JPH02305855A - Thermoplastic resin composition and its film or sheet - Google Patents

Abstract

PURPOSE:To obtain a thermoplastic resin composition improved in stickiness during molding and improved in compatibility with another resin by mixing a thermoplastic polyurethane resin with a specified modified styrene copolymer. CONSTITUTION:A thermoplastic resin composition is obtained by mixing 40-99wt.% thermoplastic polyurethane resin (A) with 80-45wt.% maleic anhydride- modified styrene copolymer (B) (desirably of a styrene content of 80-45wt.% and maleic anhydride content of 20-55wt.%). By mixing resin A with copolymer B, a composition which is improved in film orientability and appearance (pinhole and surface roughening) without detriment to the characteristics of resin A and excelling in an ability to form a film which is not sticky during molding or film winding can be obtained. This composition is applicable to belt hoses, soles, synthetic leathers, etc.) produced by extrusion or injection molding, and particularly the obtained film has a very high practicability as waist gathers of a paper napkin or an elastic film for leg gathers.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermoplastic resin composition, and more specifically to i-
i A thermoplastic resin composition that has improved moldability, especially adhesion during molding, which is a disadvantage of thermoplastic polyurethane resin (hereinafter abbreviated as TPU), and also has improved compatibility between TPU and other resins. It is related to objects and their films.

(Prior art and its problems) TPU is widely used in the fields of injection molding, extrusion molding, etc. because it has excellent mechanical strength, abrasion resistance, oil resistance, chemical resistance, and cold resistance. However, TPU is extremely sticky during the molding process, and for example, when a thin film is inflated, it is difficult to form a film because of the strong stickiness, or when using T-die extrusion molding.
When producing films and sheets, it is necessary to use carriers such as release paper.

On the other hand, TPU is blended with other elastomers, such as olefin elastomers, styrene thermoplastic elastomers, and polyvinyl chloride, for the purpose of softening and improving quality, but TPU and these elastomers are not compatible. At present, it is not possible to obtain satisfactory results due to the disadvantages and the need for special mixing operations.

(Means for Solving the Problem) The present inventors completed the present invention as a result of intensive research to solve the problem.

That is, the present invention uses thermoplastic polyurethane resin 99-4.
A thermoplastic resin composition comprising 1 to 60% by weight of a styrene-based copolymer (B), a styrene-based copolymer (B), a styrene-based thermoplastic elastomer (C), and a styrene-based thermoplastic elastomer (C) added to the composition. The present invention provides thermoplastic resin compositions and films or sheeters thereof.

According to the present invention, the resulting molded product does not have viscous properties during molding, but exhibits excellent compatibility when blended with other polymers, such as styrene thermoplastic elastomers. .

(Structure) The thermoplastic polyurethane resin used in the present invention is obtained by reacting a high-molecular diol component with a diisocyanate, and a low-molecular diol as a chain extender can also be used in combination.

As the polymer diol component, polyester diol,
Examples include polyether diols, polylactone diols, polyolefin diols, and /liquor net polyols. The number average molecular weight of polymer diol is 300 to 6,00
0 is preferred. The number average molecular weight of low molecular diol is 50
A value smaller than 0 is preferred.

Polyester diols are synthesized by reacting dicarboxylic acids and diols, but as dicarboxylic acids,
For example, dibasic acids such as geltaric acid, azopic acid, succinic acid, speric acid, sepacic acid, methylanopic acid, pimelic acid, phthalic acid, terephthalic acid, isophthalic acid, maleic acid, fumaric acid, and their acid esters and acid hafides. Examples of diols include ethylene glycol, 1,4-butanediol, 1,6-
Hexanediol, 2,2'-dimethyl-1,3-propanediol, propylene glycol, diethylene glycol, neointhyl glycol, cyclohexane-1
, 4-diol, bisphenol-A, and the like.

Polyether diols include, for example, polyethylene glycol, polypropylene gelylcol, polytetramethylene glycol, diols used in the polyester diol, and other necessary polyhydric alcohols such as trimethylolethane. Alkylene oxide, such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, etc., is added using an initiator such as chlorine, trimethylolethane, or glycerin.

Polylactone diol is obtained by ring-opening addition polymerization of lactones such as C-caprolactone, δ-valerolactone, and β-methyl-δ-valerolactone in the presence of the raw material diols for the polyester diol.

Examples of polyolefin diols include polyester diols.

Examples of chain extenders include diamines such as ethylene diamine, propylene cyamine, and hexamethylene diamine, and bisphenol A in addition to diols such as those exemplified as raw materials for polyester diol.

