JP2008001840A - Transparent vinyl chloride resin composition and molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vinyl chloride resin composition having excellent transparency, moldability and impact resistance simultaneously together with excellent other various characteristics without containing PRTR materials such as lead and a tributyltin compound, and to provide its molded product. <P>SOLUTION: The transparent vinyl chloride resin composition contains 0.5-5 pts.wt. of a stabilizer and 0.1-5 pts.wt. of a lubricant, based on 100 pts.wt. of a vinyl chloride resin. The stabilizer is a metallic soap-based stabilizer, and the lubricant is a modified polyethylene having 0.1-70 mg KOH/g acid value, 920-980 kg/m<SP>3</SP>density and 900-8,000 molecular weight, and/or a polypropylene having 2,000-20,000 molecular weight. In the composition, a chlorinated polyethylene having 30-50 wt.% chlorine content and 1.50-1.55 refractive index, may be used as an impact resistance improver. Where the content of the impact resistance improver is 1-10 pts.wt. per 100 pts.wt. of the vinyl chloride resin, allowing the use of the polypropylene by alone as the lubricant. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a transparent hard vinyl chloride resin composition and a molded product thereof.
Specifically, it has excellent transparency, moldability, and impact resistance without including PRTR (Pollutant Release and Transfer Register) target substances such as lead and tributyltin compounds. The present invention relates to a vinyl chloride resin composition excellent in various properties and a molded body thereof.

Vinyl chloride resin is excellent in mechanical strength, weather resistance, and chemical resistance, and is less expensive than other plastic materials, so it is used in a wide range of water supply and drainage pipes, plates, joints, etc. Yes.
Since these vinyl chloride resins are close to the molding temperature region and the decomposition temperature region, it is difficult to mold the resin alone, and a (thermal) stabilizer is generally used at the time of molding.

As a (heat) stabilizer for vinyl chloride resins, various types of stabilizers such as inorganic, organic and metal soaps have been developed. Among these various stabilizers, lead-based stabilizers that are superior in performance (e.g., increased transparency of molded products) and cost have been used for a long time, and are known as typical thermal stabilizers. It has been.
However, in recent years, interest in environmental issues has increased, and the safety of heavy metals, especially the toxicity of lead, has become a problem, and the need for low and non-toxic heat stabilizers for polyvinyl chloride (PVC) has increased. ing.
In place of this lead-based stabilizer, tin-based stabilizers other than butyltin and metal soap-based composite stabilizers have been highlighted as stabilizers that are environmentally friendly and can enhance transparency.

Most of the tin-based stabilizers are liquid, and when used, high transparency can be obtained. On the other hand, the slipperiness of the molten resin during molding processing decreases, and the heat distortion temperature (flexible temperature) of the molded product. There is a problem that decreases.
On the other hand, metal soap stabilizers (hereinafter also referred to as “metal soaps”) have higher lubricity of molten resin and less decrease in softening temperature of molded products than tin stabilizers. Therefore, the compounding prescription requires an inorganic compound-based stabilizing aid such as zeolite or hydrotalcite, and there is a problem that these stabilizing aids inhibit transparency.

  If a powdered metal soap or the like is uniformly dispersed in the resin, the light transmittance is increased and the transparency of the molded article is excellent. Recently, studies for achieving this uniform dispersion (for example, adding a dispersion aid) have been actively conducted.

In addition, a smooth flow of the resin inside the molding machine is difficult to occur, and separation or decomposition of the resin composition may occur in a portion where the flow is stagnant. Therefore, in the case of hard vinyl chloride, it is common to add (external) lubricant to improve the moldability. Various types of lubricants have been developed as well as stabilizers, but many of them cause loss of transparency.
Furthermore, in hard vinyl chloride (unlike soft vinyl chloride), it is necessary to impart impact resistance to a molded product, and therefore an impact modifier is generally added. As with the above stabilizers and lubricants, many of the impact modifiers cause a loss of transparency.

