KR20190073862A - Polyvinyl chloride powder for powder slush molding and method for producing the same - Google Patents

Abstract

The present invention relates to polyvinyl chloride powder for powder slush molding and a method for producing the same. More particularly, the present invention relates to polyvinyl chloride powder for producing a skin material of a part for automobile interior parts including a skin material, a foam layer, and a base material from top to bottom by powder slush molding. The present invention relates to polyvinyl chloride powder for powder slush molding which is excellent in moldability while realizing a weight lightening effect by including a specific amount of a capsule type foaming agent; and a method for producing the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a polyvinyl chloride powder for powder slush molding and a method for producing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a polyvinyl chloride powder for powder slush molding and a method of manufacturing the same, and more particularly, to a polyvinyl chloride powder for powder slush molding, Foam layer; A polyvinyl chloride powder for producing the skin material of a vehicle interior material part including a carpet, a base material, and a powdered slush molding, wherein the encapsulated foaming agent is contained in a specific amount to provide a lightweight effect, Vinyl chloride powder and a process for producing the same.

Generally, Powder Slush Molding method has a higher degree of freedom of design and can keep the emboss pattern, compared with the conventional vacuum molding method, and is applied to the skin material of the instrument panel of a luxury automobile However, recently, it has been applied to small and medium-sized cars, and the applied parts are still being expanded from instrument panel to automobile interior parts such as gear box and door trim.

On the other hand, polyvinyl chloride resin (PVC), which is inexpensive and can be molded into various forms, is mainly used as a skin material of parts for automobile interior parts, as disclosed in Korean Patent Publication No. 10-2016-0148107, The vinyl resin had a specific gravity of about 1.2, which was too heavy.

In order to solve this problem, the inventors of the related art have attempted to realize lightening of the skin material by using a general chemical foaming agent such as azodicarbonamide on the skin material, but when applying the chemical foaming agent to the skin material, cell, and there is a problem that the design completeness of the surface emboss is very low.

KR 10-2016-0148107E (Dec. 26, 2016)

It is an object of the present invention to provide a polyvinyl chloride powder for powder slush molding having excellent moldability while realizing a weight reduction effect and a method for producing the same.

Another object of the present invention is to provide a skin material using the polyvinyl chloride powder for powder slush molding and a method for producing the skin material.

In order to achieve the above object,

The present invention relates to a core; And a shell enclosing the core surface, wherein the polyvinyl chloride powder is a polyvinyl chloride powder for powder slush molding,

Wherein the core comprises 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer and 0.7-10 parts by weight of a capsular foaming agent,

The shell provides 5 to 20 parts by weight of a paste polyvinyl chloride resin, and the polyvinyl chloride powder for powder slush molding.

In addition,

(a) 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer, and 0.7-10 parts by weight of a capsule type foaming agent are mixed in a Henschel mixer and mixed to form a core;

(b) forming a shell surrounding the core surface by putting the core of the above (a) and 5-20 parts by weight of a paste polyvinyl chloride resin into a cooling mixer, and then drying the polyvinyl chloride powder for powder slush molding Of the present invention.

In addition,

(a) 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer, and 0.7-10 parts by weight of a capsular foaming agent in a Banbury mixer and melting the mixture;

(b) preparing the mixture of step (a) in an extruder to form a pellet;

(c) pulverizing the pellet form of step (b) to form a core;

(d) adding a core of the step (c) and 5 to 20 parts by weight of a paste polyvinyl chloride resin to a cooling mixer to form a shell surrounding the core surface, the polyvinyl chloride for powder slush molding A method for producing a powder is provided.

The present invention also provides a skin material formed using polyvinyl chloride powder for powder slush molding of the present invention.

The present invention also provides a method for producing a skin material using the polyvinyl chloride powder for powder slush molding of the present invention.

The polyvinyl chloride powder for powder slush molding of the present invention has an excellent moldability.

In addition, the skin material formed from the polyvinyl chloride powder for powder slush molding of the present invention has an effect of reducing the weight of the conventional skin material.

Hereinafter, the polyvinyl chloride powder for powder slush molding of the present invention and a method for producing the same will be described in detail.

