KR101732230B1 - (Meth)acrylic alkylester containing ABS emulsion graft resin, transparent thermoplastic resin composition and method for preparing thereof - Google Patents

Abstract

The present invention relates to an ABS emulsion grafted resin containing an alkyl (meth) acrylate ester, a transparent thermoplastic resin composition and a process for producing the same. According to the present invention, Thereby providing a transparent thermoplastic resin with high productivity.

Description

[0001] The present invention relates to an ABS emulsion graft resin containing an alkyl ester of [meth] acrylic acid and a transparent thermoplastic resin composition and a method for producing the same,

The present invention relates to an ABS emulsified graft resin containing a (meth) acrylic acid alkyl ester, a transparent thermoplastic resin composition and a process for producing the same. More specifically, the present invention relates to a (meth) acrylic acid alkyl acrylate An ester-containing ABS emulsified graft resin, a transparent thermoplastic resin composition containing the same, and a process for producing the same.

Recently, as the industry has advanced and actively promoted differentiation of products, many changes have occurred in product design, and color diversification and transparent design are also attracting much attention. Material changes are required according to the change of design, and therefore research on the development of transparent materials is actively being carried out.

To this end, techniques for imparting transparency by introducing (meth) acrylic acid alkyl ester monomers into acrylonitrile-butadiene-styrene (ABS) resin excellent in impact resistance, chemical resistance and processability have been developed (Korean Registered No. 0360987, No. 0423873).

For example, the above techniques are produced by preparing ABS powder by graft copolymerizing methyl methacrylate-styrene-acrylonitrile (MSAN) on a conjugated diene rubber and then blending a separately prepared hard MSAN resin.

The ABS powder is usually obtained as a latex which is a mixture of water and resin after polymerization, by salt flocculation, dehydration and drying treatment.

In order to improve the stability of latex during the polymerization, electrolytes such as KHCO3, NaHCO3, Na2CO3, KHSO3, NaHSO3, K4P2O7, K3PO4, Na3PO4, K2HPO4, Na2HPO4 and Na2P2O7 are usually added.

However, when an electrolyte is added during the polymerization and then an alkaline earth metal such as calcium chloride or magnesium sulfate is used as a coagulant in flocculating the salt, the electrolyte remaining in the latex reacts with the alkaline earth metal used as the flocculant to generate the following insoluble salts , Resulting in a problem of remaining in the final product (see Fig. 1).

CaCl 2 + Na 2 CO 3 -> CaCO 3 (insoluble), Na +, Cl-

MgSO4 + Na2P2O7 -> Mg2P2O7 (insoluble), 2Na +, SO4-2

In the case of remaining in the final product, the foreign matter is more visible because it is a transparent product, and even when the composition of the ABS powder and the MSAN resin is extruded by filtering with a filter of about 200 mesh, the cleaning cycle is accelerated due to the foreign matter, There are various problems such as the increase in size as the flocculation process progresses as well as the deposition of the foreign material due to the continuous process during the tank flocculation process, which may result in defective appearance quality in the final product and deterioration of colorability with respect to a specific color ).

For this reason, there is a desperate need for a method capable of overcoming the disadvantages such as poor appearance quality due to the formation of insoluble salts in the transparent resin product to be provided in the present invention, and not deteriorating the latex stability.

In order to solve the problems of the prior art as described above, the present invention relates to an ABS emulsified graft resin containing a (meth) acrylic acid alkyl ester which is stable to latex and prevents the formation of insoluble salts when aggregated, a transparent thermoplastic resin composition containing the And a method for producing the same.

In order to achieve the above object, the present invention provides an ABS emulsified graft resin containing a (meth) acrylic acid alkyl ester containing an alkali metal hydroxide.

The present invention also provides a composition comprising an ABS emulsion grafted resin and an MSAN resin,

Wherein the ABS emulsion graft resin is a powder including the above-mentioned ABS emulsion graft resin containing (meth) acrylic acid alkyl ester and a salt flocculant.

