JPH0613622B2 - Hot melt composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel hot melt composition, and more specifically, to a hydride of a resin obtained by copolymerizing a cyclopentadiene-based monomer and isobrene by a specific method. The present invention relates to a novel hot-melt composition containing, as a tackifier, excellent in cold resistance.

Conventional technology Hot-melt compositions do not contain organic solvents in their composition, which is preferable from the viewpoint of industrial hygiene, and because the bonding is completed in an extremely short time, the speed of the bonding process can be easily realized. It is widely used industrially in bonding metals, plastics, etc.

As the baie polymer of such hot melt composition, polyethylene, ethylene-vinyl acetate copolymer,
Thermoplastic polymer compounds such as ethylene-ethyl acrylate copolymer, atactic polypropylene, polyamide, polyester, styrene-butadiene block copolymer are used, and among them, the ethylene-based polymer is adhesive, rigid and flexible. It has excellent physical properties such as heat resistance, flexibility, cold resistance, and hot melt fluidity, and is inexpensive, so it is particularly preferred.

Further, the hot melt composition contains a tackifier in order to improve the adhesiveness and workability of the base polymer,
As the tackifier, various petroleum hydrocarbon resins have been developed so far.

In particular, the hot melt composition is desired to have the smallest possible change in physical properties due to heating, and therefore, as the tackifier, a hydrogenated hydrocarbon resin having excellent thermal stability, for example,
Hydrogenated aromatic hydrocarbon resins or hydrogenated cyclopentadiene resins have been used as prizes.

However, conventional hydrogenated hydrocarbon resins have a drawback that they are not always sufficiently compatible with an olefin polymer such as an ethylene-vinyl acetate copolymer, and have poor cold resistance and flexibility.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The inventors of the present invention have made intensive studies to improve such drawbacks of a hot melt composition using a hydrogenated hydrocarbon resin as a tackifier. It was found that by hydrogenating a hydrocarbon resin obtained by thermally polymerizing a body mixture, a hydrogenated hydrocarbon resin having a small content of high molecular weight polymer can be obtained, and blending this with an ethylene copolymer It was found that a hot melt composition excellent in cold resistance can be obtained by the above, and thus the present invention was completed.

Means for Solving the Problems Thus, according to the present invention, a hydride of a (A) 40-85% by weight of cyclopentadiene-based monomer and 15-60% by weight of isoprene, which is a hydride of a thermopolymerization resin, has a softening point. 60-1
50 ° C., a bromine number of 10 or less, a polystyrene-converted molecular weight of 5000 or more and a hydrogen content hydrocarbon resin of 5 to 300 parts by weight and a polymer content of 2% by weight or less, and (B) an ethylene-based polymer 100 parts by weight. There is provided a hot melt composition comprising:

Hereinafter, the components of the present invention will be described in detail.

(Hydrogenated Hydrocarbon Resin) In the thermopolymerization resin of the present invention, cyclopentadiene-based monomer and isoprene are used as a monomer mixture. Cyclopentadiene-based monomers include lower alkyl-substituted cyclopentadiene such as methylcyclopentadiene and ethylcyclopentadiene, as well as cyclopentadiene or its alkyl-substituted dimers, trimers, and co-dimers. Diels Alder adjuncts are included. The isoprene used in the present invention is
It can also be used in the form of a co-dimer with cyclopentadiene or its alkyl-substituted form. Of course, in addition to cyclopentadiene or its alkyl-substituted product, a copolymerizable monomer such as indene, methylindene, coumarone, and styrene may coexist in a range that does not substantially impair the effects of the present invention. But instead of isoprene,
According to the present invention, a hot melt composition having excellent cold resistance can be obtained even if other chain conjugated dienes such as 1,3-pentadiene and 1,3-butadiene are used, depending on the hydrogenated hydrocarbon resin obtained from them. Can not achieve the purpose of.

In the present invention, a resin obtained by heat-polymerizing a monomer mixture consisting of a cyclopentadiene-based monomer and isoprene in the absence of a radical initiator at 240 to 300 ° C, preferably 250 to 280 ° C is used. . At this time, it is preferable to use a heat-polymerized resin obtained by continuously heat-polymerizing the monomer mixture, and the content of the polymer having a polystyrene reduced molecular weight of 5,000 or more is 2 wt% or less, preferably 1 or less depending on the batch type polymerization. It is difficult to obtain a resin of less than or equal to wt%.