The present inventors have used a polyvinyl chloride resin and a chemical foaming agent together to solve the problem that a polyvinyl chloride resin is used as a skin material of automotive interior parts, which can not satisfy the weight saving effect due to its high specific gravity.

However, when the chemical foaming agent is foamed, an open cell is formed and holes are formed in the skin material. As a result, the inventors of the present invention have found that the chemical foaming agent is a capsule- It has been found that an open cell is not produced and a lightening effect is realized while having excellent moldability, and the present invention has been completed on the basis thereof.

The present invention relates to a core; And a shell enclosing the core surface, wherein the polyvinyl chloride powder is a polyvinyl chloride powder for powder slush molding,

Wherein the core comprises 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer and 0.7-10 parts by weight of a capsular foaming agent,

Wherein the shell comprises 5 to 20 parts by weight of a paste polyvinyl chloride resin.

Hereinafter, the polyvinyl chloride powder for powder slush molding of the present invention will be described in detail for each component.

A) Core

A-1) Straight polyvinyl chloride resin

The straight polyvinyl chloride resin contained in the core of the present invention may be one produced by suspension polymerization or bulk polymerization, and in this case, the transparency is excellent and the plasticizer absorption rate is fast.

As the straight polyvinyl chloride resin, for example, a straight polyvinyl chloride resin having a polymerization degree of 600-1800, or 800-1,700 may be used singly or a resin having a different degree of polymerization within the above range may be mixed.

If the degree of polymerization of the straight polyvinyl chloride resin is less than the above range, properties such as tensile strength, elongation at break and tear strength may not be satisfied. If the degree of polymerization is higher than the above range, molding temperature of the molded article becomes higher, It may be within the above range.

The pores of the straight polyvinyl chloride resin may be, for example, 25-50% or 30-40%. If the amount is less than the above range, oil absorption of the plasticizer in the straight polyvinyl chloride resin is lowered, and if it exceeds the above range, it is difficult to produce the straight polyvinyl chloride resin.

The voids can be measured through a CPA (Cold Plasticizer Absorption) value, and the CPA can be measured according to ASTM D2396 and / or ISO 4574.

More specifically, the CPA may be an amount of the plasticizer that is absorbed into the polyvinyl chloride resin at 20 ° C in terms of% by weight based on the polyvinyl chloride resin before the plasticizer absorption.

A-2) Plasticizer

The plasticizer may be at least one selected from low-molecular plasticizers and high-molecular plasticizers.

In the present invention, the low molecular weight plasticizer may be defined as a plasticizer having a molecular weight of 300 g / mole to 1500 g / mole.

Examples of the low molecular weight plasticizers include phthalate plasticizers, terephthalate plasticizers, benzoate plasticizers, citrate plasticizers, phosphate plasticizers, adipate plasticizers, glycol plasticizers, epoxy plasticizers, and trimellitate plasticizers. May be at least one selected from the group consisting of

Examples of the phthalate plasticizer include diethyl phthalate, diisononyl phthalate, diisodecyl phthalate, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, dinonyl phthalate and ditridecyl phthalate But are not limited thereto.

As the terephthalate plasticizer, dioctyl terephthalate may be used, but is not limited thereto.

Examples of the benzoate plasticizer include 2- (2- (2-phenylcarbonyloxyethoxy) ethoxy) ethylbenzoate, glyceryl tribenzoate, trimethylolpropane tribenzoate, isononyl benzoate, 1- Methyl-2- (2-phenylcarbonyloxypropoxy) ethylbenzoate, 2,2,4-trimethyl-1,3-pentanediol dibenzoate, n-hexylbenzoate and trimethylolpropane tribenzoate But is not limited thereto.

The citrate plasticizer may be, for example, at least one selected from the group consisting of acetyl tributyl citrate, tributyl citrate, acetyl triethyl hexyl citrate, and triethyl hexyl citrate, but is not limited thereto.

The phosphate plasticizer may be, for example, at least one selected from the group consisting of tricresyl phosphate and tributyl phosphate, but is not limited thereto.

The adipate plasticizer may be, for example, at least one selected from the group consisting of bis (2-ethylhexyl) adipate, dimethyl adipate, monomethyl adipate and dioctyl adipate diisononyl adipate, It is not.

The glycol-based plasticizer may be, for example, at least one selected from the group consisting of ethylene glycol and propylene glycol, but is not limited thereto.

