JP2002348449A - Thermoplastic resin composition with excellent processability - Google Patents

Abstract

(57) [Problem] To provide an amorphous polyethylene terephthalate resin composition excellent in processability. SOLUTION: (A) 100 parts by weight of an amorphous polyethylene terephthalate resin and (B) methyl methacrylate 50 to 50 parts by weight.
A mixture (b-1) of 80% by weight, 50 to 20% by weight of an alkyl methacrylate having an alkyl group having 2 to 8 carbon atoms, and 0 to 20% by weight of a vinyl monomer copolymerizable therewith.
60 to 95 parts by weight are polymerized, and in the presence of the resulting polymer latex, 20 to 80% by weight of one or more monomers selected from alkyl methacrylate and alkyl acrylate excluding methyl methacrylate and methyl methacrylate 80-2
A two-stage polymer obtained by polymerizing 40 to 5 parts by weight of a mixture (b-2) with 0% by weight.
A thermoplastic resin composition comprising 0.1 to 10 parts by weight of a polymer having a specific viscosity of 2 to 5 at 30 ° C. in a solution dissolved in 00 ml of toluene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an amorphous polyethylene terephthalate resin composition having excellent moldability.

[0002]

2. Description of the Related Art Amorphous polyethylene terephthalate resin has excellent transparency, mechanical properties and gas barrier properties, and is widely used in packaging materials such as bottles. In particular, recently, its use in sheets and films has been increasing due to its excellent transparency. However, amorphous polyethylene terephthalate resin has a large viscosity change depending on the melting temperature, and has problems such as poor pick-up due to insufficient melt tension and occurrence of uneven thickness in sheet and film processing such as T-die extrusion and calendering. I have.

[0003]

SUMMARY OF THE INVENTION Sheets and films made of amorphous polyethylene terephthalate resin have improved melt tension, which is a problem in the processing of sheets and films.
An object of the present invention is to provide an amorphous polyethylene terephthalate resin having improved thickness uniformity.

[0004]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors to achieve the above object, an amorphous polyethylene terephthalate resin is mixed with an acrylic resin polymer having a specific composition and a specific molecular weight. As a result, the present inventors have found that the melt tension can be improved, and the necking property, take-off property, and uniformity of thickness, which are problems in sheet and film processing, can be satisfied.

That is, the present invention relates to (A) 100 parts by weight of an amorphous polyethylene terephthalate resin and (B) 50 to 20 parts by weight of an alkyl methacrylate having 50 to 80% by weight of methyl methacrylate and an alkyl group having 2 to 8 carbon atoms. % Of a mixture (b-1) of 0 to 20% by weight of a vinyl monomer copolymerizable therewith is first emulsion-polymerized, and methyl methacrylate is added in the presence of the resulting polymer latex. 20 to 80% by weight of at least one monomer selected from alkyl methacrylate and alkyl acrylate excluding
And 80 to 20% by weight of methyl methacrylate (b)
-2) A two-stage polymer obtained by polymerizing 40 to 5 parts by weight [100 parts by weight of (b-1) and (b-2) in total], and 0.4 g of the polymer is dissolved in 100 ml of toluene. A thermoplastic resin composition comprising 0.1 to 10 parts by weight of a polymer having a specific viscosity at 30 ° C. of 2 to 5 of the dissolved solution (Claim 1), and a two-stage polymer latex having an average particle size of 100
The alkyl methacrylate having an alkyl group having 2 to 8 carbon atoms in the thermoplastic resin composition (claim 2) and the mixture (b-1) according to claim 1 which is 0 ° or less is butyl methacrylate. (Claim 3).