JP-A-5-271355

  In consideration of the above points, the present invention has excellent transparency without requiring the addition of a dispersion aid in hard applications, and has excellent processability during molding (viscosity of melt, thermal stability, gelation). Provides a transparent vinyl chloride resin composition that does not contain a PRTR target substance and has a good impact resistance and appearance after molding, and maintains a high flexibility temperature, and a molded product thereof. The task is to do.

In order to solve the above problems, the present inventors first focused on (1) using a metal soap-based stabilizer as a thermal stabilizer not containing a PRTR target substance in order to obtain excellent transparency. However, the study focused on the technology of uniformly dispersing the metal soap stabilizer and the accompanying inorganic compound stabilizer.
Therefore, the present inventors have conducted extensive research to find a lubricant that can achieve uniform dispersion of metal soap or the like (that is, has a role as a dispersion aid). 2) It was found that a specific modified polyethylene is effective.

  Next, in order to improve the processability of hard vinyl chloride, the present inventors have repeatedly studied to find a lubricant having an activity as a good external lubricant in order to obtain excellent moldability. (3) It has been found that even when a specific polypropylene is added in a small amount, the effect of reducing the viscosity of the melt is great, and the decrease in the flexible temperature of the molded product can be suppressed.

That is, in the present invention, it is most suitable to use “(1) metal soap stabilizer” as an essential component and “(2) specific modified polyethylene” and / or “(3) specific polypropylene” as a lubricant. The purpose (resin composition having both transparency and molding processability), and according to the combination of (1) to (3), the use of a plasticizer and a dispersion aid can be reduced (to zero). Can also be played.
In addition, by selecting these “metal soap stabilizers”, “specific modified polyethylene”, and “specific polypropylene” from infinitely existing stabilizers and lubricants, hard vinyl chloride contains PRTR substances. The present inventors have found that excellent transparency and molding processability can be ensured, and that other various characteristics can also be improved.

The present inventors have further studied to search for an impact modifier that does not impair the transparency of the vinyl chloride resin in order to obtain excellent impact resistance. (4) Specific chlorine It has been found that the modified polyethylene not only can provide excellent impact resistance, but also has a role as a dispersion aid in addition to good compatibility with the vinyl chloride resin.
That is, this “(4) specific chlorinated polyethylene” has the effect of achieving uniform dispersion of metal soap and the like, as in the case of “(1) specific modified polyethylene”, and has excellent transparency of the molded product. Can be. For this reason, by using this “specific chlorinated polyethylene”, transparency and impact resistance can be improved without using the “specific modified polyethylene”.

The present invention has been achieved under the above knowledge. Transparent chloride containing 0.5 to 5 parts by weight of stabilizer and 0.1 to 5 parts by weight of lubricant with respect to 100 parts by weight of vinyl chloride resin. A vinyl resin composition, wherein the stabilizer is a metal soap stabilizer, and the lubricant is an acid value (acid value: mg of potassium hydroxide required to neutralize an acidic component contained in 1 g of a sample. Number) Transparent vinyl chloride resin composition characterized by being 0.01 to 70 mg KOH / g, a density of 920 to 980 kg / m ³ , a modified polyethylene having a molecular weight of 900 to 8000, and / or a polypropylene having a molecular weight of 2000 to 20000. Is the gist.
Further, the present invention may further contain 1 to 10 parts by weight of chlorinated polyethylene having a chlorine content of 30 to 50% by weight and a refractive index of 1.50 to 1.55 as an impact modifier. May be only polypropylene having a molecular weight of 2000 to 20000.
And as a stabilizer, you may contain at least 1 sort (s) of a methyl tin compound and an octyl tin compound so that it may become 0.1 to 50 weight% in the total amount with a metal soap type stabilizer.

Further, the molded product obtained from the transparent vinyl chloride resin composition of the present invention has a total light transmittance of 60% or more as measured by JIS-K-7361-1 at a thickness of 1 mm, and is measured by the Crashberg method. The softening temperature is 70 ° C. or higher.
And the molded object obtained from the composition which further contains said impact improving agent has a drop height of 60 cm or more when 50% is destroyed in a drop weight test at 0 ° C. and a 1 kg weight.

