JPS6157643A - Polyethylene terephthalate resin composition - Google Patents

Abstract

PURPOSE:The titled composition providing a molded article promoting crystallization and having improved impact strength, rigidity, bleedout, and surface gloss, obtained by blending polyethylene terephthalate with a specific organic polymer, ionic copolymer, and polyalkylene glycol compound. CONSTITUTION:(A) 100pts.wt. polyethylene terephthalate is blended with (B) 1- 20pts.wt. organic polymer containing a group shown by the formula I (R<1> is 2- 5C alkylene; R<2> is hydrocarbon group consisting of aliphatic, alicyclic, aromatic or their combination, or hydrocarbon terminal group containing nitrogen, sulfur, phosphorus, oxygen or halogen in part of it; n is 1-50) and -COOM (M is alkali metal), (C) 1-20pts.wt. ionic copolymer consisting of an alpha-olefin and an alpha,beta- unsaturated carboxylic acid, wherein part of the carboxylic acid is an alkali metal salt, and (D) 0.5-10pts.wt. polyalkylene glycol compound shown by the formula II (R<3> and R<4> are H, or lower alkyl; R<5> is 2-5C alkylene; n is 1-50).

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a crystalline polyethylene terephthalate resin composition with a fast crystallization rate useful in injection molding applications.

Polyethylene terephthalate is widely used in the fields of fibers, films, bottles, etc. due to its excellent properties, but in the field of injection molding, it is inherently an extremely superior molding material that has a recyclable property. regardless of,
Not used that much. This is because polyethylene terephthalate has a slow crystallization rate at low temperatures, so it is often necessary to maintain the mold temperature at 160°C or higher during injection molding, and such high mold temperatures result in significantly longer molding cycles, which is preferable for production. Due to unforeseen circumstances. In order to shorten the molding cycle, if the mold temperature t'' is set close to 100℃, crystallization will hardly progress and the mechanical properties and dimensional stability of the molded product will be improved.
The surface appearance is extremely poor.

(Prior Art) In order to improve these drawbacks, conventional methods have been proposed.

The present inventors previously discovered that the general formula +R"O+nR2 and -COO
We proposed a method to greatly improve the above-mentioned drawbacks by blending an organic polymer containing a group represented by M into polyethylene terephthalate (Patent Application No. 11F159-895).
No. 49). However, this method has the disadvantage that if the addition of the organic polymer is increased in order to lower the mold temperature, the impact strength of the polyethylene terephthalate resin composition decreases.

(Problems to be Solved by the Invention) Therefore, the present inventors conducted further research to improve the @impact strength of the polyethylene terephthalate resin composition, and as a result, the resin composition of the present invention that solved this problem was found. Reached.

(Means for Solving the Problems) That is, the present invention provides the following: Prisoner component; 100 parts by weight of polyethylene terephthalate (B) component; (B-1) General formula +EC"0-)-R2"t' and (B-2) a group represented by the general formula -COOM 1 to 20 parts by weight (wherein R1 is an alkylene group having 2 to 5 carbon atoms, R2 is an aliphatic or aliphatic group having 1 or more carbon atoms) A hydrocarbon group consisting of cyclic, aromatic or a combination thereof, or a part thereof is nitrogen, sulfur,
Hydrocarbon end group containing phosphorus, oxygen, halogen, n is 1
~1 integer, M is an alkali metal) (C) component: an ionic compound consisting of an α-olefin and an α,β-unsaturated carboxylic acid, at least a part of the carboxylic acid being an alkali metal salt. Polymer 1~
20! Amount ■) Ingredients: 0.5 to 10 parts by weight of a polyalkylene glycol compound represented by the general formula R30 + R5 (g) ±4 (where R3t R' is H or a lower alkyl group, and R5 is a compound having 2 to 5 carbon atoms) This is a polyethylene terephthalate resin composition formed by mixing alkylene groups (n is an integer of 1 to 50).

Next, the present invention will be explained in detail. The polyethylene terephthalate used as component (2) of the present invention is a polyester mainly composed of repeating units of ethylene terephthalate.

Generally, it is produced using ethylene glycol and terephthalic acid, and other acid components and glycol components may be copolymerized within a range that does not impair crystallinity. Acid components include dicarboxylic acids such as isophthalic acid, naphthalene dicarboxylic acid, adipine, sebacic acid, and cyclohexanedicarboxylic acid; glycol components include trimethylene glycol, tetramethylene glycol, hexamethylene glycol,
polyethylene glycol, polypropylene glycol,
Examples include polytetramethylene glycol, a copolymer of polyethylene glycol and polypropylene glycol, and the like.