Examples include adducts of 2 to 4 moles of the alkylene oxide to hydroquinone.

- Examples of diisocyanates include hexamethylene diisocyanate, lysine diisocyanate, inphorone diisocyanate, xylene diisocyanate, cyclohexane diisocyanate, toluidine diisocyanate, 2.4-tolylene diisocyanate, 2.6-
) lylene diisocyanate, 4,4'-diphenylmethane diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate), 1,5-naphthylene diisocyanate o-, m- or p-xylylene diisocyanate, tetramethylene diisocyanate Examples include intamethylene diisocyanate and mixtures thereof. Among these, 4.4'-diphenylmethane diisocyanate, hexamethylene diisocyanate), '2.4-tolylene diisocyanate, 2.6-
Tolylene cincyanate and mixtures thereof are preferred.

The maleic anhydride-modified styrenic copolymer (B) used in the present invention is a copolymer of styrene-based compounding strength and maleic anhydride, and can be processed by ordinary bulk polymerization, solution polymerization, suspension polymerization, etc. using radical polymerization. It can be produced by emulsion polymerization.

Its number average molecular weight is preferably 1000 to 5000. As the styrenic compound forming t& (B), styrene, orthomethylstyrene, glossymethylstyrene, dimethylstyrene, methylethylstyrene, tertiary styrene, improvylstyrene, ethylvinyltoluene, or a mixture thereof is used. .

The maleic anhydride-modified styrenic copolymer (B) used in the present invention is composed of a styrene compound and maleic anhydride, but may contain other copolymerizable monomers within a range that does not impair the effects of the present invention. For example, methyl methacrylate, acrylic ester, acrylic acid, methacrylic acid, etc. can be copolymerized.

In the maleic anhydride-modified styrenic compound □ substance (B), the copolymerization ratio of the styrene compound and maleic anhydride is 90 to 40% by weight of the styrene compound and 10 to 60% by weight of maleic anhydride, preferably styrene compound and maleic anhydride. Compound 80
-45% by weight, maleic anhydride-acid 20-550-55% by weight Outside this range, even if mixed with TPU, the desired object cannot be obtained.

In the present invention, the mixing ratio of the TPU prisoner and the maleic anhydride-modified styrenic copolymer (B) is (5) 99 to 60 parts!
L%, (B) 1 to 60% by weight. If it is outside this range, the non-adhesive effect will not be obtained and the compatibility with other polymers, such as styrene thermoplastic elastomers, will be poor. . In particular, (5) is 97 to 60 Jl, and (B) is 3 to 40! in (like)!

The thermoplastic resin composition of the present invention has excellent compatibility with other resins, and particularly shows extremely good compatibility with styrene-based thermoplastic elastomers.

Styrenic thermoplastic elastomer (C) is 5BS (
Styrene-butadiene-styrene [fat] SBR (styrene-butadiene resin), 5BA (styrene-butadiene-acrylic resin), preferably SBR. When this component (C) is added, the mixing ratio of (A):(B) and (C) is preferably 20-65:5-2.
0:30-60(1). As a commercially available product of this type, the SBR resin is CARIFLEX TR-110.
3 (Product of Shell Chemical Co., Ltd.), JR-2000 (Product of Nippon Gohsei Co., Ltd.), JR-3000 as SBS resin
(product of Nippon Gosei Dem Co., Ltd.), etc.

The resin composition of the present invention can be produced by mixing in a tumbler or Henschel mixer, melt-mixing in a -screw or twin-screw extruder, and then forming the resin composition into pellets. can.

The thermoplastic resin composition of the present invention also contains a small amount of flame retardant,
Antistatic agent, release agent, coupling agent, coloring agent, lubricant,
Various additives such as a weathering stabilizer, a foaming agent, a rust preventive agent, an opacifying agent, a fungicide, a plasticizer, and a filler may be added. Examples of the filler include powders such as calcium carbonate, clay, alumina powder, crushed stone powder, talc, sulfuric acid slag, rum, silica/douglas, mica, and glass powder.

Since the resin composition of the present invention has excellent flexibility and non-adhesive properties, it can be used in the form of a film, sheet, or molded product, and is preferably used in the form of a film or sheet.

It is particularly useful as a stretch film for products that often come into contact with people, and is used, for example, in the waist and groin areas of body fluid treatment products such as disposable diapers. The thickness of the film is preferably between 10 and 200 microns, and the thickness of the sheet is
It is thick (200 microns). These films and sheets are manufactured by conventional methods such as extrusion, T-die, and in-line cutting.

