KR20230052216A - Method of preparing polymer - Google Patents

Abstract

The present invention is to produce a polymer that is excellent in alcohol resistance, impact resistance, and transparency. The present invention comprises the steps of: continuously adding, to a first reactor, a monomer mixture containing a (meth)acrylate monomer, a vinyl aromatic monomer, and a first vinyl cyanide monomer for polymerization of the same to prepare a first polymer mixture; polymerizing a second vinyl cyanide monomer and the first polymer mixture by continuously adding the same to a second reactor to prepare a second polymer mixture. The starting point of continuous addition of the second vinyl cyanide monomer and the first polymer mixture is when the polymerization conversion rate is 40.0 to 55.0 %, and the weight ratio of the first vinyl cyanide monomer and the second vinyl cyanide monomer is 10 : 90 to 35 : 65.

Description

Manufacturing method of polymer {METHOD OF PREPARING POLYMER}

[Mutual Citation with Related Applications]

The present invention claims the benefit of priority based on Korean Patent Application No. 10-2021-0135257 filed on October 12, 2021, and includes all contents disclosed in the literature of the Korean patent application as part of this specification.

[Technical field]

The present invention relates to a method for producing a polymer, and specifically, to a method for producing a polymer having excellent alcohol resistance, impact resistance and transparency.

Acrylic polymers prepared by polymerization of (meth)acrylate-based monomers, vinyl aromatic monomers, and vinyl cyanide-based monomers have excellent transparency, moldability, rigidity, and electrical properties, and thus are used in office equipment, home appliances, It is widely used in various industrial fields such as automobile parts and miscellaneous goods.

Since these acrylic polymers contain a high content of (meth)acrylate-based monomer units in order to realize excellent transparency, alcohol resistance is very poor. However, since the use of alcohol disinfectants has recently increased due to COVID-19, the use of acrylic polymers is inevitably limited if alcohol resistance, impact resistance and transparency are not all excellent.

Accordingly, there is a need to develop an acrylic polymer having excellent alcohol resistance, impact resistance, and transparency.

JP3390529B

The problem to be solved by the present invention is to prepare a polymer having excellent alcohol resistance, impact resistance and transparency.

(1) The present invention comprises the steps of preparing a first polymer mixture by polymerizing while continuously introducing a monomer mixture including a (meth)acrylate-based monomer, a vinyl aromatic monomer, and a first vinyl cyanide-based monomer into a first reactor; and preparing a second polymer mixture by polymerizing while continuously introducing a second vinyl cyanide-based monomer and the first polymer mixture into a second reactor, wherein the second vinyl cyanide-based monomer and the first polymer mixture The starting point of continuous addition is when the polymerization conversion rate is 40.0 to 55.0%, and the weight ratio of the first vinyl cyanide-based monomer to the second vinyl cyanide-based monomer is 10:90 to 35:65. .

(2) The present invention provides a method for preparing a polymer according to (1) above, wherein the starting point of continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture is the point at which the polymerization conversion rate is 40.0 to 50.0%.

(3) In the present invention, in (1) or (2), the weight ratio of the first vinyl cyanide-based monomer and the second vinyl cyanide-based monomer is 20:80 to 30:70. provides

(4) In the present invention, in any one of (1) to (3), the total sum of the contents of the first vinyl cyanide-based monomer and the second vinyl cyanide-based monomer is the monomer introduced in the method for preparing the polymer Based on 100 parts by weight of the total sum of the contents, it provides a method for producing a polymer of 20 to 30 parts by weight.

(5) In the present invention, in any one of (1) to (4), the content of the (meth)acrylate-based monomer is based on 100 parts by weight of the total amount of monomers added in the method for preparing the polymer, It provides a method for producing a polymer that is 50 to 65 parts by weight.

(6) In the present invention, in any one of (1) to (5), the content of the vinyl aromatic monomer is 15 to 25 parts by weight, based on 100 parts by weight of the total amount of monomers added in the method for preparing the polymer. It provides a method for producing a polymer that is a part by weight.

(7) The present invention provides a method for producing a polymer according to any one of (1) to (6) above, wherein the internal temperature of the second reactor is higher than the internal temperature of the first reactor.

(8) The present invention provides a method for producing a polymer according to (7) above, wherein the internal temperature of the first reactor and the second reactor is 130 to 150 ° C, respectively.