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The amorphous polyethylene terephthalate resin modified according to the present invention has substantially no or low crystallinity.
A diol in which at least mol% is ethylene glycol;
A homopolymer, a copolymer or a mixture thereof obtained by polycondensation of a dicarboxylic acid in which 0 mol% or more is terephthalic acid or an alkyl ester thereof can be mentioned. As the copolymer, for example, 50 mol% or less of all carboxylic acids Or a copolymer of isophthalic acid or halogenated terephthalic acid, or a copolymer of poly (alkylene glycol), specifically diethylene glycol, in a range of 50 mol% or less of the total diol, or And alkylene glycols having 3 to 12 carbon atoms, for example, those obtained by copolymerizing 1,4-cyclohexanedimethanol. The two-stage polymer (B) which can be blended with the above amorphous polyethylene terephthalate-based resin to significantly improve the processability thereof is as follows. (B) Methyl methacrylate 50-80
A mixture (b-1) 60 comprising 50% by weight, 50 to 20% by weight of an alkyl methacrylate having an alkyl group having 2 to 8 carbon atoms, and 0 to 20% by weight of a vinyl monomer copolymerizable therewith.
To 95 parts by weight of emulsion polymerization, and in the presence of the resulting polymer latex, 20 to 80% by weight of at least one monomer selected from alkyl acrylate and alkyl methacrylate excluding methyl methacrylate and methyl methacrylate. 80 ~
A two-stage polymer obtained by polymerizing 40 to 5 parts by weight of a mixture (b-2) with 20% by weight.

In the mixture (b-1), the number of carbon atoms of the acrylic group of the alkyl methacrylate is preferably from 2 to 8 from the viewpoint of processability, and specific examples include ethyl methacrylate, butyl methacrylate, and 2-ethylhexyl methacrylate. No. One or more of these alkyl methacrylates can be used. The proportion of the alkyl methacrylate in the mixture (b-1) is 5 to 50% by weight, preferably 15% by weight.
It is preferable from the viewpoint of the uniformity of the resin composition to obtain from 50 to 50% by weight, more preferably from 20 to 40% by weight.

The copolymerizable monomers include aromatic vinyl compounds, unsaturated nitriles, alkyl acrylates,
Examples thereof include alkyl methacrylate having an alkyl group having 9 or more carbon atoms. They can be used alone or in combination of two or more. If the amount exceeds 20% by weight, it is not preferable from the viewpoint of processability.

When the specific viscosity at 30 ° C. of a solution obtained by dissolving 0.4 g of the polymer in 100 ml of toluene is less than 2, no sufficient effect of improving processability is obtained, and when it exceeds 5, a resin composition obtained is obtained. The product is not uniform and is not preferred. The average particle size of the emulsion polymerization latex of the two-stage polymer (B) by a suspension method is preferably 1,000 ° or less, more preferably 800 ° or less. If the average particle size exceeds 1000 °, it is difficult to obtain a sufficient dispersion, and undesired occurrence of bumps in the sheet and film is observed. If the average particle size is 50 ° or less, the stability of the latex is poor.

The two-stage polymer (B) can be produced, for example, by the following method. First, the mixture (b-1) is used to carry out emulsion polymerization in the presence of a suitable medium, an emulsifier and a polymerization initiator to obtain a polymer latex of the mixture (b-1).
Next, the mixture (b-2) is added to carry out polymerization. Water is usually used as a medium used in this emulsion polymerization,
As an emulsifier, a known anionic surfactant or nonionic surfactant is used, and as a polymerization initiator, an ordinary water-soluble or oil-soluble single or redox-based one is used. The polymerization conditions such as the polymerization temperature and time are not particularly limited, but may be appropriately adjusted so that the specific viscosity becomes 2 to 5, for example, as a surfactant in 200 parts of water as a surfactant, sodium dioctyl sulfosuccinate and an initiator. About 0.02 parts of potassium persulfate is added, and the conditions are maintained at about 65 ° C. and about 100 parts of the monomer are continuously added over 5 hours.

In order to make the average particle diameter of the latex by a final suspension method not more than 1000 ° or 800 ° or less, the amount of the emulsifier and the additional method may be appropriately adjusted. The initial amount of sodium succinate is about 0.5 part or more, and
Conditions such as addition of about 0.5 part at the time of / 2 amount additional polymerization can be adopted.

This two-stage polymer is obtained by forming a polymer layer of the mixture (b-2) so as to cover the surface of the polymer of the mixture (b-1).

