KR100868881B1 - Thermoplastic Resin Having Improved Scratch Resistance and Method for Preparing Same - Google Patents

Abstract

The method for preparing a thermoplastic resin having excellent scratch resistance according to the present invention comprises mixing aqueous dispersed colloidal nanoparticles with alcohol and ion-exchanged water, and adding an alkoxy silane compound to the aqueous dispersed colloidal nanoparticles from 5 to 25. Preparing a colloidal nanoparticle in which a lipophilic vinyl group is introduced to the surface by a dropwise addition by weight; And suspending polymerizing the colloidal nanoparticles into which the lipophilic vinyl group is introduced to the surface with an acrylic monomer.

Colloidal Nanoparticles, Lipophilic, Acrylic Resin, Suspension Polymerization, Scratch, Transparency, Flowability

Description

Thermoplastic Resin Having Improved Scratch Resistance and Method for Preparing Same}

Field of invention

The present invention relates to a thermoplastic resin having excellent scratch resistance. More specifically, the present invention relates to a thermoplastic resin having excellent scratch resistance and transparency by preparing and polymerizing a lipophilic colloidal nanoparticle having a vinyl group using an alkoxy silane compound in the colloidal nanoparticle. The present invention includes thermoplastic resins excellent in scratch resistance and transparency.

Background of the Invention

In general, thermoplastic resins have excellent injection moldability and excellent physical balance, and thus are widely used as housing materials for electrical, electronic parts, and office equipment. However, with the rise of high-end home appliances such as LCD, PDP TV, and audio, efforts are being made to express high-quality texture in injection molded products and to reduce scratches, that is, excellent scratch resistance.

As a conventional method for improving the scratch resistance, high-quality texture is expressed by using a method such as coating urethane or the like on the surface of the injection molded product, UV coating treatment, or coating an acrylic product having excellent scratch resistance. There is a method to improve scratch resistance. However, this is an operation in which post-processing is added, accompanied by an increase in cost, an increase in defective rate, a problem in lowering productivity, and an environmental inhibition problem due to painting.

Another conventional method for imparting high quality texture and scratch resistance of an injection molded product is to use an acrylic resin as a material for injection molding. Generally, acrylic resins have excellent transparency and surface gloss, so that coloring to an advanced texture is difficult. It is easy to use, and has excellent scratch resistance, high stiffness and weather resistance, and is suitable for improving high quality texture and scratch resistance.

On the other hand, in order to exhibit high functionality of the thermoplastic resin, the development of a thermoplastic composite using an inorganic material having a low coefficient of thermal expansion and excellent wear resistance and rigidity as a composite material is increasing.

In general, inorganic materials for improving physical properties of the thermoplastic resin are glass fiber, carbon fiber, talc, and the like, and the strength of the resin may be increased by blending them with the thermoplastic resin. However, it is difficult to secure dispersibility due to the lack of bonding strength between inorganic materials and resins and lack of affinity between different types of resins. Therefore, a large amount of inorganic materials must be used to observe the effect of increasing physical properties over a certain level. Side effects occur, which implies that it is difficult to express high quality texture.

Recently, with the development of nanotechnology, researches on polymers including inorganic nanoparticles have been actively conducted. By adding a small amount of inorganic nanoparticles to a polymer material, the performance of the polymer resin can be improved.

The uniform dispersion of the inorganic nanoparticles in the resin is a very important factor in preparing the resin in which the inorganic nanoparticles are composited, because the variation of physical properties according to the dispersion degree is very large even with the same inorganic nanoparticle content. In the case of inorganic nanoparticles, when they come into contact with heterogeneous organic substances, the dispersion stability rapidly decreases and aggregates together. A study to improve dispersion stability of inorganic nanoparticles in a polymer resin is a major task of preparing organic-inorganic nanoparticle composites. Can be.

Accordingly, the present inventors propose a method of preparing a thermoplastic resin in which inorganic nanoparticles are evenly dispersed in a polymer resin by introducing a lipophilic functional group and increasing the dispersion stability of the inorganic nanoparticles into a thermoplastic resin polymerization process. More specifically, by copolymerizing an acrylic monomer in the presence of a lipophilic colloidal nanoparticle containing a vinyl group, it is to develop a method for producing a thermoplastic acrylic resin of nanoparticle composite with improved scratch resistance while maintaining transparency and resin properties.