As the vinyl chloride resin in the present invention, in addition to homopolymer polyvinyl chloride, copolymers such as vinyl chloride-ethylene copolymer, vinyl chloride-vinyl acetate copolymer, vinyl chloride-acrylic copolymer are also used. In addition, so-called post-chlorinated vinyl chloride resins obtained by post-chlorinating these can also be used (unless otherwise specified, the term “vinyl chloride-based resin” refers to post-chlorine Any of these may be used alone or in admixture of two or more of appropriate combinations.
The average degree of polymerization of these vinyl chloride resins is about 500 to 3000, preferably about 700 to 1500. When the average degree of polymerization is less than 500, the mechanical strength is low, and when it exceeds 3000, the melt viscosity is high and the molding process becomes difficult.

The content of the stabilizer in the transparent vinyl chloride resin composition is 0.5 to 5 parts by weight, preferably 1 to 3 parts, relative to 100 parts by weight of the vinyl chloride resin, from the viewpoints of thermal stability and mechanical strength. Parts by weight.
If the amount is less than 0.5 part by weight, sufficient thermal stability cannot be obtained. If the amount exceeds 5 parts by weight, not only the thermal stability effect is saturated, but also the heat distortion temperature and mechanical strength of the molded body are lowered. Further, since uniform dispersion becomes difficult, transparency is hindered.

It is important to use a powdery metal soap stabilizer as the stabilizer in the present invention.
The metal soap stabilizer is not particularly limited as long as the metal of the metal soap is other than lead or cadmium (so-called non-toxic metal).
In addition, a composite metal soap in which a metal of a metal soap is combined can be used. Examples of the metal combination in this case include barium / zinc, calcium / zinc, magnesium / zinc, and barium / calcium / zinc. System, calcium / magnesium / zinc system, and the like.
The fatty acid of the metal soap is not particularly limited. For example, 2-ethylhexoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, hydroxystearic acid, oleic acid, ricinoleic acid, linoleic acid, Examples include behenic acid and benzoic acid.
Especially, in order to balance transparency and moldability, a combination of calcium stearate and zinc stearate can be preferably used.

  In the present invention, since the purpose is hard vinyl chloride, the amount of use is limited to a small amount, but liquid metal soap stabilizers such as zinc benzoate and zinc 2-ethylhexylate can also be used.

  In the present invention, a stabilizing aid may be added to supplement the thermal stability of the metal soap stabilizer. Examples of the stabilizing aid include inorganic compounds such as hydrotalcite, zeolite, magnesium oxide, and magnesium hydroxide. Among them, magnesium oxide and magnesium hydroxide that do not impair transparency are within the range (uniformly dispersed). (For example, about 1 to 10 parts by weight with respect to 100 parts by weight of the metal soap stabilizer).

The content of the lubricant in the transparent vinyl chloride resin composition is 0 with respect to 100 parts by weight of the vinyl chloride resin from the viewpoint of transparency (dispersibility of metal soap) and lubricity as an external lubricant during molding. 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight.
If the amount is less than 0.1 part by weight, the role of the metal soap as a dispersion aid is poor and good transparency cannot be obtained, and the effect of improving workability by reducing the viscosity is small. When the amount exceeds 5 parts by weight, the appearance of the molded article is deteriorated and impact resistance is lowered.

The lubricant in the present invention is a modified polyethylene having an acid value of 0.01 to 70 mgKOH / g, a density of 920 to 980 kg / m ³ and a molecular weight of 900 to 8000, and / or a polypropylene having a molecular weight of 2000 to 20000. That is weight.
By using such a lubricant, a uniform dispersion state of the metal soap stabilizer and the accompanying inorganic compound stabilizer can be achieved even under conditions where the amount of the dispersion aid is minimized or zero. And a rigid vinyl chloride resin having excellent transparency can be obtained.