(9) The present invention provides a method for producing a polymer according to any one of (1) to (7) above, wherein the polymerization is continuous polymerization.

According to the method for preparing the polymer of the present invention, a polymer having excellent alcohol resistance, impact resistance and transparency can be prepared.

Hereinafter, the present invention will be described in more detail to aid understanding of the present invention.

Terms or words used in this specification and claims should not be construed as being limited to ordinary or dictionary meanings, and the inventor may appropriately define the concept of terms in order to explain his or her invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that there is.

The term '(meth)acrylate-based monomer' used in the present invention may mean an alkyl (meth)acrylate-based monomer. The (meth)acrylate-based monomer may be a term encompassing both acrylate-based monomers and methacrylate-based monomers. The alkyl (meth) acrylate monomer is selected from the group consisting of a methyl (meth) acrylate monomer, an ethyl (meth) acrylate monomer, a propyl (meth) acrylate monomer, and a butyl (meth) acrylate monomer It may be at least one, and among them, methyl methacrylate, which is excellent in improving transparency and scratch resistance, is preferable.

In addition, the unit derived from the '(meth)acrylate-based monomer' may be a '(meth)acrylate-based monomer unit'.

The term 'vinyl aromatic monomer' used in the present invention includes styrene, 4-fluorostyrene, 4-chlorostyrene, 2-chlorostyrene, 4-bromostyrene and 2-bromostyrene, α-methyl styrene, p- It may be at least one selected from the group consisting of methyl styrene and 2,4-dimethyl styrene, of which styrene having excellent processability is preferable.

And, the unit derived from the 'vinyl aromatic monomer' may be a 'vinyl aromatic monomer unit'.

The term 'vinyl cyanide-based monomer' used in the present invention means at least one selected from the group consisting of acrylonitrile, 2-methylacrylonitrile, 2-ethylacrylonitrile and 2-chloroacrylonitrile. can Among them, acrylonitrile, which is excellent in the effect of improving chemical resistance, is preferable.

Also, a unit derived from the 'vinyl cyanide-based monomer' may be a 'vinyl cyanide-based monomer unit'.

The term 'monomer mixture' used in the present invention may mean a mixture that does not contain any polymers.

The term 'polymer mixture' used in the present invention may mean a mixture containing even a small amount of a polymer.

The term 'polymerization conversion rate' used in the present invention can be calculated by the following formula:

Polymerization conversion rate (%) = {(total weight of monomers added until polymerization was completed)-(total weight of unreacted monomers at the time of measuring polymerization conversion)}/ (total weight of monomers added until polymerization was completed) weight) × 100

The term 'polymerization' used in the present invention may be 'continuous polymerization' that is easy to remove heat during polymerization and can produce a polymer having uniform physical properties.

The term 'polymerization' used in the present invention may be 'bulk polymerization', and unlike general bulk polymerization that does not use a solvent at all, a small amount of solvent may be used. When a solvent is used, it can be called 'solution polymerization'.

Polymer manufacturing method

A method for producing a polymer according to an embodiment of the present invention is 1) polymerization while continuously introducing a monomer mixture including a (meth)acrylate-based monomer, a vinyl aromatic monomer, and a first vinyl cyanide-based monomer into a first reactor preparing a first polymer mixture; and 2) preparing a second polymer mixture by polymerizing while continuously introducing a second vinyl cyanide-based monomer and the first polymer mixture into a second reactor, wherein the second vinyl cyanide-based monomer and the first polymer The starting point of continuous addition of the mixture is when the polymerization conversion rate is 40.0 to 55.0%, and the weight ratio of the first vinyl cyanide-based monomer and the second vinyl cyanide-based monomer is 10:90 to 35:65. to provide.

Hereinafter, a method for preparing a polymer according to an embodiment of the present invention will be described in detail.

1) Preparation of the first polymer mixture

First, while continuously introducing a monomer mixture including a (meth)acrylate-based monomer, a vinyl aromatic monomer, and a first vinyl cyanide-based monomer into a first reactor, a first polymer mixture is prepared.

The content of the (meth)acrylate-based monomer in the monomer mixture is 62.0 to 62.0 to 100 parts by weight of the total sum of the contents of the (meth)acrylate-based monomer, the vinyl aromatic monomer, and the first vinyl cyanide-based monomer in the monomer mixture. 80.0 parts by weight, preferably 67.0 to 75.0 parts by weight. If the above conditions are satisfied, a polymer having excellent transparency can be produced.

