JPH01123844A - Heat-resistant container - Google Patents

Abstract

PURPOSE:To obtain a heat-resistant container which is excellent in heat resistance, mold release, etc., is lightweight, foldable and stackable and is useful as a packaging material for, e.g., a hot melt adhesive, by mixing a polyolefin resin with a specified filler and molding the resulting mixture. CONSTITUTION:A resin composition is obtained by mixing a polyolefin resin (A) (e.g., PP) with at least one optionally surface-treated filler selected (B) from among a powdery inorganic filler (a) of a mean particle diameter of 0.1-20mum, preferably selected from among CaCO3, talc, BaSO4 and graphite, a flaky inorganic filler (b) of an aspect ratio of 10-80, preferably mica, and a fibrous inorganic filler (c) of an average aspect ratio of 5-500 and a fiber length <=10mm, preferably, a glass fiber, in an amount to give a weight ratio of A to B of 60-90:40-10 and, optionally, a powdery, flaky or fibrous metallic filler, an organic filler and a chemical modifier (C). This composition is molded into a sheet of a thickness of 200-400mum and is molded into a heat-resistant container of any desired shape.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a novel heat-resistant container.

More specifically, the present invention has heat resistance, strength, and properties suitable for packaging materials such as hot melt adhesives and asphalt.
The present invention relates to a heat-resistant container made of a composite resin containing an inorganic filler, which has excellent features such as excellent mold releasability, is lightweight, and can be folded and stacked in multiple stages.

[Prior Art] Conventionally, packaging materials for products that are melted and solidified, such as hot melt adhesives and asphalt, have been made of containers made of metal, glass, ceramics, etc., and oil-impregnated paper. It is used. However, these packaging materials are not always satisfactory; for example, metal containers
When filled with molten materials such as hot melt adhesive or asphalt, the container becomes hot and heavy, making it difficult to work with. Glass and ceramic containers are also easy to break and are heavy. Oil-impregnated paper has drawbacks such as being easily torn and the items to be packaged easily adhering to it. Further, packaging materials made of resin are also known, but this material has a problem of being easily deformed due to insufficient heat resistance.

On the other hand, thermoplastic resins are easy to process, have excellent corrosion resistance,
In addition to being lightweight and relatively inexpensive, it has been widely used in many fields in recent years as a material for mechanical parts, precision parts, general industrial parts, furniture, daily necessities, etc., and as a structural material. .

However, thermoplastic resins are not always satisfactory in terms of heat resistance and dimensional stability. Therefore, in order to solve these problems, inorganic fillers have been added to thermoplastic resins. Various composite resin compositions are known.

[Problems to be Solved by the Invention] The present invention improves the drawbacks of packaging materials for products that are melted and solidified, such as conventional hot melt adhesives and asphalt, and improves heat resistance, strength, and mold release. The purpose of this work is to provide a heat-resistant container made of a composite resin containing an inorganic filler, which has excellent characteristics such as excellent properties such as excellent properties, such as being lightweight and capable of being stacked in multiple stages when folded.

[Means for Solving the Problems] As a result of intensive research to develop a heat-resistant container made of a composite resin containing an inorganic filler having the above-mentioned excellent characteristics, the present inventors found that a specific polyolefin resin was used. We discovered that a container made by vacuum forming, pressure forming, injection molding, etc. of a sheet made of a resin composition containing a predetermined proportion of an inorganic filler is suitable for the purpose, and based on this knowledge, we developed this book. The invention was completed.

That is, the present invention comprises (A) a polyolefin resin;
(B) Powdered inorganic filler with an average particle size of 0.1 to 20 μm, an average aspect ratio of 10 to 80, and a plate length of 1
Plate-shaped inorganic filler with a diameter of 5 mm or less and an average aspect ratio of 5
-500 and at least one type selected from fibrous inorganic fillers having a fiber length of 10 mm or less in a ratio of 60:40 to 90:10 based on weight. The present invention provides a heat-resistant container formed by molding a sheet.

Nawate The present invention will be explained in detail below.

In the heat-resistant container of the present invention, examples of the polyolefin resin used as component (A) include ethylene, propylene, butene-1,3-methylbutene-1,3-methylpentene-1,4-methylpentene-1, etc. α−
Examples include olefin homopolymers, copolymers thereof, and copolymers of these and other copolymerizable unsaturated monomers. Typical examples include high-density, medium-density, and low-density polyethylene, linear polyethylene, ultra-high molecular weight polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl agrilate copolymer, and other polyethylenes.
Examples include atactic, syndiotactic, isotactic polypropylene, polypropylenes such as propylene-ethylene block copolymers or random copolymers, and poly-4-methylpentene-1.

These polyolefin resins may be used alone or in combination of two or more.