The mixing ratio of the amorphous polyethylene terephthalate resin (A) and the two-stage polymer (B) is 0.1 to 10 parts by weight, preferably 0.1 to 10 parts by weight, per 100 parts by weight of (A). It is 3 to 10 parts by weight. When the addition amount of (B) is less than 0.1 part by weight, a sufficient effect of improving workability cannot be obtained,
If the amount exceeds 10 parts by weight, the resin viscosity at the time of processing becomes high, and processing becomes difficult.

As a method for producing the resin composition of the present invention, the components (A) and (B) are separately produced in advance, and then mixed using a conventional blending method such as a Henschel mixer or a tumbler. Thereafter, a method of shaping with a device used for normal shaping such as a single-screw extruder, a twin-screw extruder, or a Banbury mixer to form a resin composition can be employed. In order to improve the mechanical strength of the resin composition of the present invention, the graft copolymer is further added with 0.5 to 30.
Parts by weight may be added. The graft copolymer is polybutadiene or butadiene and an aromatic vinyl monomer,
Butadiene-based copolymers such as aromatic (meth) acrylate monomers, vinyl monomers copolymerizable therewith or crosslinkable monomers, aromatic vinyl monomers, alkyl (meth) acrylates and the like And those obtained by polymerizing a vinyl monomer mixture which can be copolymerized with the above.

The aromatic vinyl monomer used for the butadiene-based copolymer is a compound having one vinylic double bond and one or more benzene nuclei in the same molecule. Styrene, 4-ethoxystyrene, 4-propoxystyrene, 4-butoxystyrene,
2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,5-dimethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-
Chlorostyrene, 2,4-dichlorostyrene, 4-bromostyrene, 2,5-dichlorostyrene, α-methylstyrene and the like can be mentioned.

The aromatic (meth) acrylate monomer is an ester of (meth) acrylic acid and an aromatic compound having an alcoholic hydroxyl group, such as phenyl methacrylate.

As the copolymerizable vinyl monomer, (meth) acrylate is an ester compound of acrylic acid or methacrylic acid, specifically, methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, (Meth) acrylic acid esters of alcohols having 1 to 8 carbon atoms such as ethyl acrylate and butyl acrylate, acrylonitrile, methacrylonitrile, vinylidene cyanate, vinyl cyanide compounds such as 1,2-dicyanoethylene, maleimide compounds, (Meth) acrylic acid and the like.

Examples of the crosslinkable monomer include, but are not limited to, divinylbenzene monoethylene glycol dimethacrylate and polyethylene glycol dimethacrylate.

The graft copolymer is obtained by mixing the butadiene copolymer obtained as described above with an aromatic vinyl monomer, an alkyl (meth) acrylate and a vinyl monomer copolymerizable therewith. It is obtained by polymerizing a monomer mixture.

The (meth) acrylic acid ester is an ester compound of acrylic acid or methacrylic acid, and specifically includes methyl methacrylate, ethyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate and the like. (Meth) acrylic acid esters of alcohols having 1 to 8 carbon atoms are exemplified. The aromatic vinyl compound is a compound having one vinylic double bond and one or more benzene nuclei in the same molecule, and specifically, styrene, 4-methoxystyrene, 4-ethoxystyrene, and 4-propoxystyrene. , 4-butoxystyrene,
2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-ethylstyrene, 2,5-dimethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-
Chlorostyrene, 2,4-dichlorostyrene, 4-bromostyrene, 2,5-dichlorostyrene, α-methylstyrene and the like can be mentioned.

Other copolymerizable components include acrylonitrile, methacrylonitrile, vinylidene cyanate, vinyl cyanide compounds such as 1,2-dicyanoethylene, maleimide compounds, (meth) acrylic acid and the like.

In the resin composition of the present invention, fillers, fillers, foaming agents, antioxidants, heat stabilizers, light resistance improvers, ultraviolet absorbers, lubricants, plasticizers which are used as ordinary additives are used. , A release agent, an antistatic agent, a slidability improver, a colorant, and the like may be added.

[0023]

The present invention will be described in detail with reference to the following examples.