The present invention also relates to a process for preparing a polybutadiene rubber latex by emulsion graft copolymerization at 60 to 75 ° C for 3 to 5 hours while continuously feeding an alkyl (meth) acrylate monomer, an aromatic vinyl monomer, a vinyl cyan monomer, ;

Heating the copolymer to a temperature of 76 to 83 DEG C and aging for 0.5 to 1.5 hours to obtain a latex; And

And subjecting the latex to salt flocculation, dehydration, and drying to obtain a powder. The present invention also provides a method for producing an ABS resin powder.

The present invention also relates to a rubber composition comprising 10 to 60 parts by weight of a polybutadiene rubber latex, 30 to 70 parts by weight of a (meth) acrylic acid alkyl ester monomer, 5 to 25 parts by weight of an aromatic vinyl monomer, and 1 to 5 parts by weight of a vinyl cyan monomer A first step of preparing an emulsified graft copolymer latex by graft copolymerization comprising 0.05 to 0.5 parts by weight of an alkali metal hydroxide, And

And a second step of subjecting the emulsion graft copolymer latex to salt flocculation, dehydration and drying to obtain a powder.

According to the present invention, it is possible to provide a transparent thermoplastic resin which is stable to latex and prevents the formation of insoluble salts upon agglomeration to improve the appearance quality.

FIG. 1 is a photograph showing that an electrolyte remaining in the latex reacts with an alkaline earth metal used as a flocculant to form an insoluble salt when an alkaline earth metal is used when the electrolyte is conventionally polymerized.
FIG. 2 is a photograph showing that the insoluble salt of the final product remained after the insoluble salt of FIG. 1 was used at the time of extrusion.
3 is a photograph showing the absence of formation of an insoluble salt in a product prepared according to Example 1 of the present invention.

Hereinafter, the present invention will be described in detail.

The (meth) acrylic acid alkyl ester-containing ABS emulsified graft resin of the present invention is characterized by containing an alkali metal hydroxide.

The alkali metal hydroxide may be, for example, at least one selected from sodium hydroxide and potassium hydroxide.

The alkali metal hydroxide may be in the range of 0.05 to 0.5 parts by weight based on 100 parts by weight of the total of the latex and the monomers constituting the ABS emulsion graft resin containing the (meth) acrylic acid alkyl ester.

The alkali metal hydroxide is preferably applied to an ABS emulsified graft resin containing an alkyl (meth) acrylate and a composition thereof. In this case, it is preferable to adjust the pH to be lowered by the alkyl (meth) acrylate monomer and ensure the stability of the latex It is effective.

That is, the transparent thermoplastic resin composition of the present invention is a composition comprising an ABS emulsified graft resin and an MSAN resin, wherein the ABS emulsified graft resin comprises the above-mentioned (meth) acrylic acid alkyl ester-containing ABS emulsified graft resin and a salt flocculant And a powder containing the powder.

For example, the (meth) acrylic acid alkyl ester-containing ABS emulsified graft resin may contain 10 to 60 parts by weight of a polybutadiene rubber latex, 30 to 70 parts by weight of a (meth) acrylic acid alkyl ester monomer based on 100 parts by weight of the rubber latex and the total monomers, 5 to 25 parts by weight of an aromatic vinyl monomer, and 1 to 15 parts by weight of a vinyl cyan monomer.

The polybutadiene rubber latex is contained in an amount of, for example, 10 to 60 parts by weight, or 30 to 60 parts by weight, based on 100 parts by weight of the total amount of the rubber latex and the whole monomers. If the impact strength of the molded article is not lowered within the above range And the polymerization stability is also secured.

The (meth) acrylic acid alkyl ester monomer is contained in an amount of, for example, 30 to 70 parts by weight, or 30 to 50 parts by weight based on 100 parts by weight of the total amount of the rubber latex and the total monomers, There is an effect of securing.

Examples of the alkyl (meth) acrylate monomer include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid propyl ester, 2-ethylhexyl (meth) acrylate, (Meth) acrylic acid lauryl ester, and the like.

