JPH0721030B2 - Modified amorphous propylene-ethylene copolymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel modified amorphous propylene-ethylene copolymer, more specifically, as a modifier for various resins, adhesiveness, The present invention relates to a modified amorphous propylene-ethylene copolymer which can be used as various resins having excellent printability and dyeability.

[Problems to be Solved by Conventional Techniques and Inventions]

It has been known to improve physical and chemical properties of polyolefins by introducing a ketone group, an aldehyde group, a carboxyl group or the like into a non-polar high molecular weight polyolefin such as polyethylene or polypropylene. That is, by introducing the above-mentioned functional group into the polyolefin, the adhesiveness with the polar substance is improved, and the printability and the dyeability are remarkably improved.

In particular, an amorphous propylene-ethylene random copolymer is obtained in a small amount as a by-product when producing a random copolymer of polypropylene, but the ethylene content is
It is at most 5 mol% or less.

Amorphous propylene-ethylene block copolymer is also partially produced as a by-product during the production of polypropylene block copolymer.

Thus, by setting the monomer charge of propylene and ethylene in an appropriate range, it is possible to produce the above-mentioned amorphous propylene-ethylene random copolymer, but not as a by-product. Little is known about a method for producing an amorphous propylene-ethylene random copolymer having a propylene content of 71 to 95 mol% and an ethylene content of 5 to 29 mol% by the intended production using a supported high activity catalyst. .

The above-mentioned amorphous propylene-ethylene random copolymer is used as a raw material for an asphalt modifier or as a raw material for a hot melt adhesive combined with an adhesive, but the amorphous propylene- Since the ethylene random copolymer does not have a polar group during the molecule production, it cannot be used alone as a hot melt adhesive or the like. Therefore, the appearance of a new modified amorphous propylene-ethylene copolymer having a functional group in the molecule has been earnestly desired.

Therefore, as a method of improving the adhesiveness, various proposals have been made in the past. For example, in the case of improving the adhesiveness of polypropylene, a method of grafting a monomer composed of an unsaturated carboxylic acid or a derivative thereof onto polypropylene, etc. It has been known.

Examples of the grafting method include a method of reacting in a solution state (for example, JP-B-44-15422), a method of reacting in a slurry state (for example, JP-B-43-18144), and a method of reacting in a molten state. (For example, Japanese Examined Patent Publication No. 43-27421) and the like have been proposed. Among these, the method of reacting in the molten state has an advantage that the operation is simple because an extruder is used, but the graft ratio is usually as small as a few% or less, and the modified polymer obtained contains unreacted monomers. If there is a large amount of residual monomer, the adhesiveness is insufficient, and there is a problem in that the monomer forms bubbles when forming a sheet, film, blow molding or the like.

Therefore, a solution reprecipitation method, a solvent extraction method (for example, JP-A-54-99193) and the like have been proposed as methods for removing unreacted monomers, but a large amount of solvent or poor solvent must be used. However, there was a problem that the operation was complicated and the cost was high.

On the other hand, as a representative of low molecular weight, a liquid modified ethylene random copolymer obtained by grafting an ethylene random copolymer with an unsaturated carboxylic acid or the like is known (JP-A 61-126120). Gazette). This modified ethylene-based random copolymer has an ethylene content of 30 to 75 mol%, and α-
The olefin component is in the range of 25 to 70 mol%, and its use as a raw material for a polyamide composition has been proposed. (JP Sho
62-11766).

Further, JP-A-60-35043 discloses a method of blending an ionomer resin with a graft copolymer obtained by modifying an ethylene-α-olefin copolymer with an α, β-unsaturated carboxylic acid or a derivative thereof. However, the ethylene content in the modified graft copolymer is about 70-95.
It has a high ethylene content in mol%.

Moreover, when atactic polypropylene with a number average molecular weight of 400 to 3000 (100 mol% of propylene) is reacted with maleic anhydride, succinic anhydride groups are converted to 12 at 200 to 250 ° C for 6 hours.
Derivatives containing ~ 17% were obtained, which have been proposed for use as oil-soluble surfactants and motor oil additives (Polymer Digest 10 94 (1984)).

Further, the atactic propylene-ethylene copolymer is
It is known and generally has an ethylene content of 5 to 50% by weight, mainly composed of a heptane-soluble portion separated and by-produced by solvent extraction as an atactic portion in the process of producing a propylene-ethylene block copolymer, and trichloride. Soluble polymer part obtained by polymerizing propylene in the presence of a catalyst containing titanium and an organoaluminum compound, and then copolymerizing ethylene and propylene in the presence of a propylene polymer, and extracting this polymer with an aliphatic hydrocarbon solvent. (JP-A-57-94032), the atactic propylene-ethylene copolymer has a molecular structure in which the arrangement of propylene and ethylene is likely to be a block, and atactic as a by-product. Polymer has a large variation in quality,
It has a problem that there are many catalyst residues.