The modified polyethylene used in the present invention is an unmodified polyethylene (hereinafter also referred to as “raw polyethylene”) as long as the acid value, density and molecular weight are within the above ranges after modification. The modification method is not particularly limited, and a conventionally known method shown in JP-A-5-271355 may be used. Examples thereof include oxidative modification and acid graft modification.
The oxidative modification is performed by bringing the raw polyethylene into contact with oxygen or an oxygen-containing gas under stirring in the molten state, and the acid graft modification is performed by adding low molecular weight polyethylene to unsaturated carboxylic acid such as maleic acid or maleic anhydride or the like. The modified polyethylene can be obtained by graft copolymerization of the derivatives.

The raw polyethylene is not particularly limited as long as it is an ethylene homopolymer or a copolymer of ethylene and α-olefin, which can obtain a modified polyethylene having the above acid value, density and molecular weight after modification.
As this α-olefin, an α-olefin having 3 to 8 carbon atoms such as propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene and 1-octene is preferable.

The acid value of the modified polyethylene is 0.01 to 70 mgKOH / g, preferably 1 to 30 mgKOH / g.
When the acid value is less than 0.01 mgKOH / g, the effect of improving the dispersibility of the inorganic compound as a metal soap stabilizer or stabilization aid is small, and when it exceeds 70 mgKOH / g, the raw material polyethylene is modified. The production stability at the time is reduced, the affinity with the vinyl chloride resin is increased, and the effect of imparting lubricity is reduced.

The density of the modified polyethylene is measured by a density gradient tube method shown in JISK6760, and is 920 to 980 kg / m ³ , preferably 930 to 980 kg / m ³ .
By setting the density within the above range, the refractive index of the modified polyethylene can be made the same as that of the vinyl chloride resin (about 1.51-1.54). When mixed, the permeability becomes high. As a result, the vinyl chloride resin molded product can ensure excellent transparency.
When the density is less than 920 kg / m ³ , the refractive index of the modified polyethylene becomes 1.50 or less, and when it exceeds 980 kg / m ³ , the refractive index of the modified polyethylene becomes 1.55 or more, and the transparency decreases. .

The molecular weight of the modified polyethylene is measured by a viscosity method, and is 900 to 8000, preferably 1000 to 5000 in the present invention.
When the molecular weight is less than 900, the effect of improving the workability due to the decrease in viscosity is low, and when it exceeds 8000, kneading unevenness is likely to occur and the appearance of the molded article is deteriorated.

In the present invention, as the lubricant, not only the modified polyethylene as described above is used alone, but also a specific polypropylene may be used alone. Furthermore, the modified polyethylene and the polypropylene may be used in combination.
Since this specific polypropylene has a large effect of reducing the viscosity of the melt when used in a small amount, the effect of suppressing a decrease in the softening temperature of the obtained molded product can be ensured. Therefore, by using together with the above-mentioned modified polyethylene, it is possible to obtain not only excellent transparency but also excellent moldability or excellent dimensional and shape stability of the molded body.
When a modified polyethylene and polypropylene are used in combination as a lubricant, the blending ratio is 100: 0 to 60:40, preferably 90:10 to 70:30, by weight. If the proportion of polypropylene is too large, it is not possible to obtain a uniform dispersion effect such as metal soap by modified polyethylene, and if it is too small, it is not possible to obtain a viscosity reducing effect by polypropylene.

The polypropylene of the present invention has a molecular weight measured by a viscosity method of 2000 to 20000, preferably 3000 to 15000.
When the molecular weight is less than 2000 or exceeds 20000, problems occur with respect to workability due to a decrease in viscosity and appearance of the molded body, as in the case of the modified polyethylene.

As said polypropylene, if the molecular weight is in the said range, the propylene homopolymer used normally can be used as it is.
Copolymers with α-olefins can also be used. Examples of α-olefins include carbon atoms such as ethylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene. 3-8 alpha olefins can be used preferably.

  By using the modified polyethylene and / or polypropylene having the acid value, density, and molecular weight as described above as a lubricant, it is possible to uniformly disperse the powdered metal soap and the accompanying stabilizing aid, In addition, an increase in melt viscosity and a decrease in softening temperature can be suppressed, and as a result, a vinyl chloride resin composition having both excellent transparency and moldability can be obtained.