An object of the present invention is to provide a method for producing a thermoplastic resin excellent in scratch resistance.

Another object of the present invention is to provide a method for producing a thermoplastic resin having excellent scratch resistance and excellent transparency.

Still another object of the present invention is to provide a thermoplastic resin having excellent scratch resistance and excellent transparency.

The above and other objects of the present invention can be achieved by the present invention described below.

Summary of the Invention

The method for preparing a thermoplastic resin having excellent scratch resistance according to the present invention comprises mixing aqueous dispersed colloidal nanoparticles with alcohol and ion-exchanged water, and adding an alkoxy silane compound to the aqueous dispersed colloidal nanoparticles from 5 to 25. Preparing a colloidal nanoparticle in which a lipophilic vinyl group is introduced to the surface by a dropwise addition by weight; And

Suspending polymerization of the colloidal nanoparticles in which a lipophilic vinyl group is introduced to the surface with an acrylic monomer.

It is preferable that the colloidal nanoparticles have a diameter of 5 to 50 nm in terms of improving transparency.

The aqueous dispersed colloidal nanoparticles are preferably used in 1 to 15 parts by weight.

It is preferable that methyl methacrylate is used for the said acryl-type monomer.

In the step of suspension polymerization, a monomer copolymerizable with an acrylic monomer may be added, but the content of the acrylic monomer may be 50% by weight or more based on the total monomer mixture, and may be suspension polymerization. In this case, the monomer copolymerizable with the acrylic monomer is ethyl methacrylate, propyl methacrylate, butyl methacrylate, phenyl methacrylate, benzyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acryl Preference is given to at least one monomer selected from the group consisting of late and 2-ethylhexyl acrylate.

Octane oil peroxide, decanyl peroxide, lauroyl peroxide, benzoyl peroxide, monochlorobenzoyl peroxide, dichlorobenzoyl peroxide, para methylbenzoyl peroxide, tertiary butyl peroxide as polymerization initiator in the suspension polymerization step At least one polymerization initiator selected from the group consisting of benzoate, azobisisobutyronitrile and azobis- (2,4-dimethyl) -valeronitrile may be added.

At least one alkyl mercaptan selected from the group consisting of normal butyl mercaptan, normal octyl mercaptan, normal dodecyl mercaptan, tertiary dodecyl mercaptan, isopropyl mercaptan and normal amyl mercaptan as molecular weight modifiers in the suspension polymerization step You can also use

In the suspension polymerization step, a suspension stabilizer of a metal phosphate series selected from the group consisting of tricalcium phosphate and trisodium phosphate may be used as a suspension stabilizer or a suspension stabilizer of a homopolymer of acrylic acid or methacrylic acid.

The present invention includes a thermoplastic resin having excellent scratch resistance produced by the above production method.

Hereinafter, the content of the present invention will be described in detail.

Detailed Description of the Invention

The thermoplastic resin manufacturing method of the present invention is to prepare a nanoparticle composite thermoplastic resin, the first step of preparing colloidal nanoparticles in which a lipophilic vinyl group is introduced to the surface by reacting the aqueous dispersed colloidal nanoparticles with an alkoxy silane compound; And suspending the colloidal nanoparticles into which the lipophilic vinyl group is introduced and the acrylic monomer together.

Preparation of Colloidal Nanoparticles Introduced by Lipophilic Vinyl Group

First, in order to introduce a lipophilic vinyl group onto the surface of the colloidal nanoparticles, the aqueous dispersion of the colloidal nanoparticles is added to the alcohol and the ion-exchanged water and stirred to be diluted. The alkoxy silane compound is added to the colloid dilution solution prepared above through an appropriate dropping device, and stirred using an electric stirrer. When the addition of the alkoxy silane compound is completed, a nanoparticle composite thermoplastic resin is prepared by removing alcohol produced through a hydration reaction using a vacuum apparatus at a temperature of 60 ° C. After the removal of the alcohol byproduct is completed, the temperature is raised to about 80 ° C., followed by 2 h of stirring to minimize the remaining unreacted product. After the reaction is completed, the reactor is cooled to room temperature to prepare colloidal nanoparticles having a lipophilic vinyl group introduced on the nanoparticle surface.