In addition, in carrying out the present invention, other thermoplastic resins or elastomers such as polyvinyl chloride, ethylene-he vinyl copolymer, polyester copolymer, NBR may be used without departing from the purpose of the present invention.

It is also possible to use EPR, EPDRyjeliptacene, vinyl chloride elastomer, acrylic polymer, polyamide together with polyimide, polyamideimide, polyphenylene sulfide, etc.

(Effect) The essential components constituting the present invention are a thermoplastic polyurethane resin (4) and a maleic anhydride-modified styrene copolymer (B), and the greater the amount of the (B) component added, the harder it becomes. Therefore, it is useful to appropriately determine the amount added depending on the purpose. Moreover, if the amount added is less than 1 weight LD, the effect of the present invention is small and it is difficult to achieve the present invention.

The resin composition of the present invention thus obtained contains the maleic anhydride-modified styrenic copolymer (B), which has excellent compatibility with the thermoplastic polyurethane resin (A), and therefore has good tensile strength and elongation. Without losing the properties of polyurethane resins, such as excellent film flexibility, film stretchability and appearance (pinholes, rough skin) have been improved, and there is no stickiness during molding or film winding. Excellent film formability. It is a composition. Applications include various industrial materials such as belt hoses, shoe soles, synthetic leather, and molded products made by extrusion and injection molding. In particular, the film obtained by molding the thermoplastic resin composition of the present invention has extremely high practicality as an elastic film for waist gears and leg gears of disposable diapers.

(Examples) The present invention will be specifically explained below with reference to Examples, but the present invention is not limited only to these Examples.

Note that the parts in between mean parts by weight.

The characteristics of the samples obtained on each side were tested using the following method.

(General Mechanical Properties) The resin composition according to the present invention was molded into 10 parts by injection molding machine.
Create 2 sheets of 5t MIX 0.2 tan size and JISK
-7311 (test method for urethane thermoplastic elastomers), test pieces were prepared and subjected to measurement.

(Inflation moldability) The resin composition of the present invention was put into an inflation extruder to form a blown film.

O film! Stretchability: During blown film molding, the stretching ratio is varied to find the minimum film thickness that can be stably produced. It can be said that the thinner the film obtained, the better the compatibility and film formability.

O pinholes: The number of holes in the film area was measured at a time width of 60α and a length of 2 m when a blown film with a thickness of 3 iμ was prepared.

O Adhesion: When a 30 μm blown film was prepared, the adhesion between the inner surfaces of the In7 Rayson film was observed.

Rating 1: There is no adhesiveness between the inner surfaces and it can be easily peeled off.

3: The inner surfaces can be peeled off somehow, but the adhesive strength is significant and the film is greatly deformed when peeled off.

5: Films stick together and cannot be peeled off.

(Examples 1 to 4, Comparative Examples 1 to 2) Each component shown in Table 1 was melt-mixed using a 50 rm extruder and pelletized. The obtained pellets were molded using an injection molding machine to obtain a sheet of 0.2 cm thick, -! Mechanical properties were measured.

On the other hand, the obtained nine-sheet pellet was made into a blown film using an inflation extruder, and the film stretchability, number of pinholes, and adhesiveness were all evaluated, and the results are shown in Table 1.
Ta.

This example shows that the resin composition of the present invention provides a film with no tackiness.

(Examples 5 and 6, Comparative Examples 3 and 4) As shown in Table 2, each component was used in the same manner as in Example 1.
Obtain a sheet with a thickness of 2 crn and measure its general mechanical properties.
In addition, an inflatable film was prepared in the same manner, and its stretchability, pinholes, and adhesiveness were evaluated, and the results are shown in Table 2.

Examples 5, 6, and 9 When blending TPU and styrene elastomer, the inclusion of maleic anhydride-modified styrene copolymer shows good compatibility, and the very thin inflated silicone film has no pinholes or stickiness. On the other hand, as shown in the comparative example, when the maleic acid-modified styrene copolymer was not present, many pinholes were generated and it was confirmed that a good thin film could not be obtained.

Claims (1)

[Claims] 1. (A) Thermoplastic polyurethane resin 40 to 99% by weight
(B) Maleic anhydride-modified styrenic copolymer 1-60
A thermoplastic resin composition consisting of % by weight. 2. A thermoplastic resin composition characterized by adding a styrene thermoplastic elastomer (C) to the thermoplastic resin composition according to claim 1. 3. A film or sheet characterized by using the thermoplastic resin composition according to claims 1 to 2.