JP2005246053A - Deodorant and molded product thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a deodorant without decoloration, generation of streak patterns in appearance owing to decomposition gas, and reduction in deodorant effect, and to provide a molded product with good moldability using the deodorant, in a thermoplastic resin molded product with a deodorant effect, which is obtained by melt-kneading and molding. <P>SOLUTION: The deodorant comprises a polymer prepared by crosslinking a copolymer of polyolefin and an α,β-unsaturated carboxylic acid with metal ions. The metal ion of the deodorant is a bivalent ion. The molded product is obtained by using the deodorant. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a deodorant and a molded article obtained using the deodorant.

  Several attempts have been made in the past to add a deodorizing function to a thermoplastic resin molded article. However, substances with deodorizing ability generally have poor heat resistance, so discoloration is severe when melt-kneaded with a thermoplastic resin, and streaky patterns are generated on the appearance of the molded product due to the influence of decomposition gas. There is a problem that the deodorizing ability that should originally exist is not expressed because it changes to a completely different substance having no deodorizing ability due to heat.

  For example, flavonoids, P-cymene, thymol, and other natural product extraction components with aroma and deodorizing ability generally have poor heat resistance, and after melting and kneading with a thermoplastic resin, these substances decompose to cause discoloration and generation of decomposed gas. In some cases, the deodorizing ability inherently disappeared (Patent Document 1).

  Moreover, an odor component may be limited. For example, Patent Document 2 discloses that a urea derivative and an amidine derivative are melt-kneaded and molded into a polyacetal resin, but the deodorizable odor component is limited to acidic gases such as formaldehyde and acetic acid, and is representative. There was no deodorizing function for ammonia, which is a strong alkaline malodor.

Inorganic fillers such as porous zeolite and sepiolite, and titanium oxide using the photocatalytic action disclosed in Patent Document 3 have heat resistance that can be deodorized over a wide range of odor components and can be melt-kneaded with thermoplastic resins. ing.
However, in order to improve the dispersibility of the inorganic filler, it is necessary to wet the surface with a dispersant such as wax during melt kneading with the thermoplastic resin. As a result, the malodorous molecule adsorption sites on the surface of the inorganic filler were covered, and the deodorizing effect tended to decrease significantly. Furthermore, since the inorganic filler only adsorbs malodorous molecules and develops the deodorizing effect, the deodorizing effect disappears when the adsorption site becomes saturated.
In addition, the photocatalytic deodorant requires that the surface of the titanium oxide is always irradiated with ultraviolet rays in order to decompose and deodorize the odorous components. For example, in a bathroom where the amount of ultraviolet irradiation is low, sufficient deodorization is required. In some cases, the effect was not expressed.

  As a deodorant capable of relatively deodorizing any odor component, a deodorant containing a divalent iron compound and a chelating agent, specifically, a composite in which an EDTA complex of ferrous sulfate is supported on an inorganic filler It is disclosed in Patent Document 4. Since this deodorant has good heat resistance compared to other deodorants, it can be melt-kneaded with a thermoplastic resin. There was a tendency for the deodorizing effect to be remarkably lowered. Furthermore, at a temperature of 160 ° C. or more, which is a general melt kneading temperature of polyolefin resin, there is a problem that the melt kneaded product composed of the deodorant and the thermoplastic resin generates heat and changes its color from milky white to black purple.

Further, when a thin film or fiber is formed by melting and kneading a deodorant into a thermoplastic resin, a high degree of dispersion of the deodorant is required in addition to the above problems.
For example, when a high-concentration deodorant described in Patent Document 4 is contained in a hydrophobic thermoplastic resin such as an olefin resin, the resin and the deodorant can be used even if an advanced pigment dispersion technique is used. The wettability is poor, and the deodorant particles form aggregates during melt-kneading. In the case of film, bumps occurred, and in the case of fiber, the pack pressure of the spinning machine filter increased and the yarn was broken.

  However, if the dispersion level of the deodorant is improved too much, the exposure rate of the deodorant on the surface of the molded product decreases, and the expected deodorizing effect may not be expressed. For example, it has been difficult to develop a deodorizing effect while emphasizing film forming properties, spinnability, tensile elongation and appearance in a long run.

In order to solve this problem, for example, when a deodorizing effect is imparted to the fiber, a large amount of a deodorizing component is contained on the fiber surface as disclosed in Patent Document 5, and only the resin is arranged in the center. A sheath-core type fiber has been proposed, but it goes without saying that a special device and technique are required for the spinning method.
There is also a technology to impregnate deodorant solution on the surface of fiber or film, but in the case of fiber, the deodorant drops off due to repeated washing, and the deodorizing effect decreases, which is not practical. It was.