The small hydrogen hydrocarbon resin of the present invention is produced by a known method, for example, using a catalyst such as nickel, palladium, cobalt, platinum, and rhodium in the presence or absence of a diluent of 150 to 300. It can be obtained by hydrogenation according to the method of hydrogenation at a temperature of ° C and has a bromination of 10 or less, a Gardner color of 1 or less and a softening point of 60-150 ° C.

The ratio of the cyclopentadiene-based monomer in the monomer mixture is in the range of 40 to 85% by weight, preferably 50 to 80% by weight, and when this ratio is less than 40% by weight, the resin yield is significantly high. It is not preferable because the amount is lowered and only a semi-solid or oily polymer is obtained. on the other hand,
If this ratio exceeds 85% by weight, it becomes difficult to control the reaction, and even when the reaction is carried out by diluting with a solvent, the softening point of the resin remarkably rises, and the hot melt composition obtained by using the hydride thereof. Cannot exhibit sufficient cold resistance.

The ratio of isoprene in the monomer mixture is in the range of 15 to 60% by weight, preferably 20 to 50% by weight, and when this ratio is less than 15% by weight, a high molecular weight polymer having a polystyrene equivalent molecular weight of 5000 or more is used. It is difficult to obtain a resin having a content of 2% by weight or less, preferably 1% by weight or less. On the other hand, when this ratio exceeds 60% by weight, the yield of the resin is significantly reduced and It is not preferable because it significantly lowers the softening point.

The hydrogenated hydrocarbon resin as the component (A) in the present invention has a molecular weight distribution in which the molecular weight converted to polystyrene is 50.
The content of the high molecular weight polymer of 00 or more is 2% by polymerization or less, but in order to further improve the compatibility with the ethylene polymer as the component (B) and the cold resistance of the hot melt composition, It is particularly preferable that the content of the high molecular weight polymer is 1% by weight or less.

(Ethylene-Based Polymer) The ethylene-based polymer which is another basic component of the composition of the present invention is an ethylene homopolymer or a copolymer containing ethylene as a main component, and a copolymerization-constituting monomer unit. Specific examples of the body include vinyl acetate, vinyl propionate, ethyl acrylate, butyl acrylate, methyl methacrylate,
Examples thereof include unsaturated acid esters such as ethyl methacrylate and unsaturated acids such as acrylic acid and methacrylic acid.

Among such ethylene polymers, ethylenic copolymers are preferable, and particularly unsaturated ester content of 10 to 50% by weight.
Therefore, an ethylene-unsaturated ester copolymer having a melt index of 0.5 to 2500 is advantageous from the viewpoint of performance when used as a hot melt composition.

(Blending ratio) The blending ratio of the ethylene polymer and the hydrogenated hydrocarbon resin depends on the desired application field such as adhesive, coating agent, sealing agent, etc. Although not always uniform, hydrogenated hydrocarbon resin 5 is generally added to 100 parts by weight of ethylene polymer.
To 300 parts by weight, preferably 50 to 200 parts by weight.

In addition, in the present invention, in addition to the ethylene-based polymer and the hydrocarbon resin, other base polymers and tackifiers can be used in combination within a range that does not substantially impair the effects of the present invention. Waxes such as paraffin wax, microcrystalline wax, polyethylene wax and the like, which are usually used in the production, plasticizers, antioxidants, fillers and the like may be added. When wax is used, it is generally 5 to 500 parts by weight based on 100 parts by weight of the ethylene polymer.

EXAMPLES The present invention will be described more specifically with reference to examples. In addition, parts and% in Examples, Comparative Examples and Reference Examples are based on weight unless otherwise specified.

Reference Example 1 An autoclave equipped with a stirrer was used at a temperature of 260 ° C. and a pressure of 1
It is maintained at 0 kg / cm ² G and the average residence time is 4 hours.
The raw materials shown in the table are continuously circulated, or the raw materials are charged in the same autoclave and reacted at a temperature of 260 ° C. for 4 hours, and then unreacted monomer, low polymer and reaction solvent are distilled off to distill A yellow transparent hydrocarbon resin was obtained. The softening point of the obtained resin was measured according to the ring and ball method specified in JIS K-2531, and the hue was measured according to JIS K-5.
The bromine number was measured by the Gardner chromaticity specified by 400, and the bromine number was measured by the titration method specified by JIS K-2543. The results are shown in Table 1 together with the resin yield.