The content of the vinyl aromatic monomer in the monomer mixture is 15.0 to 30.0 parts by weight based on 100 parts by weight of the total sum of the contents of the (meth)acrylate monomer, the vinyl aromatic monomer, and the first vinyl cyanide monomer in the monomer mixture. , preferably 18.0 to 26.0 parts by weight. If the above conditions are satisfied, a polymer having excellent processability and impact resistance can be prepared.

The content of the vinyl cyanide-based monomer in the monomer mixture is 1.0 to 15.0 parts by weight based on 100 parts by weight of the total sum of the contents of the (meth)acrylate-based monomer, the vinyl aromatic monomer, and the first vinyl cyanide-based monomer in the monomer mixture. part, preferably 4.0 to 10.0 parts by weight. When the above conditions are satisfied, a polymer with improved chemical resistance can be prepared while minimizing yellow expression. In addition, it is possible to prepare a polymer having excellent color and transparency by preventing an excessive increase in polymerization conversion at the beginning of polymerization.

The (meth)acrylate-based monomer and the vinyl aromatic-based monomer are preferably introduced only into the first reactor in order to increase the content of the vinyl cyanide-based monomer unit of the final polymer.

Meanwhile, the monomer mixture may further include an initiator and a solvent.

The initiator is 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)-2-methylcyclohexane, 1,1-bis(t-butylperoxy)- It may be at least one selected from the group consisting of 3,3,5-trimethylcyclohexane and 2,2-bis(t-butylperoxy)butane.

The amount of the initiator may be 0.01 to 1.00 parts by weight, preferably 0.01 to 0.50 parts by weight, based on 100 parts by weight of the total amount of monomers added in the method for preparing the polymer. When the above range is satisfied, polymerization can be stably performed.

The solvent may be at least one selected from the group consisting of methyl ethyl ketone, ethylbenzene, toluene, carbon tetrachloride, and chloroform.

The content of the solvent is preferably 20.0 parts by weight or less based on 100 parts by weight of the total amount of monomers added in the method for preparing the polymer, in order to prevent smooth polymerization due to a decrease in the viscosity of the monomer mixture. do.

The internal temperature of the first reactor may be 130 to 150 °C, preferably 130 to 145 °C. When the above conditions are satisfied, phase conversion from a monomer to a polymer may be facilitated.

2) Preparation of the second polymer mixture

Subsequently, a second polymer mixture is prepared by polymerization while continuously introducing a second vinyl cyanide-based monomer and the first polymer mixture into a second reactor.

At this time, the starting point of the continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture may be a time when the polymerization conversion rate is 40.0 to 55.0%, preferably 40.0 to 50.0%. If the continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture is started earlier than the above-mentioned time point, even if the content of the vinyl cyanide-based monomer unit in the polymer is the same, not only the alcohol resistance is significantly lowered, but also Due to the vinyl cyanide-based monomer unit in the polymer, yellow color is expressed, and both color characteristics and transparency are deteriorated. In addition, since a polymer having a uniform composition throughout the polymerization is not prepared, the impact resistance is lowered. If the continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture starts at a later time than the above-mentioned time, the content of the vinyl cyanide-based monomer unit of the polymer as a final product does not increase and the alcohol resistance is lowered.

Meanwhile, the weight ratio of the first vinyl cyanide-based monomer to the second vinyl cyanide-based monomer may be 10:90 to 35:65, preferably 20:80 to 30:70. If the above conditions are satisfied, a polymer including vinyl cyanide-based monomer units uniformly throughout the polymerization can be prepared, and thus the polymer can have excellent transparency, color characteristics, impact resistance, and alcohol resistance. When the first vinyl cyanide-based monomer is included in a smaller amount than the above-mentioned conditions, the transparency, impact resistance and alcohol resistance of the polymer deteriorate. When the first vinyl cyanide-based monomer is included in an excess amount than the above-mentioned conditions, the impact resistance and alcohol resistance of the polymer are lowered.

The total sum of the contents of the first vinyl cyanide-based monomer and the second vinyl cyanide-based monomer is 20.0 to 35.0 parts by weight, preferably 20.0 to 30.0 parts by weight. When the above-mentioned range is satisfied, a polymer having excellent alcohol resistance, improved rigidity and excellent impact resistance can be manufactured.