  Further, in the present invention, the lubricant has the same action as a dispersion aid similar to the modified polyethylene (that is, the powdered metal soap and the accompanying stabilization aid can be uniformly dispersed). One important feature is the use of chlorinated polyethylene as an impact modifier.

It is important that the chlorinated polyethylene as the impact modifier has a chlorine content of 30 to 50% by weight and a refractive index of 1.50 to 1.55.
By using this chlorinated polyethylene as an impact modifier, it is possible to achieve not only excellent impact resistance, but also a uniform dispersion state of a metal soap stabilizer and an accompanying inorganic compound stabilizer, In addition, a hard vinyl chloride resin molded body having high transparency can be obtained.
In order to express such an action well, in the present invention, it is suitable to use a chlorinated polyethylene having a molecular weight of about 200,000 to 350,000.

  If chlorinated polyethylene used in the present invention is ordinary polyethylene (hereinafter, also referred to as “raw polyethylene”), after chlorination, the chlorine content and the refractive index are in the above ranges, the chlorinated polyethylene becomes chlorinated polyethylene. The chlorination method is not particularly limited. For example, a method of chlorinating powdered polyethylene by introducing gaseous chlorine in an aqueous suspension with the temperature raised to near the melting point. Such a conventionally known method may be used. Alternatively, commercially available chlorinated polyethylene having a desired chlorine content and refractive index may be used.

  As this raw material polyethylene, similar to the raw material polyethylene of the modified polyethylene described above, an ethylene homopolymer or an ethylene and α-olefin obtained from chlorinated polyethylene having the above chlorine content and refractive index after chlorination is obtained. If it is a copolymer, it will not specifically limit.

The chlorine content of the chlorinated polyethylene as the impact modifier is 30 to 50% by weight, preferably 35 to 45% by weight.
When a post-chlorinated vinyl chloride resin is used as the base vinyl chloride resin, the chlorine content of chlorinated polyethylene as an impact modifier is increased within the above range (specifically, 50 to It is preferably set to about 40% by weight.
If the chlorine content is less than 30% by weight, the compatibility with the vinyl chloride resin (matrix) decreases. If the chlorine content exceeds 50% by weight, the composition is not uniformly chlorinated during the chlorination reaction and the composition is thermally stable. Low.

The refractive index of chlorinated polyethylene is 1.50 to 1.55, preferably 1.53 to 1.54.
If the refractive index is within this range, the refractive index (about 1.51-1.54) of the vinyl chloride resin (matrix) can be set to the same level. Since the permeability becomes high, as a result, the vinyl chloride resin molded product can ensure excellent transparency.
Therefore, if the refractive index of chlorinated polyethylene is less than 1.50 or exceeds 1.55, the refractive index of the chlorinated polyethylene deviates from that of the vinyl chloride resin, so that the transparency is lowered.

The content of the above-mentioned impact modifier is 1 to 10 parts by weight, preferably 100 parts by weight of vinyl chloride resin, from the viewpoint of transparency (dispersibility of metal soap), impact resistance of the molded product, softening temperature, and the like. Is 3 to 5 parts by weight.
When the amount is less than 1 part by weight, the role of the metal soap as a dispersion aid is poor and good transparency cannot be obtained, and when the amount exceeds 10 parts by weight, the softening temperature of the molded article decreases greatly.

In the present invention, chlorinated polyethylene having the above-mentioned chlorine content and refractive index is used as an impact modifier, and by blending at the above-mentioned content, powdered metal soap and accompanying stabilizing aids can be obtained. It can disperse | distribute uniformly and can improve the impact resistance of the molded object obtained.
At this time, the above-mentioned modified polyethylene and / or the above-mentioned polypropylene may be used as the lubricant, but the above-mentioned chlorinated polyethylene as the impact modifier is uniformly coated with metal soap and stabilizing aid as in the modified polyethylene. Since it has a dispersing action, it is possible to suppress an increase in melt viscosity and a decrease in softening temperature only by using polypropylene without using modified polyethylene.
As a result, by using chlorinated polyethylene, which is less expensive than modified polyethylene, a vinyl chloride resin composition having excellent impact resistance, transparency and molding processability, and its molded product, are advantageous in terms of cost. An unexpected effect that it can be obtained can be achieved.

