JPH04270744A - Polyolefinic resin composition - Google Patents

Abstract

PURPOSE:To improve printability and/or coating performance without influencing moldability, mechanical characteristics, etc., of polyolefinic resin. CONSTITUTION:A polyolefinic resin composition comprising (A) 70-199.9wt.% polyolefinic resin as a component and (B) 0.1-30wt.% (100wt.% total amount) alkylene oxide polymer selected from the group consisting of a homopolymer, a block copolymer and a random copolymer of an alkylene oxide monomer. The polyolefinic resin provided with the above-mentioned constitution has not only excellent printability and/or coating performances, but also excellent mechanical characteristics and is moldable into a filmy or sheetlike form or into arbitrary shapes.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to polyolefin resin compositions. More specifically, the present invention relates to a polyolefin resin composition that provides sheets and molded articles that can be printed or painted.

0002

[Conventional technology]

■ Background Polyolefin resins such as polyethylene and polypropylene have excellent mechanical and thermal properties and are inexpensive, so they are widely used as molded parts, sheets, and packaging materials, and will continue to be used more and more in the future. Demand is expected to increase. In particular, as a trend in recent years, there has been a strong demand for fashion and decorative properties in the use of this resin, and there are many cases in which printing or painting in particular is used to satisfy these demands. However, polyolefin resins are essentially non-polar and have poor adhesion to paints and inks, so it is currently difficult to meet the above requirements regarding paintability and printability.

[0004] Problems with conventional techniques Conventional techniques for imparting printability and paintability to polyolefin resins include surface treatment methods, primer coating methods,
Examples include a filler kneading method.

Among the above-mentioned methods, examples of surface treatment methods include sandblasting, chromic acid mixture treatment, plasma treatment, and corona discharge treatment. Among these existing surface treatment methods, in the sadblasting process, it is difficult to avoid surface opacity and contamination due to abrasive materials. In the chromic acid mixture treatment, major problems remain regarding the treatment of the treated waste liquid. Furthermore, plasma processing requires a large amount of processing equipment and has the disadvantage that continuous processing is difficult for molded products. Furthermore, corona discharge treatment has drawbacks such as being able to process only sheet-like materials and also producing through holes in thin film-like materials.

[0006] Next, in the method of imparting printability and paintability by applying a primer, a typical primer that uses chlorinated polypropylene as a main ingredient is used to further improve the compatibility between polyolefin resin and paint. However, with polyolefin resins containing few additives, sufficient effects cannot be obtained by primer treatment alone, and the primer itself has drawbacks such as being expensive.

Finally, the method of adding a filler is impractical in that it causes undesirable effects on the target resin, such as deterioration of physical properties and devitrification.

[0008]

[Problems to be Solved by the Invention] The present invention improves the drawbacks of known methods for modifying polyolefin resins.
The object of the present invention is to provide a polyolefin resin composition having improved printability or paintability. More specifically, it is an object of the present invention to solve the problems of the prior art described above and to provide a polyolefin resin that can be printed or coated without surface treatment or secondary treatment such as primer coating. An object of the present invention is to provide a composition.

[0009]

[Means to solve the problem]

[0010] Overview The inventors of the present invention have made extensive studies to solve the above problems, and have found that the surface characteristics of molded products are significantly improved by incorporating an alkylene oxide polymer into a polyolefin resin. Heading The present invention has been arrived at. That is,
The present invention uses polyolefin resin 70 as component (A).
~99.9% by weight, 0.1 to 30% by weight of an alkylene oxide polymer selected from the group consisting of homopolymers, block copolymers, or random copolymers of alkylene oxide monomers as component (B) ( A total of 100%) of the polyolefin resin composition has excellent printability or paintability. Hereinafter, various elements constituting the invention will be explained item by item.

(2) Polyolefin Resin The polyolefin resin herein refers to polyethylene resins such as low density polyethylene and high density polyethylene, and copolymer resins such as polypropylene and ethylene-propylene copolymers.

■Alkylene oxide polymer Also, the alkylene oxide polymer refers to an alkylene oxide polymer selected from the group consisting of homopolymers, block copolymers, and random copolymers of alkylene oxide monomers. Generally, alkylene oxide monomers are polymerized in the presence of an active hydrogen-containing compound as described below, but alcohols are particularly preferably used as the active hydrogen-containing compound.