Therefore, an object of the present invention is to provide a modified amorphous propylene-ethylene copolymer which can be used as a modifier for various resins or as a resin excellent in adhesiveness, printability and dyeability. To do.

[Means and Actions for Solving the Problems]

As a result of various studies on the amorphous propylene-ethylene copolymer, the present inventors have found that the ethylene component and the number average molecular weight in the amorphous propylene-ethylene copolymer are
It has been found that the above objects can be achieved when the unsaturated carboxylic acid derivative has a graft ratio of the components within a specific range.

The present invention has been made based on the above findings, and the amorphous propylene-ethylene copolymer has 3 to 30 carbon atoms.
An amorphous propylene-ethylene copolymer obtained by graft-copolymerizing an unsaturated carboxylic acid derivative component comprising 10 unsaturated carboxylic acids, their acid anhydrides and their esters, wherein: (1) the above-mentioned amorphous propylene-ethylene; The propylene component of the copolymer is in the range of 76 to 95 mol% and the ethylene component is in the range of 5 to 24 mol%, and (2) the number average molecular weight of the above-mentioned amorphous propylene-ethylene copolymer is in the range of 3,500 to 30,000. (3) The graft ratio of the unsaturated carboxylic acid derivative component is 0.1 to 40 parts by weight based on 100 parts by weight of the amorphous propylene-ethylene copolymer. And an amorphous propylene-ethylene copolymer.

In the modified amorphous propylene-ethylene copolymer of the present invention, the content of the propylene component of the amorphous propylene-ethylene copolymer is 71 to 95%, and the content of the ethylene component is 5 to 29 mol%. It is in the range, and more preferably the content of the ethylene component is 10 to 25 mol%. Ethylene component is 5
If it is less than 29 mol%, the grafting reaction of the unsaturated carboxylic acid derivative described later is difficult, and if it exceeds 29 mol%, the viscosity of the reaction system increases. The amorphous propylene-ethylene copolymer can be produced by a random copolymerization reaction of propylene and ethylene. That is, the amorphous propylene-ethylene copolymer is produced by the objective production of highly random copolymerization of propylene and ethylene using a highly active catalyst capable of a substantially deashing process. . Then, the random copolymer can be extracted with boiling n-heptane, and the yield of the extracted soluble amorphous propylene-ethylene copolymer is usually 80% by weight or more. Examples of the highly active catalyst that can be used for the above-mentioned target production and that can be subjected to a substantially deashing process include a titanium-supported solid catalyst supported on a magnesium component. The amount of the catalyst used is preferably in the range of 1000 to 100,000 g / g-Cat. Of propylene, more preferably 1000 to 500,000 g / g-Cat. As other reaction conditions, a pressure of 1 to 80 kg / cm ² G, a reaction temperature of 10 to 100 ° C., and a reaction time of 10 to 240 minutes are preferable.

The modified amorphous propylene-ethylene copolymer of the present invention has a number average molecular weight of the amorphous propylene-ethylene copolymer in the range of 3500 to 30000, more preferably 5
It is 0000 to 10000. If the number average molecular weight is less than 3500, the properties as a polymer will not be exhibited, and if it exceeds 30,000, it is not preferable in terms of physical properties such as viscosity for use as an adhesive or the like.
The number average molecular weight can be measured by a known method such as gel permeation chromatography (GPC). The modified amorphous propylene-ethylene copolymer of the present invention comprises an unsaturated propylene-ethylene copolymer, an unsaturated carboxylic acid having 3 to 10 carbon atoms, an acid anhydride thereof and an ester thereof. The unsaturated carboxylic acid derivative component is graft-copolymerized.

The unsaturated carboxylic acid derivative component has 3 to 10 carbon atoms.
And more preferably 4-8. If the number of carbon atoms is less than 3, odor is strongly attached to the polymer, and if the number of carbon atoms exceeds 10, the graft reaction is unlikely to occur.