Furthermore, in the vinyl chloride resin of the present invention, in order to ensure better transparency, a methyltin compound and / or an octyltin compound that is not a PRTR target substance may be used in combination as a stabilizer. Is preferably 0.1 to 70% by weight in the total amount with the metal soap stabilizer.
If the content of these tin compounds is too small relative to the metal soap-based stabilizer, the technical significance of using these tin compounds in combination (the effect of increasing transparency) will not be manifested. The slipperiness of the melt is lowered, and the heat distortion temperature (softening temperature) of the molded body is lowered.

  Examples of the methyl tin compound include dimethyl tin laurate, dimethyl tin malate, methyl tin mercapto, dimethyl tin mercapto, dimethyl tin mercaptoacetate, methyl tin isooctyl thioglycolate, methyl tin sulfide, and the like. , Dioctyl tin laurate, dioctyl tin malate, octyl tin mercapto, dioctyl tin dimercapto, dioctyl tin mercaptoacetate, octyl tin isooctyl thioglycolate, octyl tin sulfide and the like.

  Moreover, in this invention, in order to improve the fluidity | liquidity at the time of shaping | molding other than the said metal soap type | system | group stabilizer and a tin compound, you may add a polyhydric alcohol and / or polymethylmethacrylate as needed. As the polyhydric alcohol, polyols such as pentaerythritol, dipentaerythritol and tripentaerythritol, mixtures thereof and ester compounds can be preferably used.

In addition, in the present invention, an antistatic agent, a flame retardant, a processing aid, an ultraviolet absorber, a pigment / dye, etc., if necessary, as long as the characteristics (transparency, molding processability, etc.) of the present invention are not impaired. Various additives such as a colorant can be added as appropriate.
As these antistatic agents, flame retardants, processing aids, ultraviolet absorbers, colorants and the like, ordinary compounds blended in ordinary vinyl chloride resins can be used.

  In the transparent vinyl chloride resin composition of the present invention, a predetermined amount of vinyl chloride resin is mixed with a stabilizer, a lubricant, an impact modifier, and other appropriate compounding agents using a super mixer, a Henschel mixer, a blender, or the like. Can be obtained.

The composition thus obtained is processed by known means such as extrusion molding, calendar molding, press molding, and the like, and the processing method is appropriately selected depending on the purpose.
The molded body of the present invention has predetermined transparency, molding processability, impact resistance, and other characteristics according to predetermined evaluation criteria.

  Moreover, in this invention, when it is set as a molded object with a thickness of 1 mm, the total light transmittance measured according to JIS-K-7361-1 is 60% or more, and the flexible temperature measured by the Crashberg method is 70 ° C. That is important.

If the total light transmittance is less than 60%, sufficient transparency cannot be obtained. The upper limit of the total light transmittance is not particularly limited, and is preferably higher, but about 75 to 80% is sufficient for practical use.
If the molded article has the total light transmittance as described above, the metal soap stabilizer and the like are uniformly dispersed even in the hard vinyl chloride, and the excellent transparency desired in the present invention. It can be set as the molded object which has property.

  Further, when the flexible temperature is less than 70 ° C., warping and deformation occur at high temperatures such as in summer. The upper limit of the flexible temperature is not particularly limited and is preferably higher. However, in practice, it is sufficient if the temperature is within the range of the temperature increase (75 to 80 ° C.) that may occur in summer.

  Furthermore, it is important that the molded body according to the present invention has a drop height of 60 cm or more when it is destroyed by 50% in a drop weight test at 0 ° C. and a 1 kg weight.

If a weight with a weight of 1 kg is dropped and the falling height of the weight when the molded plate is destroyed by 50% is less than 60 cm, cracks and chips will occur when nailing during construction in winter. . The upper limit of the 50% fracture height is not particularly limited and is preferably higher, but about 100 cm is sufficient for practical use.
If the molded body has a 50% fracture height as described above, a molded body having excellent impact resistance desired in the present invention can be obtained.