Example 1 Pure water 20 was added to a reactor equipped with a stirrer.
0 parts by weight, 1 part by weight of sodium dioctylsulfosuccinate and 0.03 parts by weight of potassium persulfate were charged, oxygen in the space and water was removed by flowing nitrogen, and then the content was heated to 65 ° C. while stirring. did. A monomer mixture (mixture (b-1)) composed of 52 parts by weight of methyl methacrylate and 28 parts by weight of butyl methacrylate was added thereto over 4 hours, and the mixture was heated and stirred for 1 hour to substantially complete the polymerization. Was. Thereafter, a monomer mixture (mixture (b-2)) consisting of 11 parts by weight of butyl acrylate and 9 parts by weight of methyl methacrylate was added over 1 hour, and the contents were kept at 65 ° C. for 1 hour and 30 minutes. After cooling, a two-stage polymer latex was obtained. An aqueous solution of calcium chloride was added to this latex to cause salting out and coagulation, followed by filtration, washing with water and drying to obtain a powdery two-stage polymer (B).

Example 2 A two-stage polymer was obtained in the same manner as in Example 1 except that 0.01 part of potassium persulfate was used.

Example 3 A two-stage polymer was obtained in the same manner as in Example 1 except that ethyl methacrylate was used instead of butyl methacrylate.

Example 4 A two-stage polymer was obtained in the same manner as in Example 1 except that 60 parts by weight of methyl methacrylate and 20 parts by weight of butyl methacrylate of the mixture (b-1) were used.

Example 5 A two-stage polymer was obtained in the same manner as in Example 1 except that the mixture (b-1) used 45 parts by weight of methyl methacrylate and 35 parts by weight of butyl methacrylate.

Example 6 Example 1 was repeated except that the mixture (b-1) was 50 parts by weight of methyl methacrylate, 28 parts by weight of butyl methacrylate, and 2 parts by weight of acrylonitrile.
A two-stage polymer was obtained in the same manner as described above.

Example 7 A two-stage polymer was obtained in the same manner as in Example 1 except that the mixture (b-2) was 5 parts by weight of methyl methacrylate and 15 parts by weight of ethyl acrylate.

Example 8 A two-stage polymer was prepared in the same manner as in Example 1 except that the mixture (b-2) was 9 parts by weight of methyl methacrylate, 9 parts by weight of butyl acrylate, and 2 parts by weight of acrylonitrile. Obtained.

EXAMPLE 9 The mixture (b-1) was 58 parts by weight of methyl methacrylate and 32 parts by weight of butyl methacrylate, and the mixture (b-2) was 4 parts by weight of methyl methacrylate and 4 parts by weight of butyl acrylate. Example 1 except for 6 parts by weight
A two-stage polymer was obtained in the same manner as described above.

Example 10 The mixture (b-1) was composed of 45 parts by weight of methyl methacrylate and 20 parts by weight of butyl methacrylate.
In parts by weight, the mixture (b-2) contained 1 part of methyl methacrylate.
A two-stage polymer was obtained in the same manner as in Example 1 except that 5 parts by weight and 20 parts by weight of butyl acrylate were used.

Example 11 A two-stage polymer was obtained in the same manner as in Example 1, except that sodium dioctylsulfosuccinate was 0.3 parts by weight.

Comparative Example 1 A two-stage polymer was obtained in the same manner as in Example 1 except that potassium persulfate was 0.1 part by weight.

Comparative Example 2 A two-stage polymer was obtained in the same manner as in Example 1 except that the amount of potassium persulfate was 0.008 parts by weight.

Comparative Example 3 A two-stage polymer was obtained in the same manner as in Example 1 except that only 80 parts by weight of methyl methacrylate was used as the mixture (b-1).

Comparative Example 4 A two-stage polymer was obtained in the same manner as in Comparative Example 3 except that 0.01 part of potassium persulfate was used.

(Comparative Example 5) In the mixture (b-1), 52 parts by weight of methyl methacrylate and 28 parts by weight of dodecyl methacrylate were used.
A two-stage polymer was obtained in the same manner as in Example 1 except that parts by weight were used.

Comparative Example 6 A two-stage polymer was obtained in the same manner as in Example 1 except that the mixture (b-1) used 52 parts by weight of methyl methacrylate and 28 parts by weight of butyl acrylate.