Generally at least 80% of the acid and glycol components
Polyethylene terephthalate containing ethylene glycol or terephthalic acid, preferably at least 90 moles, is used, preferably at least 80 moles, and more preferably at least 90 moles.

The polyethylene terephthalate component (5) has an intrinsic viscosity of 0.3 or more, preferably 0.0 when measured at 1:1 weight ratio polymerization solvent of phenol and tetrachloroethane at °C.
．． 5 or more, and is produced by melt polycondensation reaction or a combination of this and solid phase polymerization reaction.

Component (B) has the general formula +R"0 +-R2,-COOM
It is an organic copolymer that also has the groups shown below. Here, R1 is an alkylene group having 2 to 5 carbon atoms, specifically an ethylene group, a trimethylene group, a tetramethylene group, or a pentamethylene group. R2 is an aliphatic, alicyclic, aromatic, or a combination thereof hydrocarbon group having one or more carbon atoms, or a part thereof is nitrogen, sulfur, phosphorus, oxygen,
It is a hydrocarbon terminal group containing 10 groups, specifically a methyl group, an ethyl group, a propyl group, a glycylyl group, a phenyl group, etc. Moreover, M is an alkali metal, specifically sodium, potassium, etc.

n is an integer of 1 to 5o, preferably 2 to 30.

Component (B) consists of an unsaturated monomer having a group represented by general formula (B-1) and an unsaturated monomer having a group represented by general formula (B-2) or a group derivable therefrom. In some cases, these unsaturated monomers can be obtained by copolymerizing other unsaturated monomers having copolymerizability.

Examples of those having groups include (poly)alkylene glycol monoalkyl ethers (meth) such as polyethylene glycol monomethyl ether methacrylate, polypropylene glycol monomethyl ether methacrylate, and polyethylene glycol monoethyl ether acrylate.
These are acrylates, phenoxypolyalkylene glycol (meth)acrylates, and alkoxypolyalkylene glycol vinyl ethers.

Examples of those having a -COOM group include sodium methacrylate, potassium methacrylate, and sodium acrylate. Compounds copolymerizable with these monomers include, for example, α-olefins having 50 or less carbon atoms, vinyl ethers, vinyl esters, acrylic acid, methacrylic acid, acrylic esters, methacrylic esters, etc. , styrene, etc. The term "organic copolymer" used here refers to a wide range of copolymers, including all copolymers other than monomers.
Including those existing as polymers, generally dimers or more, preferably trimers or more, particularly preferably 10 to 2
00 mer is used.

The molar ratio of the unsaturated monomer with the general formula (B-1) 't- and the unsaturated monomer with the general formula CB-2) is (
R71)/(B-2)=0.1-9, preferably 0.
It is 2-3, particularly preferably 0.3-1.

Further, the unsaturated monomer copolymerized with these unsaturated monomers can be added in an amount of 0 to 50 moles, preferably 1 to 20%, expressed in moles based on the total monomers.

The organic copolymer of component (1) is polymerized by an appropriately selected method such as non-catalytic thermal polymerization, radical polymerization, cationic polymerization, anionic polymerization, coordination polymerization, etc., depending on the polymerization performance.

In addition, the component (B) is added to the 1i association with the above (B-1) and/or
Alternatively, it can be obtained by introducing a group represented by (B-2), such as a polymer having a carboxyl group or an acid anhydride group in the main chain or side chain, such as ethylene/acrylic acid copolymer, ethylene/acrylic acid copolymer, By partially graft polymerizing alkylene glycol monoalkyl ether to methacrylic acid copolymer, maleic anhydride-modified polystyrene, maleic anhydride-modified ethylene/vinyl acetate copolymer, etc., and neutralizing with the remaining carboxyl base alkali. You can also get

The polymer of component (B) is represented by the general formula (B-1) (
Poly)alkylene glycol monoether visiting conductor chain t
-2 or more, preferably 3 or more, particularly preferably 5 to 80
containing 1 or more carboxylic acid groups represented by general formula (B-2), preferably 5 or more, particularly preferably 10 to 10
The one containing 0 is used.