And the moldability of the transparent vinyl chloride resin composition in the present invention is based on whether or not the composition is excellent in thermal stability.
This thermal stability can be evaluated by the decomposition time in the plastmill.
In the present invention, those having a decomposition time of 10 minutes or more are suitable. If it is less than 10 minutes, the thermal stability at the time of molding is lowered, and the molded product is burnt in color, and there is a problem in quality and molding due to the generation of carbides.

The impact resistance in the present invention is such that a molded article obtained from a transparent vinyl chloride resin composition falls, for example, when heavy objects are used indoors or outdoors as building materials, and flying objects (gravel, tiles, pebbles) Etc.) means sufficient strength to withstand impacts in the event of a collision.
In the present invention, it is important to have a characteristic (impact resistance) that can sufficiently withstand an impact during indoor and outdoor use.

The transparent vinyl chloride resin composition not containing a PRTR target substance according to the present invention and its molded product have excellent transparency without requiring the addition of a dispersion aid in hard applications, and processability during molding ( (Viscosity, thermal stability and gelation time) of the melt is good, so it can be produced using existing molding methods and molding machines, and has excellent impact resistance and appearance after molding, and high flexibility temperature. Have
The molded body of the resin composition of the present invention having such excellent properties is suitable as a material for water / drainage pipes, plates, joints, corrugated plates, etc., particularly as a material for outdoor use.

[Examples 1 to 10, Comparative Examples 1 to 7]
Add the following vinyl chloride resin, stabilizer, lubricant (modified polyethylene, specific polypropylene), impact modifier (chlorinated polyethylene), tin compound, and other compounding agents in the proportions shown in Tables 1 and 2, The mixture was mixed using a mixer to prepare a vinyl chloride resin composition.
The numbers in Tables 1 and 2 indicate parts by weight.

(Raw materials used)
Vinyl chloride resin: Polyvinyl chloride with a polymerization degree of 1050 (vinyl chloride homopolymer, trade name “TK-1000” manufactured by Shin-Etsu Chemical Co., Ltd.)
Metal soap stabilizers: calcium stearate, zinc stearate (trade names “NT-C1, NT-Z1” manufactured by Mizusawa Chemical Co., Ltd.)
Stabilization aid (inorganic compound type): Magnesium hydroxide (trade name “magnesium hydroxide 10A” manufactured by Kamishima Chemical Co., Ltd.)
Tin-based stabilizer (tin-based stabilizer other than methyltin compound and octyltin compound): dibutyltin mercapto (tin 16 wt%) (trade name “TN-480” manufactured by Sakai Chemical Industry Co., Ltd.)
Lubricant (modified polyethylene): polyethylene having an acid value of 1 mg KOH / g, a density of 930 kg / m ³ , and a molecular weight of 4000 by oxidation modification (ethylene homopolymer, trade name “Sun Wax LEL-400P” manufactured by Sanyo Chemical Co., Ltd.)
Lubricant (Polypropylene): Polypropylene having a molecular weight of 4000 (Propylene homopolymer, trade name “Biscol 550P” manufactured by Sanyo Kasei Co., Ltd.)
Impact modifier (chlorinated polyethylene): Chlorinated polyethylene having a chlorine content of 40% by weight, a refractive index of 1.53, and a molecular weight of 50000 of the raw material polyethylene (ethylene homopolymer, trade name “Elaslene 404B” manufactured by Showa Denko KK)
Methyl tin compound: dimethyl tin mercapto (tin 15.5 wt%) (trade name “MK-6” manufactured by Sakai Chemical Industry Co., Ltd.)
Octyltin compound: Dioctyltin mercapto (tin 15.8 wt%) (trade name “TN-870” manufactured by Sakai Chemical Industry Co., Ltd.)
Processing aid: Acrylic processing aid (Mitsubishi Rayon Co., Ltd., trade name “Metabrene P-551A”)

  About the obtained composition, each characteristic was evaluated by the following evaluation method, and this result is collectively shown in Tables 1 and 2.