Preferably, the aqueous dispersed colloidal nanoparticles may be used in the range of 1 to 15 parts by weight, 2 to 10 parts by weight of alcohol to be mixed, and 2 to 10 parts by weight of ion exchanged water.

 The alkoxy silane compound is preferably used in the range of 5 to 25% by weight, that is, 0.05 to 6 parts by weight based on the weight of the aqueous dispersed colloidal nanoparticles.

The aqueous dispersed colloidal nanoparticles of the present invention are colloidal metal oxides or metals such as silicon dioxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), titanium oxide (TiO ₂ ), tin oxide (SnO ₂ ), iron oxide ( Fe ₂ O ₃ ), zinc oxide (ZnO), magnesium oxide (MgO), zirconium oxide (ZrO ₂ ), cerium oxide (CeO ₂ ), lithium oxide (Li ₂ O), silver oxide (AgO) metal oxides and silver (Ag), nickel (Ni), magnesium (Mg), zinc (Zn) and the like can be selected from the group consisting of pure metals and mixtures thereof. Preferably, silicon dioxide (SiO ₂ ) which is inexpensive but does not have side effects such as polymer decomposition is used.

In the present invention, the size of the aqueous dispersed colloidal nanoparticles may be used in the range of 5 to 300 nm, and in order not to affect transparency, it is preferable to use spherical particles of 5 to 50 nm.

The alkoxy silane compound contains at least one hydrolyzable silane moiety and an organic moiety having a vinyl group other than the silane moiety, and includes acryloxyalkyl trimethoxysilane, methacryloxyalkyl trimethoxysilane, and methacrylicoxyalkyl trie. One or more components selected from oxysilane, vinyl trimethoxysilane and vinyl triethoxysilane can be used. Preferably, it is preferable to use methacryloxyalkyl trimethoxysilane which is inexpensive and excellent in reactivity with the acrylic monomer.

The reason for introducing the alkoxy silane compound on the surface of the colloidal nanoparticles is to introduce a lipophilic functional group on the surface of the nanoparticles to improve the dispersion stability of the nanoparticles in the polymer copolymerization process, thereby inducing uniform dispersion of the nanoparticles in the resin. This is also to maximize the bond strength between the resin and the nanoparticles through chemical bonding with the resin. The amount of the colloidal nanoparticles is preferably used in an amount of 5 to 25% by weight based on the amount of colloidal nanoparticles. When the amount is less than 5% by weight, the lipophilic properties of the nanoparticles are insufficient, so that the dispersion stability is decreased during the copolymerization process. If the compound is not more than 25% by weight, the surface of the nanoparticle and the unreacted alkoxy silane compound are included in the polymer copolymerization reaction, thereby degrading the processability of the copolymer.

Preparation of Nanoparticle Composite Thermoplastic Resin

1 to 15 parts by weight of colloidal nanoparticles having a lipophilic vinyl group introduced to the surface obtained in the above step into a stainless high pressure reactor equipped with a stirrer, 85 to 99 parts by weight of an acrylic monomer, a polymerization initiator, a molecular weight regulator, a suspension stabilizer and an ion exchange 300 parts by weight of water are added and vigorously stirred. The inside of the reactor is filled with an inert gas such as nitrogen or argon and heated to terminate the reaction by polymerizing at 2 to 4 hours at 70 to 80 ° C and 1 to 2 hours at 90 to 110 ° C. After the reaction is completed, the reactor is cooled to room temperature, and the composition prepared is washed, dehydrated and dried to obtain a resin in the form of particles.

The acrylic monomer may be used alone or in a mixture containing methyl methacrylate as a main component and copolymerizable with the acrylic monomer. At this time, methyl methacrylate as a main component should maintain at least 50 parts by weight of the total monomers. When the methyl methacrylate is less than 50 parts by weight, the mechanical strength of the polymerized methacrylic resin is lowered.

There are no particular limitations on the copolymerizable acrylic monomer, and ethyl methacrylate, propyl methacrylate, butyl methacrylate, phenyl methacrylate, benzyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate and butyl acryl It can select from a rate and 2-ethylhexyl acrylate, and can use.