JP 2001-031516 A JP 2000-034417 A Japanese Patent Application Laid-Open No. 9-074434 Japanese Patent Publication No. 7-12431 JP-A-8-284011

  An object of the present invention is to obtain a deodorant having a high deodorizing effect and good moldability, and a molded product thereof.

  The inventors made extensive studies on a deodorant composition that can be applied to thin films and fibers while taking advantage of the high redox reactivity of metal ions. The metal ions were directly supported on a resin, not an inorganic filler. It has been found that the structure has a deodorizing effect without impairing the moldability and the appearance of the molded product.

  That is, the first invention of the present invention is a deodorant comprising a polymer obtained by crosslinking a copolymer comprising a polyolefin and an α-β unsaturated carboxylic acid with a metal ion.

  2nd invention is a deodorizer as described in 1st invention whose metal ion is a bivalent ion.

  3rd invention is a deodorizer as described in 2nd invention whose metal ion is 1 or more types chosen from magnesium, zinc, aluminum, copper, iron, nickel, and cobalt.

  4th invention is a deodorizer in any one of the 1st-3rd invention whose (alpha) -beta unsaturated carboxylic acid is acrylic acid.

  A fifth invention is a resin composition containing 1 to 60% by weight of the deodorant according to any one of the first to fourth inventions and 40 to 99% by weight of a thermoplastic resin.

  6th invention is a resin composition as described in 5th invention whose thermoplastic resin is polyolefin resin.

  In the seventh invention, the thermoplastic resin is selected from a polyethylene terephthalate resin, a resin having a styrene skeleton and an SEBS (styrene / ethylene / butylene / styrene) resin, or a polycarbonate resin and an SEBS (styrene / ethylene / butylene / styrene) resin. It is the resin composition as described in 5th invention which is 1 or more types.

  The eighth invention is a molded article obtained using the deodorant according to any one of the first to fourth inventions.

  A ninth invention is a molded article obtained using the resin composition according to any one of the fifth to seventh inventions.

  The deodorizer of the present invention has a good deodorizing effect because it comprises a polymer obtained by crosslinking a copolymer comprising a polyolefin and an α-β unsaturated carboxylic acid with a metal ion.

  The deodorizer of the present invention has a high deodorizing effect because the metal ions are divalent ions.

  Furthermore, the deodorizer of the present invention has a high deodorizing effect because the metal ion is one or more selected from magnesium, zinc, aluminum, copper, iron, nickel, and cobalt.

  Furthermore, since the α-β unsaturated carboxylic acid is acrylic acid in the deodorizer of the present invention, both moldability and deodorizing effect are good.

  Since the resin composition of the present invention contains 1 to 60% by weight of the deodorant and 40 to 99% by weight of the thermoplastic resin, the deodorant component can be dispersed well in the thermoplastic resin and the moldability is also good. is there.

  The resin composition of the present invention has better moldability since the thermoplastic resin is a polyolefin resin.

  In the resin composition of the present invention, the thermoplastic resin is a polyethylene terephthalate resin, a resin having a styrene skeleton and an SEBS (styrene / ethylene / butylene / styrene) resin, or a polycarbonate resin and SEBS (styrene / ethylene / butylene / styrene). ) Since it is at least one selected from resins, it has good moldability and mechanical properties.

Since the molded article of the present invention is obtained using the above deodorant or resin composition, it has a high deodorizing effect and good moldability and excellent appearance. In particular, there is no problem of deterioration in spinning characteristics and film appearance due to poor dispersion of the deodorant in the thermoplastic resin, which has been regarded as a problem in the past.
In addition, since the dispersibility and wettability between the deodorant component and the thermoplastic resin are excellent, the mechanical properties, particularly the impact strength, are hardly lowered.
Further, when the molded product is a fiber, there is no possibility that the deodorant is dropped due to repeated washing or the like and the deodorizing ability is not lowered.

<Polymer formed by crosslinking a copolymer of polyolefin and α-β unsaturated carboxylic acid with a metal ion>
The main component in the deodorant of the present invention is a polymer (ionic copolymer) obtained by neutralizing a copolymer comprising a polyolefin and an α-β unsaturated carboxylic acid with a metal ion and ionic crosslinking, so-called ionomer. (Including resin and wax).
<Polyolefin>
The polyolefin used in the present invention is preferably an α-olefin resin such as ethylene or propylene. Particularly preferred are resins having a polyethylene skeleton (including waxes).