(Evaluation methods)
(A) Transparency: The compositions of Examples 1 to 10 and Comparative Examples 1 to 7 were molded into a 1 mm thick plate, and the total light transmittance of this molded body was determined in accordance with JIS-K-7361-1. Was measured.
○: Total light transmittance of 60% or more.
X: The thing of less than 60% of total light transmittance.
(B) Thermal stability (molding processability): 65 g of each of the compositions of Examples 1 to 10 and Comparative Examples 1 to 7 were introduced into a laboratory plast mill tester manufactured by Toyo Seiki Co., Ltd., and the rotor rotation speed was 50 rpm. After kneading under a chamber temperature of 200 ° C., the time from when the vinyl chloride resin composition was introduced to when the torque showed rise due to decomposition was measured. The longer this time, the higher the thermal stability, and the determination was made according to the following criteria.
○: 10 minutes or more until the torque rise △: 8 minutes or more until the torque rise and less than 10 minutes ×: Less than 8 minutes until the torque rise (C) Flexible temperature: Crashberg flexible temperature according to JISK6734 for the obtained 1 mm thick molded plate Was measured, and the results were judged according to the following criteria.
○: Flexible temperature of 70 ° C. or higher Δ: Flexible temperature of 65 ° C. or higher and lower than 70 ° C. ×: Flexible temperature of lower than 65 ° C. (D) Impact resistance: About the obtained 1 mm-thick molded plate At 0 ° C, when dropping a 1 kg weight whose tip shape is eggplant-shaped, the height of the weight when the molded plate is destroyed by 50% is measured. Judged by.
○: Drop height at 50% breakage of 60 cm or more ×: Drop height at 50% breakage of less than 60 cm (E) Evaluation of appearance after molding: Visually observe the appearance of the obtained molded plate And determined according to the following criteria.
○: Surface smoothness is extremely excellent, and there is no unevenness, etc. Δ: Slightly marbling or fluffy surface roughness is generated on the surface, but there is no practical problem ×: Marbling on the surface Those that were not practical because of rough or burnt surface

The transparent vinyl chloride resin composition of the present invention has excellent transparency without requiring the addition of a dispersion aid in hard applications, and has excellent processability during molding (viscosity of melt, thermal stability, gel The molded product obtained using this resin composition has excellent impact resistance and appearance, maintains a high flexible temperature, and has good transparency. is there.
Since the molded article according to the present invention having such excellent characteristics has a total light transmittance of 60% or more, a softening temperature of 70 ° C. or more, and a 50% fracture height in a falling weight test of 60 cm or more, It is also suitable for outdoor use, and can be suitably used as a water supply / drainage pipe, plate, joint, corrugated plate and the like.

Claims (5)

A transparent vinyl chloride resin composition comprising 0.5 to 5 parts by weight of a stabilizer and 0.1 to 5 parts by weight of a lubricant with respect to 100 parts by weight of a vinyl chloride resin,
The stabilizer is a metal soap stabilizer;
Transparent vinyl chloride, wherein the lubricant is an acid value of 0.01 to 70 mg KOH / g, a density of 920 to 980 kg / m ³ , a modified polyethylene having a molecular weight of 900 to 8000, and / or a polypropylene having a molecular weight of 2000 to 20000. -Based resin composition.   Furthermore, the impact modifier is contained in an amount of 1 to 10 parts by weight, and the impact modifier is a chlorinated polyethylene having a chlorine content of 30 to 50% by weight and a refractive index of 1.50 to 1.55. 1. The transparent vinyl chloride resin composition according to 1.   The transparent vinyl chloride resin composition according to claim 2, wherein the lubricant is a polypropylene having a molecular weight of 2000 to 20000.   The stabilizer further comprises at least one of a methyltin compound and an octyltin compound in an amount of 0.1 to 50% by weight in the total amount with the metal soap stabilizer. 4. The transparent vinyl chloride resin composition according to any one of 3. A molded body obtained from the transparent vinyl chloride resin composition according to any one of claims 1 to 4,
Transparent chloride characterized in that the total light transmittance measured by JIS-K-7361-1 at a thickness of 1 mm of the molded body is 60% or more, and the softening temperature measured by the Crashberg method is 70 ° C. or more. Vinyl resin molding.