In the heat-resistant container of the present invention, the inorganic filler used as component (B) has an average particle size of 0.1 to 20 p.
m, preferably 0.55-1 Op, more preferably 1-5 μm powder, average aspect ratio 10-1 Op.
80, and the plate-like length is 1 mm or less, and the average aspect ratio is 5 to 5o.

A fibrous material having a fiber length of 10 mm or less is used.

Examples of the powdered inorganic filler include silica, diatomaceous earth, barium ferrite, beryllium oxide, aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, calcium carbonate, magnesium carbonate, dolomite, dawsonite, calcium sulfate, and barium sulfate. , ammonium sulfate, calcium sulfite, talc, clay, calcium silicate, montmorillonite, bentonite, carbon black, graphite, molybdenum sulfide, zinc borate, barium metaborate, luciram borate, sodium borate, etc. Among them, calcium carbonate, talc, barium sulfate and graphite are particularly preferred.

Preferred examples of the plate-like inorganic filler include mica, and examples of the fibrous inorganic filler include glass fiber, carbon fiber, and poron fiber. Among the fibrous inorganic fillers, glass fibers are particularly preferred.

One type of these inorganic fillers may be used, or two or more types may be used in combination. Moreover, if the shape deviates from the above range, the object of the present invention will not be fully achieved.

In the present invention, to the extent that the purpose of the present invention is not impaired,
Powder-like, plate-like, or fibrous metal fillers or organic fillers can be blended as desired. Examples of the metallic filler include metal elements such as zinc, copper, iron, lead, aluminum, nickel, chromium, titanium, manganese, tin, platinum, tungsten, gold, magnesium, cobalt, and strontium; Oxides, stainless steel, solder, alloys such as brass, powders and granules such as metal ceramics such as silicon carbide, silicon nitride, zirconia, aluminum nitride, and titanium carbide, as well as aluminum fibers, stainless steel, and copper fibers. Examples include metal fibers such as brass fibers, nickel fibers, silicon carbide fibers, single crystal potassium titanate, other single metal fibers, alloy fibers, and metal whiskers corresponding to these fibers. One type of these metal fillers may be used, or two types may be used.
You may use combinations of more than one species. Examples of organic fillers include husk fibers such as rice husks, wood flour, cotton,
jute, paper strips, cellophane strips, aromatic polyamide fibers, cellulose fibers, nylon fibers, polyester fibers,
Examples include polypropylene fibers. One type of these organic fillers may be used, or two or more types may be used in combination.

In the present invention, the inorganic filler and the metal filler blended as desired can be used after being surface-treated with a known surface-treating agent, if desired. Examples of the surface treatment agent include silane coupling agents, titanate coupling agents, silica powder, and silicone oil. Examples include higher fatty acids, higher alcohols, and waxes. Among these, silane coupling agents, titanate coupling agents and silicone oils are preferred. These surface treating agents may be used alone or in combination of two or more.

There are no particular limitations on the silane coupling agent, and any one can be selected from conventionally known ones. Specific examples of the silane coupling agent include triethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-methacryloxyglopyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, β-(3, 4-epoxycyclohexyl)
Ethyltrimethoxysilane, N-β-(aminoethyl)
γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)γ-aminepropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxy Examples include silane, γ-chloropropyltrimethoxysilane, and the like. Among these, γ-aminopropyltriethoxysilane, N-β-
(Aminoethyl)γ-aminopropyltrimethoxysilane is preferred.

There are no particular limitations on the titanate coupling agent, and any titanate coupling agent can be selected and used from among conventionally known ones. Specific examples of the titanate coupling agent include isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, and tetraoctyl bis(ditridecyl). phosphite) titanate, tetra(
2,2-diallyloxymethyl-1-butyl)bis(di-tridecyl)phosphite titanate, bis(dioctylpyrophosphate)oxyacetate titanate, bis(dioctylpyrophosphate)ethylene titanate, inglobiltrioctanoyl titanate , isopropyl dimethacrylic isostearoyl titanate,
inglobil isostearoyldiacryl titanate,
Examples include isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, isopropyl tri(N-amidoethyl aminoethyl) titanate, dicumylphenyloxyacetate titanate, diisostearoyl ethylene titanate, and the like. Among these, isopropyl triisostearoyl titanate and isopropyl tri(N,-amidoethyl aminoethyl) titanate are preferred.

Furthermore, examples of the silicone oil include dimethyl silicone, methylphenyl silicone, polyether-modified silicone, alkyl-modified silicone, and methylhydrodiene polysiloxane, with dimethyl silicone and methylhydrodiene polysiloxane being particularly preferred.

There are no particular restrictions on the method of surface treating the filler using these surface treatment agents, and the surface treatment can be carried out by any commonly used method, but the temperature, treatment speed, etc. may be arbitrarily changed. A method in which the processing agent is sprayed onto the filler and mixed and stirred in a Henschel mixer is preferred because it allows for the following.