The content of the (meth)acrylate-based monomer may be 50.0 to 65.0 parts by weight, preferably 50.0 to 60.0 parts by weight, based on 100 parts by weight of the total amount of monomers added in the method for preparing the polymer. When the above range is satisfied, a polymer having excellent transparency and color characteristics can be prepared.

The content of the vinyl aromatic monomer may be 15.0 to 25.0 parts by weight, preferably 15.0 to 20.0 parts by weight, based on 100 parts by weight of the total amount of monomers added in the method for preparing the polymer. When the above range is satisfied, a polymer having excellent processability can be produced.

The internal temperature of the second reactor may be higher than the internal temperature of the first reactor, preferably 5 to 15 ° C, more preferably 7 to 13 ° C, in order to increase the final polymerization conversion rate. And, the internal temperature of the second reactor may be 130 to 150 ℃, preferably 140 to 150 ℃. If the above conditions are satisfied, the final polymerization conversion rate can be increased, and the production efficiency can be improved.

In the method for producing a polymer according to an embodiment of the present invention, the second polymer mixture may be additionally polymerized in a third reactor in order to increase the final polymerization conversion rate. In addition, the third polymer mixture discharged from the third reactor may be further polymerized in the fourth reactor.

Meanwhile, when the polymerization is completed, the finally obtained polymer mixture may be transferred to a devolatilization tank in order to remove unreacted monomers and solvents included in the finally obtained polymer mixture. The temperature of the devolatilization tank may be 225 to 250 °C and the pressure may be 18 torr or less. If the above conditions are satisfied, unreacted monomers and solvents can be easily volatilized to produce a high-purity copolymer.

Hereinafter, preferred embodiments are presented to aid understanding of the present invention, but the following examples are merely illustrative of the present invention, and various changes and modifications are possible within the scope and spirit of the present invention. It is obvious to those skilled in the art, It goes without saying that these variations and modifications fall within the scope of the appended claims.

Example 1

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 130° C.) at a rate of 9.0 kg/hr, and the mixture was continuously polymerized while remaining in the first reactor for 2.6 hours to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 1.2 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing the second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 43.1%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Example 2

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 135° C.) at a rate of 9.0 kg/hr, and kept in the first reactor for 2.6 hours for continuous polymerization to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 1.2 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing the second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of the acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 47.3%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Example 3

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 140° C.) at a rate of 9.0 kg/hr, and the mixture was continuously polymerized while remaining in the first reactor for 2.6 hours to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 150 ° C.) at a rate of 1.2 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing the second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of the acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 51.6%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Example 4

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 145° C.) at a rate of 9.0 kg/hr, and continuously polymerized while remaining in the first reactor for 2.6 hours to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 1.2 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing the second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture to the second reactor was started was the point at which the polymerization conversion rate was 54.9%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Example 5

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 135° C.) at a rate of 9.0 kg/hr, and kept in the first reactor for 2.6 hours for continuous polymerization to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 3.0 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing the second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 47.6%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Example 6

<Preparation of Polymer>

57.0 parts by weight of methyl methacrylate (MMA), 17.4 parts by weight of styrene (ST), 5.6 parts by weight of acrylonitrile (AN), 20.0 parts by weight of toluene (TLN) and 1,1-bis(t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 135° C.) at a rate of 9.0 kg/hr, and kept in the first reactor for 2.6 hours for continuous polymerization to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 2.0 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.6 hours While continuously polymerizing the second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of the acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 47.8%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene and acrylonitrile with butadiene rubber polymer, refractive index: 1.517) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Example 7

<Preparation of Polymer>

Methyl methacrylate (MMA) 57.0 parts by weight, styrene (ST) 17.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20 parts by weight and 1,1-bis (t-butylperoxy) cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 135° C.) at a rate of 145 kg/hr, and the mixture was continuously polymerized while remaining in the first reactor for 2.6 hours to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 2.5 kg / hr and the first polymer mixture at a rate of 9 kg / hr, respectively, and stayed in the second reactor for 2.5 hours While continuously polymerizing the second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 47.5%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Comparative Example 1

<Preparation of Polymer>

49.4 parts by weight of methyl methacrylate (MMA), 16.2 parts by weight of styrene (ST), 16.7 parts by weight of acrylonitrile (AN), 17.6 parts by weight of toluene (TLN) and 1,1-bis(t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 135° C.) at a rate of 11.0 kg/hr, and the mixture was continuously polymerized while remaining in the first reactor for 2.1 hours to prepare a first polymer mixture.