Thus, unsaturated carboxylic acid having 3 to 10 carbon atoms,
Examples of the unsaturated carboxylic acid derivative composed of the acid anhydride and the ester thereof include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, bicyclo (2,2,1) hept- Unsaturated carboxylic acids such as 2-ene-5,6-dicarboxylic acid, malinic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo (2,2,1) hept-2-ene-5, Unsaturated carboxylic acid anhydrides such as 6-dicarboxylic acid anhydride, methyl acrylate, methyl methacrylate, dimethyl maleate, diethyl monomethylfumarate maleate, dimethyl itaconate, diethyl citraconic acid, dimethyl tetrahydrophthalic anhydride, bicyclo Esters of unsaturated carboxylic acids such as dimethyl (2,2,1) hept-2-ene-5,6-dicarboxylate And the like. Among these, maleic acid, itaconic acid or their anhydrides are preferable. The modified amorphous propylene-ethylene copolymer of the present invention has a graft ratio of the unsaturated carboxylic acid derivative component of 0.1 to 40 with respect to 100 parts by weight of the amorphous propylene-ethylene copolymer. It is 0.5 to 20 parts by weight, more preferably 0.5 to 20 parts by weight. If it is less than 0.1 part by weight, the polarity is insufficient, and if it exceeds 40 parts by weight, it is usually difficult to obtain a product by a graft reaction.

Modified amorphous propylene in the above graft ratio
To obtain an ethylene copolymer, an unsaturated carboxylic acid,
The amount of the unsaturated carboxylic acid derivative consisting of the acid anhydride and the ester thereof is preferably 0.1 to 50 parts by weight, more preferably 0.4 to 40 parts by weight, based on 100 parts by weight of the amorphous propylene-ethylene copolymer. Is. If it is less than 0.1 parts by weight, the graft reaction rate is low, and use of more than 50 parts by weight is meaningless since the reaction rate does not increase above a certain value. When the graft reaction is carried out in a solution state, solvents such as xylene and other aromatic hydrocarbons, heptane and other aliphatic hydrocarbons, and acetone and other ketones are preferably used in order to facilitate the reaction. When using a solvent, use xylene-
It is also possible to employ a mixed solvent such as acetone. The amount of solvent used is amorphous propylene-ethylene copolymer 100
A ratio of 200 to 1000 parts is preferable with respect to parts. If the amount of solvent is too large, a large reactor will be used, and if the amount of solvent is too small, the graft reaction rate may be slow.

It is effective to disperse the unsaturated carboxylic acid derivative consisting of the unsaturated carboxylic acid, its acid anhydride and its ester in the coexistence of the solvent and the amorphous propylene-ethylene at room temperature for 30 to 60 minutes. A peroxide is usually added to such a dispersed state system in order to accelerate the graft reaction.

As the peroxide, for example, an organic peroxide is used, and one having a decomposition temperature in the range of 120 ° C. to 270 ° C. whose half-life is 1 minute is particularly preferable. There are peroxides and organic peresters, and more specifically, for example, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2, 5-di (peroxide benzoate) hexyne-3,1,4-bis (tert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-butyl peracetate, 2,5-dimethyl-2,5
-Di (tert-butylperoxy) hexane, tert-butylperbenzoate, tert-butylperphenylacetate, tert-butylperisobutyrate, tert-butylper-sec-octoate, tert-butylperpivalate, cumylperpyrate Mention may be made of barrate, tert-butyl peroxybenzoate and tert-butyl perdiethyl acetate. Among these, benzoyl peroxide,
Di-tert-butyl peroxide and tert-butyl peroxybenzoate are preferably used.

The amount of the peroxide used is, based on 100 parts of the amorphous propylene-ethylene copolymer, 0.05 to 10 parts, and 0.15 to
8 parts is preferred.

If it is 0.05 parts or less, it is difficult to sufficiently react an unsaturated carboxylic acid, an unsaturated carboxylic acid derivative consisting of its acid anhydride and its ester, and if it is 10 parts or more, the backbone of the amorphous propylene-ethylene copolymer. This is not preferable because the main chain of the polymer is cleaved and the deterioration proceeds.

The temperature of the graft reaction is preferably 115 to 200 ° C. If the reaction temperature is too low, the graft reaction becomes difficult to proceed, and if it is too high, the cleavage of the trunk polymer molecule occurs. The reaction time is 10 minutes to 8 hours, preferably 3 to 6 hours.

The peroxide may be added to the reaction system as it is or after being dissolved in an organic solvent in the total amount or divided into several times, but it may be added to an amorphous propylene-ethylene copolymer, a solvent, maleic anhydride or the like. It is desirable to add it to the system in which the test agent coexists.