As the epoxy plasticizer, for example, epoxidized soybean oil may be used, but it is not limited thereto.

The trimellitate plasticizer may be selected from the group consisting of triisobutyl trimellitate, trinormal octyl trimellitate, tri (2-ethylhexyl) trimellitate, trioctyl trimellitate and triisononyl trimellitate But the present invention is not limited thereto.

In the present invention, the low molecular weight plasticizer may preferably be a trimellitate plasticizer that is environmentally friendly, has excellent thermal stability and can improve the anti-planarity of the plasticizer.

When the low molecular weight plasticizer is used, the physical properties of the skin material are excellent, and plasticizer penetration into the polyvinyl chloride resin is easy, and sufficient flexibility can be imparted.

In the present invention, the polymer plasticizer may be defined as a plasticizer having a weight average molecular weight of 1,500 to 450,000 g / mole.

In the present invention, the weight average molecular weight can be measured by using Gel Permeation Chromatography (GPC).

The polymer plasticizer may be, for example, a polyester plasticizer or a ternary copolymer resin of ethylene-vinyl acetate, vinyl ether or alkyl acrylate-carbon monoxide.

Examples of the polyester plasticizer include at least one selected from the group consisting of poly-2-ethylhexyl glycol adipate, adipic acid polyester, citric acid polyester, sebacic acid polyester, azelaic acid polyester and phthalic acid polyester . ≪ / RTI >

Preferably, the polyester plasticizer may have a weight average molecular weight of 1,500 to 6,000 g / mole. When the weight average molecular weight is less than the above range, the polyester plasticizer does not exhibit anti-migration properties as a polymer plasticizer. The workability in the process of compounding with the straight polyvinyl chloride resin is lowered, so that it can be within the above range.

The alkyl acrylate in the terpolymer resin may be at least one selected from the group consisting of methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec- , Methyl butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, pentadecyl acrylate, dodecyl acrylate, isobornyl acrylate, At least one selected from the group consisting of phenylacrylate, benzyl acrylate, phenoxyethyl acrylate, 2-hydroxyethyl acrylate, 2-methoxyethyl acrylate, glycidyl acrylate and allyl acrylate can be used have.

The content of ethylene in the terpolymer resin is 50-80% by weight, or 60-75% by weight; The content of vinyl acetate, vinyl ether or alkyl acrylate is 15-40% by weight, or 20-35% by weight; The content of the carbon monoxide may be 4-20 wt%, or 5-13 wt%.

If the ethylene content is less than the above range, the stiffness of the ternary copolymer resin may be deteriorated. If the ethylene content is in excess of the above range, the adhesive strength between the skin material and the foam layer may be lowered.

When the amount of the carbon monoxide is less than the above range, the compatibility with the straight polyvinyl chloride resin is lowered. If the content of the carbon monoxide exceeds the above range, the content of ethylene and alkyl acrylate may be relatively decreased and the rigidity of the resin may be lowered. .

The weight average molecular weight of the ternary copolymer resin may be 250,000-400,000 g / mole. If the weight average molecular weight is less than the above range, the ternary copolymer resin may not exhibit anti-migration properties as a polymer plasticizer. The workability in the process of compounding with the straight polyvinyl chloride resin is lowered, so that it can be within the above range.

When the polymer plasticizer is used, the plasticizer in the skin material is not transferred to the foam layer, so that the physical properties of the skin material can be excellent.

The plasticizer may be used in an amount of 60-120 parts by weight, or 70-110 parts by weight, based on 100 parts by weight of the straight polyvinyl chloride resin. If the amount is less than the above range, sufficient flexibility can not be imparted to the straight polyvinyl chloride resin, and if it exceeds the above range, physical properties of the skin material may be deteriorated and migration of the plasticizer may occur. .

A-3) Capsule type foaming agent

The capsular foaming agent contained in the core of the present invention may be a thermally expandable microcapsule containing an outer shell of a resin material and a foaming agent contained in the outer shell and having a boiling point below the softening point of the resin used for the outer shell.

More specifically, when the heat of the appropriate temperature is applied to the capsular foaming agent, softening of the outer shell starts, and at the same time, the foaming agent contained in the outer vessel is vaporized to increase the internal pressure, thereby expanding the capsular foaming agent.