100 parts of the hydrocarbon resin thus obtained, 100 parts of cyclohexane and a hydrogenation catalyst (stabilized nickel N-
113M; manufactured by JGC Chemical Co., Ltd.) 3 parts were charged into an autoclave, and hydrogenation reaction was carried out at a hydrogen pressure of 60 kg / cm ² G, a reaction temperature of 200 ° C. and a reaction time of 3 hours. To obtain a hydrogenated hydrocarbon resin. The properties of this resin were measured by a predetermined method, and the results are shown in Table 2.

The weight average molecular weight of the resin and the ratio of the polymer having a molecular weight of 5000 or more are determined by high performance liquid chromatography (H
It was calculated from a molecular weight distribution curve measured using LC-802A, manufactured by Toyo Algata Co., Ltd., based on a calibration curve previously obtained from the analysis results of standard polystyrene of known molecular weight. For the measurement, a column G-40 packed with polystyrene gel was used.
0H and G-2000H in combination, column temperature 4
0 ° C, carrier (tetrahydrofuran) flow rate 1.3 ml
The measurement was performed under the condition of / min.

In addition to the results in Table 2, hydrogenated hydrocarbon resin A for reference
The molecular weight distributions of H and DH are shown in FIG.

Example 1 In order to investigate the compatibility of the hydrogenated hydrocarbon resin obtained in Reference Example 1 with an ethylene-vinyl acetate copolymer and paraffin wax, an ethylene-vinyl acetate copolymer (vinyl acetate content 28%, melt・ Index 150g / 10
Min., 100 parts of Mitsui DuPont Polychemical Co., Ltd.), 50 parts of paraffin wax (melting point 145 ° F.) and 100 parts of each hydrogenated hydrocarbon resin were prepared.
The cloud point of each formulation was measured according to the method specified in IS K-2266. The results are shown in Table 3.

The compositions of the control examples have high cloud points, and the compatibility between the resin and the ethylene-vinyl acetate copolymer is insufficient, whereas the compositions of the examples of the present invention show excellent compatibility. Recognize.

Example 2 100 parts of ethylene-vinyl acetate copolymer (vinyl acetate content 28%, melt index 150), 50 parts of microcrystalline wax (melting point 173 ° F) and 100 parts of hydrogenated hydrocarbon resin are melted at 1800 ° C. After mixing and applying the mixture to an aluminum plate having a thickness of 0.1 mm to a thickness of 0.2 mm, another aluminum plate is overlaid and sealed for 2 seconds under the conditions of a pressure of 1.0 kg / cm ² and a temperature of 140 ° C. Fused to make a laminated sample. This sample is 25 mm
Cut into strips of width to make test pieces, 10 ℃, 20
The test piece was pulled at a rate of 200 mm / min at each temperature of 30 ° C., 30 ° C., and 40 ° C., and the adhesive force by the 90 ° peeling method was measured.

The results are shown in Table 4.

The compositions of the control examples all have low adhesive strength as a whole, and particularly the adhesive strength is extremely low at low temperatures, whereas the compositions of the present invention have high adhesive strength as a whole, and particularly excellent adhesive strength even at low temperatures. Can be seen. In other words, it can be seen that the hot melt composition obtained according to the present invention has excellent cold resistance.

EFFECTS OF THE INVENTION The hot melt composition obtained by the present invention has excellent hue and thermal safety, and exhibits excellent adhesive strength even at low temperatures as compared with the prior art. That is, it exhibits excellent cold resistance.

[Brief description of drawings]

FIG. 1 is a diagram showing the molecular weight distribution of hydrogenated hydrocarbon resin. AH ... Hydrogenated hydrocarbon resin used in the present invention DH ... Controlled hydrogenated hydrocarbon resin

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location C09D 145/00 PGM 7921-4J 147/00 PGN 8218-4J C09J 123/04 JBW 7107-4J 145 / 00 JDG 7921-4J 147/00 JDL 8218-4J C09K 3/10 Z

Claims (2)

[Claims] 1. A cyclopentadiene-based monomer (A) 40-
It is a hydride of a thermopolymerized resin of 85% by weight and 15-60% by weight of isoprene, having a softening point of 60 to 150 ° C., a bromine number of 10 or less, and a molecular weight converted to polystyrene of 5000.
A hot melt composition comprising 5 to 300 parts by weight of a hydrogenated hydrocarbon resin having a polymer content of 2% by weight or less and 100 parts by weight of (B) an ethylene polymer. 2. The hot melt composition according to claim 1, wherein the hydrogenated hydrocarbon resin has a polymer content of 5,000 or more in terms of polystyrene and a polymer content of 1% by weight or less.