The aromatic vinyl monomer is contained in an amount of, for example, 5 to 25 parts by weight, or 5 to 15 parts by weight, based on 100 parts by weight of the total amount of the rubber latex and the whole monomers, and the effect of ensuring sufficient workability and transparency within the above range have.

Examples of the aromatic vinyl monomer include styrene,? -Methylstyrene, p-methylstyrene, vinyltoluene, and the like.

The vinyl cyan monomer is contained in an amount of 1 to 15 parts by weight or 1 to 5 parts by weight based on 100 parts by weight of the total amount of the rubber latex and the total monomers, The yellowing phenomenon can be prevented.

As the vinyl cyan monomer, for example, acrylonitrile, methacrylonitrile and the like can be used.

As the method of adding each of the above components, a method of collective administration and a method of administering the whole amount or a part thereof in a continuous (sequential) manner can be used, and it is more preferable to take a complex form in which the batch administration and the continuous administration method are controlled.

The ABS emulsified graft resin may be prepared by emulsion polymerization, for example at 60 to 85 ° C for 3 to 8 hours.

As the emulsion polymerization, for example, 0.2 to 0.6 parts by weight of an emulsifier, 0.2 to 1.5 parts by weight of a molecular weight adjuster, 0.02 to 0.3 part by weight of a polymerization initiator, and 0.1 to 1.0 Parts by weight.

Examples of the emulsifier include alkylaryl sulfonates, alkali metal alkyl sulfates, sulfonated alkyl esters, fatty acid soaps, rosin acid alkali salts, and the like, or a mixture of two or more thereof.

The molecular weight regulator may be mercaptans, for example, tertiary dodecyl mercaptan.

Examples of the polymerization initiator include peroxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, persulfate, sodium formaldehyde sulfoxylate, sodium ethylenediamine tetraacetate, ferrous sulfate, dextrose, sodium pyrophosphate , And a reducing agent such as sodium sulfite may be used.

KHCO3, Na2CO3, KHSO3, NaHSO3, K4P2O7, K3PO4, Na3PO4, K2HPO4, Na2HPO4, and the like can be used alone or as a mixture of two or more thereof.

The salt flocculant may be, for example, selected from calcium chloride, magnesium sulfate, and aluminum sulfate.

The salt flocculant may be contained in an amount of 1 to 3 parts by weight based on 100 parts by weight of the solid latex.

The MSAN resin is, for example, 40 to 75 parts by weight of the (meth) acrylic acid alkyl ester monomer, 15 to 45 parts by weight of the aromatic vinyl monomer, and 3 to 20 parts by weight of the vinyl cyan monomer, based on 100 parts by weight of the total monomers constituting the MSAN resin. And 20 parts by weight of a polyisocyanate compound.

The MSAN resin is, for example, 50 to 70 parts by weight of a (meth) acrylic acid alkyl ester monomer, 15 to 35 parts by weight of an aromatic vinyl monomer, and 7 to 17 parts by weight of a vinyl cyan monomer, based on 100 parts by weight of the total monomers constituting the MSAN resin May be obtained by bulk polymerization.

The (meth) acrylic acid alkyl ester monomer, the aromatic vinyl monomer, and the vinyl cyan monomer may be of the same kind as those used in the emulsion graft copolymerization.

Toluene as a solvent and di-tertiary dodecyl mercaptan as a molecular weight modifier may be contained in the bulk polymerization.

The ABS resin powder and the MSAN resin may contain 20 to 100 wt%, 40 to 80 wt%, or 50 to 70 wt% of the ABS resin powder, 80 to 0 wt%, 60 to 20 wt%, or 50 to 30 wt% of the MSAN resin, . ≪ / RTI >

The composition may further include one or more additives selected from an ultraviolet absorber, an antioxidant, a light stabilizer, a dye, and a pigment, depending on the application and the necessity.