In general, the number of carbon atoms in the polymer skeleton is 10, the general formula (B-1
) is 0.5 to 465, preferably 1 to 3,
A compound containing 0.5 to 4.5, preferably 2 to 4, groups represented by formula (B-2) is suitable.

(The blending amount of the Bl component is polyethylene terephthalate 1
If the amount is less than 1 part by weight, moldability in a low-temperature mold will be poor.

Moreover, if it exceeds 20 parts by weight, mechanical properties and heat resistance will deteriorate, which is not preferable.

Component (C) of the composition of the present invention is an α-olefin α, β-
It is an ionic copolymer obtained by reacting a copolymer of unsaturated carboxylic acid with an alkali metal compound.

It can be produced by the method described in Japanese Patent Publication No. 39-6810. Here, ethylene, propylene, and butene-1 are used as the α-olefin, and among them, ethylene is preferred because it has high polymerizability and provides a polymer with a high molecular weight. Further, as the α,β-unsaturated carboxylic acid, acrylic acid, methacrylic acid, itaconic acid, and maleic acid are used. The α-olefin component in the copolymer preferably has a group mole S or more, particularly 80 mole or more, and preferably has at least 10 mole of carboxylic acid neutralized with sodium or potassium.

The blending amount of component (C) is polyethylene terephthalate 10
If the amount is less than 1 part by weight, the present invention will not be effective, and if it exceeds 1 part by weight, the rigidity of the composition will decrease, which is not preferable.

Particularly preferred such ionic copolymers include a series of polymers commercially available from EI DuPont under the trade name "Surlyn".

The component (■) of the composition of the present invention has the general formula R30+Ro-5d
It is a polyalkylene glycol compound represented by

Here, R3 and R4 represent H or a lower alkyl group having 1 to 5 carbon atoms, and R5 represents an alkylene group having 2 to 5 carbon atoms. Moreover, n is an integer of 1-50.

Specific examples include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and their mono- or dialkyl ethers (for example, monomethyl or dimethyl ale, monoethyl or diethyl ether, monopropyl or dipropyl ether, monobutyl or dibutyl ether, etc.). I can do things. In the composition of the present invention, it is preferable that the polyalkylene glycol compound has both ends alkyl etherified in view of less hydrolytic deterioration of polyethylene terephthalate during molding. It is preferable that n is 5 or more. If it is less than 5, component (2) tends to bleed out on the surface of the molded product. [F] Acid component content is 100% polyethylene terephthalate! is 0.5 to 10 parts by weight. 0.
If it is less than 5, the effect of the present invention is not achieved, and if it exceeds 10 t, component (2) tends to bleed out onto the surface of the molded product, which is not preferable.

(Effect) The composition of the present invention crystallizes quickly even at a relatively low temperature, and has a crystallization rate of 100%.
Uniform crystallization occurs even at mold temperatures below ℃. The resulting molded product has excellent surface gloss, does not bleed out of the additive at high temperatures, and has good mechanical strength such as impact strength, making it an excellent material for injection molding.

The reason why the composition of the present invention has the above-mentioned excellent properties is not clear, but the reason is that component (B) has good compatibility with component (■), suppresses high-temperature bleed-out of component This is thought to be due to a synergistic effect, such as helping the compatibility of polyethylene terephthalate with polyethylene terephthalate and, as a result, suppressing the drop in impact strength.

The composition of the present invention can be expected to be even more effective when used in combination with conventionally used nucleating agents and crystallization promoters. Examples of these nucleating agents and crystallization promoters include inorganic compounds such as talc, clay, mica, and silica, sodium and potassium salts of organic carboxylic acids such as stearic acid and montanic acid, and polynuclear cyclic compounds such as phenanthrene. .

Reinforcing agents such as glass fibers, carbon fibers, wollastonite, whiskers, etc. can be added to the compositions of the present invention. In particular, it is preferable to add 5 to 60% by weight of glass fiber to the entire composition, as it significantly improves mechanical properties. Furthermore, flame retardants, ultraviolet absorbers, antioxidants, colorants, and hydrolysis-resistant agents may be added. Furthermore, other thermoplastic resins such as polybutylene terephthalate, polyethylene, polypropylene, polycarbonate, polyamide, polystyrene, etc. may be blended.

The polyethylene terephthalate resin composition of the present invention is produced by a conventional method. For example, the prisoner (I31).