The outer frame may be at least one thermoplastic resin selected from the group consisting of an acrylonitrile copolymer, a vinylidene chloride copolymer, polyethylene, polypropylene, and polystyrene, but is not limited thereto.

The blowing agent may be at least one liquid hydrocarbon selected from the group consisting of propane, propylene, butene, butane, isobutane, isopentane, neopentane, n-pentane, normal hexane, isohexane, heptane, have.

The capsule type foaming agent may have a particle size of 7-50 탆 or 10-30 탆, for example. When the amount is less than the above range, sufficient foam can not be obtained. When the amount exceeds the above range, the particle size of the foamed cell (air bubble) to be formed becomes large and the strength required as a skin material of automotive interior parts is lowered. have.

In the present invention, the particle size can be measured using a scanning electron microscope (SEM) or the like.

For example, the encapsulated foaming agent may have an expansion starting temperature of 150-190 ° C or 155-180 ° C. When the amount is less than the above range, it is difficult to realize sufficient foam molding effect at the molding temperature at which the powder is already foamed during the polyvinyl chloride powder production process and the powder slush molding process is carried out. Therefore, the expansion starting temperature may be within the above range.

The expansion starting temperature means a temperature when the displacement in the height direction changes to positive when the capsule type foaming agent is heated by a thermomechanical analyzer (TMA).

The capsular foaming agent may have a maximum expansion temperature of 200-250 ° C or 210-250 ° C, for example. If it is less than the above range, the size of the foamed cell becomes small at the molding temperature at which the powder slush molding process of the present invention is carried out. As a result, sufficient foam molding effect can not be realized. If the range is exceeded, the powder slush molding process of the present invention Since the foaming does not occur at the molding temperature, the effect of lighter weight of the skin material of the automobile interior parts can not be realized, so that the maximum expansion temperature can be obtained in the temperature range.

The maximum expansion temperature means the temperature at which the capsule type foaming agent becomes the maximum displacement amount when the diameter of the capsule type foaming agent is measured while heating the capsule type foaming agent from the room temperature by a thermomechanical analyzer (TMA).

The capsule type foaming agent may be used in an amount of 0.7-10 parts by weight or 1-7 parts by weight based on 100 parts by weight of the straight polyvinyl chloride resin. If the amount is less than the above range, the effect of lightening the skin material of the automobile interior parts is insignificant, and if it exceeds the above range, the moldability is deteriorated.

The core of the present invention may optionally further comprise at least one additive selected from the group consisting of a high heat stabilizer, a lubricant, an antioxidant, a light stabilizer, a heat resisting agent, a flame retardant and an antistatic agent.

The additive may be of a conventional kind used in the art, and therefore the kind and content of the additive are not particularly limited in the present invention.

For example, the additive may be 0.1-10 parts by weight or 1-8 parts by weight based on 100 parts by weight of the straight polyvinyl chloride resin.

B) Shell

The shell of the present invention encapsulates the above-described core to prevent entanglement between grains and plays an important role in future molding.

The shell may be formed to a thickness of 0.1-20 mu m or 0.5-10 mu m. If the thickness of the shell is less than the above range, the dropping of the polyvinyl chloride powder may be deteriorated, and if the thickness of the shell exceeds the above range, the moldability is deteriorated.

B-1) Paste (paste) polyvinyl chloride resin

The paste polyvinyl chloride resin contained in the shell can be produced by emulsion polymerization, and in this case, there is an effect of excellent viscosity stability and foamability.

As the paste polyvinyl chloride resin, for example, a paste polyvinyl chloride resin having a degree of polymerization of 600 to 1500 or 800 to 1300 may be used alone or in combination with resins having different degrees of polymerization within the above range.

When the polymerization degree of the paste polyvinyl chloride resin is less than the above range, the yield may be lowered during the dry blending process. If the polymerization degree exceeds the above range, the molding temperature of the molded product may increase, .

The particle size of the paste polyvinyl chloride resin may be, for example, 0.1-20 mu m or 0.3-10 mu m. If the amount is less than the above range, the polyvinyl chloride powder may fall off and the powder slush molding process may be difficult, and if it exceeds the above range, it may be dispersed in a form that does not wrap the core surface.