There is no particular restriction on the amount of treatment agent used in such surface treatment, but usually 0
．． The amount is selected within the range of 0.01 to 5 parts by weight, preferably 0.05 to 3 parts by weight, and more preferably 0.1 to 2 parts by weight. If this amount is less than 0.01 part by weight, the effect of wetting the polyolefin resin and the filler will not be sufficiently exhibited, resulting in poor molding workability, which is not preferable.

On the other hand, if the amount exceeds 5 parts by weight, the lubricating effect is too great, causing slipping, resulting in poor pellet productivity and molding workability, and excessive bleed-out of the treatment agent, which impairs the appearance, which is not preferable.

Regarding the blending ratio of the polyolefin resin as the component (A) and the inorganic filler as the component CB in the present invention,
The weight ratio of component (A) and component (B) is 60:
40 to 90:10, preferably 70:30
It is necessary to mix them in a ratio of 85:15 to 85:15. If the amount of polyolefin resin blended is less than the above range, mold releasability and strength will tend to decrease, while if it is more than the above range, heat resistance and rigidity will tend to decrease.

In the present invention, in addition to the above-mentioned components (A) and (B), a chemical modifier may be added as desired. Examples of the chemical modifier include modified polyolefin, low molecular weight polypropylene, and oxidized low molecular weight polypropylene. By blending these chemical modifiers, the compatibility between polyolefin resin and metal fillers and inorganic fillers can be improved, making it possible to obtain molded products with better mechanical properties and dimensional stability. can.

Examples of the modified polyolefin include unsaturated organic acids or derivatives thereof, such as acrylic acid, methacrylic acid, maleic acid, and itaconic acid; unsaturated organic acids such as maleic anhydride, itaconic anhydride, and citraconic anhydride; acid anhydrides, esters of unsaturated organic acids such as methyl acrylate, monomethyl maleate, acrylamide,
Amides of unsaturated organic acids such as 7-maric acid monoamide, imides of unsaturated organic acids such as itaconic acid imide, etc. are added to 100 parts by weight of ethylene or propylene polymer, usually in O.
, OS to 20 parts by weight are added and modified by a grafting method. In this modification, organic peroxides such as benzoyl peroxide, lauroyl peroxide, dicumyl peroxide, and t-butyl hydroperoxide are used to promote modified polymerization.

In addition to the above, ethylene or propylene polymers, etc., are graft-modified with unsaturated epoxides such as glycidyl acrylate, glycidyl methacrylate, vinyl glycidyl ether, allyl glycidyl ether, etc., and during such graft modification, terminal Liquid rubbers such as hydroxylated polybutadiene can also be used.

Among such modified polyolefins, those obtained by chemically modifying a polyolefin with the above-mentioned unsaturated carboxylic acid or its derivative and a liquid rubber such as terminal hydroxylated polybutadiene are particularly preferably used.

In addition, as low molecular weight polypropylene, molecular weight 2.0
Those in the range of 00 to 20.1100 are preferably used. On the other hand, oxidized low-molecular-weight polypropylene is obtained, for example, by oxidatively decomposing isotactic polypropylene with an oxidizing agent such as peroxide in the solid phase, melt phase, or solution phase, and oxygen is present in the carboxyl group in the molecule. It exists in the form of Therefore, such oxidized low molecular weight polypropylene has some carboxyl groups in the molecule. The oxidized low molecular weight polypropylene preferably has an average molecular weight in the range of 1,500 to 2G. Among these chemical modifiers, modified polyolefins are preferred. Further, in the present invention, one type of the chemical modifier may be used, or two or more types may be used in combination.

To produce the heat-resistant container of the present invention, first, the required amounts of the components (A) and (B), as well as various fillers and chemical modifiers used as desired, are melt-kneaded in accordance with a conventional method to form a composite. A resin composition is prepared by This melt-kneading can be carried out using, for example, a Henschel mixer, a single-screw or twin-screw extruder, a Banbury mixer, a roll, or other conventional methods, but in particular, a Henschel mixer, an extruder, or a Banbury mixer is used. It is preferable to do so.

At this time, various additives commonly used in resin compositions, such as lubricants, colorants, stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, plasticizers, etc., may be added as desired. be able to.

Next, the resin composition thus prepared is formed into a sheet with a thickness of about 200 to 400 μm by extrusion molding or the like, and then this sheet is formed by vacuum forming, pressure forming, etc.
The heat-resistant container of the present invention can be obtained by molding the container into a desired shape using a molding method such as injection molding. At this time, in order to improve the mold releasability, the sheet may be coated with silicone etc. and molded.
A polyethylene terephthalate film or the like of about μm size may be laminated and molded.

