

5. The hot-melt adhesive composition according to claim 1, wherein the mixture of the hydrocarbon cyclic polymer (A) and the linear polymer (B) has a weight-average molecular weight of 10,000 to 500,000.

6. The hot-melt adhesive composition according to claim 1, wherein the α-olefin polymer (C) is at least one selected from the group consisting of a homopolymer having an α-olefin unit, a copolymer having an α-olefin unit, and a mixture thereof.

7. The hot-melt adhesive composition according to claim 1 comprising 2 to 20% by weight of the hydrocarbon cyclic polymer (A), 30 to 70% by weight of the α-olefin polymer (C), and 30 to 50% by weight of the tackifying resin (D).

8. The hot-melt adhesive composition according to claim 1, wherein the hot-melt adhesive composition has a viscosity of 10,000 mPa.Math.s to 200,000 mPa.Math.s at a temperature of 140 to 180° C. that is a material temperature during the application of the hot-melt adhesive composition.

9. The hot-melt adhesive composition according to claim 1, further comprising an adhesion improver.

10. The hot-melt adhesive composition according to claim 1, wherein the low melt viscosity a-olefin polymer has a melting point of 110 to 180° C. and a melt viscosity of 1,000 to 150,000 mPa.Math.s at 190° C., wherein the low MFR α-olefin polymer has a melting point of 80 to 180° C. and a melt flow rate of 4 to 20 g/10 minutes, and wherein a weight ratio of the low melt viscosity α-olefin polymer and the low MFR α-olefin polymer in the mixture is 50:50 to 90:10.

Description

EXAMPLES

(1) Examples 1 to 7 and Comparative Examples 1 to 3

(2) Components in compositions shown in Table 1 were mixed by using a mixing stirrer (double-arm kneader SV-1-1 manufactured by Moriyama

(3) Seisakusho) at 180° C. to obtain hot-melt adhesive compositions.

(4) TABLE-US-00001 TABLE 1 (g) Example 1 2 3 4 5 6 α-olefin polymer 1 *1 7 7 7 7 7 α-olefin polymer 2 *2 7 α-olefin polymer 3 *3 α-olefin polymer 4 *4 3 3 3 3 3 3 α-olefin polymer 5 *5 Hydrocarbon cyclic polymer *6 1 0.5 4 1 1 1 Hydrocarbon cyclic polymer *7 Hydrocarbon cyclic polymer *8 Tackifying resin *9 8 8 8 5 10 8 (g) Comparative Example Example 7 8 9 1 2 3 α-olefin polymer 1 *1 7 4 7 7 7 α-olefin polymer 2 *2 3 α-olefin polymer 3 *3 3 3 α-olefin polymer 4 *4 3 3 3 α-olefin polymer 5 *5 10 Hydrocarbon cyclic polymer *6 1 1 1 Hydrocarbon cyclic polymer *7 1 Hydrocarbon cyclic polymer *8 1 Tackifying resin *9 8 8 8 *1 VESTOPLAST (registered trademark) 888 (Evonic, ethylene-propylene-1-butene copolymer, melting point: 160° C., melt viscosity: 120,000 mPa .Math. s (190° C.), weight-average molecular weight: 104,000) *2 VESTOPLAST (registered trademark) EP807 (Evonic, ethylene-propylene-1-butene copolymer, melting point: 161° C., melt viscosity: 7,000 mPa .Math. s (190° C.), weight-average molecular weight: 60000) *3 TAFMER (registered trademark) XM5080 (manufactured by Mitsui Chemicals, Inc., propylene-1-butene copolymer, melting point: 160° C., MFR: 4.0 g/10 minutes (230° C.)) *4 TAFMER (registered trademark) PN0040 (manufactured by Mitsui Chemicals, Inc., propylene-1-butene copolymer, melting point: 160° C., MFR: 4.0 g/10 minutes (230° C.)) *5 TAFMER (registered trademark) DF110 (manufactured by Mitsui Chemicals, Inc., ethylene-propylene copolymer, melting point: 94° C., MFR: 2.2 g/10 minutes (230° C.)) *6 VESTENAMER (registered trademark) 8012 (Evonic, trans-polyoctenemer, ratio of trans double bond/cis double bond: 80/20, cyclic polymer content: 25% by weight, melting point: 54° C., glass transition temperature: −65° C., crystallinity: 27%, weight-average molecular weight: 100,000) *7 cyclooctene polymer (cyclic and linear mixture), ratio of trans double bond/cis double bond: 80/20, low molecular weight (200-3000) cyclic-structure oligomer content: 4.8% by weight, melting point: 56° C., glass transition temperature: −65° C., weight-average molecular weight: 80,000) *8 cyclooctene polymer (cyclic and linear mixture), ratio of trans double bond/cis double bond: 80/20, low molecular weight (200-3000) cyclic-structure oligomer content: 10% by weight, melting point: 53° C., glass transition temperature: −65° C., weight-average molecular weight: 90,000) *9 ARKON (registered trademark) P125 (manufactured by Yasuhara Chemical Co. Ltd., hydrogenated terpene resin, softening point: 125° C.)

(5) [Heat-Resistant Creep Test]

(6) After the hot-melt adhesives obtained in Examples 1 to 7 and Comparative Examples 1 to 3 were applied to a surface of a fabric with urethane foam (urethane foam thickness: 2 mm.sup.t) at 170 ° C. by using a roll coater, a polypropylene substrate (Kobe Poly-Sheet PP-N-BN manufactured by Shin-Kobe Electric Machinery Co., Ltd.) was affixed in open time of 10 seconds or 45 seconds. Subsequently, the affixed substrate was pressed at 0.05 Mpa for 5 seconds by using a hydraulic press machine. After curing at 20 ° C. and 65% RH for 24 hours, a load of 100 g was applied at 80° C. for 24 hours.

(7) Subsequently, a peeling distance was measured. The results are shown in Table 2.

(8) [Melt Viscosity]

(9) The melt viscosities of the hot-melt adhesive compositions obtained in Examples 1 to 7 and Comparative Examples 1 to 3 were measured by using a cone-plate rotational viscometer at a temperature of 150 to 180 ° C. and a shear rate of 4.3 sec.sup.−1. The results are shown in Table 2.

(10) TABLE-US-00002 TABLE 2 Example 1 2 3 4 5 6 Heat- Open time: 0 0 0 0 0 2 mm Resistant 10 seconds BAF Creep Open time: 1 mm 1 mm 1 mm 1 mm 1 mm 2 mm 45 seconds BAF BAF BAF BAF BAF BAF Melt viscosity [mPa .Math. s] 10 × 10.sup.4 11 × 10.sup.4 9.5 × 10.sup.4 15 × 10.sup.4 7 × 10.sup.4 8 × 10.sup.4 Example Comparative Example 7 8 9 1 2 3 Heat- Open time: 0 0 0 2 mm not not Resistant 10 seconds BAF bonded bonded Creep Open time: 1 mm 1 mm 1 mm fallen not not 45 seconds BAF BAF BAF BAF bonded bonded Melt viscosity [mPa .Math. s] 8 × 10.sup.4 9 × 10.sup.4 9.5 × 10.sup.4 11 × 10.sup.4 30 × 10.sup.4 25 × 10.sup.4 BAF: Interfacial failure from base material side

(11) As is apparent from the results shown in Table 2, the hot-melt adhesive composition of the present invention has a sufficient adhesion even when the open time is 45 seconds in the heat-resistant creep test. Therefore, it is understood that the hot-melt adhesive composition of the present invention has a sufficient usable time, and good heat resistance and good strength.