Examples of the polymerization initiator include octane oil peroxide, decanyl oil peroxide, lauroyl peroxide, benzoyl peroxide, monochlorobenzoyl peroxide, dichlorobenzyl peroxide, para methylbenzoyl peroxide, tertiary butyl perbenzoate And azobisisobutyronitrile, azobis- (2,4-dimethyl) -valeronitrile and the like. A polymerization initiator can be used individually or in mixture, and the usage-amount is 0.2-1 weight part is preferable.

Examples of the molecular weight modifier may be selected from alkyl mercaptans such as normal butyl mercaptan, normal octyl mercaptan, normal dodecyl mercaptan, tertiary dodecyl mercaptan, isopropyl mercaptan, and normal amyl mercaptan, and alone or It is preferable to use mixed. The amount of the copolymer is preferably 0.2 to 2 parts by weight, and when the amount is less than this range, the molecular weight of the copolymer produced is greatly increased, resulting in insoluble properties, which causes difficulty in processing, and when used more than this range, the molecular weight of the copolymer is low. Growing on the surface of highly inorganic nanoparticles, the number of molecules copolymerized is small, so that the desired physical and scratch resistance properties cannot be exhibited.

The suspension stabilizer may be classified into an inorganic stabilizer and an organic stabilizer. The inorganic suspension stabilizer may be selected from metal phosphate series such as tricalcium phosphate and trisodium phosphate. However, while the inorganic suspension stabilizer is excellent in polymerization suspension stability, it causes a problem of inhibiting the transparency of the prepared resin remaining in the resin after the reaction. Therefore, the suspension stabilizer used in the present invention is preferably an organic stabilizer, and the organic suspension stabilizer may be a single or copolymer of acrylic acid or methacrylic acid. Especially in the case of copolymers, the content of acrylic acid or methacrylic acid should be at least 50 parts by weight in the stabilizer. They are also preferably in the form of salts of sodium, potassium or ammonium. This is a property required to maintain proper solubility between water as a dispersion medium and monomers suspended. The suspending stabilizer is 0.05 to 0.2 parts by weight is appropriate, the specific content is somewhat different depending on the components and molecular weight of the suspension stabilizer.

The present invention will be further illustrated by the following examples, which are merely illustrative of the present invention and are not intended to limit or limit the scope of the present invention.

Example

Example 1

First step: preparation of colloidal nanoparticles into which an lipophilic vinyl group is introduced

1 part by weight of colloidal silicon dioxide (SiO ₂ , silica) having an average particle diameter of 8 to 10 nm, 5 parts by weight of isopropyl alcohol relative to silica, in a reactor equipped with a stirrer, a heating device, a cooling device, a condenser, and a vacuum device, 5 parts by weight of ion-exchanged water was added to silica, and the mixture was stirred and diluted. To the solution being stirred, 0.2 part by weight of methacryloxyalkyl trimethoxysilane relative to silica was added slowly through a dropwise device. When the addition of the alkoxy compound was completed, the temperature inside the reactor was raised to 60 ° C., and then methyl alcohol, a reaction byproduct, was removed using a vacuum machine for 10 minutes. After removing the vacuum and raising the temperature of the reactor to 80 ℃ and further reaction for 2 hours, the reaction temperature was terminated by cooling the temperature of the reactor to room temperature to prepare colloidal nanoparticles in which a lipophilic vinyl group was introduced on the surface of the nanoparticles. It was.

Second Step: Preparation of Nanoparticle Composite Thermoplastic Resin

The whole colloidal nanoparticle solution in which the lipophilic vinyl group was introduced to the surface prepared in the first step was added to a stainless high pressure reactor equipped with a stirrer, 99 parts by weight of methyl methacrylate, 0.3 part by weight of lauroyl peroxide, and normal 0.25 parts by weight of octyl mercaptan, 0.25 parts by weight of tertiary dodecyl mercaptan, 300 parts by weight of ion-exchanged water, and 0.15 parts by weight of sodium polyacrylate were added, followed by vigorous stirring. The inside of the reactor was filled with nitrogen, heated to reach an internal temperature of 72 ° C. and polymerized for 2 hours, and then the temperature of the reactor was increased to 100 ° C. for polymerization for 2 hours. The reaction was terminated by cooling the temperature of the reactor to room temperature, and the prepared nanoparticle composite thermoplastic resin was washed, dehydrated and dried to obtain powder particles in the form of particles. The thermoplastic acrylic resin of the nanoparticle composite was separately obtained by obtaining a specimen through extrusion and injection processing, and the results are shown in Table 1 below.