Monoalcohols such as methanol and ethanol, ethylene glycol, propylene glycol, 1
, dialcohols such as 4-butanediol, polyhydric alcohols such as glycerin, trimethylolpropane, sorbitol, sucrose, polyglycerin, amines such as monoethanolamine, ethylenediamine, diethylenetriamine, 2-ethylhexylamine, hexamethylenediamine, etc. phenolic active hydrogen-containing compounds such as bisphenol A, hydroquinone, etc.

Examples of alkylene oxide monomers include ethylene oxide, propylene oxide, 1,2-epoxybutane, 1,2-epoxypentane, 1,2-epoxyhexane, 1,2-epoxyheptane, and 1,2-epoxyoptane. , 2-9 carbon atoms such as 1,2-epoxynonane
α-olefin oxide, and α-olefin oxide having 10 or more carbon atoms.
Although any olefin oxide can be used, it is particularly preferable to use ethylene oxide, propylene oxide, 1,2-epoxybutane, and α-olefin oxide having 5 to 10 carbon atoms.

[0015] During the polymerization reaction, sodium methoxide,
Basic catalysts such as sodium hydroxide, potassium hydroxide, lithium carbonate, and triethylamine, and acidic catalysts such as perchloric acid and boron trifluoride are used, but basic catalysts are preferably used. The molecular weight of the alkylene oxide polymer is preferably 500 to 20,000.

■ Blending in polyolefin resin The mixing ratio of the polyolefin resin (A) and alkylene oxide polymer (B) in the polyolefin resin composition of the present invention is 70 to 99.9% for the polyolefin resin (A).
Weight %, alkylene oxide polymer (B) 30-0.1
% by weight, preferably 95 to 99.5% by weight of the former, 5% of the latter
~0.5% by weight (total 100% by weight). If the mixing ratio of the alkylene oxide polymer is less than 0.1% by weight, the printability and coating properties of the composition cannot be improved, whereas if it is more than 30% by weight, the strength and other mechanical properties may deteriorate. There is a risk of inviting As described in the next section (2), various additives can be blended into the actual molding resin composition, regardless of the mixing ratio of the components (A) and (B).

■ Molding The polyolefin resin composition of the present invention is produced by heating an alkylene oxide polymer in a polyolefin resin using a conventionally known method such as a single or twin screw extruder, a Banbury mixer, a kneader, or a mixing roll. Obtained by mixing. During this mixing, it is also possible to add fillers such as glass fiber, talc, calcium carbon or clay, stabilizers, colorants, or clarifying agents, if necessary.

[0018] The polyolefin resin composition of the present invention is
It can be easily formed into a sheet by known methods such as inflation molding and T-die molding. Moreover, a molded article can be obtained using methods such as injection molding, extrusion molding, or blow molding that are commonly used in molding polyolefin resins.

[0019]

[Examples] Hereinafter, embodiments of the invention will be described with reference to Examples, but the examples are merely for explanation and are not intended to limit the idea of the invention.

■ Synthesis Example of Alkylene Oxide Polymer Synthesis Example 1 (Exemplary Compound 3 in Table 1) Using 90.1 g of 1,4-butanediol as a starting material and 9.6 g of potassium hydroxide as a catalyst, 1,2- 3,100 g of epoxybutane and 110 g in 51 autoclave
After reacting at ℃ for 8 hours, it was desalted and purified to have a number average molecular weight of 3.
,000 (calculated from the hydroxyl value) of a 1,2-epoxybutane polymer of 2,900 g.

Synthesis Example 2 (Illustrative Compound 8) Using 46 g of ethanol as a starting material and using potassium hydroxide as a catalyst, 2
, 2-g was reacted with 190 g of ethylene oxide in a 31 autoclave at 135°C for 2 hours, and then 1,2-
385 g of epoxyhexane was added and the reaction was further carried out at 110° C. for 8 hours. After that, desalination and purification are performed to produce ethylene oxide 1, which has a number average molecular weight of 600 (calculated from the hydroxyl value).
540 g of 2-epoxyhexane block copolymer was obtained.