The first polymer mixture was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 11.0 kg / hr, and the second polymer mixture was continuously polymerized while remaining in the second reactor for 2.6 hours to prepare a second polymer mixture. . On the other hand, the point at which the continuous introduction of the first polymer mixture to the second reactor was started was the point at which the polymerization conversion rate was 61.2%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Comparative Example 2

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 135° C.) at a rate of 9.0 kg/hr, and kept in the first reactor for 2.6 hours for continuous polymerization to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 0.8 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing, a second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture to the second reactor was started was the point at which the polymerization conversion rate was 47.9%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Comparative Example 3

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 120° C.) at a rate of 9.0 kg/hr, and continuously polymerized while remaining in the first reactor for 2.6 hours to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 1.2 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing, a second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 35.7%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Comparative Example 4

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 160° C.) at a rate of 9.0 kg/hr, and the mixture was continuously polymerized while remaining in the first reactor for 2.6 hours to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 1.2 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing, a second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 59.9%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Comparative Example 5

<Preparation of Polymer>

Methyl methacrylate (MMA) 56.0 parts by weight, styrene (ST) 18.4 parts by weight, acrylonitrile (AN) 5.6 parts by weight, toluene (TLN) 20.0 parts by weight and 1,1-bis (t-butylperoxy)cyclo A monomer mixture was prepared by mixing 0.03 parts by weight of hexane.

The monomer mixture was continuously introduced into the first reactor (internal temperature: 160° C.) at a rate of 9.0 kg/hr, and the mixture was continuously polymerized while remaining in the first reactor for 2.6 hours to prepare a first polymer mixture.

Acrylonitrile was continuously introduced into the second reactor (internal temperature: 145 ° C.) at a rate of 5.0 kg / hr and the first polymer mixture at a rate of 9.0 kg / hr, respectively, and stayed in the second reactor for 2.8 hours While continuously polymerizing, a second polymer mixture was prepared. On the other hand, the point at which the continuous introduction of acrylonitrile and the first polymer mixture into the second reactor was started when the polymerization conversion rate was 47.6%.

While the second polymer mixture was continuously introduced into a devolatilization tank (internal temperature: 235° C., internal pressure: 15 torr), unreacted monomers and toluene were recovered and removed, and a polymer in a pellet form was prepared.

Meanwhile, the continuous polymerization in the first and second reactors was performed after reaching a steady state.

<Preparation of thermoplastic resin composition>

70 parts by weight of the polymer, 30 parts by weight of a diene-based graft polymer (TR550 from LG Chem, a graft polymer obtained by polymerizing methyl methacrylate, styrene, and acrylonitrile with butadiene rubber polymer, refractive index: 1.516) 30 parts by weight, antioxidant ( A thermoplastic resin composition containing 0.2 parts by weight of BASF's Irganox 1010) was prepared.

Experimental Example 1

The composition and polymerization conversion rate of the polymers of Examples and Comparative Examples were measured or calculated by the method described below, and the results are shown in Tables 1 to 3 below.

1) Composition of the polymer (% by weight): The composition of the polymer was analyzed by obtaining the contents of nitrogen and oxygen with an elemental analyzer (EA3000 from Eurovector).

Experimental Example 2

The physical properties of the polymers of Examples and Comparative Examples were measured by the methods described below, and the results are shown in Tables 1 to 3 below.

1) b value: The b value was measured using a hunter lab colorimeter.

Experimental Example 3

Specimens were prepared by extruding and injecting the thermoplastic resin compositions of Examples and Comparative Examples. The physical properties of the specimen were measured by the method described below, and the results are shown in Tables 1 to 3 below.

1) Haze (%): The haze of the specimen (thickness: 3.175 mm) was measured according to ASTM D1003.

2) Izod impact strength (kg cm/cm, 1/4 In): measured at 25°C according to ASTM D265.

3) Alcohol resistance: After fixing the specimen in a jig with 1.0% stress, isopropyl alcohol (concentration: 100% by weight) was applied to the center of the specimen, left for 5 hours, and then cracks and fractures were checked.