Example 2

3 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) and 0.6 parts by weight of methacryloxyalkyl trimethoxysilane were added in the first step, and methyl methacrylate was changed to 97 parts by weight in the second step. The same procedure as in Example 1 was carried out except for the addition.

Example 3

5 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) and 1 part by weight of methacryloxyalkyl trimethoxysilane were added in the first step, and methyl methacrylate was changed to 95 parts by weight in the second step. The same procedure as in Example 1 was carried out except for the addition.

Example 4

10 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) and 2 parts by weight of methacryloxyalkyl trimethoxysilane were added in the first step, and methyl methacrylate was changed to 90 parts by weight in the second step. The same procedure as in Example 1 was carried out except for the addition.

Example 5

In the first step, 5 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) having an average particle diameter of 20 nm and methacryloxyalkyl trimethoxysilane were added to 1.0 part by weight, and in the second step, methyl methacrylate. Was carried out in the same manner as in Example 1 except for changing to 95 parts by weight.

Example 6

In the first step, 10 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) having an average particle diameter of 20 nm and methacryloxyalkyl trimethoxysilane were added to 2.0 parts by weight, and in the second step, methyl methacrylate. Was carried out in the same manner as in Example 1 except for changing to 90 parts by weight.

Comparative Example 1

Example 1 except that 100 parts by weight of methyl methacrylate was added without changing the colloidal nanoparticles in which the lipophilic vinyl group was introduced to the particle surface in the second step by omitting the first step. The same procedure was followed.

Comparative Example 2

In the first step, 5 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) and 1.0 part by weight of methacryloxyalkyl trimethoxysilane were added to prepare colloidal nanoparticles having an organic vinyl group introduced on the surface thereof. After drying, moisture was obtained in powder form, and the powder colloidal nanoparticles thus obtained were blended with 95 parts by weight of methyl methacrylate resin prepared in the same manner as in Comparative Example 1 during extrusion to prepare a specimen.

Comparative Example 3

5 parts by weight of colloidal silicon dioxide (SiO ₂ , silica), which was not subjected to the particle surface treatment in the second step, without the preparation of the first step, was changed to 95 parts by weight of methyl methacrylate. Was carried out in the same manner as in Example 1.

Comparative Example 4

In the first step, 5 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) having an average particle diameter of 100 nm and methacryloxyalkyl trimethoxysilane were added to 1 part by weight, and in the second step, methyl methacrylate. Was carried out in the same manner as in Example 1 except for changing to 95 parts by weight.

Comparative Example 5

5 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) and 2 parts by weight of methacryloxyalkyl trimethoxysilane were added in the first step, and methyl methacrylate was changed to 95 parts by weight in the second step. The same procedure as in Example 1 was carried out except for the addition.

Comparative Example 6

5 parts by weight of colloidal silicon dioxide (SiO ₂ , silica) and 1 part by weight of methacryloxyalkyl trimethoxysilane were added in the first step, and 95 parts by weight of methyl methacrylate in the second step, poly The same procedure as in Example 1 was carried out except that sodium acrylate was changed to 0.5 part by weight of tricalcium phosphate.

As described above, the physical properties of each of the specimens prepared in Examples and Comparative Examples were evaluated by the following method, and the measurement results are shown in Table 1.

(Iii) Light transmittance: It was measured by a color measuring instrument of Suga Instrument, Japan, and the result was expressed by total light transmittance. The total light transmittance (%) is (sample transmitted light / specimen irradiated light) * 100.

(Ii) Flowability: The flowability of the specimen was measured at a load of 10 Kg at 220 ° C. based on ISO 1103. (Unit is g / 10 min)

(iii) Pencil hardness: Based on JIS K5401, a specimen of thickness 3 mm, length 10 cm and width 10 cm was prepared with a load of 500 g at 23 ° C., and applied to the surface of the specimen five times to determine the degree of scratching. When the pencil scratch marks appeared more than once on the specimen surface, the pencil hardness rating was determined as 4B-4H.