After the completion of the graft reaction, a method of removing and separating the unreacted modifying agent from the modified amorphous propylene-ethylene copolymer by solvent extraction is usually adopted. For example, when maleic anhydride is used as a modifying agent, the unreacted maleic anhydride is modified with an amorphous propylene-ethylene copolymer by utilizing the property that maleic anhydride is soluble in acetone. Separate from.

Such modified amorphous propylene-ethylene copolymer can be used as a modifier for various resins or as various resins required to have excellent adhesiveness, printability and dyeability. it can.

On the other hand, the modified amorphous propylene-ethylene copolymer of the present invention is an unmodified amorphous propylene-ethylene copolymer using a special extruder such as a taper screw type kneader ruder, It is also possible to produce it by extrusion-kneading a modifier such as a peroxide and maleic anhydride or itaconic anhydride in a solvent.

In this case, the operation is simple, but the graft ratio is low.

Hereinafter, the novel modified amorphous propylene-ethylene copolymer will be specifically described with reference to examples, but the present invention is not limited to these examples.

〔Example〕

Example 1 Production of Unmodified Amorphous Propylene-Ethylene Copolymer First, a titanium-supported catalyst solid component supported on a magnesium component in an autoclave with an internal volume 2 equipped with a stirrer.
After attaching a glass ampoule enclosing 3 mg (titanium content: 5.2 wt%), the air in the autoclave was replaced with nitrogen. Then, were charged triethylaluminum 1.2 mmol of n- heptane solution 1.5ml into the autoclave, a hydrogen gas 1kg / cm ² · G, ethylene 11 kg / cm ² ·
G, 1100 ml of liquid propylene was introduced into the autoclave and shaken. Then, the contents of the autoclave were heated to 65 ° C., stirring was started to crush the glass ampoule, and propylene and ethylene were subjected to a copolymerization reaction at the same temperature for 1 hour.

After the completion of the polymerization reaction, unreacted propylene is released to give about 1
N-heptane of was introduced and stirred, and the n-heptane reaction mixture was taken out. This n-heptane reaction mixture was charged into a rotary evaporator, and n-heptane was distilled off under heating.

The production amount of the obtained copolymer was 74000 g / g-Cat.hr.

When the propylene content of this copolymer was analyzed by ¹ H-NMR, it was 84.8 mol%, and the ethylene content was 15.2 mol%.

When 5 g of this copolymer was precisely weighed and extracted with boiling n-heptane for 20 hours using a Soxhlet extractor, the amount of the extracted copolymer was 94.2% by weight.

The number average molecular weight of the obtained copolymer was measured by GPC to obtain a value of 5800. Production of modified amorphous propylene-ethylene copolymer One reactor made of glass equipped with a stirrer was used as described above. After adding 300 g of unmodified amorphous propylene-ethylene copolymer produced by the method and pressurizing in a nitrogen atmosphere of 0.2 kg / cm ² · G for 0.1 hour, the inside pressure was reduced to 1 mmHg.
After repeating the operation, the inside of the reactor is kept under a nitrogen atmosphere after the operation. Next, the contents of the reactor were heated to 160 ° C., 15 g of maleic anhydride preheated in two dropping funnels and heated to 60 ° C., and 3 g of di-tert-butyl peroxide were gradually added over 3 hours. Dropped. After dropping, the reaction is continued for another 3 hours at the same temperature, and then the reactor is kept at 180 ℃.
It was heated up to. Then, the pressure was reduced to 0.5 mmHg to remove unreacted maleic anhydride, and the reactor was kept under the reduced pressure. After removing maleic anhydride, acetone 1 was added to the reaction product and the mixture was heated to 50 ° C., and the reaction product was thoroughly washed and then separated. This operation was repeated 3 times to obtain a modified amorphous propylene-ethylene copolymer.

As a result of measuring the infrared spectrum of the modified amorphous propylene-ethylene copolymer, clear peaks due to maleic anhydride were observed at 1785 cm ^-1 and 1860 cm ^-1, and maleic anhydride was found in the copolymer. Was found to have been introduced.

Furthermore, as a result of quantitative analysis by infrared spectrum,
The grafting ratio of maleic anhydride component in the modified amorphous propylene-ethylene copolymer (weight percentage of maleic anhydride grafted to 100 parts of the copolymer) (grafting ratio) was 3.6%. It was The number average molecular weight by GPC was 5,860.

Example 2 In this example, a modified amorphous propylene-ethylene copolymer was prepared as follows.

Example 1 except that the amount of maleic anhydride charged was 30 g.
The modified amorphous propylene-ethylene copolymer was produced in the same manner as in.

The graft ratio of maleic anhydride was 6.9%.

Example 3 In this example, a modified amorphous propylene-ethylene copolymer was prepared as follows.