○: No cracks or fractures

△: Crack generation, no breakage

×: occurrence of cracks and fractures

division Example 1 Example 2 Example 3 Example 4 Example 5 monomer mixture
(parts by weight) MMA 56.0 56.0 56.0 56.0 56.0 ST 18.4 18.4 18.4 18.4 18.4 AN 5.6 5.6 5.6 5.6 5.6 TLN 20.0 20.0 20.0 20.0 20.0 initiator 0.03 0.03 0.03 0.03 0.03 Reactor 1 Internal temperature (℃) 130 140 135 145 135 monomer mixture
(kg/hr) 9.0 9.0 9.0 9.0 9.0 second reactor Internal temperature (℃) 145 145 150 145 145 Input point
(polymerization conversion rate, %) 43.1 47.3 51.6 54.9 47.6 AN (kg/hr) 1.2 1.2 1.2 1.2 3.0 First polymer mixture (kg/hr) 9.0 9.0 9.0 9.0 9.0 Input monomer composition
(weight%) MMA about 59.3 about 60.0 about 60.0 about 60.7 about 50.1 ST about 20.5 about 19.7 about 19.7 about 18.8 about 15.8 AN about 20.2 about 20.3 about 20.3 about 20.5 about 34.1 Weight ratio of AN introduced into the first and second reactors about 30:70 about 30:70 about 30:70 about 30:70 about 14:86 polymer composition
(weight%) MMA MU 59.1 59.9 60.1 60.9 49.9 STMU 20.3 19.5 19.3 18.6 16.1 AN MU 20.6 20.5 20.7 20.5 34.0 polymer properties refractive index 1.5162 1.5157 1.5154 1.5151 1.5159 Specimen properties haze 1.5 1.6 1.5 1.4 1.7 impact strength 13.9 13.4 13.7 14.1 17.1 alcohol resistance ○ ○ ○ ○ ○ MMA: methyl methacrylate
MMA MU: methyl methacrylate monomer unit
ST: styrene
ST MU: styrene monomer unit
AN: acrylonitrile
AN MU: acrylonitrile monomer unit
TLN: toluene
Initiator: 1,1-bis(t-butylperoxy)cyclohexane

division Example 6 Example 7 monomer mixture
(parts by weight) MMA 57.0 57.0 ST 17.4 17.4 AN 5.6 5.6 TLN 20.0 20.0 initiator 0.03 0.03 Reactor 1 Internal temperature (℃) 135 135 monomer mixture
(kg/hr) 9.0 9.0 second reactor Internal temperature (℃) 145 145 Input point
(polymerization conversion rate, %) 47.8 47.5 AN (kg/hr) 2.0 2.5 First polymer mixture (kg/hr) 9.0 9.0 Input monomer composition
(weight%) MMA about 55.8 about 52.9 ST about 17.0 about 16.1 AN about 27.2 about 31.0 Weight ratio of AN introduced into the first and second reactors about 20:80 about 17:83 polymer composition
(weight%) MMA MU 53.3 51.9 STMU 17.1 15.4 AN MU 29.6 32.7 polymer properties refractive index 1.5160 1.5152 Specimen properties haze 1.7 1.4 impact strength 15.7 16.4 alcohol resistance ○ ○ MMA: methyl methacrylate
MMA MU: methyl methacrylate monomer unit
ST: styrene
ST MU: styrene monomer unit
AN: acrylonitrile
AN MU: acrylonitrile monomer unit
TLN: toluene
Initiator: 1,1-bis(t-butylperoxy)cyclohexane