(iv) Ball-type Scratch Profile (BSP): A specimen of 3 mm thick, 10 cm long and 10 cm wide was prepared from a spherical metal tip with a load of 1000 g, a speed of 75 mm / min, and a diameter of 0.7 mm at 23 ° C. After the scraping was added to the specimen surface three times, the width of the scratched section (Width) was measured using Ambois Surface Profile Analyzer XP-1. (Unit is μm)

From the results of Table 1, the resin of Examples 1 to 6 prepared according to the production method of the present invention is superior to other physical properties such as transparency and scratch resistance compared to Comparative Examples 1 to 6 outside the scope of the present invention. You can check it.

This invention has the effect of the invention which provides the thermoplastic resin which was excellent in scratch resistance, and was excellent in transparency, and its manufacturing method.

Simple modifications and variations of the present invention can be readily used by those skilled in the art, and all such variations or modifications can be considered to be included within the scope of the present invention.

Claims (10)

The organically dispersed colloidal nanoparticles are mixed with alcohol and ion-exchanged water, and the alkoxy silane compound is added dropwise to the aqueous dispersed colloidal nanoparticles at 5 to 25% by weight to react the lipophilic vinyl on the surface. Preparing colloidal nanoparticles to which groups are introduced; And Suspending and polymerizing colloidal nanoparticles having a lipophilic vinyl group introduced on the surface thereof with an acrylic monomer; A method for producing a thermoplastic resin excellent in scratch resistance, characterized in that it comprises a step. The method for producing a thermoplastic resin having excellent scratch resistance according to claim 1, wherein the colloidal nanoparticles have a diameter of 5 to 50 nm. [Claim 2] The thermoplastic resin having excellent scratch resistance of claim 1, wherein the colloidal nanoparticles having a lipophilic vinyl group introduced therein are used in an amount of 1 to 15 parts by weight based on 100 parts by weight of the mixture of the nanoparticles and the acrylic monomer. Method of preparation. The method of claim 1, wherein the acrylic monomer is methyl methacrylate. The method of claim 1, wherein in the step of the suspension polymerization, a monomer copolymerizable with an acrylic monomer is added, but the content of the acrylic monomer is 50% by weight or more based on the total monomer mixture, the scratch resistance characterized in that the suspension polymerization Excellent method for producing thermoplastic resins. The method of claim 5, wherein the acrylic monomer is methyl methacrylate, the monomer copolymerizable with the acrylic monomer is ethyl methacrylate, propyl methacrylate, butyl methacrylate, phenyl methacrylate, benzyl methacrylate, methyl A method for producing a thermoplastic resin having excellent scratch resistance, characterized in that at least one monomer selected from the group consisting of acrylate, ethyl acrylate, propyl acrylate, butyl acrylate and 2-ethylhexyl acrylate. The method of claim 1, wherein in the suspension polymerization step, octanoyl peroxide, decanyl peroxide, lauroyl peroxide, benzoyl peroxide, monochlorobenzoyl peroxide, dichlorobenzoyl peroxide, para methylbenzoyl peroxide as a polymerization initiator. Scratch resistance characterized by adding at least one polymerization initiator selected from the group consisting of oxide, tertiary butyl perbenzoate, azobisisobutyronitrile and azobis- (2,4-dimethyl) -valeronitrile The manufacturing method of this excellent thermoplastic resin. The method of claim 1, wherein the suspension polymerization step is selected from the group consisting of normal butyl mercaptan, normal octyl mercaptan, normal dodecyl mercaptan, tertiary dodecyl mercaptan, isopropyl mercaptan and normal amyl mercaptan as molecular weight regulators. A method for producing a thermoplastic resin having excellent scratch resistance, characterized in that at least one alkyl mercaptan is used. The suspension stabilizer is a suspension of a metal phosphate series selected from the group consisting of tricalcium phosphate and trisodium phosphate as the suspension stabilizer or the suspension stabilizer is a homopolymer of acrylic acid or methacrylic acid Or these copolymers are used, The manufacturing method of the thermoplastic resin excellent in the scratch-resistant characteristic characterized by the above-mentioned. The thermoplastic resin excellent in the scratch resistance manufactured by the manufacturing method of any one of Claims 1-9.