80 g of the unmodified amorphous propylene-ethylene copolymer produced in Example 1, 32 g of maleic anhydride, and 600 ml of xylene were added to the reactor 1 and the inside was thoroughly replaced with nitrogen. Then, the content was heated to 120 ° C., and a solution containing 8 g of benzoyl peroxide was added dropwise to 80 ml of a 1: 1 mixed solvent of acetone and xylene over 1 hour. Then, after reacting at 120 ° C. for 4 hours, 800 ml of acetone was added to the reaction product, and the reaction product was thoroughly washed to remove unreacted maleic anhydride.

Thus obtained modified amorphous propylene-
The graft ratio of maleic anhydride in the ethylene copolymer is
It was 2.62%.

Example 4 In this example, a modified amorphous propylene-ethylene copolymer was prepared as follows.

Using a taper screw type kneader ruder (manufactured by Kasamatsu Kako Kenkyusho), with respect to the unmodified propylene-ethylene copolymer manufactured in Example 1, 0.4 ph of itaconic anhydride was used.
By mixing 0.2 phr of r, tert-butyl peroxybenzoate and melt-kneading at a temperature of 173 ° C.,
The graft reaction was performed. The reaction product was obtained by repeating melting three times with hot paraxylene and then reprecipitating with acetone. The reaction product obtained by washing is
A modified amorphous propylene-ethylene copolymer was obtained by drying in a vacuum dryer at 60 ° C. for 20 hours. In the infrared spectrum of the thus-obtained amorphous propylene-ethylene copolymer, a peak attributable to itaconic anhydride was observed at 1794 cm ^-1 .

As a result of quantitative analysis by infrared spectrum, the graft ratio of itaconic anhydride in the modified amorphous propylene-ethylene copolymer was 0.15%.

Use Example 1 Next, the performance of the modified amorphous propylene-ethylene copolymer of each example obtained as described above as a hot melt adhesive was tested as follows.

The modified amorphous propylene-ethylene copolymer of Example 1 melted was applied on a commercially available PET film (Mylar sheet manufactured by Maruichi Paper Industry Co., Ltd.) having a thickness of 25 μm to a thickness of 60 μm.

A 25μ thick PET film is placed on top of this, 120 ° C, 3kg / cm
^A hot-melt adhesive was applied under a pressing condition for ² and 10 seconds to fabricate a sample of a laminated film. This laminated film was cut into a strip having a width of 25 mm and subjected to a peeling test by the T-peel method. As a result of measuring the adhesive strength of the sample under the condition of the peeling speed of 300 mm / min, the adhesive strength at 25 ° C. was 4.0 kg / 25 mm.

As a comparative example, the performance of an unmodified amorphous propylene-ethylene copolymer as a hot melt adhesive was tested. The test was conducted in the same manner as in Use Example 1 except that the unmodified amorphous propylene-ethylene copolymer obtained in Example 1 was used to measure the adhesion strength. Was 0.1.

As is clear from the above results, the modified amorphous propylene-ethylene copolymer of this example has a significantly improved adhesive strength as compared with the unmodified amorphous propylene-ethylene copolymer. You can see that

Use Examples 2 to 4 A laminated film was prepared in exactly the same manner as in Use Example 1 except that the modified amorphous propylene-ethylene copolymer used in Examples 2 to 4 was used, and the laminated film was prepared at 25 ° C. The adhesive strength was measured and the values shown in the following table were obtained.

As is clear from these results, it is understood that the adhesive strengths of Examples 2 to 4 are remarkably improved as in Example 1.

[Effects of the Invention] The modified amorphous propylene-ethylene copolymer of the present invention can be used as a modifier for various resins or as a resin excellent in adhesiveness, printability and dyeability. .

Claims (1)

[Claims] 1. An amorphous propylene-ethylene copolymer graft-copolymerized with an unsaturated carboxylic acid derivative component comprising an unsaturated carboxylic acid having 3 to 10 carbon atoms, its acid anhydride and its ester. A propylene-ethylene copolymer, wherein (1) the amorphous propylene-ethylene copolymer has a propylene content of 76 to 95 mol% and an ethylene content of 5 to 24.
(2) the number average molecular weight of the amorphous propylene-ethylene copolymer is in the range of 3500 to 30000, and (3) the graft ratio of the unsaturated carboxylic acid derivative component is in the range of A modified amorphous propylene-ethylene copolymer, characterized in that it is 0.1 to 40 parts by weight with respect to 100 parts by weight of the crystalline propylene-ethylene copolymer.