<Α-β unsaturated carboxylic acid>
Examples of the α-β unsaturated carboxylic acid used in the present invention include acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid and acid anhydrides and esters thereof. Acrylic acid is particularly preferable.

<Metal ion>
The deodorizer of the present invention uses a mechanism that does not bromide odor components by oxidation-reduction reaction utilizing the reactivity of metal ions. Examples of the metal ion include iron, zinc, calcium, magnesium, aluminum, copper, nickel, cobalt, sodium and the like. These may be used alone or in combination of two or more.
From the viewpoint of high reactivity, divalent ions such as iron, zinc, cobalt, magnesium, and aluminum are preferable. Moreover, zinc, calcium, magnesium, aluminum, etc. are preferable from the viewpoint of low coloring influence on the molded product.

  A divalent metal ion alone is difficult to maintain a reaction active state, but is taken into an ionomer structure and is supported on a resin, so that the reaction active state can be stably maintained. The metal ion concentration in the deodorant molded product is preferably 0.1 to 2%.

<Deodorant>
The deodorizer of the present invention can be obtained by an ordinary ionomer production method. That is, a copolymer obtained by graft polymerization of a polyolefin and an α-β unsaturated carboxylic acid is crosslinked with a metal ion. The deodorant of this invention can be used independently. Furthermore, you may melt-knead with other resin.

<Resin composition>
Further, the deodorant of the present invention and a thermoplastic resin are blended to produce a resin composition (masterbatch) containing a high concentration of the deodorant, and this and an appropriate thermoplastic resin (dilution resin (molding) It is also possible to mold the resin)) into a molded product.
In the resin composition of the present invention, a content of 1 to 60% by weight of a deodorant and 40 to 99% by weight of a thermoplastic resin is preferable from the viewpoints of dispersibility and moldability.

<Thermoplastic resin>
Polyolefin resins such as polyethylene, low density polyethylene, linear low density polyethylene (LLDPE), polypropylene, homopolypropylene, impact polypropylene, etc. as the thermoplastic resin (base resin) used in the resin composition; unsaturated carboxylic acid, Examples include polyolefin resins containing anhydrides or esters thereof; EVA resins, EEA resins, vinyl chloride resins, chlorinated polyethylene resins, polyvinylidene fluoride, polyamides, polyacetals, styrene-modified polyphenylene ethers, polybutenes, polybutadienes and the like.

  Also, a thermoplastic resin that does not necessarily have a good compatibility with the ionomer resin, such as a polyethylene terephthalate resin; a polystyrene resin having a styrene skeleton in the structure, an AS resin, an ABS resin; an unsaturated carboxylic acid, its anhydride or its ester as an olefin A styrene-olefin copolymer having a skeleton; polycarbonate and the like can also be used as a base resin.

  When a styrene resin or a polycarbonate resin is used, SEBS (styrene / ethylene / butylene / styrene) resin is used as a compatibilizing agent for a part of the base resin. As a result, the mechanical properties of the molded product, in particular, the impact strength and the tensile elongation can be prevented from decreasing. The SEBS resin content in the resin composition or molded product is preferably 0.3 to 5% by weight.

  The base resin of the resin composition may be the same resin as the dilution resin used as necessary when manufacturing the molded product, but it is not necessarily the same. For example, when producing a resin composition containing a deodorant in order to produce a polypropylene molded article, the base resin does not necessarily need to use polypropylene, and may be any resin that is relatively compatible with polypropylene. LLDPE polymerized by a metallocene catalyst that can be melt-kneaded at a low temperature can be particularly preferably used.

  The resin composition is obtained by melt-kneading the deodorant and the base resin using a batch kneader such as a Banbury mixer, a continuous kneader such as a single and twin screw extruder, a tandem kneader, or a kneader. .

<Molded product>
The molded article of the present invention can be obtained by injection molding, extrusion molding or the like by using a deodorant as it is or by blending a deodorant resin composition and a dilution resin.

  The content of the deodorant in the molded product varies depending on the required deodorization rate, specifically the length of time until the gas with a specified concentration decreases below the target concentration, and the surface area of the molded product, In order to obtain an effect that is recognized as having deodorant ability, 1% by weight or more is preferable. If it is less than 1% by weight, the decrease in odor concentration may be relatively small depending on the odor component. Further, if the content of the deodorant exceeds 20% by weight, the melting point tends to be low and the heat resistance tends to be low, so 20% by weight or less is preferable depending on the use of the molded product. In particular, 1 to 10% by weight is preferable.