The paste polyvinyl chloride resin may be used in an amount of 5-20 parts by weight, or 5-15 parts by weight, based on 100 parts by weight of the polyvinyl chloride resin contained in the core to form a shell. If the amount is less than the above range, it is difficult to form a polyvinyl chloride core / shell structure, so that the castability of the powder is lowered and the molding process becomes difficult. When the amount exceeds the above range, the amount of the plastic polyvinyl chloride resin And the physical properties of the skin material deteriorate. Therefore, it is preferable that the content is within the above range.

The particle size of the polyvinyl chloride powder for powder slush molding of the present invention may be 100-350 占 퐉 or 150-250 占 퐉. If the amount is less than the above range, the polyvinyl chloride powder may fall hard to be cast, and the powder slush molding process may be difficult. If the above range is exceeded, the polyvinyl chloride powder may hardly melt in a short time, Lt; / RTI >

Hereinafter, a method for producing polyvinyl chloride powder for powder slush molding according to the present invention will be described in detail.

The method for producing polyvinyl chloride powder for powder slush molding according to the present invention comprises

(a) 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer, and 0.7-10 parts by weight of a capsule type foaming agent are mixed in a Henschel mixer and mixed to form a core;

(b) placing the core of (a) and 5-20 parts by weight of the paste polyvinyl chloride resin in a cooling mixer to form a shell surrounding the core surface.

Since the straight polyvinyl chloride resin and the capsule type foaming agent in the step (a) are the same as those described above, the overlapping description is omitted.

In the step (a), the low molecular weight plasticizer described above may be used as the plasticizer.

More specifically, in a Henschel mixer, a polymer plasticizer having a weight average molecular weight of 1,500 to 450,000 g / mole is not absorbed into the straight polyvinyl chloride resin, so that flexibility can not be imparted to the core and moldability is deteriorated. Molecular weight plasticizer having a molecular weight of from 300 g / mole to less than 1500 g / mole can be used.

In the step (a), it is preferable that the mixing is carried out in a Henschel mixer for 60 to 120 minutes without heating. At this time, the temperature of the mixture may rise to about 120 DEG C due to the frictional heat, and mixing is performed by the time, thereby making it possible to increase the oil absorption of the low molecular weight plasticizer in the straight polyvinyl chloride resin through sufficient blending.

In the step (a), one or more additives selected from the group consisting of a high heat stabilizer, a lubricant, an antioxidant, a light stabilizer, a heat resistant agent, a flame retardant and an antistatic agent may be further added to a Henschel mixer.

Since the kind and content of the additive are the same as those described above, the overlapping description is omitted.

In the step (b), the core produced in the step (a) is put into a cooling mixer together with an emulsion paste polyvinyl chloride resin and then shaken to form a shell surrounding the core surface to form a core / It may be a step of producing a polyvinyl chloride powder.

Alternatively, the method for producing the polyvinyl chloride powder for powder slush molding of the present invention

(a) 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer, and 0.7-10 parts by weight of a capsular foaming agent in a Banbury mixer and melting the mixture;

(b) preparing the mixture of step (a) in an extruder to form a pellet;

(c) pulverizing the pellet form of step (b) to form a core;

(d) placing a core of the step (c) and 5-20 parts by weight of a paste polyvinyl chloride resin into a cooling mixer to form a shell surrounding the core surface.

Since the straight polyvinyl chloride resin and the capsule type foaming agent in the step (a) are the same as those described above, the overlapping description is omitted.

In the step (a), the plasticizer may be at least one selected from a low-molecular plasticizer and a high-molecular plasticizer, and preferably a low-molecular plasticizer and a high-molecular plasticizer may be mixed.

When the polymeric plasticizer and the low molecular weight plasticizer are mixed and used, the plasticizer efficiency and moldability are superior to those when the polymeric plasticizer is used alone.

More specifically, since the polymeric plasticizer having a weight average molecular weight of 1,500 to 450,000 g / mole is melted in a Banbury mixer to plasticize the straight polyvinyl chloride resin, a polymer plasticizer is used as the plasticizer of the step (a) .

In the step (a), one or more additives selected from the group consisting of a high heat stabilizer, a lubricant, an antioxidant, a light stabilizer, a heat resisting agent, a flame retardant and an antistatic agent may be further added to a Banbury mixer.