The process for producing the ABS resin powder of the present invention can be carried out, for example, by the following steps:

Performing emulsion graft copolymerization at 60 to 75 ° C for 3 to 5 hours while continuously feeding the polybutadiene rubber latex with a (meth) acrylic acid alkyl ester monomer, an aromatic vinyl monomer, a vinyl cyan monomer, and an alkali salt pH adjusting agent;

Heating the copolymer to a temperature of 76 to 83 DEG C and aging for 0.5 to 1.5 hours to obtain a latex;

And subjecting the latex to salt flocculation, dehydration and drying to obtain a powder.

For reference, the process for producing the ABS resin powder of the present invention does not use an alkali salt pH controlling agent which becomes an insoluble salt during the salt flocculation, and the latex stability is reduced by the use of an alkali metal hydroxide and a (meth) acrylic acid alkyl ester monomer It has a technical characteristic to maintain the stability of latex by controlling pH.

Specifically, the composition of the emulsified graft copolymerization may be to change the type of the alkali salt pH adjusting agent, wherein the alkali salt pH adjusting agent may be an alkali metal hydroxide selected from the above-mentioned sodium hydroxide and potassium hydroxide.

The method of producing the ABS resin powder is very efficient because it increases the pH which is lowered due to the introduction of the alkyl (meth) acrylate monomer to prevent the formation of insoluble salts during the coagulation while securing the stability of the latex.

The process for producing the ABS resin powder of the present invention can be carried out, for example, in the following steps:

10 to 60 parts by weight of a polybutadiene rubber latex, 30 to 70 parts by weight of a (meth) acrylic acid alkyl ester monomer, 5 to 25 parts by weight of an aromatic vinyl monomer,

A first step of preparing an emulsified graft copolymer latex by graft copolymerization comprising 0.05 to 0.5 part by weight of an alkali metal hydroxide based on 100 parts by weight of total of 1 to 5 parts by weight of vinyl cyan monomer; And

A second step of subjecting the emulsion graft copolymer latex to salt flocculation, dehydration and drying to obtain a powder.

Specifically, in the first step, copolymerization is carried out at 65 to 75 ° C for 3.5 to 4.5 hours while continuously introducing an alkyl (meth) acrylate monomer, an aromatic vinyl monomer, a vinyl cyan monomer, and an alkali metal hydroxide into a polybutadiene rubber latex ; And

Heating the copolymer to 76 to 83 ° C, aging for 0.5 to 1.5 hours, and then completing the aging reaction.

The method of producing the ABS resin powder is very efficient because it increases the pH which is lowered due to the introduction of the alkyl (meth) acrylate monomer to prevent the formation of insoluble salts during the coagulation while securing the stability of the latex.

As another example of the method of producing the transparent thermoplastic resin of the present invention, the transparent thermoplastic resin composition comprising the ABS resin powder obtained by the above-mentioned method and the MSAN resin can be extruded.

Specifically, the composition of the emulsified graft copolymerization may be to change the type of alkali salt pH adjusting agent, wherein the alkali salt pH adjusting agent may be an alkali metal hydroxide selected from sodium hydroxide and potassium hydroxide.

Since the production method of the transparent thermoplastic resin can prevent the formation of insoluble salts during the coagulation and improve the quality of the transparent appearance of the final product and improve the productivity by increasing the replacement cycle time of the filter of the 200 mesh extruder in the extrusion step, (See FIG. 3).

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]

Example 1

≪ Preparation of ABS emulsion graft copolymer latex A-1 >

To 50 parts by weight of polybutadiene rubber latex, 100 parts by weight of ion-exchanged water, 1.5 parts by weight of potassium rosinate, 36 parts by weight of methyl methacrylate, 12 parts by weight of styrene, 2 parts by weight of acrylonitrile, 0.5 parts by weight of tertiary dodecylmercaptan , 0.048 part by weight of sodium pyrophosphate, 0.012 part by weight of dextrose, 0.001 part by weight of iron sulfide, 0.04 part by weight of cumene hydroperoxide and 0.05 part by weight of sodium hydroxide were continuously added at 75 DEG C for 4 hours.