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 monomer mixture
(parts by weight) MMA 49.4 56.0 56.0 56.0 56.0 ST 16.2 18.4 18.4 18.4 18.4 AN 16.7 5.6 5.6 5.6 5.6 TLN 17.6 20.0 20.0 20.0 20.0 initiator 0.03 0.03 0.03 0.03 0.03 Reactor 1 Internal temperature (℃) 135 135 120 160 135 monomer mixture
(kg/hr) 11.0 9.0 9.0 9.0 9.0 second reactor Internal temperature (℃) 145 145 145 145 145 point of input
(polymerization conversion rate, %) 61.2 47.9 35.7 59.9 47.6 AN (kg/hr) 0 0.8 1.2 1.2 5.0 First polymer mixture (kg/hr) 11.0 9.0 9.0 9.0 9.0 Input monomer composition
(weight%) MMA about 60.0 about 63.0 about 59.3 about 61.0 about 43.8 ST about 19.7 about 20.7 about 20.8 about 18.9 about 14.8 AN about 20.3 about 16.3 about 19.9 about 20.1 about 41.4 Weight ratio of AN introduced into the first and second reactors - about 39:61 about 30:70 about 30:70 about 9:91 polymer composition
(weight%) MMA MU 60.3 62.8 59.1 60.4 43.6 STMU 19.6 20.9 20.5 19.2 14.9 AN MU 20.1 16.3 20.4 20.4 41.5 polymer properties refractive index 1.5156 1.5158 1.5165 1.5150 1.5174 Specimen properties haze 2.8 1.6 1.9 2.5 3.2 impact strength 11.1 9.8 11.2 9.5 7.3 alcohol resistance △ △ ○ △ △ MMA: methyl methacrylate
MMA MU: methyl methacrylate monomer unit
ST: styrene
ST MU: styrene monomer unit
AN: acrylonitrile
AN MU: acrylonitrile monomer unit
TLN: toluene
Initiator: 1,1-bis(t-butylperoxy)cyclohexane

Referring to Tables 1 to 3, in Examples 1 to 7, the refractive index did not decrease even when the content of the acrylonitrile monomer unit contained in the polymer was high, so the haze value of the specimen was low, the impact strength was high, and the alcohol resistance was high. found to be excellent. However, in Comparative Example 1, in which acrylonitrile was not dividedly added, even if acrylonitrile of the same level as Examples 1 to 7 was added, the impact strength and alcohol resistance of the specimen were lowered, and the haze value was increased. .

The weight ratio of acrylonitrile introduced into the first and second reactors is about 39:61, and Comparative Example 2, in which a small amount of acrylonitrile is added compared to Examples 1 to 7, has impact strength and Alcohol resistance was markedly lowered.

On the other hand, comparing Examples 1 to 5, Comparative Example 3 and Comparative Example 4, Comparative Example 3 having a polymerization conversion rate of 35.7% at the start of continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture , Compared to Examples 1 to 5, the haze value of the specimen increased and the impact strength decreased.

In Comparative Example 4, in which the polymerization conversion rate was 59.9% at the start of the continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture, the refractive index of the polymer and the haze value of the specimen were higher than those of Examples 1 to 5. In addition, the impact strength and alcohol resistance of the specimen were remarkably reduced.

Claims (9)

preparing a first polymer mixture by polymerizing a monomer mixture including a (meth)acrylate-based monomer, a vinyl aromatic monomer, and a first vinyl cyanide-based monomer in a first reactor; and
preparing a second polymer mixture by polymerizing while continuously introducing a second vinyl cyanide-based monomer and the first polymer mixture into a second reactor;
The starting time of the continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture is the time when the polymerization conversion rate is 40.0 to 55.0%,
The weight ratio of the first vinyl cyanide-based monomer and the second vinyl cyanide-based monomer is 10:90 to 35:65.
The method of claim 1,
The starting point of the continuous introduction of the second vinyl cyanide-based monomer and the first polymer mixture is the point at which the polymerization conversion rate is 40.0 to 50.0%.
The method of claim 1,
The weight ratio of the first vinyl cyanide-based monomer and the second vinyl cyanide-based monomer is 20:80 to 30:70.
The method of claim 1,
The total sum of the content of the first vinyl cyanide-based monomer and the second vinyl cyanide-based monomer is 20.0 to 30.0 parts by weight based on 100 parts by weight of the total amount of monomers added in the method for producing the polymer.
The method of claim 1,
The content of the (meth) acrylate-based monomer is 50.0 to 65.0 parts by weight based on 100 parts by weight of the total amount of monomers introduced in the method for producing the polymer.
The method of claim 1,
The content of the vinyl aromatic monomer is 15.0 to 25.0 parts by weight based on 100 parts by weight of the total amount of monomers introduced in the method for producing the polymer.
The method of claim 1,
The internal temperature of the second reactor is a method for producing a polymer that is higher than the internal temperature of the first reactor.
The method of claim 7,
The internal temperature of the first reactor and the second reactor is 130 to 150 ℃, respectively, a method for producing a polymer.
The method of claim 1,
The polymerization is a method for producing a polymer that is a continuous polymerization.