Since the kind and content of the additive are the same as those described above, the overlapping description is omitted.

The step (a) may be performed in a Banbury mixer so that the straight polyvinyl chloride resin and the polymer plasticizer are kneaded well, and the mixture is melted at 100-140 ° C or 120-130 ° C for 40-120 minutes. have.

When the polyvinyl chloride resin is melted at a temperature lower than the above-mentioned time and temperature range, the polyvinyl chloride resin is insoluble and insufficient to be sufficiently kneaded with the plasticizer. When the polyvinyl chloride resin is melted in excess of the time and temperature range, Deterioration of the vinyl chloride resin may occur, and the resin may be melted within the time and temperature range.

In the step (b), the mixture melted in the step (a) may be pelletized through an extruder.

In the step (c), the pellet produced in the step (b) is frozen at 50 ° C using liquid nitrogen and then pulverized or pulverized by hydro-grinding to form a core into fine particles having a diameter of 350 μm or less Lt; / RTI >

In the step (d), the core prepared in the step (c) is put into a mixer together with an emulsion paste polyvinyl chloride resin and then shaken to form a shell surrounding the core surface to form a core / shell structure polyvinyl chloride powder Can be a manufacturing step.

The polyvinyl chloride powder for powder slush molding of the present invention has an excellent moldability.

The present invention also relates to a skin material formed using the polyvinyl chloride powder for powder slush molding.

The skin material may be, for example, a skin material for parts for automobile interior materials.

The automotive interior parts may be instrument panel, door trim, dashboard, console box, armrest, headrest, filler trim, seat buckle, headliner, glove box trunk cover trim, airbag cover or steering wheel cover.

The manufacturing method of the skin material using the powder slush molding method is as follows.

First, a mold heated at about 200-250 캜 and an open container (powder box) loaded with the polyvinyl chloride powder are combined to form a closed system, and then the mold is rotated to form a skin material. At this time, the capsular foaming agent in the polyvinyl chloride powder is firstly foamed.

Next, after separating the combined metal mold and the open container (powder box), the polyvinyl chloride powder is melted to a less extent on the opposite side of the metal mold, so that the molded polyvinyl chloride powder The capsular foaming agent in the container is secondarily foamed.

Thereafter, after the mold is cooled, the molded skin material from the mold is demolded.

The capsular foaming agent may be foamed at 200-250 ° C or at 210-230 ° C. When the amount is less than the above range, sufficient foaming cells (bubbles) can not be obtained, the effect of lightening the skin material of the automobile interior parts is insignificant and the formability is deteriorated. When the above range is exceeded, It is impossible to obtain a foam cell having a sufficient size and the effect of lightening the skin material of the automobile interior parts is insignificant, so that the foam can be foamed within the above temperature range.

In addition, the skin material formed from the polyvinyl chloride powder for powder slush molding of the present invention has an effect of reducing the weight of the conventional skin material.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention. Such variations and modifications are intended to be within the scope of the appended claims.

[Example]

The compositions used in the following Examples and Comparative Examples are as follows.

- Straight polyvinyl chloride resin: A polyvinyl chloride resin with a degree of polymerization of 1300 was used (LG Chem, LS130S).

- Low molecular weight plasticizer: Trioctyl trimellitate (TOTM) having a molecular weight of 550 g / mole was used (LG Chem, TOTM).

-Polymer plasticizer: A ternary copolymer resin containing ethylene, vinyl ether or carbon monoxide having a weight average molecular weight of 400,000 g / mole was used (Dupont, Elvaloy).

- Capsule type foaming agent: Thermally expandable microcapsules having a particle size of 10-15 탆, an expansion starting temperature of 155-165 캜 and a maximum expansion temperature of 210-220 캜 (Matsumoto, FN-190SSD) were used.

- High heat stabilizer: Ba-Zn high heat stabilizer was used.

- Light stabilizer: Benzophenone light stabilizer was used.

- Paste polyvinyl chloride resin: A polyvinyl chloride resin with a degree of polymerization of 900 and a particle size of 0.5-2 탆 was used (LG Chemical, LP090).

- Chemical foaming agent: Azodicarbonamide (ADCA) was used.