Then, the temperature was raised to 80 DEG C, aged for 1 hour, and the reaction was terminated. The polymerization conversion was 98%.

≪ Preparation of ABS resin powder &

The resulting latex was admixed with 3 parts by weight of CaCl2 on the basis of 100 parts by weight of the latex solid component, and the insoluble salt was visually observed during the coagulation while aggregating. The results are summarized in Table 1 below.

Then, the agglomerates were subjected to hot-air drying and dehydration, and the amount of latex coagulated powder in the powder was measured by the following formula, and the results are summarized together in Table 1.

[Formula 1]

Coagulation / theoretical flocculation x 100 (%) = 100mesh to polymerized latex

≪ Preparation of MSAN resin B >

A mixture of 63.36 parts by weight of methyl methacrylate, 24.64 parts by weight of styrene, 12 parts by weight of acrylonitrile, 30 parts by weight of toluene as a solvent, and 0.15 part by weight of di-tertiary dodecyl mercaptan as a molecular weight modifier, And the reaction temperature was maintained at 150 캜.

The polymerized liquid discharged from the reactor was heated in a preheating tank, and the unreacted monomers were volatilized in a volatilization tank and the polymer temperature was maintained at 210 ° C., and the copolymer resin was processed into a pellet using a polymer transfer pump extrusion machine.

<Blend of ABS resin powder and MSAN resin>

The ABS resin powder and the MSAN resin pellets were blended at a weight ratio of 60:40, and the lubricant was added to 1 part by weight on the basis of 100 parts by weight of the blend and extruded in an extruder.

The replacement cycle of the 200 mesh filter in the extruder is also recorded in Table 1 below.

Example 2

The same procedure was repeated except that 0.5 part by weight of sodium hydroxide was added in the step of < Preparation of ABS emulsion graft copolymer latex A-1 in Example 1 to prepare ABS emulsion graft copolymer latex A-2. The polymerization conversion was 97.5%.

Comparative Example 1

The same procedure was repeated except that sodium hydroxide was replaced with sodium hydroxide in the step of < Preparation of ABS emulsion graft copolymer latex A-1 in Example 1 to prepare ABS emulsion graft copolymer latex A-3 . The polymerization conversion rate was 98.0%, and the formation of insoluble salts of CaCO3 was observed visually by the reaction of CaCl2 coagulant and residual Na2CO3 during the coagulation.

Comparative Example 2

The same procedure was repeated except that sodium hydroxide was not added in the step of < Preparation of ABS emulsion graft copolymer latex A-1 in Example 1 to prepare ABS emulsion graft copolymer latex A-4. The polymerization conversion was 97.5%.

Comparative Example 3

The same procedure was repeated except that 0.03 part by weight of sodium hydroxide was added in the step of < Preparation of ABS emulsion graft copolymer latex A-1 in Example 1 to prepare ABS emulsion graft copolymer latex A-5. The polymerization conversion was 97.3%.

Comparative Example 4

The same procedure was repeated except that 0.6 part by weight of sodium hydroxide was added in the step of <Preparation of ABS emulsion graft copolymer latex A-1 in Example 1 to prepare ABS emulsion graft copolymer latex A-6. The polymerization conversion was 97.0%.

The components used in Examples 1-2 and Comparative Examples 1-4 and the observed / measured item values are summarized together in Table 1 below.

division A-1
(wt%) A-2
(wt%) A-3
(wt%) A-4
(wt%) A-5
(wt%) A-6
(wt%) B
(wt%) Lubricant
(Parts by weight) Extruder filter (200 mesh)
Replacement cycle (hr) Room 1 60 40 One 20 Room 2 60 40 One 20 Rain 1 60 40 One 7 Rain 2 60 40 One Not measurable Rain 3 60 40 One Not measurable Rain 4 60 40 One Not measurable Coagulation minutes (%) 0.15 0.20 0.21 1.3 0.39 0.40 Presence or absence of insoluble salts radish radish U radish radish radish

As shown in Table 1, the transparent thermoplastic resin (Examples 1 and 2) comprising the ABS oil-emulsion graft copolymer latex (A-1 or A-2) containing an alkali metal hydroxide according to the present invention was subjected to latex coagulation Minute was 0.2% or less, and the latex stability was excellent. For reference, it is judged that latex stability is excellent when the solid content of the new product is within 0.3%.