  The shape of the molded article of the present invention is not particularly limited, but the effects of the present invention are remarkably exhibited particularly in a film or yarn that requires a high degree of dispersibility and fibers obtained using the same. Specifically, in the molding of thin films and fibers with a wall thickness of approximately 30 μm or less, a deodorizing effect is imparted without changing the moldability, spinnability and other characteristics compared to those with no deodorant added. it can.

<Other ingredients>
In the deodorant, the resin composition and the molded product of the present invention, additives used for ordinary thermoplastic resins and molded products can be used as necessary.
Titanium white, titanium yellow, disazo yellow, isoindolinone yellow, polyazo yellow, polyazo red, quinacridone red, DPP red, perylene red, phthalocyanine green, phthalocyanine blue, petal, ultramarine, dioxazine violet, carbon black, Iron black etc. are mentioned. These may be used alone or in combination of two or more.

As the antioxidant, one type or two or more types of antioxidants such as phenol type, phosphorus type, sulfur type, and lactone type used for preventing thermal deterioration during resin processing are used.
As the ultraviolet absorber and light stabilizer, benzophenone, hindered amine, benzotriazole, nickel quencher, cyanoacrylate compounds and the like are used.
Antistatic agents include cationic, anionic, and nonionic types. In general, nonionic antistatic agents with good heat resistance are preferably used. It is also possible to use polymer-type permanent antistatic agents developed in recent years.
In addition, it is possible to improve the rigidity and heat distortion resistance of the molded product by containing an inorganic filler such as talc, mica, calcium carbonate, barium sulfate, clay, and silica.

  Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. “%” Means “% by weight” and “parts” means “parts by weight”. The materials used are listed in Table 1.

[Example 1]
A blend composed of 50% ionomer wax-1 and 50% polypropylene was mixed with a Henschel mixer for 3 minutes, and then melt-kneaded in a twin-screw extruder with a cylinder port of 180 ° C. and a L / D = 32 vent port.
A die having a hole with a diameter of 3 mm was charged at the outlet of the twin-screw extruder, the strand-like kneaded product was extruded, and granulated into a pellet with a length of 3 mm by a rotary cutter to obtain a master batch.

After 100 parts of polypropylene, 0, 2, 10, and 20 parts of the masterbatch (each additive-free product, actual 1-2, actual 1-10, and actual 1-20) were dry blended, and set temperature Melt spinning was performed with a spinning machine loaded with a filter having a mesh size of 2 microns and 250 ° C., and a fiber having a fineness of 15 denier was obtained.
At this time, the increase value of the filter pack pressure before and after melt spinning 1 kg of the material with a spinning machine was measured.

  3 g of each of the above fibers was put into a 3 L volume odor bag (flex sampler manufactured by Omi Odo Air Service Co., Ltd.) and vacuumed, and then 50 ppm of ammonia gas was filled. The ammonia gas concentration immediately after starting the test and after standing for 3 hours in a dark place at 23 ° C was measured with a gas detector tube (gas detector tube No. 3La made by Gastec). It was determined that the deodorizing effect was high.

[Example 2]
The same operation as in Example 1 was performed except that the ionomer wax-1 in Example 1 was changed to ionomer wax-2.

[Example 3]
The same operation as in Example 1 was performed except that the ionomer wax-1 in Example 1 was changed to an ionomer resin. Moreover, the same operation as Example 1 was performed using the formulation which consists of ionomer resin 100% (exact 3-100).

[Comparative Example 1]
The same operation as in Example 1 was performed except that the ionomer wax-1 in Example 1 was changed to a deodorant mainly composed of an iron-EDTA complex. When 8.3% of the above deodorant was contained (ratio 1-20), foaming occurred with an increase in pack pressure during melt spinning, making spinning impossible.

[Comparative Example 2]
The same operation as in Example 1 was performed except that the ionomer wax-1 in Example 1 was changed to titanium oxide.

[Comparative Example 3]
The same operation as in Example 1 was performed except that the ionomer wax-1 in Example 1 was changed to zinc oxide.

[Example 4]
Ionomer Wax-1 50%, polyethylene 49.9%, phenolic antioxidant 0.1% blended for 3 minutes in a Henschel mixer, cylinder temperature 160 ° C., L / D = 32 with vent port 2 Melt kneading was carried out using a shaft extruder.
A die having a hole with a diameter of 3 mm was charged at the outlet of the twin-screw extruder, the strand-like kneaded product was extruded, and granulated into a pellet with a length of 3 mm by a rotary cutter to obtain a master batch.