[Example]

1. Epoxy material manufacturing of automobile interior parts parts using polyvinyl chloride powder for powder slush molding

(1) Production of polyvinyl chloride powder for powder slush molding

≪ Example 1 >

100 parts by weight of a straight polyvinyl chloride resin, 80 parts by weight of a low molecular weight plasticizer, 2 parts by weight of a capsule type foaming agent, 6 parts by weight of a high heat stabilizer and 0.3 parts by weight of a light stabilizer were mixed and mixed in a Henschel mixer to form a core.

Next, 10 parts by weight of the core and the paste vinyl chloride resin were placed in a cooling mixer to form a shell surrounding the core surface, thereby preparing a polyvinyl chloride powder for core / shell structure powder slush molding.

≪ Example 2 >

Polyvinyl chloride powder for powder slush molding was prepared in the same manner as in Example 1 except that 5 parts by weight of the encapsulated foaming agent was used.

≪ Comparative Example 1 &

Polyvinyl chloride powder for powder slush molding was prepared in the same manner as in Example 1, except that 15 parts by weight of the encapsulated foaming agent was used.

≪ Comparative Example 2 &

Polyvinyl chloride powder for powder slush molding was prepared in the same manner as in Example 1 except that 0.5 parts by weight of the encapsulated foaming agent was used.

≪ Comparative Example 3 &

A polyvinyl chloride powder for powder slush molding was prepared in the same manner as in Example 1, except that the encapsulated foaming agent was not used.

(2) Manufacture of skin materials for automobile interior parts

Using the polyvinyl chloride powders of Examples 1-2 and 1-3 prepared in the above (1), the skin material of automobile interior parts was manufactured by the powder-slush molding method.

At this time, the capsular foaming agent was foamed at a molding temperature of 220 캜 (mold temperature).

≪ Comparative Example 4 &

Except that 2 parts by weight of a chemical foaming agent (azodicarbonamide, ADCA) which is not the capsule-type foaming agent was used, to prepare a skin material for automobile interior parts.

≪ Reference Example 1 &

A skin material for automobile interior parts was manufactured in the same manner as in Example 1, except that the capsule type foaming agent of Example 1 was foamed at a molding temperature of 260 캜.

≪ Reference Example 2 &

A skin material for automobile interior parts was manufactured in the same manner as in Example 1, except that the capsule type foaming agent of Example 1 was foamed at a molding temperature of 180 캜.

[ Test Example ]

The specific gravity, formability and open cell presence / absence of the skin materials of the automotive interior parts of Example 1-2, Comparative Examples 1-4 and Reference Example 1-2 prepared in the above (2) were measured, The results are shown in Table 1 below.

- The specific gravity was measured using a digital electronic gravimeter (ALFA MIRAGE, MD300S).

- The formability was measured visually.

(○: No problem of moldability on front / rear of skin surface

Δ: There is a fine pinhole on the surface of the skin.

X: There is an open cell on the front surface of the skin or a powder that is not completely dissolved on the back)

- The open cells were measured visually.

Foaming temperature
(° C) Capsule foaming agent Chemical foaming agent
(Parts by weight) importance Formability Open cell
The presence or absence content
(Parts by weight) Particle size
(탆) Example 1 220 2 10 - 1.00 ○ radish Example 2 220 5 10 - 0.82 ○ radish Comparative Example 1 220 15 10 - 0.52 Δ radish Comparative Example 2 220 0.5 10 - 1.15 ○ radish Comparative Example 3 - - - - 1.20 ○ radish Comparative Example 4 220 - - 2 0.80 X U Reference Example 1 260 2 10 - 1.08 ○ radish Reference Example 2 180 2 10 - 1.12 X radish

As shown in Table 1, Examples 1 and 2, which are the skin materials produced using the polyvinyl chloride powder for powder slush molding of the present invention, are low in specific gravity and excellent in lightening effect, do not have open cells, .

On the other hand, Comparative Example 3 in which the polyvinyl chloride powder for powder slush molding was not foamed had a high specific gravity and the lightening effect was inferior. In Comparative Example 4, which was foamed using a chemical foaming agent rather than a capillary type foaming agent, an open cell was formed And it was confirmed that the moldability was not good.