Synthesis Example 3 (Illustrative Compound 20) Using 106 g of diethylene glycol as a starting material, using 9.5 g of potassium hydroxide as a catalyst, 1200 g of ethylene oxide
1,2-epoxybutane was added and the reaction was further carried out at 110°C for 6 hours. Thereafter, desalting and purification were performed to obtain 2,820 g of an ethylene oxide 1,2-epoxybutane block copolymer having a number average molecular weight of 3,000 (calculated from the hydroxyl value).

Synthesis Example 4 (Illustrative Compound 13) Using 92 g of glycerin as a starting material, 5 g of potassium hydroxide as a catalyst
was reacted with a mixture of 120 g of ethylene oxide and 1080 g of 1,2-epoxybutane at 105° C. for 8 hours in a 31 autoclave. Thereafter, the reaction mixture was desalted and purified to obtain 1,120 g of an ethylene oxide-1,2-epoxybutane random copolymer having a number average molecular weight of 1,200 (calculated from the hydroxyl value).

Various alkylene oxide compounds obtained in the same manner are listed in Table 1 below, including those described in the above synthesis examples.

[Table 1]

① Composition Production Example Next, a production example of the composition of the invention will be shown. All percentages in each example are percentages by weight.

Production Examples 1 to 10, Comparative Production Examples 1 to 5 A predetermined amount of polyolefin resin and alkylene oxide polymer (and other additives as necessary) were mixed in advance at room temperature, and a mixture made by Kurimoto Iron Works Co., Ltd. The mixture was heated and mixed at 200° C. using a twin-screw kneading extruder and extruded to obtain the polyolefin resin composition of the present invention in the form of pellets. Table 2 below shows the types and mixing ratios of the polyolefin resins and alkylene oxide polymers used. As a comparative example, a polyolefin resin not containing the alkylene oxide polymer of the present invention was also pelletized in the same manner, and the pellets are also shown in Table 2 below.

[Table 2]

■ Molding Examples 1 to 5, Comparative Molding Examples 1 and 2 The polyolefin resin compositions obtained in Composition Production Examples 1 to 5 and Comparative Production Examples 1 and 2 were processed using Toyo Seiki Co., Ltd. Labo Plastomill. extruded using T-die (extrusion temperature 200℃)
, a film with a thickness of 150 μm was obtained. The surface of these polyolefin films was evenly coated with offset ink "3D-Super Deluxe 50 Beni" manufactured by Toka Shiki Co., Ltd. using a printing suitability tester "RI-2" manufactured by Mei Seisakusho Co., Ltd. Complete drying time and setting time were measured. The results are shown in Table 3 below.

[Table 3]

Test Examples 1 to 5, Comparative Test Examples 1 to 3 Production Example 6
~10 and the polyolefin resin compositions obtained in Comparative Production Examples 3 to 5 were processed using an injection molding machine "NN2" manufactured by Niigata Tekkosho Co., Ltd.
50Highpershot 3,000" to obtain flat plates with a length of 15 cm, width of 10 cm, and thickness of 3 mm. These flat plates were spray-painted using Nippon Bee Chemical's urethane paint "Flexene 101".
Baking was performed at 125°C for 30 minutes. Next, 100 grids were carved at 2mm intervals on the painted surface of these painted flat plates with a razor blade, and cellophane tape made by Nichiban Co., Ltd. was pressed on top of the grid with fingers, and the remaining grids were removed at once. The initial adhesion of the paint was evaluated by counting the number of stitches. The results are shown in Table 4 below.

[Table 4]

As is clear from Tables 3 and 4 above,
The products of Test Examples 1 to 5, which are products of the present invention, have a significantly shorter drying time than those of Comparative Test Examples 1 to 3, and have good adhesion to the resin layer and paint layer. I understand that.

[0030]

[Effects of the Invention] As described above, according to the present invention, it is possible to print a free shape without employing complicated post-processing or expensive processing equipment for printing or painting polyolefin resin molded products. A polyolefin resin composition having excellent properties and paintability can be provided.

Claims (1)

[Claims] Claim 1: A group consisting of 70 to 99.9% by weight of a polyolefin resin as component (A) and a homopolymer, block copolymer, or random copolymer of an alkylene oxide monomer as component (B). A polyolefin resin composition having excellent printability or paintability, characterized by comprising 0.1 to 30% by weight (total 100%) of an alkylene oxide polymer selected from the following.