100 parts of polyethylene, 0, 2, 10 and 20 parts of the masterbatch are added and then dry blended. Film forming with an inflation film forming machine equipped with a set temperature of 180 ° C and a screen mesh opening filter of 60 microns. To obtain a film with a thickness of 20 μm.
The number of bumps with a diameter of 200 μm or more in 100 cm ² of this film was measured.
Next, the deodorizing effect measurement similar to Example 1 was performed using each 500 cm < ² > of films obtained by the said operation.

[Example 5]
The same operation as in Example 4 was performed except that the ionomer wax-1 in Example 4 was changed to an ionomer resin.

[Comparative Example 4]
The same operation as in Example 4 was performed except that the ionomer wax-1 in Example 4 was changed to a deodorant mainly composed of an iron-EDTA complex.

[Comparative Example 5]
The same operation as in Example 4 was performed except that the ionomer wax-1 in Example 4 was changed to titanium oxide.

[Comparative Example 6]
The same operation as in Example 4 was performed except that the ionomer wax-1 in Example 4 was changed to zinc oxide.

[Example 6]
A blend consisting of 50% ionomer resin, 29.9% polystyrene, 20% SEBS, 0.1% phenolic antioxidant is mixed for 3 minutes with a Henschel mixer, and then has a vent at a cylinder temperature of 200 ° C. and L / D = 32. Melt kneading was performed using a twin screw extruder.
A die having a hole with a diameter of 3 mm was charged at the outlet of the twin-screw extruder, the strand-like kneaded product was extruded, and granulated into a pellet with a length of 3 mm by a rotary cutter to obtain a master batch.

Add 100 parts of polystyrene to the masterbatch, add 0, 2, 10 and 20 parts each, then dry blend and perform injection molding on an injection molding machine with a set temperature of 220 ° C and a mold temperature of 40 ° C to obtain a 3mm thick flat plate Got.
This flat plate was cut to prepare an Izod test piece, and the Izod impact strength at 23 ° C. was measured based on ASTM D256.
Moreover, the deodorizing effect measurement similar to Example 1 was performed using each flat plate 500cm < ² > obtained by the said operation.

[Comparative Example 7]
The same operation as in Example 6 was performed except that SEBS in Example 6 was replaced with polystyrene.

[Description of table]
In the examples, almost no increase in the filter pack pressure during spinning or the number of bumps during film formation was observed. On the other hand, in all of the comparative examples, an increase in pack pressure and a significant increase in the number of hits were observed.
It was also found that the deodorizing effect was good when the content of ionomer (resin or wax) in the molded product was 1% by weight or more.
None of the molded articles obtained in the examples were discolored, but in Comparative Examples 1 and 4 (deodorants based on iron-EDTA complexes), significant discoloration occurred.
When Example 6 and Comparative Example 6 were compared, it was found that Comparative Example 6 containing no SEBS had low Izod impact strength and was difficult to use as a molded product.

  Since the deodorant of the present invention chemically reacts with a substance to be deodorized, it has excellent immediate effect, and since the deodorant itself is a thermally and chemically stable material, a wide range of films, nonwoven fabrics, molded products, fibers, etc. In addition to applications, it can be applied to applications that require rubber elasticity and impact resistance by taking advantage of the properties of ionomers.

Claims (9)

A deodorant comprising a polymer obtained by crosslinking a copolymer comprising a polyolefin and an α-β unsaturated carboxylic acid with a metal ion. The deodorizer according to claim 1, wherein the metal ion is a divalent ion. The deodorizer according to claim 2, wherein the metal ion is at least one selected from magnesium, zinc, aluminum, copper, iron, nickel, and cobalt. The deodorizer according to any one of claims 1 to 3, wherein the α-β unsaturated carboxylic acid is acrylic acid. A resin composition comprising 1 to 60% by weight of the deodorant according to any one of claims 1 to 4 and 40 to 99% by weight of a thermoplastic resin. The resin composition according to claim 5, wherein the thermoplastic resin is a polyolefin resin. The thermoplastic resin is one or more selected from polyethylene terephthalate resin, resin having a styrene skeleton and SEBS (styrene / ethylene / butylene / styrene) resin, or polycarbonate resin and SEBS (styrene / ethylene / butylene / styrene) resin. The resin composition according to claim 5. The molded article obtained using the deodorizer in any one of Claims 1-4. A molded article obtained using the resin composition according to claim 5.