In addition, Comparative Example 2 containing the capsule-like foaming agent at a specific content of less than the specified content had a high specific gravity, which was inferior in lighter weight, and Comparative Example 1 containing a specific content exceeded a certain amount, indicating that the formability was lowered as compared with the embodiment of the present invention.

In addition, in the case of Reference Example 1 in which the capsule type foaming agent was foamed at a higher molding temperature than the examples of the present invention, the size of the foamed cells was smaller, and the specific gravity was higher than that of the examples of the present invention, there was.

In addition, in the case of Reference Example 2 in which the capsule-type foaming agent was foamed at a lower molding temperature than that of the examples of the present invention, it was confirmed that foaming occurred less and the specific gravity was high and the formability was also lowered.

Claims (16)

core; And a shell enclosing the core surface, wherein the polyvinyl chloride powder is a polyvinyl chloride powder for powder slush molding,
Wherein the core comprises 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer and 0.7-10 parts by weight of a capsular foaming agent,
Wherein the shell comprises 5 to 20 parts by weight of a paste polyvinyl chloride resin. The method according to claim 1,
Wherein the plasticizer is at least one selected from a low-molecular plasticizer and a high-molecular plasticizer. 3. The method of claim 2,
The low molecular weight plasticizer has a molecular weight of 300 g / mole or more and less than 1,500 g / mole,
Wherein the polymer plasticizer is a plasticizer having a weight average molecular weight of 1,500 to 450,000 g / mole. The method according to claim 1,
Wherein the encapsulated foaming agent is a thermally expandable microcapsule comprising an outer shell made of a resin material and a foaming agent contained in the outer shell and having a boiling point below the softening point of the resin used for the outer shell. 5. The method of claim 4,
Wherein the outer surface is at least one thermoplastic resin selected from the group consisting of an acrylonitrile copolymer, a vinylidene chloride copolymer, polyethylene, polypropylene, and polystyrene. 5. The method of claim 4,
The blowing agent is at least one liquid hydrocarbon selected from the group consisting of propane, propylene, butene, butane, isobutane, isopentane, neopentane, n-pentane, n-hexane, isohexane, heptane, Polyvinyl chloride powder for powder slush molding. The method according to claim 1,
Wherein the capsule-type foaming agent has a particle size of 7-50 mu m. The method according to claim 1,
Wherein the capsular foaming agent has an expansion starting temperature of 150 to 190 DEG C. The method according to claim 1,
Wherein the capsular foaming agent has a maximum expansion temperature of 200 to 250 ° C. (a) 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer, and 0.7-10 parts by weight of a capsule type foaming agent are mixed in a Henschel mixer and mixed to form a core;
(b) forming a shell surrounding the core surface by putting the core of the above (a) and 5-20 parts by weight of the paste polyvinyl chloride resin into a cooling mixer to form a polyvinyl chloride powder for powder slush molding. 11. The method of claim 10,
Wherein the plasticizer of step (a) is a low molecular weight plasticizer having a molecular weight of 300 g / mole or more and less than 1,500 g / mole. 11. The method of claim 10,
Wherein the mixing of step (a) is performed in a Henschel mixer and the mixture is rotated without heating for 60 to 120 minutes. (a) 100 parts by weight of a straight polyvinyl chloride resin, 60-120 parts by weight of a plasticizer, and 0.7-10 parts by weight of a capsular foaming agent in a Banbury mixer and melting the mixture;
(b) preparing the mixture of step (a) in an extruder to form a pellet;
(c) pulverizing the pellet form of step (b) to form a core;
(d) adding a core of the step (c) and 5 to 20 parts by weight of a paste polyvinyl chloride resin to a cooling mixer to form a shell surrounding the core surface, the polyvinyl chloride for powder slush molding Powder. 14. The method of claim 13,
Wherein the plasticizer used in the step (a) is at least one selected from the group consisting of a low-molecular plasticizer and a high-molecular plasticizer. A skin material for parts for automobile interior parts formed by using the polyvinyl chloride powder for powder slush molding according to any one of claims 1 to 9. A method for manufacturing a skin material for automobile interior parts, wherein the polyvinyl chloride powder for powder slush molding according to any one of claims 1 to 9 is foamed at 200-250 占 폚.