[Effects of the Invention] The heat-resistant container of the present invention is made of a resin composition in which a polyolefin resin is blended with an inorganic filler of a specific shape. It also has excellent features such as being foldable and stackable in multiple stages.
; have characteristics, such as hot melt adhesives and asphalt
It is suitably used as a packaging material for products that are melted and solidified to be used, such as ruts.

When using this heat-resistant container, after pouring the molten packaging material into the container and solidifying it, the surface is covered with, for example, a polyethylene terephthalate film with a thickness of about 5 μm, so that it can be easily stacked. can prevent the adhesion of

[Example] Next, the present invention will be explained in more detail with reference to Examples.
The present invention is not limited in any way by these examples.

The characteristics of the container were evaluated as follows.

(1) Heat distortion temperature According to ASTM D-648, low load (4.6 kg/
cm”).

(2) Heat deformability After pouring the melt into a container and taking it out after 3 hours, the degree of deformation of the container was observed, and the heat deformability was evaluated according to the following criteria.

O: Almost the same as the original shape Δ: The bottom partially shrinks ×: The whole shrinks significantly (3) Release properties Workability when pouring the melt into a container and taking it out after 3 hours The condition of the sheet after being taken out was checked, and the mold releasability was evaluated according to the following criteria.

○: Easily peeled off, no change in sheet condition ΔD Some contents remain, but easily removed ×: Difficult to peel off, resulting in peeling (4) Strength As shown in Figure 1, Put 9 in the solid 5,
The strength of the container when both ends were lifted was evaluated according to the following criteria.

O: No abnormality Δ: Part B is partially torn. ×: Part B or handle A is completely torn. (5) Tear strength The strength in the longitudinal direction was determined in accordance with JIS P-11116.

Moreover, the following polyolefin resin and inorganic filler were used.

(I) Polyolefin resin PP...Polypropylene (Idemitsu Petrochemical, E-100G) PE...Polyethylene (Idemitsu Petrochemical, 520B) (n) Inorganic filler talc...A: Average particle size 5 μm B: Average particle size 0.07 μm C: Average particle size 25 μm Charcoal calcium carbonate A: Average particle size 3 μm B: Average particle size 0.05 μm C: Average particle size 25 μm Mica-Il-90p mSt = 1. 8pm, aspect ratio Q/1=50 Barium sulfate...average particle size 3μm GF...Glass fiber, Q-3mm, d-13
Pms aspect ratio Q/d-231 Graphite: Average particle size 7 μm Examples 1 to 22, Comparative Examples 1 to 6 Polyolefin resin and inorganic filler were mixed in the proportions shown in Table 1 using a single screw extruder ( Made by Nakatani Kikai, NVC-
50) i: After kneading at 200 to No°C, pellets were prepared.

Next, the pellets were processed using a T-die extruder (Mitsubishi Heavy Industries Department, N
ull-90, L/D=32), 220-260°
After producing a sheet with a thickness of 300 μIn under the condition of C1350 kg/br, about 1 to 3 μl of silicon was added to this sheet.
The container shown in FIG. 2 was prepared by applying the coating to a thickness of .mu.rn and vacuum forming it. In Figure 2, II, -100
'mm, 11. = 200mm5I13= 250m
It is m.

In this container, a vinyl acetate hot melt adhesive was melted at 13,000° C., poured as it was, and cooled and solidified. Similarly, blown asphalt was melted at 160° C., poured as it was, and cooled and solidified to determine the characteristics of the container.

The evaluation results of the containers are shown in Table 1.

(Margin below)

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a method for determining the strength of a container, and FIG. 2 is a perspective view of containers manufactured in Examples and Comparative Examples. In FIG. 1, A is a handle portion, B is a connection portion between containers, and in FIG. 2, 11, Q2, and t3 represent lengths, each of which is 100 mm. 200mm, Hllmm. Representative patent attorney Naoki Fukumura, 1. Pa,・'Figure 1

Claims (1)

[Scope of Claims] 1 (A) a polyolefin resin, (B) a powdery inorganic filler with an average particle size of 0.1 to 20 μm, an average aspect ratio of 10 to 80, and a plate length of 1 mm or less and at least one selected from the group consisting of a plate-like inorganic filler and a fibrous inorganic filler having an average aspect ratio of 5 to 500 and a fiber length of 10 mm or less in a ratio of 60:40 to 90:10 based on weight. A heat-resistant container formed from a composite resin sheet containing an inorganic filler in a proportion of . 2. Claim 1 in which the powdered inorganic filler is calcium carbonate, talc, barium sulfate or graphite.
Heat-resistant container as described in section. 3. The heat-resistant container according to claim 1, wherein the plate-shaped inorganic filler is mica. 4. The heat-resistant container according to claim 1, wherein the fibrous inorganic filler is glass fiber.