In addition, since the latex stability is excellent and the insoluble salt is not produced, not only the productivity is improved when the replacement cycle of the 200 mesh filter of the extruder is taken into account, and the 200 mesh filter is replaced with the 100 mesh filter.

On the other hand, a transparent thermoplastic resin containing an ABS emulsion graft copolymer latex (A-4, A-5, or A-6) containing an alkali metal hydroxide or containing a small amount or an excess of the alkali metal hydroxide, And it can be confirmed that the latex stability is broken due to instability in the latex polymerization.

The transparent thermoplastic resin containing the ABS emulsion graft copolymer latex (A-3) using a conventional electrolyte in place of the alkali metal hydroxide was excellent in latex stability. However, due to salt aggregation after the flocculation process, And when the extruder is extruded using the extruder, the productivity of the extruder is reduced in terms of the production cost because the replacement cycle of the extruder filter is fast and the production efficiency is low.

Claims (10)

In an ABS emulsified graft resin containing an alkyl (meth) acrylic acid alkyl ester, which contains an alkali metal hydroxide,
Wherein the alkali metal hydroxide is in the range of 0.05 to 0.5 parts by weight based on 100 parts by weight of the total of the latex and the monomers constituting the ABS emulsion graft resin containing the alkyl (meth) acrylate. Emulsion grafted resin. The method according to claim 1,
Wherein the alkali metal hydroxide is selected from sodium hydroxide and potassium hydroxide. &Lt; RTI ID = 0.0 &gt; (meth) &lt; / RTI &gt; delete A composition comprising an ABS emulsion grafted resin and an MSAN resin, wherein the ABS emulsion grafted resin comprises a (meth) acrylic acid alkyl ester-containing ABS emulsion graft resin according to any one of claims 1 to 2 and a salt flocculant Wherein the transparent thermoplastic resin composition is a powder of a thermoplastic resin. 5. The method of claim 4,
The ABS (meth) acrylic acid alkyl ester-containing ABS emulsion graft resin is prepared by mixing 10 to 60 parts by weight of a polybutadiene rubber latex, 30 to 70 parts by weight of a (meth) acrylic acid alkyl ester monomer based on 100 parts by weight of a rubber latex and all monomers, 5 to 25 parts by weight of an aromatic vinyl monomer and 1 to 15 parts by weight of a vinyl cyan monomer. 5. The method of claim 4,
Wherein the salt flocculant is selected from calcium chloride, magnesium sulfate, and aluminum sulfate. delete delete 10 to 60 parts by weight of a polybutadiene rubber latex, 30 to 70 parts by weight of a (meth) acrylic acid alkyl ester monomer, 5 to 25 parts by weight of an aromatic vinyl monomer,
A first step of preparing an emulsified graft copolymer latex by graft copolymerization comprising 0.05 to 0.5 part by weight of an alkali metal hydroxide based on 100 parts by weight of total of 1 to 5 parts by weight of vinyl cyan monomer; And
And a second step of subjecting the emulsion graft copolymer latex to salt flocculation, dehydration and drying to obtain a powder. 10. The method of claim 9,
The first step is a step of performing copolymerization for 3.5 to 4.5 hours at 65 to 75 ° C while continuously feeding the (meth) acrylic acid alkyl ester monomer, the aromatic vinyl monomer, the vinyl cyan monomer, and the alkali metal hydroxide to the polybutadiene rubber latex; And
Heating the copolymer to 76 to 83 ° C, aging the mixture for 0.5 to 1.5 hours, and then completing the aging reaction.

Images