Comparative Example 7 A two-stage polymer was obtained in the same manner as in Example 1 except that 68 parts by weight of methyl methacrylate and 12 parts by weight of butyl methacrylate of the mixture (b-1) were used.

Comparative Example 8 A two-stage polymer was obtained in the same manner as in Example 1 except that the mixture (b-1) used 35 parts by weight of methyl methacrylate and 45 parts by weight of butyl methacrylate.

Comparative Example 9 The mixture (b-1) was 63 parts by weight of methyl methacrylate, 34 parts by weight of butyl methacrylate, and the mixture (b-2) was 1 part by weight of methyl methacrylate, Example 1 except for 2 parts by weight
A two-stage polymer was obtained in the same manner as described above.

Comparative Example 10 The mixture (b-1) was prepared by mixing 32 parts by weight of methyl methacrylate and 18 parts by weight of butyl methacrylate.
In parts by weight, the mixture (b-2) contains 2 parts of methyl methacrylate.
A two-stage polymer was obtained in the same manner as in Example 1 except that 5 parts by weight and 25 parts by weight of butyl acrylate were used.

The average particle size and specific viscosity η _sp (0.4 in the latex of the obtained two-stage polymer obtained by the turbidity method were determined.
g, 30 ° C.) are shown in Table 1.

Amorphous polyethylene terephthalate resin
(Estar6 manufactured by Eastman Chemical Company)
763) 100 parts by weight of (A) and 3 parts by weight of each of the obtained two-stage polymers (B) were blended to obtain extruded pellets. The melt tension was evaluated using the obtained pellets. Table 1 shows the results.

The method for measuring the melt tension is as follows. Using a pellet obtained by mixing the amorphous polyethylene terephthalate-based resin (A) and the two-stage copolymer (B), at a predetermined tensile speed (10 m / min) at 190 ° C. using a Capillograph manufactured by Toyo Seiki Co., Ltd. The melt tension was measured. In addition, M in the table
MA indicates methyl methacrylate, BMA indicates butyl methacrylate, EMA indicates ethyl methacrylate, dodecyl MA indicates dodecyl methacrylate, BA indicates butyl acrylate, EA indicates ethyl acrylate, and AN indicates acrylonitrile.

Comparative Example 11 Evaluation was made in the same manner as described above using only an amorphous polyethylene terephthalate resin without using a two-stage polymer.

[0049]

[Table 1]

[0050]

The resin composition comprising the amorphous polyethylene terephthalate resin (A) and the specific two-stage polymer (B) can improve necking, take-off property and thickness unevenness during sheet and film molding.

Continued on the front page F term (reference) 4J002 BN12X CF06W 4J011 PA40 PA69 PC02 PC06 4J026 AA45 BA27 BB03 DA04 EA06 FA02 GA06 4J100 AL03P AL03Q AL03R AL03S CA06 EA09 FA20

Claims (3)

[Claims] (A) 100 parts by weight of an amorphous polyethylene terephthalate resin and (B) methyl methacrylate 5
A mixture of 0 to 80% by weight, 50 to 20% by weight of an alkyl methacrylate having an alkyl group having 2 to 8 carbon atoms, and 0 to 20% by weight of a vinyl monomer copolymerizable therewith (b-
1) Emulsion polymerization of 60 to 95 parts by weight is carried out first, and 20 to 80% by weight of one or more monomers selected from alkyl methacrylate and alkyl acrylate excluding methyl methacrylate in the presence of the resulting polymer latex (B-2) of 40 to 5 parts by weight [a total of (b-1) and (b-2) 100 parts by weight]
Is a two-stage polymer obtained by polymerizing
A thermoplastic resin composition comprising 0.1 to 10 parts by weight of a polymer having a specific viscosity of 2 to 5 at 30 ° C. obtained by dissolving 4 g in 100 ml of toluene. 2. The two-stage polymer latex having an average particle size of 1
The thermoplastic resin composition according to claim 1, wherein the temperature is not more than 000 °. 3. The thermoplastic resin composition according to claim 1, wherein the alkyl methacrylate having an alkyl group having 2 to 8 carbon atoms in the mixture (b-1) is butyl methacrylate.