(C), Q) Ingredients, if necessary, the above-mentioned nucleating agent, crystallization promoter, reinforcing agent, flame retardant, coloring agent, antioxidant, etc. are tri-blended in a suitable mixer, and then transferred to an extruder, One day,
It is manufactured by melt-kneading in a Banbury mixer or the like.

(Examples) Next, examples and comparative examples of the present invention will be described, but the present invention is not limited in any way by the following examples.

Polyethylene glycol monomethyl ether methacrylate (molecular weight 496) 250 f, methacrylic acid 2
A glass reactor was charged with 50 tons of azobisisobutyronitrile, 10 tons of azobisisobutyronitrile, and 5 tons of ethanol, and after polymerization at 80°C for 3 hours with stirring in a nitrogen stream, 79 f of caustic soda was added.
After partial neutralization, the organic polymer CB) of the present invention was obtained.

Examples 1 to 7, Comparative Examples 1 to 2 Polyethylene terephthalate (manufactured by Kuraray Co., Ltd., in a 1:1 weight mixed solvent of phenol/tetrachloroethane, intrinsic viscosity 0.68 at 30°C) and compounded components according to the present invention (
Bl, (C), ■) and glass fiber (C8O3JA429 manufactured by Asahi Fiberglass Co., Ltd.) were triblended at the blending ratios shown in Table 1. After, 40wφ, 1
The mixture was melt-kneaded at 280° C. in a single screw extruder of 28 mm. The obtained pellets were dried with hot air at t-130°C for 10 hours, and then processed using an injection molding machine N-100II manufactured by Nippon Steel Corporation.
B type, resin temperature 280℃, injection pressure 400~60
Molding was carried out at a temperature of 0 Kf/no, a mold temperature of 90°C, a cooling time of 20 seconds, and a molding cycle of 40 seconds.

The crystallization promotion effect was measured using a PerkinElmer differential calorimeter model DSCII from 60°C to 290°C for 100°C for each pellet) 1-melt diameter sample prepared by quenching with ice water.
The exothermic peak temperature (Tc
c) and the exothermic peak temperature (Tc) when the temperature was lowered at the same rate from 290°C.

'The lower the Tea, the lower the mold temperature, and the higher the Tc, the shorter the molding cycle. The measurements of Izotsu impact strength and bending rigidity are conducted according to ASTM D-256, respectively.
'Compliant with D-790.

The presence or absence of bleed-out was determined by visually observing the presence or absence of bleed-out material on the sheet surface after the molded sheet was left in a gear oven at 180° C. for 1 day. Moreover, the surface appearance was judged by whether the molded sheet was visually uniform and glossy.

(Effects of the Invention) As shown in Table 1, although crystallization is certainly promoted when only the organic polymer of component (B) is blended, the impact strength is significantly reduced (Comparative Examples 13 and 14). However, (C)
.

When 0 component is blended in an appropriate range, crystallization is promoted and a composition with good impact strength, rigidity, bleed-out, and surface gloss can be obtained.

*(A) PET: Polyethylene terephthalate TB)
Organic polymer: Polyethylene glycol monomethyl ether terpolymer of methacrylate, methacrylic acid, and sodium methacrylate DM: Polyethylene glycol dimethyl ether (weight average molecular weight: 1000)

Claims (1)

[Scope of Claims] Component (A); 100 parts by weight of polyethylene terephthalate (B) Component; (B-1) a group represented by the general formula -(R^1O)-_nR^2 and (B-2) the general formula -1 to 20 parts by weight of an organic polymer containing a group represented by COOM (where R^1 is an alkylene group having 2 to 5 carbon atoms, R^
2 is a hydrocarbon group consisting of aliphatic, alicyclic, aromatic or a combination thereof having 1 or more carbon atoms, or a hydrocarbon terminal group containing nitrogen, sulfur, phosphorus, oxygen, or halogen as a part thereof; n is (an integer from 1 to 50, M is an alkali metal) Component; an ionic copolymer consisting of an α-olefin and an α, β-unsaturated carboxylic acid, at least a part of which is an alkali metal salt. Combined 1 to 20 parts by weight component (D); 0.5 to 10 parts by weight of a polyalkylene glycol compound represented by the general formula R^3O-(R^5O)-R^4 (however, R^3, R^4 represents H or a lower alkyl group, R
5^ is an alkylene group having 2 to 5 carbon atoms, and n is an integer of 1 to 50).